Using sunprint paper in a camera?

fabulousrice · Feb 19, 2021

Has anyone had successful results using a sunprint paper such as this in a camera?
I tried a few times and failed. From what I gather you have to use a camera whose lens isn't UV coated. So either one of my Holgas that I would have to somehow block the shutter or one of the very old cameras I have whose glass might not have been coated during production.
Curious if anyone's tried and succeeded...

Donald Qualls · Feb 19, 2021

Two problems with cyanotype (which is what sunprint paper is): as you note, it's sensitive to UV only. Second problem is the extremely low sensitivity. Equivalent ISO speed would be much less than 1, probably more like .001 (or less -- I've had to give multiple minutes of exposure to unfiltered sunlight without a lens involved at all).

removed account4 · Feb 19, 2021

there are some people that do it, but it might not be with that specific product
http://www.dianaludwig.com/photo/cyano.html
http://www.alternativephotography.com/making-cyanotypes-in-camera/

awty · Feb 19, 2021

You could pick up a small old 1/4 plate type camera for not much. Lot easy to load and the old lenses are usually uncoated.
There's also a lot of other interesting uses for plate cameras.
I haven't made a sunprint, but have done other incamera positives and negatives and stuff.

fabulousrice · Feb 19, 2021

awty said:
You could pick up a small old 1/4 plate type camera for not much. Lot easy to load and the old lenses are usually uncoated.
There's also a lot of other interesting uses for plate cameras.
I haven't made a sunprint, but have done other incamera positives and negatives and stuff.

What are you calling a "old 1/4 plate type camera"? I'm not familiar with the term

fgorga · Feb 19, 2021

fabulousrice said:
Has anyone had successful results using a sunprint paper such as this in a camera?
I tried a few times and failed. From what I gather you have to use a camera whose lens isn't UV coated. So either one of my Holgas that I would have to somehow block the shutter or one of the very old cameras I have whose glass might not have been coated during production.
Curious if anyone's tried and succeeded...

I see two issues...

1. The speed of commercial cyanotype paper is very low, it is certainly sensitized with the traditional cyanotype sensitizer or some variation of that. I suspect that they may have a formula optimized for stability when coated on paper and not for speed. These two factors are likely inversely correlated. However, i don't really know and certainly don't have a clue as to the details.

2. With regard to lenses, it is not just the coatings, but the glass itself that is a problem. Glass begins to absorb light at around 350-400 nm (depending on the type of glass) and by the time you get down to 300 nm, the transmission of light is close to zero. I don't think that we know the exact wavelength of light needed to expose cyanotypes, but it is certainly in this region of the spectrum. The key to success, would be to use a simple single element lens and certainly not a complex multi-element one. The less glass in the optical path the more UV it will pass. This is the approach taken by both of the folks whose work jnantz linked to in his/her response.

awty · Feb 20, 2021

fabulousrice said:
What are you calling a "old 1/4 plate type camera"? I'm not familiar with the term

Back in the olden days, when most of the members here were still young they used glass plate negatives instead of film. There were many sizes, 1/4 plate was 3 1/4" x 4 1/4.
They often come with film adaptors that will accommodate film or paper. You can loadvup as many holders as you have for multiple shots.
You could use any size in this style, quarter plates or similar sizes are usually cheap.....but maybe not any more.
You could also use a kodak box brownie camera type, but you can only do one at a time.

This is a folding pocket 1/4 plate camera

awty · Feb 20, 2021

Or you can convert an old Polaroid 100-400 series land camera, to do just about any size up to 4 x 5. They go for around $20.
Or you could just make a camera out of a light proof box and put a lens up one end and what ever photosensitive paper you want to use up the other end......personally I think bigger is better and my box camera takes 14 x 17 film. Then I use x ray film which is around 100 iso and after I develop the film under a red safety light (x ray film isnt sensitive to red) then I paint some cyanotype or Vandyke Brown photosensitive emulation onto a piece of art paper, dry it with a hair dryer, put the paper emulsion side up on a board, put the negative on top, then a sheet of glass ontop of that, clamp it down and stick it the sun for a bit, then process the paper, allow to dry and wallah! you get a picture to hang on the wall...

grahamp · Feb 20, 2021

That particular paper takes several minutes to contact print in good California sunshine. And that is using a perspex cover, not glass. Details at http://grahamp.dotinthelandscape.org/cyanotype.html

I have never been tempted to try a camera, but if I did I'd look for the largest format I could find with a plastic lens and a good B or T option. Remember that the reflected UV from a general scene is likely a lot lower than the UV for a contact print facing the UV source.

[Disclaimer: The Sunprint material linked in the OP originates from the Lawrence Hall of Science at the University of California, Berkeley. I used to work there.]

Vaughn · Feb 20, 2021

Too slow for in-camera use for practical applications...but why be practical?

If you are interested in going further exploring in-camera cyanotypes, look up the Cyanotype Rex process. Re-invented by the Late Terry King of the Royal Photographic Society. Just one of the chemical components is coated onto the paper, then after exposure, developed in the other.

pentaxuser · Feb 20, 2021

I haven't the foggiest notion of how to make them but as we are now hybrid here, aren't large digital transparencies from a scanner the way to go if cyanotype contact prints are desired. As far South as LA you must have a great UV source that is available for nearly all of the year

pentaxuser

Vaughn · Feb 20, 2021

Aye, but we are talking making cyanotype negatives here.

awty · Feb 20, 2021

Wonder how Vandyke brown emulsion would go as a negative. Usually a few stops faster than Cyanotype.

Always had it in mind to make Albumen negatives and then positives.....like a good puritan .

pentaxuser said:
I haven't the foggiest notion of how to make them but as we are now hybrid here, aren't large digital transparencies from a scanner the way to go if cyanotype contact prints are desired. As far South as LA you must have a great UV source that is available for nearly all of the year

pentaxuser

Heretic !

pentaxuser · Feb 20, 2021

Vaughn said:
Aye, but we are talking making cyanotype negatives here.

You are right I guess I was homing in on the best way to use Cyanotype for the best result rather than what the OP was asking for. Best of luck to the OP who appears to have chosen a very difficult route, namely Cyanotype negatives.

pentaxuser

Vaughn · Feb 20, 2021

Might find this interesting -- some leads for further research.

https://slykasstuff.tumblr.com/post/155772150296/comparing-different-cyanotype-techniques

He is doing 15 minute exposures thru an enlarger.

NedL · Feb 20, 2021

Vaughn said:
Might find this interesting -- some leads for further research.

https://slykasstuff.tumblr.com/post/155772150296/comparing-different-cyanotype-techniques

He is doing 15 minute exposures thru an enlarger.

There's also an 8 hour in-camera cyanotype negative on that page!

Vaughn · Feb 21, 2021

Missed that.

pentaxuser · Feb 21, 2021

Vaughn said:
Might find this interesting -- some leads for further research.

https://slykasstuff.tumblr.com/post/155772150296/comparing-different-cyanotype-techniques

He is doing 15 minute exposures thru an enlarger.

Was this a special enlarger in the sense of bit of a normal enlarger but constructed to do what he needs to do or could you do it with a normal diffusion enlarger and a 35mm negative focused on his "special formula paper?

He would appear to have found a method of exposure that has no need of UV light in that he uses a 100W LED?

I admit that without a full explanation of how it all worked and only a few pictures of his enlarger I became confused

Thanks

Vaughn · Feb 21, 2021

I would assume the 100W LED puts out a lot of UV and high end blue light. Looks like he is having fun.

pentaxuser · Feb 21, 2021

Vaughn said:
I would assume the 100W LED puts out a lot of UV and high end blue light. Looks like he is having fun.

Thanks I am unsure if a 100W LED means it gives out a 100W light but generates about 13W of heat as do LED bulbs of about 13W or generates the same heat as a 100W tungsten bulb? It seem to me that if it is about 13 W of heat then the use of an old condenser enlarger into which a LED bulb was substituted might work and might even avoid the need for any heat dissipation even over 15 mins a 100W LED bulb will not cut it and what is needed is the kind of square bank of LEDs that he seems to have?

However I have no idea if this is me thinking ridiculously simplistically. The great thing about an enlarger is that it gets over the usual alternative process need for making a contact negative that is the same size as the print

pentaxuser

fabulousrice · Feb 26, 2021

Wait but how about putting the sunprint paper in these old Kodak cameras that look like a box, sometimes don't even have much of a lens, and usually have a T pose?
Brownie Number 0 or number 2 - wouldn't that work?

removed account4 · Feb 28, 2021

those cameras have a meniscus lens that are choked down to about f9 or f10.
you could remove the aperture but then depending on your lens
you might have something like a Flipped Hawkeye. ..
if you are using the store bought paper you might figure out
if there is a kitchen sink chemical ( like vinegar or Vit c or lemon juice or ... ?)
that you can dilute and brush on your paper (maybe use it wet maybe dry maybe damp )
to hyper its sensitivity before you put it in your camera
I'm thinking of the legends of how astro-photographers hyper their film in hydrogen peroxide fumes to make their iso400 tri x pan like iso 200,000,000,000 *
*exaggeration

removedacct1 · Feb 28, 2021

When I was at OCAD in the mid-8os, I did experiments with cyanotype paper in various box cameras, and it took 1-3 weeks to record enough to make a usable exposure.

NedL · Feb 28, 2021

I think John's idea of exposing it wet an extremely good one and it could bring the needed exposure down into "few hours" range, or even less than that!

For a completely different process, I tried making in-camera exposures of just the FAC mixed w/ a just a little gelatin ( and possibly a touch of CA to get the pH down to where FAC is most light-sensitive, I can't remember now ). I remember the weather was warm, it was probably Summer, and I tried exposures of around 6 to 8 hours in a 5x7 camera in full sun with an un-coated lens at F-2ish. After a few tries I gave up and decided to order some FAO to mix in ( Sandy King found a mixture of FAC and FAO to be a little faster in his "backward exposed" ferric gelatin prints ). Never got back to it, but I remember thinking the exposures were taking so long that I was running into trouble with the air oxidizing the ferrous back to ferric, so I was fighting a losing battle. I have no idea if this would happen with cyanotype ( reverting to ferric ) but it sounds like it's less of a problem since people have managed to make multi-hour/day exposures.

Either way, it might help to place the damp cyanotype paper between two thin sheets of glass in order to keep it damp and exclude oxygen. I've definitely seen with my own eyes that if you put something wet onto cyanotype paper, or if there are areas that are still slightly damp from coating, the exposure is very fast.

And, thank you very much for posting this. The FAO is here and I never continued the experiments... and that would make a great project for this summer. Also now you've got me thinking.... once the gelatin dries, it becomes insoluble, so it might be possible to speed up the process I was working on by dampening the paper underneath it and exposing between two sheets of glass... that's actually a fantastic idea. ( my goal was an in-camera positive process not using dichromate.. I was able to make positive contact prints in full sun with it, but it was too slow for in-camera )

removed account4 · Feb 28, 2021

NedL said:
I think John's idea of exposing it wet an extremely good one and it could bring the needed exposure down into "few hours" range, or even less than that!

I must be channeling in my inner Ron Mowery because I was thinking about how he would say the ISO and characteristics of silver gelatin emulsion changed depending on if it was exposed wet or dry. I hope the pre-coated paper the OP is using can be manipulated theirs obviously has a preservative so it has a shelf-life. I wonder how the preservatives might impact further manipulation ( dampening, steaming, warming, coating with other benign cabinet found products &c ) to boost its sensitivity contrast &c Couldn't find a MSDS on their website..

Using sunprint paper in a camera?

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