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General Science => General Science => Topic started by: Chemistry4me on 12/04/2009 03:55:29

Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 12/04/2009 03:55:29
Would we be able to see further if we had bigger eye-balls?  [:o]
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 12/04/2009 11:19:41
Would we be able to see further if we had bigger eye-balls?  [:o]
Do you want to replace your eye-balls with watermelons?  [;D]
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 12/04/2009 11:49:15
Well, if it'll help me see better then YES!
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 12/04/2009 12:09:23
Perhaps I have not explained myself properly? I was thinking if we had a bigger lens would we be able to see further (i.e, have higher visual acuity)?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Variola on 12/04/2009 13:09:33
Perhaps I have not explained myself properly? I was thinking if we had a bigger lens would we be able to see further (i.e, have higher visual acuity)?

I think its more to do with the structure than the actual size, falcons and other birds of prey can spot small rodents hidden in the grass from way up high, yet their eyes are quite small.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 12/04/2009 13:11:24
Thank you for your comment. [:)]
At least we're getting somewhere. [::)]
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Yomi on 12/04/2009 13:17:28
We can say that size doesent really matter in sense organs I think Hawk or an Eagle can point out their prey from high distance wven the diametre of eyeballs is just about 1-2 cms!!!!! Quiet amazing creatures....... [::)] [::)] [::)] [::)] [::)]
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 12/04/2009 13:18:29
So what are they doing different to us that makes them see better?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Variola on 12/04/2009 13:18:46
We can say that size doesent really matter in sense organs I think Hawk or an Eagle can point out their prey from high distance wven the diametre of eyeballs is just about 1-2 cms!!!!! Quiet amazing creatures....... [::)] [::)] [::)] [::)] [::)]




There is an echo in here... lol
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 12/04/2009 13:19:45
And I said we were getting somewhere? No? [:D]
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Variola on 12/04/2009 13:28:55
http://videos.howstuffworks.com/hsw/21716-birds-of-prey-the-eagles-eye-test-video.htm (http://videos.howstuffworks.com/hsw/21716-birds-of-prey-the-eagles-eye-test-video.htm)

Run it along towards the end of the video,till about 3.30, more of an explanation on how the eagle's eye works.

Apparently their eyes are big for their body ratio, if ours were the same size they would be as big as oranges. They also have a large iris,which allows a bigger picture to be projected onto the retina.On the retina there are light sensitive receptors called cones, which code for colour and detail. Eagles have 600,00 cones per sq mm, 4 times as many as humans.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 12/04/2009 13:30:35
Okay, forgetting about the cones for a second. If we had eyes the size of oranges our vision would be improved right? [:)]
Title: Would we be able to see further if we had bigger eye-balls?
Post by: graham.d on 12/04/2009 13:54:14
Well the size of the aperture would enable better seeing in low light levels, though the lens has to be more complex to prevent aberrations and worse acuity. But generally, if the eyes were bigger it would enable a greater density of receptors and greater light gathering capability. I guess we have evolved eyes that are adequate for our use. It would be hard to see how a complex lens could have "evolved".
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 12/04/2009 17:32:56
Okay, forgetting about the cones for a second. If we had eyes the size of oranges our vision would be improved right? [:)]
At least this is what astronomers must have thought, otherwise we can't explain why they have constructed even greater telescopes... [8D]
Title: Would we be able to see further if we had bigger eye-balls?
Post by: graham.d on 12/04/2009 18:46:18
In astronomy it is important to have a very large aperture because the light levels are extremely low. You can also avoid aberrations by using a parabolic reflector. This concept has never evolved naturally - I blame biologists :-)
Title: Would we be able to see further if we had bigger eye-balls?
Post by: LeeE on 12/04/2009 19:39:21
Basically, what graham.d has said.

The question is actually rather mis-phrased.  What I think it should have said is "would bigger eyeballs increase the resolution of our eyes?  After all, we can all see the same 'distance'.

There are two factors at play here; the lens and the image-detector.

Assuming the same field of view, if the larger eyeball has a larger image area but the same density of photo-receptors as a normal eyeball then there will be more total receptors across the image area in the larger eyeball, increasing its resolution.

However, a larger lens just allows more light through, making the image brighter.  Even with our normal eyeballs though, unless it's pretty dark, the iris is normally contracted to reduce the amount of light entering the eye because it would otherwise be too bright.  With the same photo-receptors in a larger eye then, the iris would still have to contract to the point where the light levels reaching the receptors is the same as for a normal eye, so in bright light the size of the larger lens in the bigger eyeball has to be reduced anyway.

Another relevant factor are the imperfections in the lens.  If the number of imperfections in the lens is the same per unit area then the larger lens will have more imperfections in it, which will reduce it's resolution compared with a smaller lens.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 12/04/2009 21:27:12
In astronomy it is important to have a very large aperture because the light levels are extremely low. You can also avoid aberrations by using a parabolic reflector. This concept has never evolved naturally - I blame biologists :-)
Ok, let's say you want to make observations in a clear, bright day. Assuming the same kinds of lens qualities, would you choose a little or a bigger telescope/binocular for a greater resolution?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: graham.d on 12/04/2009 21:51:51
If you are talking about a simple, single lens, then it would be fairly small. Not so small as to get distortions because of diffraction, but big enough to capture an appropriate amount of light for the sensitivity of the sensors. 35mm camera design over the years is a good example. A simple single lens of focal length of (say) 50mm gives just about acceptable performance with an aperture of f4.5. Better lenses developed in the early 20th century (like the Tessar lens) comprised 4 elements and worked well at f2.8. Modern many element lenses are good at f1.4 or wider. All these lenses are optimum for resolution at a stop or two smaller aperture and all the lenses will start to have diffraction problems at f22 of smaller. 
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 13/04/2009 03:59:44
That's fascinating stuff. [:)]
You want me to change the title of the thread LeeE (even though I know you have a thing against it (http://www.thenakedscientists.com/forum/index.php?topic=21062.0))?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: stereologist on 13/04/2009 04:31:57
Take a look at the eye of the horseshoe crab. This creature has mastered 3 methods that allow the eye to perceive images over an amazingly wide range of light intensities.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 13/04/2009 12:41:04
Okay, so if you were to sum up the answer to the question in three sentences, what will it be?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: graham.d on 13/04/2009 13:35:58
Can I write very long sentences? :-)

It is really hard to do this because your question needs many caveats to answer it properly.

1. Simply making the eye bigger does not help because it needs more doing to it, such as adding more receptors and/or a more complex lens.

2. If we assume that the size of an individual receptor (like a pixel) is fixed and that the basic eye design should not change, then making the eye bigger will create a larger area of receptors for the same field of view and, providing the brain is changed to cope with the information, will give a higher resolution, thus enabling a proportionate improvement in the distance vision with the same light levels.

3. The same effect could be achieved by keeping the eye the same size and design but having more, and smaller, receptors; this is why a 20 Mega-pixel camera has better resolution than a 4 Mega-pixel camera.


The eye and brain are very complex in how they work together. An eagle, for example, has much better resolution than a human eye, not because of the size of the eye compared to a human eye, but because of the size, structure and speciality of the receptors (about 5x the density of the human eye). They have quite poor night vision though. Owls, in contrast, have very good night vision and have very large eyes compared to their head size. The eyes are fixed in their heads hence the remarkable, but necessary, head movements owls can achieve. Their brain sorts out the parallax problems that arise. All designs, whether created by humans or formed by evolution, are compromises that achieve what they need to for optimum use. Simply changing one of many features will alter the performance in one area at the expense of another.

Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 13/04/2009 13:42:29
Wow, thank you kind Sir. [:)]
You've made it fairly clear for me to see. [;D]
I don't think anyone can beat that.

Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 13/04/2009 14:04:06
I guess we have evolved eyes that are adequate for our use.

I think this is the best answer to the question 'Why aren't our eyes as good as an Eagle's?' A bird of prey needs to fly high to enable it to see a very wide field, but it's eye must be capable of spotting prey from such a distance. Being able to see so well at great distances would be of no benefit if you could not then launch an attack at high speed. Since birds of prey do have the ability for high speed attack, the high resolution vision is supported. The two capabilities are necessary to be of use to each other. One without the other would be pointless.

Since humans have never had the capability of high speed attack on our prey, or the necessity, such high resolution vision would be pointless and could infact be counterproductive. Too much detail could lead to confusion.

As to this thread's question, I should think a larger eye would not be necessary for improved long distance vision. Perhaps an improved lens and retina might be all that would be required, along with an improved 'processor'.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 13/04/2009 14:59:35
As to this thread's question, I should think a larger eye would not be necessary for improved long distance vision.
Certainly, I agree with it. But it depends on how much "long distance". If you want to increase that distance a lot, before or less you'll have to increas the eye's dimensions.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: LeeE on 15/04/2009 00:31:53
That's fascinating stuff. [:)]
You want me to change the title of the thread LeeE (even though I know you have a thing against it (http://www.thenakedscientists.com/forum/index.php?topic=21062.0))?

Nope.  Many people would phrase the question that way and by reading the subsequent posts they might learn something about the question as well as the answer.

Plus, of course, subsequent posts referring to a mis-phrased question would then seem nonsensical.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 15/04/2009 12:19:17
As to this thread's question, I should think a larger eye would not be necessary for improved long distance vision.
Certainly, I agree with it. But it depends on how much "long distance". If you want to increase that distance a lot, before or less you'll have to increas the eye's dimensions.

I'm not so sure that this would be the case. I can look at the Moon, without the need for a telescope, and quite clearly make out the surface detail (to an extent). I think if I wanted to be able to make out more detail of a far distant object, it is more the sensor (retina) which requires extra capability than the receiver.

Let me explain my reasoning here.

Take a Nikon D40 - 6 megapixel DSLR body and fit a Nikon 85mm f2.8 lens. With the lens set to infinity, take a shot of an object on the horizon. Now, using your computer as the processor, enlarge that object to the maximum at which it remains discernable.

Now compare that with the identical shot, taken under identical conditions with the same Nikon 85 mm f2.8 lens, but using a Nikon D3x 24.5 megapixel DSLR body.

The extent to which this shot can be enlarged with the object remaining discernable will be much greater (approx. 4 X greater), yet it is the result from the very same lens and the same processor, only the sensor has been improved.

Our eye works in much the same way as this camera with a fixed focal length lens. We make sense of a particular object within our field of vision by focusing the lens on that object and then getting the brain to concentrate on it. With an improved sensor, we would be able to distinguish more detail of that object.

The eagle has an eyeball roughly the same size as a human, yet it can see far better than a human. The reason for this is that the human retina has 6.4m cones, 200k of which are in the fovea, the eagle has approximately 32m cones, 5 times that of a human. The back of the eagle’s eyeball is flatter and the retina bigger, but the lens is not much different. The brain works in a similar way to a digital zoom on a camera. It concentrates on one area of the whole picture. If that picture has a higher resolution, it can make more sense of the detail. In effect, we ‘digitally’ zoom in on an object.

If we (and eagles) were to be able to zoom in on an object optically, in the same way as a camera zoom lens, our eye would need to be restructured since eyes have a single element lens. To enable optical zooming, like a camera lens, eyes would need a multiple moving element lenses. This would create a problem, however, in that there would be a considerable loss of field of vision.

In conclusion, our eyeball does not need to be bigger in order to see further. We can see just as far as an eagle. What it needs is an improved retina in order to be able to discern more from a small area of that sensor.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 15/04/2009 13:21:08
So the Hubble telescope is just an eye with trillions and trillions of cones. Is that what you're saying?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: graham.d on 15/04/2009 13:59:31
There are two factors (at least in the main, for this discussion) - resolution and sensitivity. To get more resolution you need more sensors looking at a particular field of view. There is a limit to how sensitive a receptor or photosensor can get. To get more sensitivity you need to increase the total light gathered by having as wide an aperture as possible. Astronomical telescope design has always been about trying to achieve this whilst keeping aberrations to a minimum because the amount of light arriving from distant stars is very, very small indeed. The other way to improve the light gathered is to stay "on-target" for a long time to integrate the total light gathered - a long exposure. Hubble does both of these things by having a large parabolic (at least it was supposed to be) reflector and very steady positioning with no nasty effects from the light passing through the atmosphere. 

In fact I just looked up Hubble and its CCD array (image sensor) is actually only 2.5 Mpixel, which is very poor by today's standards.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 15/04/2009 14:03:53
So larger eye-balls = more sensitivity? Assuming that everything else remains the same.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: graham.d on 15/04/2009 14:08:18
Yes. The eagle, as I said (and also Don) gets more resolution because it packs more pixels into the same area.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 15/04/2009 14:50:25
There are two factors (at least in the main, for this discussion) - resolution and sensitivity. To get more resolution you need more sensors looking at a particular field of view. There is a limit to how sensitive a receptor or photosensor can get. To get more sensitivity you need to increase the total light gathered by having as wide an aperture as possible. Astronomical telescope design has always been about trying to achieve this whilst keeping aberrations to a minimum because the amount of light arriving from distant stars is very, very small indeed. The other way to improve the light gathered is to stay "on-target" for a long time to integrate the total light gathered - a long exposure. Hubble does both of these things by having a large parabolic (at least it was supposed to be) reflector and very steady positioning with no nasty effects from the light passing through the atmosphere. 

In fact I just looked up Hubble and its CCD array (image sensor) is actually only 2.5 Mpixel, which is very poor by today's standards.
The field of view is also relevant.
The 2.5Mpx is enough for the field of view which is required and it probably reflects the fact that the resolution is largely diffraction limited in any case; more pixels would just produce the same amount of 'blurriness' in the final picture.
Getting a meaningful discussion about this sort of topic requires a totally holistic view - particularly where the Intelligent Designer is concerned. (Sorry- just kidding.)
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 15/04/2009 15:30:13
You had me worried there sophiecentaur.

Look at this picture

 [ Invalid Attachment ]

This was taken on my Nikon D300 12.3 mp and printed (slightly cropped)to 36" x 22"

If this had been taken on a 6mp camera, it would not be possible to print to this size without the diagonal lines being out of kilter. To get a print any bigger than this, I would need a camera with more pixels to its sensor.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 15/04/2009 15:44:14
As to this thread's question, I should think a larger eye would not be necessary for improved long distance vision.
Certainly, I agree with it. But it depends on how much "long distance". If you want to increase that distance a lot, before or less you'll have to increas the eye's dimensions.

I'm not so sure that this would be the case. I can look at the Moon, without the need for a telescope, and quite clearly make out the surface detail (to an extent). I think if I wanted to be able to make out more detail of a far distant object, it is more the sensor (retina) which requires extra capability than the receiver.

Let me explain my reasoning here.

Take a Nikon D40 - 6 megapixel DSLR body and fit a Nikon 85mm f2.8 lens. With the lens set to infinity, take a shot of an object on the horizon. Now, using your computer as the processor, enlarge that object to the maximum at which it remains discernable.

Now compare that with the identical shot, taken under identical conditions with the same Nikon 85 mm f2.8 lens, but using a Nikon D3x 24.5 megapixel DSLR body.

The extent to which this shot can be enlarged with the object remaining discernable will be much greater (approx. 4 X greater), yet it is the result from the very same lens and the same processor, only the sensor has been improved.

Our eye works in much the same way as this camera with a fixed focal length lens. We make sense of a particular object within our field of vision by focusing the lens on that object and then getting the brain to concentrate on it. With an improved sensor, we would be able to distinguish more detail of that object.

The eagle has an eyeball roughly the same size as a human, yet it can see far better than a human. The reason for this is that the human retina has 6.4m cones, 200k of which are in the fovea, the eagle has approximately 32m cones, 5 times that of a human. The back of the eagle’s eyeball is flatter and the retina bigger, but the lens is not much different. The brain works in a similar way to a digital zoom on a camera. It concentrates on one area of the whole picture. If that picture has a higher resolution, it can make more sense of the detail. In effect, we ‘digitally’ zoom in on an object.

If we (and eagles) were to be able to zoom in on an object optically, in the same way as a camera zoom lens, our eye would need to be restructured since eyes have a single element lens. To enable optical zooming, like a camera lens, eyes would need a multiple moving element lenses. This would create a problem, however, in that there would be a considerable loss of field of vision.

In conclusion, our eyeball does not need to be bigger in order to see further. We can see just as far as an eagle. What it needs is an improved retina in order to be able to discern more from a small area of that sensor.

Ok, can you show me in which way exactly you can device a camera 85 mm to discern two 1mm spots which are 1 mm far each other, on the Moon's surface?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: dentstudent on 15/04/2009 15:55:55
Not sure that this has already been mentioned, but what about exposure? Isn't this a fundamental difference between a camera/telescope and an eye, which makes comparisons rather difficult? A telescope with a camera effectively catch photons over a pre-determined time period. This is how the Hubble is able to take such breath-taking shots of space, since it can sit and "look" at the same point in space and collect the infrequent photons that arrive. The eye can't do this.

In answer to Lightarrow's question, wouldn't it be possible to discern these two 1mm spots with a camera if you could get enough magnification, if you could keep the camera and lenses still enough, and if you could have an appropriate exposure time?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 15/04/2009 16:45:44
lightarrow To discern 2 x 1mm points 1mm apart on the Moon's surface is rather going to the extreme. The sensor required for this, I think, would need 386,242.5 megapixels. This would mean fitting more than 10k times more cones on an eagle's retina, or 50k more times for a human. This would hardly be termed as 'being able to see a long way', this is rather into the realms of Superman! But I concede, that for such incredible vision, the eye would need to be very much bigger.

Can you make do with a telescope?

dentstudent The amount of light entering the eye (or camera) is a factor in what we can see. As you say, Hubble can keep still and gather a huge amount of light over a period of time, which we cannot. Some large format cameras of 100+ mp do require exposure times running into minutes.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 15/04/2009 18:38:19
lightarrow To discern 2 x 1mm points 1mm apart on the Moon's surface is rather going to the extreme. The sensor required for this, I think, would need 386,242.5 megapixels. This would mean fitting more than 10k times more cones on an eagle's retina, or 50k more times for a human. This would hardly be termed as 'being able to see a long way', this is rather into the realms of Superman!
No.
Not even Superman could do it, not even a sensor with infinite pixels/cm2, because of diffraction: the resolving power d of an optical system is d = λ/2NA where NA = numerical aperture and λ = wavelength; or you can consider the angular resolution: sinθ = 1.22λ/D where D = diametre of lens' aperture. Make the computations and you'll find that you can NEVER resolve those two points in the visible range with an 85 mm lens.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 15/04/2009 18:41:32
In answer to Lightarrow's question, wouldn't it be possible to discern these two 1mm spots with a camera if you could get enough magnification, if you could keep the camera and lenses still enough, and if you could have an appropriate exposure time?
See my answer to Don_1.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Bored chemist on 15/04/2009 19:29:18
According to this
http://www.bostonherald.com/news/international/general/view.bg?articleid=1081922
 you can see billions of miles already. Given the age of the universe, there isn't that much further to see.
A bigger eye would give, in principle, better optical resolution (ie the abillity to see two things close together as separate rather than as one blur) and also, for a giver size of retinal cell detecting the light it would alow a larger number of effective "pixels". Perhaps more usefull would be the ability to see better in low light conditions.
On the other hand, as has already been pointed out, eagles see better than us, and they have smaller eyes so we could improve things without making our eyes bigger.

Does anyone know what the typical angular resolution of the eye is and how it compares to the diffraction limit?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 15/04/2009 22:51:16
You had me worried there sophiecentaur.

Look at this picture



This was taken on my Nikon D300 12.3 mp and printed (slightly cropped)to 36" x 22"

If this had been taken on a 6mp camera, it would not be possible to print to this size without the diagonal lines being out of kilter. To get a print any bigger than this, I would need a camera with more pixels to its sensor.

I don't think your camera is diffraction limited. Did you use f100 as an aperture and a field of less than one degree?
Like I said, there's more to it than one simple statistic!
PS Have you got some dirt on your sensor? (Top left)
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 16/04/2009 01:35:22
Does anyone know what the typical angular resolution of the eye is and how it compares to the diffraction limit?
Very good question. It seems it's generally accepted as 1' (= 1/60 °) the angular resolving power of the human eye. With a pupil open of 4 mm the diffraction limit is just half of that value.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 16/04/2009 08:16:33
PS Have you got some dirt on your sensor? (Top left)

Yes, there was a speck of dust which I hadn't noticed until the print was done!

Details of shot:
Lens focal length 80mm ; f18 @ 1/1250sec ; ISO 200 ; re-colouring with Nikon Capture NX.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 16/04/2009 09:06:22

Not even Superman could do it,

I think you will find all of that a mere trifle to Superman; he can do anything!

As BC has cottoned on, I am really being hypothetical and not taking distortion into account. In practice, even over a relatively short distance atmospheric distortion would render ultra long vision pretty worthless. But, by the same token, our brain does account for and correct distortion caused by our fixed focus lens. For starters, the image projected onto the retina is upside down. Looking at an object a few cms away causes this effect:
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Ffarm1.static.flickr.com%2F157%2F374536567_ee1a164c88.jpg&hash=1f2add3c3ebd64ec438de3c4e2599242)
But our brain compensates for this and we see the object in a more natural way. Our brain also merges two different views to give us 3d vision.

The point I am making is that we do not need a bigger eyeball to see further. Again as BC pointed out, and as I said in a previous post, our eye can already see far distant objects. I cannot be sure of this, but I think V762 Cas (in Cassiopeia) is the furthest star from Earth visible to the naked eye. 15000 light years, I think is plenty far enough. Our eye's resolution, however, could be much improved with a sensor (retina) matching the quality of that of an eagle. Since the eagle's eyeball is the same size as a human eyeball, I see no need for a larger eyeball to improve our resolution.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 16/04/2009 09:08:47

The point I am making is that we do not need a bigger eyeball to see further....

Is that your final answer? [:)]
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 16/04/2009 09:12:01

The point I am making is that we do not need a bigger eyeball to see further....

Is that your final answer? [:)]

Yes.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 16/04/2009 09:13:55
And is that the final answer that'll put me out of my misery?
How about a show of hands, you may vote for or against Mr. Don_1.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 16/04/2009 10:54:53
PS Have you got some dirt on your sensor? (Top left)

Yes, there was a speck of dust which I hadn't noticed until the print was done!

Details of shot:
Lens focal length 80mm ; f18 @ 1/1250sec ; ISO 200 ; re-colouring with Nikon Capture NX.
It was a 'normal' photograph, as I suspected.
Hubble doesn't take 'normal' photos. It looks at a very small area in the centre of the 'normal' field and those 'few' Mpixcels are placed where they are wanted. An enlargement of a Hubble picture would appear glubby because of the optics. If you magnify any telescope image beyond a limit, you always get the imperfections of the optics grinning through. More sensors in the array would achieve nothing which the normal filtering of the image would achieve.
As for the original question, the ultimate limitation of 'seeing' something at a distance, boils down to Signal to Noise ratio. A large diameter is necessary and that implies a long focal length. There isn't a simple answer to this, at all.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 16/04/2009 12:46:46
So altogether, what do we need to take into consideration here?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 16/04/2009 15:23:15

Not even Superman could do it,

I think you will find all of that a mere trifle to Superman; he can do anything!

As BC has cottoned on, I am really being hypothetical and not taking distortion into account. In practice, even over a relatively short distance atmospheric distortion would render ultra long vision pretty worthless. But, by the same token, our brain does account for and correct distortion caused by our fixed focus lens. For starters, the image projected onto the retina is upside down. Looking at an object a few cms away causes this effect:
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Ffarm1.static.flickr.com%2F157%2F374536567_ee1a164c88.jpg&hash=1f2add3c3ebd64ec438de3c4e2599242)
But our brain compensates for this and we see the object in a more natural way. Our brain also merges two different views to give us 3d vision.

The point I am making is that we do not need a bigger eyeball to see further. Again as BC pointed out, and as I said in a previous post, our eye can already see far distant objects. I cannot be sure of this, but I think V762 Cas (in Cassiopeia) is the furthest star from Earth visible to the naked eye. 15000 light years, I think is plenty far enough. Our eye's resolution, however, could be much improved with a sensor (retina) matching the quality of that of an eagle. Since the eagle's eyeball is the same size as a human eyeball, I see no need for a larger eyeball to improve our resolution.
It's not about "distorsion", but about "diffraction limit", which cannot be overcome by *any* optical instrument, however perfect it could be. It's an impossibility of the *waves* of light, not a technical imperfection of the instruments.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 16/04/2009 15:28:44
So altogether, what do we need to take into consideration here?
Ask astronomers why they don't have reproduced the optical capabilities of an eagle's eye (or more) in a telescope with the same dimensions. It's not mostly about technological limitations, but mostly because of the diffraction limit.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 16/04/2009 17:51:23
I agree with you on the matter of diffraction, distortion, dust pollution, light pollution and all else which will prohibit clear vision over such a distance, regardless of the size of the sensor or the focal length of the lens. Your two 1mm spots on the Moon will be practically obliterated by the Airy Discs around them.

Geeze, I wish I'd never mentioned the Moon now. I was using it as an extreme example of how far the human eye can see.

The question is 'Would we be able to see further if we had bigger eye-balls?', not 'Could we see clearer (ie overcome distortion, diffraction etc.) if we had bigger eyeballs?'

I have been trying to say, you don't need a bigger eyeball to see any further, but an improved retina would make more distant objects clearer, as it does for the eagle. I don't think I have suggested that any improvement to our vision would overcome the obstacles, man made and natural, which limits *our* visual capabilities.

* Make that ANY visual capability.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 17/04/2009 00:25:10
So altogether, what do we need to take into consideration here?
Ask astronomers why they don't have reproduced the optical capabilities of an eagle's eye (or more) in a telescope with the same dimensions. It's not mostly about technological limitations, but mostly because of the diffraction limit.
With sufficient SNR, in hand, the diffraction limit isn't necessarily a limit. The Rayleigh Criterion is only a rule of thumb for conventional viewing. The real limitation comes from Mr Shannon (+edit)and this governs the amount of valid 'computer enhancement' possible.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 17/04/2009 01:09:47
...
The question is 'Would we be able to see further if we had bigger eye-balls?', not 'Could we see clearer (ie overcome distortion, diffraction etc.) if we had bigger eyeballs?'
And which is the difference? To be able to discern a farther object you need a greater resolving power.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 17/04/2009 01:11:51
With sufficient SNR, in hand, the diffraction limit isn't necessarily a limit. The Rayleigh Criterion is only a rule of thumb for conventional viewing. The real limitation comes from Mr Shannon (+edit)and this governs the amount of valid 'computer enhancement' possible.
Can you explain better?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 17/04/2009 01:12:52
...
The question is 'Would we be able to see further if we had bigger eye-balls?', not 'Could we see clearer (ie overcome distortion, diffraction etc.) if we had bigger eyeballs?'
And which is the difference? To be able to discern a farther object you need a greater resolving power.

Touché.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 17/04/2009 09:52:45
...
The question is 'Would we be able to see further if we had bigger eye-balls?', not 'Could we see clearer (ie overcome distortion, diffraction etc.) if we had bigger eyeballs?'
And which is the difference? To be able to discern a farther object you need a greater resolving power.

Precisely the point I have been making! Greater resolving power requires an improved retina, which does not necessarily require a bigger eyeball, as the eagle's eye demonstrates.

When I suggested that 386,242.5 megapixels would be required to see your two 1mm spots on the moon, this really was 'tongue in cheek'. There really is no way any eye or camera could pick out such fine detail over such a great distance and for a retina to have this number of megapixels (cones) our eyeball would probably need to be the size of our head.

I was assuming the question was 'relative to our current capability', not 'to an infinitesimal degree'. Relativity must be applied to this argument; the bigger eyeball must be capable of being housed in our existing head, not a head 10x bigger.

...
The question is 'Would we be able to see further if we had bigger eye-balls?', not 'Could we see clearer (ie overcome distortion, diffraction etc.) if we had bigger eyeballs?'
And which is the difference? ....

I can 'see' a bus at 100m; I can read it's route number at 100m; so can an eagle (if it could read). I can 'see' a bus at 250m, but I cannot read it's route number at that distance, an eagle can. I can 'see' a bus at 1km, but cannot read it's route number, neither can an eagle.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 17/04/2009 10:04:42
I can 'see' a bus at 100m; I can read it's route number at 100m; so can an eagle (if it could read). I can 'see' a bus at 250m, but I cannot read it's route number at that distance, an eagle can. I can 'see' a bus at 1km, but cannot read it's route number, neither can an eagle.
Well, I'm nearly convinced!
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 17/04/2009 11:03:19
With sufficient SNR, in hand, the diffraction limit isn't necessarily a limit. The Rayleigh Criterion is only a rule of thumb for conventional viewing. The real limitation comes from Mr Shannon (+edit)and this governs the amount of valid 'computer enhancement' possible.
Can you explain better?

This a signal processing topic. Imagine you have badly focused photo. You won't be able to read the number on the bus. If you know the characteristic of the optics, in detail, you can computer enhance the picture and get a better version of the number. This might, in a simple case, just involve the 'sharpen' control on your photo editor, which increases the contrast on edges. If you get it right, then you may see the number or you may see a wrong (look alike) number. Now imagine doing the same with a low light picture, in which the image has become speckled and 'noisy'. Even with the correct image enhancement, you can get the wrong bus number because of unfortunately placed speckles. Now imagine taking a series of low light photos, each with a different pattern of speckles, and averaging them to produce a new image with a lower level of speckledness. You then have a chance of getting the correct bus number - as with the original daylight picture.

Using a series of low light pictures (effectively using a longer exposure time), you have managed to increase the signal to noise ratio. The fundamental amount of information you can actually drag out of a picture actually depends upon the amount of speckle (or noise) on the picture - knowing details of the defects of your optics is, of course, essential.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 17/04/2009 22:06:41
Precisely the point I have been making! Greater resolving power requires an improved retina
or a greater lens, up to the diffraction limit. Arrived at that limit, an improved retina is meaningless.

Quote
, which does not necessarily require a bigger eyeball, as the eagle's eye demonstrates.

When I suggested that 386,242.5 megapixels would be required to see your two 1mm spots on the moon, this really was 'tongue in cheek'. There really is no way any eye or camera could pick out such fine detail over such a great distance and for a retina to have this number of megapixels (cones) our eyeball would probably need to be the size of our head.
Here I don't understand because it seems to me a ripetition of your previous mistake: even if a normal eye, or a device of that dimensions, had 1,000,000,000,000,000,000,000 Megapixels, you won't be able to discriminate those two points in the Moon.

Quote
I can 'see' a bus at 100m; I can read it's route number at 100m
Because the bus is bigger than its route number...
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 17/04/2009 22:11:32
This a signal processing topic. Imagine you have badly focused photo. You won't be able to read the number on the bus. If you know the characteristic of the optics, in detail, you can computer enhance the picture and get a better version of the number. This might, in a simple case, just involve the 'sharpen' control on your photo editor, which increases the contrast on edges. If you get it right, then you may see the number or you may see a wrong (look alike) number. Now imagine doing the same with a low light picture, in which the image has become speckled and 'noisy'. Even with the correct image enhancement, you can get the wrong bus number because of unfortunately placed speckles. Now imagine taking a series of low light photos, each with a different pattern of speckles, and averaging them to produce a new image with a lower level of speckledness. You then have a chance of getting the correct bus number - as with the original daylight picture.

Using a series of low light pictures (effectively using a longer exposure time), you have managed to increase the signal to noise ratio. The fundamental amount of information you can actually drag out of a picture actually depends upon the amount of speckle (or noise) on the picture - knowing details of the defects of your optics is, of course, essential.

You mean that, given enough time and computational power, you could get a detailed picture of an alien's garden in a planet 10 billions of light years from here, with a conventional telescope?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 17/04/2009 22:32:26
That's effectively, what Shannon says, yes.
But, of course, the numbers count! It would take a huge amount of time because the SNR could only  be high enough with a very very small bandwidth (i.e. long observation time).
Already, they use 'good' images of (angularly) nearby stars to characterise the instantaneous aberrations due to atmosphere etc. and cancel them out to produce much better images of faint objects.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: LeeE on 17/04/2009 23:17:40
This a signal processing topic. Imagine you have badly focused photo. You won't be able to read the number on the bus. If you know the characteristic of the optics, in detail, you can computer enhance the picture and get a better version of the number. This might, in a simple case, just involve the 'sharpen' control on your photo editor, which increases the contrast on edges. If you get it right, then you may see the number or you may see a wrong (look alike) number. Now imagine doing the same with a low light picture, in which the image has become speckled and 'noisy'. Even with the correct image enhancement, you can get the wrong bus number because of unfortunately placed speckles. Now imagine taking a series of low light photos, each with a different pattern of speckles, and averaging them to produce a new image with a lower level of speckledness. You then have a chance of getting the correct bus number - as with the original daylight picture.

Using a series of low light pictures (effectively using a longer exposure time), you have managed to increase the signal to noise ratio. The fundamental amount of information you can actually drag out of a picture actually depends upon the amount of speckle (or noise) on the picture - knowing details of the defects of your optics is, of course, essential.


There's a bit of a difference between enhancing an out-of-focus image and a low-light image.  As you say, if the characteristics of the optics are known it's relatively simple (although time consuming in practice) to model the lens and arrive at a limited set of sources that could have produced the blurred image.  With a low-light level image though, you've lost dynamic range and this can't be derived from the lens optics.

With the blurred image then, the data isn't lost but misplaced, but with a low-light level image the data is lost.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 17/04/2009 23:38:32
There are two factors - the signal energy and the noise energy. If the signal energy is big enough wrt the noise energy, you can reconstruct the signal. The dimmer the picture is, the longer you need to look, to get enough signal. The higher the noise level is, the narrower bandwidth you need. Given long enough, the snr can be made arbitrarily high.
The "out of focus image" was only an example. The diffraction due to limited aperture is the bottom line with astronomy.
Read the basics of Shannon's theory; it's heavy going but it's the basis of all information transfer situations.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 18/04/2009 02:07:19
the signal energy and the noise energy. If the signal energy is big enough wrt the noise energy, you can reconstruct the signal....the narrower bandwidth you need. ...the snr
...The diffraction due to limited aperture is the bottom line with astronomy...Shannon's theory.

Okay, so how does all this relate to eye-balls and seeing further? Does this answer the question?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 18/04/2009 13:20:25
Precisely the point I have been making! Greater resolving power requires an improved retina
or a greater lens, up to the diffraction limit. Arrived at that limit, an improved retina is meaningless.

So you say an eagle, with a similar lens but a superior retina to ours, can see no better than a human?

Yes, a telescopic lens would be better for seeing over long distances, but such a lens requires more than one element. Our lens & that of an eagle (and cornea) is not a 'lens' in the sense of an optical camera or tele/microscope lens. These contain a number of fixed and moveable elements, our 'lens' is a single element which would be better described as a wide angle windscreen.


, which does not necessarily require a bigger eyeball, as the eagle's eye demonstrates.

When I suggested that 386,242.5 megapixels would be required to see your two 1mm spots on the moon, this really was 'tongue in cheek'. There really is no way any eye or camera could pick out such fine detail over such a great distance and for a retina to have this number of megapixels (cones) our eyeball would probably need to be the size of our head.
Here I don't understand because it seems to me a ripetition of your previous mistake: even if a normal eye, or a device of that dimensions, had 1,000,000,000,000,000,000,000 Megapixels, you won't be able to discriminate those two points in the Moon.

Isn't that what I said?


I can 'see' a bus at 100m; I can read it's route number at 100m
Because the bus is bigger than its route number...


I presume you intended this quote to be:
Quote
I can 'see' a bus at 250m, but I cannot read it's route number at that distance

To which you argue
Quote
Because the bus is bigger than its route number...

Yes, I can see the bus, but cannot discern the detail which my eye is incapable splitting into a fine enough image, but the eagle can do this, because it's retina has more cones and can, therefore, break down the image into smaller 'pixels' allowing the processor (the brain) to interpret the image in finer detail.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lightarrow on 18/04/2009 15:29:45
So you say an eagle, with a similar lens but a superior retina to ours, can see no better than a human?
You wrote:
Quote
Greater resolving power requires an improved retina
and in my reply I wanted to point out that this answer is correct only *if you haven't already reached the diffraction limit*. I hope we can agree on it.

Quote
Yes, a telescopic lens would be better for seeing over long distances, but such a lens requires more than one element. Our lens & that of an eagle (the cornea) is not a 'lens' in the sense of an optical camera or tele/microscope lens. These contain a number of fixed and moveable elements, our 'lens' is a single element which would be better described as a wide angle windscreen.
But even if we had in our eyes moving parts as in a telescope, you could never be able to see those two points on the Moon.

Quote
Yes, I can see the bus, but cannot discern the detail which my eye is incapable splitting into a fine enough image, but the eagle can do this, because it's retina has more cones and can, therefore, break down the image into smaller 'pixels' allowing the processor (the brain) to interpret the image in finer detail.
Probably it's true (even if I sincerely don't know what and how eagles actually see) and you are right; what I intended is that, even with infinite pixels, you will reach a limit where you can still see the bus, but not the number, because of diffraction.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 18/04/2009 22:52:20
The way the brain deals with images is quite complex. There is some spatial filtering (interconnections between adjacent sensors), apparently, which deals with some aberrations. Optically, the eye lens is not good but the overall performance is helped a lot by the filtering in the retina.

With an 'ideal' circular aperture, the  (spatial) impulse response (diffraction) is sinx/x and with appropriate inverse filtering, you can improve significantly on the half-power dip between two point sources (stars, for instance). But this inverse characteristic has the effect of magnifying the effect of noise so, to improve on the rayleigh criterion, you need progressively longer and longer exposure times. Worth it if you really need to resolve two objects but academic if you are just looking down your telescope!

It is really unfair to try to discuss performance of biological systems in terms of 'simple' Engineering / Physics. Evolution finds a compromise between cost and benefit. No animal will have 'better' eyesight than it needs. The Eagle is such a specialised feeder that it is susceptible to all sorts of environmental pressures which a Human can deal  with in ways other than by having 'better' eyesight. With Nature, it's a matter of compromise, always; with Technology, you just chuck more money at it.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: LeeE on 18/04/2009 23:19:22
There are two factors - the signal energy and the noise energy. If the signal energy is big enough wrt the noise energy, you can reconstruct the signal. The dimmer the picture is, the longer you need to look, to get enough signal. The higher the noise level is, the narrower bandwidth you need. Given long enough, the snr can be made arbitrarily high.
The "out of focus image" was only an example. The diffraction due to limited aperture is the bottom line with astronomy.
Read the basics of Shannon's theory; it's heavy going but it's the basis of all information transfer situations.

I read up on Modulation Transfer Function a long time ago, when I was still doing a lot of photography, but hadn't heard of Shannon's theory.  One day, when I'm in the mood I'll have a read of it.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 19/04/2009 21:22:15
He IS the Daddy!
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 19/04/2009 23:25:06
MTF is the equivalent of frequency response for HiFi. It isn't the whole story but is a good start.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 20/04/2009 01:11:11
Seeing as we've all come to some sort of an agreement, any last words to wrap up this thread?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 20/04/2009 08:34:37
So you say an eagle, with a similar lens but a superior retina to ours, can see no better than a human?
You wrote:
Quote
Greater resolving power requires an improved retina
and in my reply I wanted to point out that this answer is correct only *if you haven't already reached the diffraction limit*. I hope we can agree on it.

Quote
Yes, a telescopic lens would be better for seeing over long distances, but such a lens requires more than one element. Our lens & that of an eagle (the cornea) is not a 'lens' in the sense of an optical camera or tele/microscope lens. These contain a number of fixed and moveable elements, our 'lens' is a single element which would be better described as a wide angle windscreen.
But even if we had in our eyes moving parts as in a telescope, you could never be able to see those two points on the Moon.


Yes & yes.

It is suggested (based on observation) that eagles can define objects at a distance of 2.24 times greater than that of a human.

A larger eyeball would not necessarily increase the distance at which an object can be observed. A wider pupil would allow more light into the eye, giving improved vision in low level light, as is the case for nocturnal animals such as owls and cats. An increased number of cones on the retina would give improved definition by breaking down the image into more precise information, allowing the brain to create an image of a higher clarity, thus making parts of that image, which are indefinable with the number of cones our retina currently has, definable. But ultimately, the distance at which an object can be defined is not dependant solely on the size and/or quality of the eye. Since the eye is a receiver, it can only translate the light it receives into a signal which the brain converts to an image. The distances at which we can define objects are equally governed by the constraints of the physical properties of light as it travels through space and/or our atmosphere and its passage through our cornea and the saline wash keeping it clean. During its passage from object to eye, dust, water vapour, strong gravitational fields, our cornea and its ‘screen wash’ can distort and diffract the light. An improved eye would simply produce a clearer image of that distorted and diffracted light; it would not be able to reconstitute the light into its original undistorted and un-diffracted pattern.

How's that?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 20/04/2009 08:58:33
Doesn't the digital camera situation say it all?

The best compact cameras with small sensor areas and small lenses are never as good as the best SLRs with larger sensors and larger lenses. `the resolution is better because there is more room for sensors and the noise performance is better because the sensors area is greater.

Why do you think all the 'best' quality photos are taken on large format film cameras?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 20/04/2009 09:00:28
Come on Doris, stop talking in riddles! [:)]
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 20/04/2009 09:11:05
A larger eyeball would not necessarily increase the distance at which an object can be observed. A wider pupil would allow more light into the eye, giving improved vision in low level light, as is the case for nocturnal animals such as owls and cats. An increased number of cones on the retina would give improved definition by breaking down the image into more precise information, allowing the brain to create an image of a higher clarity, thus making parts of that image, which are indefinable with the number of cones our retina currently has, definable. But ultimately, the distance at which an object can be defined is not dependant solely on the size and/or quality of the eye. Since the eye is a receiver, it can only translate the light it receives into a signal which the brain converts to an image. The distances at which we can define objects are equally governed by the constraints of the physical properties of light as it travels through space and/or our atmosphere and its passage through our cornea and the saline wash keeping it clean. During its passage from object to eye, dust, water vapour, strong gravitational fields, our cornea and its ‘screen wash’ can distort and diffract the light. An improved eye would simply produce a clearer image of that distorted and diffracted light; it would not be able to reconstitute the light into its original undistorted and un-diffracted pattern.

How's that?

Hmmm...not bad, not bad at all.
But really! Strong gravitational fields! Is that necessary? [:D]
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 20/04/2009 09:32:33


Hmmm...not bad, not bad at all.
But really! Strong gravitational fields! Is that necessary? [:D]

OK, that would be in dispute, so you can disregard if you wish.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 20/04/2009 16:07:35
Come on Doris, stop talking in riddles! [:)]
What have I got in my pocket?
Precious!
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 21/04/2009 00:56:17
Your wallet?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 21/04/2009 02:01:20
Alright, getting back on track.
Are we still in some sort of disagreement here or what?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 21/04/2009 14:05:00
No. I'm just being silly.  [:-\]
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 21/04/2009 14:09:13
So could you please give me your final answer?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Don_1 on 21/04/2009 15:19:43
I'm happy with the outcome.
Title: Would we be able to see further if we had bigger eye-balls?
Post by: lyner on 21/04/2009 19:44:15
Bigger is potentially better. Final answer.
£k64 prize?
Title: Would we be able to see further if we had bigger eye-balls?
Post by: Chemistry4me on 22/04/2009 00:44:30
As this thread drifts into oblivion....
Okay Doris, you can have the prize. (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fbestsmileys.com%2Fclapping%2F5.gif&hash=84082ae1375d85f65239829d6b135af8)(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fbestsmileys.com%2Fclapping%2F5.gif&hash=84082ae1375d85f65239829d6b135af8)