Sunday, April 19, 2015

Blogging for Sol: Raining on the Panda Parade

Odd Bleaching, Reason Unknown
Hello, Spiders! This week has been pretty terrible as far as weather goes. Even my students have been complaining, because the weather makes it harder for them to do extra credit assignments. I give them the opportunity to do alternative process (cyanotype, lumen, anthotype or scanogram) prints for extra credit... and they all wait until the last week to do them. Of course.

So, I haven't been doing much printing lately. Nor have I made much progress on the grant project recently. I have begun to epoxy the printed parchments onto the wood, though. The first test finished curing tonight and it shows no ill-effects on either side. There's strong adhesion and everything appears to be going well. Recent grant-related developments also include 3 failures which I'll have to re-print. That's going to be challenging, since most of the last shipment of parchment was small pieces. I do have a large sheet I can cut from, but the surface isn't what I'd like... so I'm ordering another set of parchments and hoping I get some bigger bits. I'm going to include a note asking for no sheep scraps.

What I did get done was some catch-up on my documentation. I've been doing a lot of experiments with the different types of parchment and prepping for the grant work. So I had a double handful of parchment prints waiting for scans. I finally got that done! In case you were wondering, Spiders, I do not like Sheep Parchment.

In a related note, the odd fading that I've discovered lately (Mexican Heather 8, Peppervine 5) is finally scanned. I'm going to be seeing if anyone, like Christopher James or Mike Ware, can explain what's causing this reaction.

Friday, April 10, 2015

Blogging for Freya: The Difference in Splitting

Two-Stage Cyanotype, First Test.
I missed my deadline, Spiders, but I almost had a good reason. I was engaging in a new experiment today and it wasn't finished until I got home from game night. Of course, I could have done the experiment earlier in the day... but I hardly ever get work done before 2 PM. Oh well! Next week, Thor! For sure!

Apparently it is possible to print cyanotypes in a very different way than the traditional method. In traditional cyanotypes, there are two active chemicals. Ferric Ammonium Citrate (A) and Potassium Ferricyanide (B). Generally, Parts A and B are added together in equal measure to create a working solution. The working solution is then painted onto the substrate, allowed to dry fully, exposed and developed in water.

According to Mike Ware and a photographer named Jorj Bauer, it is possible to split A and B apart. The process then becomes an application of Ferric Ammonium Citrate to your substrate, dry for 30 minutes (far less time than required normally), expose, then develop by brushing on the Potassium Ferricyanide. Afterwards only a short water bath, instead of an extended wash, is required to clean off excess chemistry. All the development occurs with the Potassium Ferricyanide being added.

The advantage here is that you don't need to mix up working solution, which goes bad fairly quickly. You can keep your coated paper longer, and coat large projects more easily and without waste. Also, because the Potassium Ferricyanide partially inhibits UV light, waiting to add it until after the exposure dramatically increases the sensitivity of the print. A 200-300% increase in sensitivity is possible, at least theoretically. This drastically reduces the time required for exposures, and the depth of the shadows. Again...in theory.

I tried to use this technique today with a photogram on parchment and had... well, it's right up there, Spiders. It isn't a great success. Now, yeah... I took a shortcut and used a hairdryer to accelerate the drying of the Ferric Ammonium Citrate-coated parchment. However, I think the problem lays with how damn thirsty the parchment is. Because it absorbs and holds onto liquids with such tenacity, the Ferric Ammonium Citrate (absorbed fully into the parchment) does not easily interact with the Potassium Ferricyanide (only on the surface). Possibly a bath in the Potassium Ferricyanide might work as a developer... maybe. But that causes problems because even with only two or three minutes of contact, the Potassium Ferricyanide has left yellow stains on the image that did not wash out at all in the water. I'm afraid of trying an acid wash (generally recommended to clear highlights of cyanotypes) because that's un-mixed Potassium Ferricyanide. When combined with acids, Potassium Ferricyanide can produce cyanide gas. Not something I want to mess with.

So, maybe this works really well on paper? I'm certainly going to do some more testing... but I'm thinking it isn't going to be a great technique for me and my parchment prints. Bone, maybe? I hope so. It might solve some of my issues with the bone images self-developing while they try to dry. I'll have to do a test once I get some bone "scraps" I can fiddle with.

For the weekend and next week, dear Spiders, I have other things to play with. Aside from making further progress on my grant project, I've also got to work on a good way to clear the highlights of my parchment prints. I have some citric acid crystals that I'm going to whip up into an acid bath and see if I can get the highlights to clear. Acid helps iron salts dissolve, and that may get the yellow out of the parchment. Since those prints are done traditionally, the cyanide is not going to be released and the clearing bath should be safe. Supposed oxalic acid works really well, but I've been looking around and gotten some good feedback about citric acid. Oxalic acid is fairly unpleasant stuff by my standards, so I'd prefer to avoid it.

Thursday, April 2, 2015

Blogging for Thor: Wooden Wonders

Newest of my Osage Orange mounts
Tomorrow I'm expecting a new shipment of wood from Kansas! The same eBay seller whose been providing me with osage orange, as discussed recently, was able to find a branch large enough to cut me 30 slices between 4x5 and 5x5 inches, all the slices just under an inch thick. These 30 pieces, shipping included, cost me $4.67 each.

Isn't it great that the best way to present my work for the CSA Grant Program was also the cheapest way? That almost never happens, Spiders! I just need to get the wood, cut parchment to the proper size and shape for each one, print an image on each of the 30 pieces and then epoxy the prints into place once they've dried. It should take about a week total, maybe two depending on weather.

The jewelry half of my CSA project is also going well. I've got a bunch of parchment sized and ready to coat (which I'll be doing tonight), then it can be exposed. Since the jewelry parchments are tiny, I can expose a lot of them at once and dry a lot of them at once. I'm hoping to get at least 10 of the jewelry parchments printed and drying this weekend, actually.

Considering the lovely appearance of the last two wood-mounted prints, I'm looking forward to seeing thirty of them all spread out. Should be pretty impressive!!