Archive for the ‘alt-photo’ Category


More gum dichromate

June 21, 2008

I’ve read in more than one place that gum printing is both the simplest printing method to use and the most difficult to master. I would agree with both assessments. Pretty simple ingredients to start with but it can be very challenging to get a working image. I’m at single color, single pass printing and trying to get a handle on exposure and pigment mixing.  And I will likely be here for a while.

To that end I’ve got another batch of prints to play with. This time I’m using a bit nicer paper, some Weston Diploma Parchment. Pretty good stuff and I can tear down the sheets into four pieces each large enough for a 4×5 negative. Makes a good practice size.

Lessons learned :

1) It is easier to apply the gum and dichromate with a foam brush but a foam brush will raise the grain of the paper. Doesn’t matter how light the touch, it just seem to happen with the WPD.

2) Hake brushes shed hair. Cheap brush, expensive brush, they both shed. The good Joto brush less so but it still means watching for hairs stuck in the gum.

3) It doesn’t seem to take much UV at all to start the gum hardening. Prep’d a few sheets about 11am this morning and I thought it was dim enough in the basement to work out of the dark room. Seems not so. Had a dickens of a time getting those to clear, even rubbing the wet print it wouldn’t release the pigment. However sheets prep’d in the darkroom with just the red safelight (need to get a 40W yellow bug bulb) did much better.

4) Gum prints much faster than I expected. Got reasonable exposure in 2 minutes of noon day sun. Didn’t worry about the contrast issue, just used direct sun. It did produce a bit of a contrasty print. And I am seeing just a little bit of a POP image in the print as I remove it from the contact printing frame. During the first session I did not see any fugitive image.

5) Sizing the WPD with gesso works better than unsized paper. Pigment sinks too deep it seems and doesn’t like to release. I need to size some paper with gelatin and glyoxol and experiment with that too.

6) Clearing the print is taking quite a long time. Could be pigment choice, could be gum has hardened too much, could be water pH, could be unsized or not the right sizing of the paper… Lots and lots of variables here. Slowly getting a handle on them one at a time.

Here is a shot at un-sized paper and the hake brush. Much better paper finish (not “fuzzy”) but really didn’t like to clear at all so the print is a bit muddy and low contrast. 1:1 gum and potassium dichromate with lamp black as the watercolor paint. This sheet was also coated outside the darkroom in what I thought was low light but must be just a little too much sun coming in even at 11am and on the west side of the basement.

Wabunsee County School House

Also I wonder if maybe I shouldn’t add a little bit more pigment.

Next is a bit better result with gesso sized paper and using a foam brush. The scan doesn’t show the paper surface but it is a bit on the fuzzy side. Same 1:1 gum and potassium dichromate. Also this time

Pillsbury Crossing Tree

More pigment this time (maybe 1 1/4″ worm this time instead of 1″ or a bit less the first time).

So key things to walk away with are:

You can’t coat the paper in too dim of a light.

Clearing the images takes a lot of patience.

Foam brushes are easy to use but with the WPD paper I don’t like the finished look.


Gum dichromate – watcha’ know, it worked!

June 14, 2008

OK, so the long term goal has been to get more comfortable using my 4×5 and 8×10 cameras to make LF negatives suitable for alternative process printing. To that end, the first half of this year has been learning how to work with my 8×10 and Pyrocat-HD as a developer. So far, so good.

On the alt-process front, I started with cyanotype because it is cheap and quite forgiving. I’ve also played with salt-printing. More of that to come now that I have a better handle on the negative making process. And I’ve started work on improvements to the darkroom to make things a little easier. Working in a converted bathroom can be a bit challenging sometimes.

But for some time now I’ve been reading up on gum dichromate (sometimes called bichromate, usually in the older literature but the accepted modern chemical name is dichromate so I’ll try to stick with that). I’ve been lurking on the alt-process list and reading just about everything I can get my hands on. First let me thank the gum printing regulars over at the alt-list. Always a good read and so far every question I’ve had pre-printing session I’ve found an answer in the list archives.

Second let me also say “damn you all” to the same people for making this sound so appealing. Argh! There goes my last 7 1/2 minutes of free time! Oh well. 🙂

So, while waiting for my single color kit to arrive from Photographer’s Formulary ( by the way) I decided to look in my current supply of chemistry. Why get the kit by the way when it is pretty easy to get all the chemicals individually? Well, after a quick check on cost, turns out the single color kit is pretty economical. But back to my chemistry supply, turns out I have a 1g packet of potassium dichromate that I had bought thinking I might use a weak solution for contrast control in cyanotype and salt-printing.

Math time! For gum dichromate you need a dichromate, usually aluminum or potassium. In both cases, you usually use (but not always) a saturated solution. For potassium dichromate, that is about 13% at room temperature. So, I have 1 gram of chemical, how much water to make a saturated solution? 0.13 = 1 / x and so x = 8ml. OK, I rounded things a bit but close enough. 8ml of solution is more than enough to make several 4×5 prints and play around.

Next problem is paper sizing. Three simple solutions to this. First, don’t bother, just use the factory sizing. OK for single coat, may be a problem for multiple coating. I’ve been warned! Second, use gelatin. A single coat gum can probably get away with unhardened gelatin sizing but the use of a hardening agent would be better. I don’t have any formaldehyde, formalin or glyoxal. However the PF kit comes with glyoxal so I’ll try that later. And finally, doing a lot of reading I’ve come across the suggestion to use gesso diluted 1+3 or 1+4. Gesso is cheap and easy to find. Hobby Lobby even happens to have a 50% sale on art supplies right now. So gesso it is for a first look at sizing.

Gum arabic is the colloid for this “emulsion”. So I’ll need a little of that. And of course that too is 50% off at Hobby Lobby so I picked up a small bottle of the Windsor & Newton branded stuff.

Two more issues, pigment and paper. Everybody says to use high quality pigment. Easy, again Hobby Lobby is including the Windsor & Newton pigments in he 50% off sale. Small tube of Davey’s Grey. I think the PF kit comes with lamp black. Another reason for choosing Davey’s Grey is some anecdotal evidence I found that it clears quickly. Good choice for experimenting!

Last is paper. I have some nice Weston Diploma Parchment but I want to save that until I have a better grip on technique. In the past with cyanotype and salt prints I’ve had good luck with some of the $4 generic pads from Hobby Lobby. So once again I’ll just try that.

Oh, and a couple of new foam brushes and some vinyl gloves for mixing. Already have those.

1) Pre-shrink the paper. Discussion on the alt-list about this and strong argument made to not bothering with the hot water + 1 hour method. Just soak the paper for a while. It can start as hot water but just soak and shuffle. So I soak and shuffle. Then hang to dry.

2) Mix up potassium dichromate solution. Done! Store in glass bottle. I have lots of little ones with dropper-stoppers. Done!

3) Size some paper. OK, since I’ve only got one color to play with and for a first test I was going to do a single coat print, I can size a few sheets of un-shrunk paper while the other stuff dries. Gesso mixed 1+3 with distilled water. Soupy stuff! Paint on evenly with clean foam brush and dry. Done.

4) Did I mention I was just wanting to experiment? So that means pull out a sheet of paper, and just coat it. No shrink, no size. Just 1:1 gum and dichromate. Then into a little plastic shot glass I place about 1″ worm of Davey’s Grey and mix in the gum and dichromate.

5) Coat paper. Another clean sponge brush. Just like the literature says, coat evenly, quickly and don’t worry too much as it tends to even out a bit as it dries. Yes, it does even out a bit as it dried but it was still splotchy. Cheap paper + unpolished technique = splotchy coating, remember that.

I let the coated paper dry for a while and then made the sandwich in the printing frame and exposed for about 15 minutes over the UV blubs. Unlike cyanotype and salt-printing you don’t get a POP image to judge, at least I didn’t with the Davey’s Grey mix. Just flying blind here but the time felt right.

Float the paper in clean water face up for a minute or so. Som’ bitch I see the image starting to form up as pigment floats off. Carefully move the print to a second tray of clean water and let it soak face down. I would check it about every 5 minutes over the course of an hour. Also during that time I coated two more sheets, one sized but unshrunk and a third shrunk but unsized. And based on what I was seeing after about 30 mintues of developing in the first print, backed off the exposure to about 6 minutes. Probably too little exposure (guilty of changing multiple variables).

All in all, a long evening but very productive! This is great! Start a new section in the lab notebook and start recording results so I can get some predictable results!

After all this rambling, here is a scan from my first sheet. I cropped it a bit and a slight adjustment post scan so that it matched on my monitor. As always, YMMV! Maybe a bit over developed as you can see how pigment has floated away from medium high tones, exposing brush strokes. Oh well, what is most important to me is that it WORKED! Ha!

Anchor Pully

No silver was harmed in the making of this print… 😉


Finally saw it happen with Pyrogallic acid developer!

June 3, 2008

My photo technique goal for 2008 has been two part. First part was to get more comfortable with my 8×10 camera. The second is to learn to use Pyrocat-HD as a developer. Combined, these two goals are so I can get back to alt-process printing with Cyanotype, Salt Printing and Albumen. One thing I read about Pyro based developers but had yet to see was the “bas relief” effect in the negative. As the gelatin tans, the legend says, you can see the image in a faint bas relief from the emulsion side. Finally saw that happen with on of my 8x10s. While not the greatest negative ever made, I finally saw the effect. Neato! The negatives were made out at the Baker Wetlands, just to the south of Lawrence, KS. Mostly I was out for the exercise. Physical exercise ’cause I need it. And the mental exercise of working with the 8×10. Setting up, learning to see how the 14″ lens sees, that sort of thing.


Proof prints:

   Footpath Looking East  Birdhouse

ERA 100 @ 80, Pyrocat-HD, 2:2:100 8min, Jobo CPP2

Printed on Ilford MGIV WT (old stock), selenium 1+3, 5 minutes

Nothing spectacular about either composition but the birdhouse negative is the first one where I actually saw the bas relief effect. 



Is Polaroid still dead? Yep. But it does nice work for a dead medium!

May 11, 2008

Finally got some time outside with the 8×10 and Polaroid 809. I think I have my three 8×10’s ready for the APUG Ode To Polaroid print exchange. Next up is to mount them and prep for shipping.

Singing Sunflower

Student sculpture at The University of Kansas, Murphy Hall courtyard


Polaroid is Dead. Long live Polaroid.

April 5, 2008

Finally, a reasonably decent day with enough sunshine to go try my Polaroid 809.  What is Polaroid 809 you ask?  It is 8×10 color instant film.  Requires a special holder and processor to pull the negative, positive receptor sheet and chemical pod through the rollers.  I have on loan from Alex Hawley a holder and tabletop processor.  Thanks Alex.

Loaded up the Seneca Improved View 8×10, installed the Leclair 13″ brass lens and with the judicious use of rubber bands and a Lee filter holder I can put the Packard shutter on the front of the lens.  With the camera racked out to about 20″ and some quick calculations, 1/3 second exposure is called for.  Except I can’t really guarantee anything that quick with the Packard.  Mine doesn’t have the “instantaneous” mode so best I can hope for is something under 1/2 second.

Not bad, a bit over exposed but what the hell, it worked!  Only screwed up twice getting to this point.  27 more sheets to go!

Three Amigos


A bottle of snot!

March 30, 2008

Saturday I acquired a bottle of snot.  OK, not really a bottle of snot but that is what a bottle of Liquid Light emulsion reminds me of as I melt it out and divide it into smaller containers.  I went to the local camera store to have some color enlargements made and noticed they had a bottle in their little display fridge.  Turns out it was expired so they discounted it by 50% and Becky bought me the bottle for my birthday present.

I’ve melted out about 1/2 to 2/3 of the bottle into a collection of black 35mm film cans.  I then took one of the cans and diluted it about 2 parts snot to 1 part photoflo (working strength).  This I kept on the hot plate and melted down further while I coated several sheets of watercolor paper.  After a little bit more drying time I’ll slip the paper into some black bags so I can play with it tomorrow.

This should be very cool.  Some of the sheets coated nicely, at least it looks nice under the safelight.  A few of them I think the gelatin started to set while I was brushing and so they may have some emulsion balls stuck to the surface.  Almost like trying to spread out rubber cement.


Fuji Transfers

March 29, 2008

Not the greatest day outside today. I had hoped for some sunshine because I wanted to get a jump on some 8×10 Polaroid work for the Ode to Polaroid exchange at APUG. But no such luck.  So instead I decided to take another stab at using Fuji FP100C for emulsion transfers.

I don’t have a Daylab or 405 back so I make the images in-camera.  This time I decided to use FrankenRoid which is a pinhole MP4.  Get out the rubber duckies and barrel of monkeys, turn on the Wagner and create!


6 minute exposure with heavy overcast.  20 seconds development, then peel and place on the Arches Aquarelle (hot press).  Roll for 1 minute, single direction, with a hard brayer.  Important that the peel and place be done in the dark or with a dim safe light.  Once down, the back of the Fuji is light proof so the lights could be turned on, I just worked under the safe light the whole time.

Fuji FP100C has a very pronounced blue shift for long exposures so I was to use a Daylab I might want to adjust the color pack to be a little minus blue.  There are some good discussions of this technique on and  .   Both sites have search functions so key words like “emulsion+FP100” or “fuji+transfer” should help find them.  I just feel lazy right now and so don’t have links to include in this entry.