I've seen plenty of references to using enlarger / photoscanner / machine vision / photoprinter etc lenses for macro work but I can't find anything on using photocopier lenses in this way.
I admit - in my considerable ignorance - that I didn't know that photocopiers even used lenses (what for?) but from cross-referencing the some of the ones I've seen on eBay with the manufacturers engineering manuals, it seems that higher end office copiers do use them.
Those that I've seen are mainly spares from scrapped systems and come as a unit with metal mount, CCD board etc and seem to be priced from GBP 10 / US$ 15 or so.
Examples:
https://www.ebay.co.uk/itm/Ricoh-Scanne ... SwmtJXV38X
https://www.ebay.co.uk/itm/KONICA-MINOL ... SwKAFdrjyR
https://www.ebay.co.uk/itm/Xerox-604K18 ... SwnLdWqHjG
The lens look decent candidates and given that these are for very high cost units mostly on long term leases, I assume that they lenses will be variants on existing industrial lenses and reasonable quality for their intended purpose?
Have they been looked at for macro work?
I hope this isn't nonsense and that my limited forum and Google searching hasn't missed the blindly obvious.
Thanks
Photocopier Lenses For Macro?
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rjlittlefield
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Those lenses serve to project an image of the original paper onto a "line scan sensor" that is like a single row of pixels on a camera sensor. Some mechanical scanning process then moves that row across the paper to incrementally construct a high resolution digital image of the entire page. On the output side there's a laser printer that transfers the digital image back to paper, so the whole thing is like a scanner and a laser printer integrated into one big box.
The lens will be optimized to cover an image circle whose diameter is equal to the length of the line sensor, and a subject circle whose diameter is equal to the width of the paper to be scanned. This translates to something like 0.1X magnification. So, the lens will be rather like an enlarger lens in reverse, with no adjustable diaphragm.
For macro use, you would do best to reverse the photocopier lens so that whichever side normally faces the small sensor would face the small subject instead.
In that reversed orientation, the lens by itself would be optimized for something like 10X magnification, but only over a very large sensor like 8x10 sheet film. If used with a small sensor at 10X, it won't have an aperture wide enough to give good resolution, and if placed on less extension to give say 2X, it will not be well corrected because the focus distances are so much different from its design point.
Image quality would improve if you "stack" the photocopier lens, reversed, in front of a ordinary camera lens that is focused at infinity. In that configuration, the magnification will be the ratio of the focal lengths (rear/front).
Note that the lens for a photocopier and the lens for a film scanner are optimized for very different situations. The film scanner will be optimized for something around 1:1 on a small sensor, which makes it suitable for use by itself on a small sensor DSLR or mirrorless body.
--Rik
The lens will be optimized to cover an image circle whose diameter is equal to the length of the line sensor, and a subject circle whose diameter is equal to the width of the paper to be scanned. This translates to something like 0.1X magnification. So, the lens will be rather like an enlarger lens in reverse, with no adjustable diaphragm.
For macro use, you would do best to reverse the photocopier lens so that whichever side normally faces the small sensor would face the small subject instead.
In that reversed orientation, the lens by itself would be optimized for something like 10X magnification, but only over a very large sensor like 8x10 sheet film. If used with a small sensor at 10X, it won't have an aperture wide enough to give good resolution, and if placed on less extension to give say 2X, it will not be well corrected because the focus distances are so much different from its design point.
Image quality would improve if you "stack" the photocopier lens, reversed, in front of a ordinary camera lens that is focused at infinity. In that configuration, the magnification will be the ratio of the focal lengths (rear/front).
Note that the lens for a photocopier and the lens for a film scanner are optimized for very different situations. The film scanner will be optimized for something around 1:1 on a small sensor, which makes it suitable for use by itself on a small sensor DSLR or mirrorless body.
--Rik
Hi Ray,
among more than 200 enlarger / photoscanner / machine vision / photoprinter lenses tested for MTF resolution and CA, I had couple of photocopier lenses on test with very different performances. But they did share few common characteristics: they all have pretty long focal lengths, mostly between 100 and 200 mm. Apertures were anything between f/2.8 and f/8, CA was mostly badly controlled. All of that makes them below average performers as taking lenses but OTOH some of those were very good tube lenses. Of course, you'll have to buy first then test and hope for above average performance.
Unless you are ##### crazy freak like myself (and at least one other forum member here) ready to hunt in total darkness and spend a fortune on unknown lenses no one tried, I wouldn't recommend this sport!
It is wiser to stick to well proven lenses that are notorious for good performance.
Best,
Miljenko
among more than 200 enlarger / photoscanner / machine vision / photoprinter lenses tested for MTF resolution and CA, I had couple of photocopier lenses on test with very different performances. But they did share few common characteristics: they all have pretty long focal lengths, mostly between 100 and 200 mm. Apertures were anything between f/2.8 and f/8, CA was mostly badly controlled. All of that makes them below average performers as taking lenses but OTOH some of those were very good tube lenses. Of course, you'll have to buy first then test and hope for above average performance.
Unless you are ##### crazy freak like myself (and at least one other forum member here) ready to hunt in total darkness and spend a fortune on unknown lenses no one tried, I wouldn't recommend this sport!
It is wiser to stick to well proven lenses that are notorious for good performance.
Best,
Miljenko
All things are number - Pythagoras
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Macro_Cosmos
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I have that 10.42 pounds lens. Seller is a nice (can be a bit grumpy) feller, send him an offer.
The lens covered FX and centres are really good. Corners are fuzzy.
bigger: https://flic.kr/p/2dwdncC
It uses this sensor:
https://flic.kr/p/PPiWtz
The lens covered FX and centres are really good. Corners are fuzzy.
bigger: https://flic.kr/p/2dwdncC
It uses this sensor:
https://flic.kr/p/PPiWtz
Thanks for the lucid explanations. Glad that my basic idea wasn't too mad and not surprised that others have long since tried and mostly discounted it. Shame given the limited supply of quality lenses for legacy uses like printing from film.
I'd love to have the time, cash and especially the expertise to be an exotic lens freak... but those positions are filled here already!
For now I focus on trying to get half decent results from the kit I have.
Daniel - thats a lovely looking set of tools. Hex envy.... Although the old lens unit is pretty cheap, the shipping on ebay from the US to here in the UK is absurd - 4x the cost of the part. If I see something cheap and local, might be tempted.
I'd love to have the time, cash and especially the expertise to be an exotic lens freak... but those positions are filled here already!
For now I focus on trying to get half decent results from the kit I have.
Daniel - thats a lovely looking set of tools. Hex envy.... Although the old lens unit is pretty cheap, the shipping on ebay from the US to here in the UK is absurd - 4x the cost of the part. If I see something cheap and local, might be tempted.