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File: microdot.png (378 KB, 825x511)
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Is pic related true?I can't find any further info on this technique and I don't currenty have access to a film camera.
Has anyone here ever made microscopic photos?If so, what technique did you use?
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You would need a high resolution copy film to make that readable. The technical pan knockoff that Rollei sells might work.
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>>3479263
Are you a chinese spy with a retro addiction?
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>>3479263
Yes microdots were defiantly a thing, they only really work well with high contrast subjects such as black text on white paper. As stated very low ISO copy film was used for this process. To make one there is nothing that complicated to it.
Set up a white board and put your negative on there. Then take a photo of it. There are other processes including reducing lenses.
Look into microfilm/microfiche and the reduction processes as well as the lith/copy film used.
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>>3479263
Not microdots but I did long ago some Fresnell zone plates on litho film. I cut suitable pieces and stuffed those in film camera with a 50/1.7 (Pentax-M). Getting the size right and developing film enough but not overdeveloping took some tries. Easily resolved pixels of http://www.mrpinhole.com/zp.php prints when few mm diameter on film.
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>>3479272
>>3479352
>>3479946
>>3479953
thank you guys I found a film camera and I will try it out
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File: a1QQKdR_460s.png (215 KB, 460x320)
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>be spy
>take full frame pictures of classified documents on film roll - fast, easy.
>have to have specialised equipment set up somewhere with exact distances and focal lengths and precise cutouts and lighting and magnifiers and and and .... - slow, expensive, must be placed somewhere permanent like a safe house
>guard checking everyones shit between the general's room and the exit to my safe house.
>well fuck.

How would this have been useful or practical? A dot is useful because it might be hidden in plain sight amongst other stuff on a picture if it was developed by spy-checkers, or it was useful because you might be able to fit *many* such dots on a single frame meaning useful compression of vital data in a small space but I fail to see how spies even got to the point where they were able to smuggle the important shit to where their equipment to do this was in the first place.

And if they could, why not just send the fucking normal roll of full frame pictured documents back to base as is? You can smuggle the obvious stuff out, why go through more trouble? Am I missing something here?
I cannot set up and then pack away all this equipment in the space of 5 mins in a high security area for the sake of miniaturization.
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>>3480172
All the things needed for making microdots can be acquired and kept legally even in hostile countries.It's like with invisible inks; in both world wars and during the Cold war,both sides developed very hard to detect invisible inks, but the classics (lemons,milk,white vinegar etc.) were still the most popular. They were relatively easy to detect,but they could be bought in enemy countries without raising suspicion.
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>>3480172
Weren't they making the dots back home and then transferring them to select people in secrecy?

>Oh hey Donny, thanks for the pen, I totally lost it haha wink wink
>No problem Vladdy, best pen ever. Absolutely incredible. Absolutely incredible communications technology, top of the line.
>Audience applause
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if this works, then does this mean that digital sensors are decades behind film in terms of resolving power?
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>>3480322
No is the short answer, While there have been differences to lens design to accommodate the cells of photosensors the designs are largely the same in terms of resolving power. What makes a difference here is the very slow film processed in very high contrast methods.
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>>3480324
sure, in the general case. I guess I am curious about how well this tech would fare for landscapes, for example-- the details would be incredible, but what are the downsides?
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>>3480328
Look into stuff like true monochrome film (only blue sensitive) on glass plate. Extreme fine grain, can hit the limits of student lenses but you get terrible color representation. To the best of my knowledge you would also have to make it yourself i am unaware of commercial products. Also the ISO would be something like 0.2 depending.
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>>3480331
ah interesting. it seems like this sort of thing would be okay for b&w then? anyways thanks anon
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>>3480328
>the details would be incredible, but what are the downsides?
Extreme contrast and limited dynamic range. Special low contrast developers needed to get something usable.
Point is, very few lenses are *that* good, they cost fortune, and you're bound to a tripod with mirror lockup to exploit the extra potential.
At this point, might as well shoot a 100$ medium format lens over a 1k$ 35mm format one, and get better resolution with a normal film.
Also film size and cost scales linearly, very few people would obsess over maximum sharpness and special films on a format, when they can just cut a bigger sheet of film and get better results this way.



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