Digital contact print/ lowering the bar

[Jay DeFehr]

If there was a technology that allowed the use of a LF sized sensor that was capable of producing B&W film/contact print-like quality at 1:1 reproduction sizes, would you be interested?

The above represents a very significant lowering of the bar relative to current photographic image sensor technology, and a potential separate branch of the evolutionary tree. Something along these lines might be within the realm of current printed sensor technology. It is conceivable that such a technology could deliver much improved sensitivity, dynamic range, and economy compared to film.

A more evolved technology could produce sensors so cheap they function like Polaroid instant material, but instead of getting a positve print and a negative, you'd get a positive print and a digital file, and both could be re-writable.

But if the lowering of the technology bar meant these images are limited to B&W at 1:1 reproduction sizes, would you be willing to accept that limitation? If so, how much might you be willing to pay for the technology? If an 8x10 sensor cost $2000 and had a life expectancy of 1 year, would you be interested?

[Daniel Stone]

Personally, I shoot under $2000 worth of 8x10 and 4x5 film in about 2yrs worth of shooting. Not much IMO, compared to some others. Most of my 8x10 film I buy in "bulk" from ebay listings, or stores closing their doors up.

But I'm very choosy about what I want to shoot these days. The processing costs(for color), and time to scan(which I'm doing now myself)/print or proof all that film, just to see what I get(for negatives) takes a lot of time. Sometimes I go out with full intent of exposing all 5 film holders in my holder bag, only to return with 5 holders and no exposed film. If the light isn't right, I don't shoot. Period... That's one thing assisting has taught me ;)(and seeing others make that mistake to shoot under adverse/suboptimal conditions only to kick themselves later).

Take one of these:

http://www.aphotoeditor.com/2011/08/23/mitchell-feinbergs-8x10-digital-capture-back/

and scale it up

-Dan

-Dan

[Jay DeFehr]

Hi Dan,

The economics are complicated, and probably highly variable among individual photographers, but we can make some hypothetical comparisons. $2,000 would buy something like 1 sheet of TXP /day for a year. The TXP would offer advantages to my hypothetical; chiefly the ability to make much larger prints, but also including being power independent, and maybe some others I'm not thinking of. Potential advantages to my hypothetical technology could include any or all of the following:

Unlimited number of potential exposures over the lifetime of the device.
No film processing
No film scanning
No fogging
No need for changing bag/darkroom
No need for multiple film holders/backs
Instant feedback for precise exposure/focus/composition evaluation
Increased sensitivity
Increased dynamic range

Would the above adequately compensate for a 1:1 reproduction ratio?







The Maxback is RGB color, which adds a lot of complexity/expense. Limiting to B&W represents a significant lowering of the technical bar by making sensor printing technology a viable option, and as the Color from B&W Film thread illustrates, there's more than one way to skin a cat.

I'm wondering how many LFers use LF for making large prints, and how many would be content to make prints the size of their camera formats.

[vinny]

Unlimited number of potential exposures over the lifetime of the device.
No film processing
No film scanning
No fogging
No need for changing bag/darkroom
No need for multiple film holders/backs
Instant feedback for precise exposure/focus/composition evaluation
NO FUN!

[Richard M. Coda]

Unlimited? Nothing man-made, especially electronic, has that kind of lifespan. It WILL break or fail... just a matter of how soon.

[Jay DeFehr]

Vinny,

To each, his own. Thanks for posting.


Richard,

I qualified unlimited with over the lifetime of the device. In my first post I specified a device lifetime of one year.

[Nathan Potter]

Jay, try to check out digital xray panels, especially those sensor panels that are intended to be a direct replacement for old xray film. A number of medical hardware companies are supplying these in various solid state technologies. They can be had up to very large sizes (those for chest xray for example). I found a few with sub 100 um pixel size a while back. ASA for visible light would be quite low but I might guess that the amorphous semiconductor type without scintillator might be a good candidate for visible light.

These already exist. I think they might be in the 3000 to 10,000 buck range.

The problem with moving from xray energies to visible light energies involves a reduction in quantum efficiency due to the reduced absorption of light photons compared to xray photons.
Light is absorbed in the surface of the semiconductor vs xrays which are absorbed in the bulk, so xrays can generate larger quantities of hole/electron pairs, hence higher current output. There also may be some bandgap engineering done with the semiconductor which could improve the responsivity to xrays but not to visible light - don't know in detail about this.

Probably worth becoming more informed about this technology. For B&W only for now.

Nate Potter, Austin TX.

[Jay DeFehr]

Hi Nate,

I wasn't aware of the X-ray sensors, or their potential for visible light imaging. I'm thinking about the emerging technology of printed electronics at the nano-scale, as discussed here:

http://nano.eecs.berkeley.edu/publications/Advanced_Materials_2009_NWprinting.pdf

and here:

http://www.extremetech.com/extreme/101763-parc-thinfilm-unveil-first-printed-flexible-cmos-computer-circuit



I don't think anyone is directly working on the specific kind of imaging system I'm suggesting here, but I don't think that really matters. I think this kind of imaging system could fall out of the technology as an unanticipated application. In fact, the technology might exist now, but no one is interested in this application. It might be assumed everyone wants smaller, lighter cameras with more powerful sensors instead of larger, heavier cameras with relatively crude sensors. And they might be right, if most LFers are like Vinny.

[Bill Burk]

Sounds electrostatic. For it to be interesting to me 1:1 would have to be 1200dpi or better and have amazing gradation. But at that rate, it would be enlargeable.

[Jay DeFehr]

Bill,

Why 1200 dpi? And if 1200dpi @ 1:1 is your minimum quality standard, how would it be enlarge-able? My question refers to the hypothetical situation in which IQ is equal to contact printed film, meaning able to make a comparable print at 1:1, but no more. That means it would have gradation equal to contact printed film.

[jnantz]

hi jay

if i had a lot of money to spend,
and i shot inexcess of $3K film / year
i would be very interested in technology like that
but i am happy for the time being using
expired film and paper to capture images on.

you mention the lifespan would be about a year ...
would you have some way of determining how many 'scans"
have gone through it, seeing one would be able to do proofing scans
/ pre exposure scans with it? would one have to be tethered to a computer?
or would it be able to dump the images onto a variety of 10$ thumb drives and stitched
in a light room afterwards ?


thanks !
john

[Jay DeFehr]

Hi John,

This is purely theoretical technology based on my speculations about a much more general and rapidly evolving technology, so specifics are also hypothetical. That being said, printed memory is another aspect of printed electronics technology, and I can imagine a device similar in dimensions to a traditional film holder, inclusive of sensor, memory, and display, but that's at the mature end of what I'm imagining. What I'm asking about in this thread is how low we can set the bar for an acceptable technology. To be clear, this wouldn't be a scanning back, but more similar to a CMOS-type sensor. I set the lifetime of the device to 1 year to simplify the economics and emphasize the technology is meant to be cheap. My $2000 figure is based on the cost of one sheet/day of TXP for one year, and an attempt to determine what we consider value given the limitations of the technology. So, let's imagine we can preview the captured image on our smart phones, but we'd need a portable memory device to store the image files. How large a file is required to make a high quality 8x10 print? 20 MB? Memory is getting smaller and cheaper by the minute, so I don't really see this as a problem. Remember, we've limited the IQ to that required to make a high quality print at 1:1 reproduction size, so file sizes are not anywhere near what they would be for a drum scan of the same size film. One thumb drive should provide a lot of shooting capacity.

[paulr]

600ppi would even be more than adequate. Meaning, more than what any human being could detect in a 1:1print. With enough MTF in the 1 to 5 lp/mm range, you could create a greater sense of detail and sharpness than with a film contact print, even at 360ppi. 600ppi would provide insurance against aliassing of diagonal lines. I've done this kind of printing several times and compared side by side.

But I don't understand the appeal of a contact print sensor, unless you're specifically inclined to the depth of field effects of big film/long lenses. With silicon you pay by the square millimeter, so it's beneficial to squeeze as much resolution as possible out of a small piece before inching bigger.

[Jay DeFehr]

Hi Paul,

Thanks for the sensible analysis of what's really needed for the job. The appeal of a big sensor is that it allows LF photographers to remain LF photographers, even if everyone stops making film, and without resorting to WPC. Based on the discussion at this forum, it seems the choice of LF for many/most is not based primarily on a desire to make larger prints, and many 8x10+ users contact print only, and most shoot primarily/only B&W. If we're realistic about our motivations and requirements, it could open the door to technologies we might not recognize as viable alternatives to film, and to the kinds of silicon sensors used in typical digital imaging systems. Printed sensors on flexible substrates is one potentially viable alternative, among many others we might not consider if set the bar at the level of film or a 28mp FF CMOS sensor. These technologies are not being developed for LF imaging applications, but if adopted for that use, they will evolve in that application.

As LF film becomes both less available and more expensive, LFPs should be more open to experimenting with new, sub-optimal, non-film technologies in the same way some are willing to experiment with non-pictorial, sub-optimal films, like X-ray films.