Digital contact print/ lowering the bar

[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.