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It seems the extra crosses only appear when shooting into the sun , with plenty of flare ...
So consistent with an in-camera phenomenon , rather than post-production fakery.
Unless you can find extra crosses in a flare-free NASA moon image the puzzle is solved
Quote from: RDIt seems the extra crosses only appear when shooting into the sun , with plenty of flare ...Does it really seem that way to you RD?
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Yes it does seem to be the case as the only examples of images with duplicate crosses I've seen are images which have conspicuous flare, (see the NASA links in my reply #20 ).
If you can find a NASA moon image with duplicate crosses which does not have flare it would be evidence the duplicate crosses are not an in-camera phenomenon caused by flare, as I allege.
If the extra crosses are generated in post-production fakery there's no reason they should only occur in images with flare , (which will be a minority of the photographs taken). If you are correct and the extra crosses are an artefact of image manipulation there should be plenty more of them in images without flare. Good luck finding them.
The way things seem is not the empirical method, check these out some time man.... http://en.wikipedia.org/wiki/Empirical_research
Empirical evidence ... is a source of knowledge acquired by means of observation or experimentation
Empirically {by observation} the double crosses only occur on images with flare, so consistent with an in-camera phenomenon , rather than a product of image manipulation which would not be specific to images with flare.
Also your illustrations in reply #24 do not show a surface curving in two planes, (similar of arcs. A lens-shaped surface is required somewhere to create the extra crosses which have radial-[pincushion]-distortion , there is such a thing in the camera.
The mechanism : the image of the very bright flare spot on the Reseau plate in the camera, (which has black crosses on it) , is reflected by a rear element in the lens, back onto the film creating a second set of black crosses which have radial [pincushion] distortion.
The reflected image of the black crosses is visible because they are dark lines in a patch of bright fog created by the reflected flare spot , (think Bat-Signal).
[ The contrast in the double-cross examples is very low consistent with fogging : the original orthogonal cross is washed-out-grey rather than opaque-black like the typical appearance of these "fiducial" marks].
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Your diagram above has the cross aligned on the optical axis of the lens.In that special-case the effect I’ve described would not produce an obvious second cross :with the cross on the optical-axis, the second cross, via reflection in the lens,would have the same centre as the first cross and would not suffer any curvature,( it would just be slightly bigger than the first cross, but would be perfectly aligned on top of it ).
With radial-distortion, like pincusion distortion , the further you go from the optical-axis the worse it becomes.
If you try redrawing the diagram as if the cross was about halfway between the centre of the film and a corner of the frame , (as in AS14-66-9306 ) , maybe you'll see mine is a valid hypothesis ...
Such reflections from the Reseau plate , to the rear of the lens , and back through the Reseau plate onto the film, will occur every-time a photo is taken with this camera. Each reflection loses ~99%, so the double-reflection which gets to the film is approx 1/10,000* the original brightness : usually too dim to register on the film, and only becomes visible when that part of the image is very bright, like a flare-spot from the sun which is still visible even after it's brightness has been reduced by a factor of 10,000.
It doesn't matter how things are arranged ...
... hypothesis involving some magical unknown optical mechanism? ... Where's an example?
It perfectly matches observations and appears precisely the same as what's seen in the photograph....
... a strong behavioural correspondence between the target system (the NASA photograph) and the source system (the replication) was instantly recogizable ....
Not a strong enough correspondence....
....on your re-creation the duplicate (shadow) crosses are all displaced in the same direction, whereas on the photo the extra crosses are displaced radially, (the curved crosses are all outside the green square I have drawn by joining up the orthogonal crosses).
A lens-like curved surface is required to produce a radial displacement, (and to produce crosses made of arcs). If you could bend the transparency into lens-like bulge that would produce a pattern which corresponded with the photo, but film is too rigid to do that, ( and there is already a lens-like surface in the camera : the lens ).
... I don't foresee any problem (yet) tightening up the resemblance in the next replication....
I'll tell you what I'll bear in mind ...
... your still going on about the so called "lense flare effect" as if it's fact when it's really just unsupported untested unverifiable fantasy...