From the “Big Collodion Test” I did a while back the Old Workhorse Fast Clear stood out to me as it gave me a much shorter exposure time. Having used it a bit more, including for negatives, I have come across something I don’t like, namely striations. Firstly I’ll repost the formula again so we all know what I’m talking about exactly:
240 ml USP Collodion
200 ml Alcohol
200 ml Ether
1,6 gr Cadmium Bromide
1,4 gr Ammonium Bromide
5,0 gr Ammonium Iodide
When making positives the plates did not suffer from striations. When making negatives however this was extremely apparent. After having talked some more with Mark Osterman it came to my understanding that the Ammonium Iodide was the culprit here. On ambrotypes made on black glass with lots of contrast they’re less prone to show but on clear glass with an unbroken gradient of tonality they will be very apparent.
It’s also the chemical compound that gives this formula the “fast clear”. Now, personally I don’t care whether a solution is fast clear or not, usually when I make a fresh batch I don’t intend to use it straight away.
Cutting back on the Ammonium Iodide or substitute it with Potassium Iodide would solve this matter and (hopefully) retain the speed I’m after. The next batch will be the same formula as mentioned above but instead of Ammonium Iodide using Potassium Iodide, the original Old Workhorse formula that is. Will report back!
So..here we go! Yesterday I’ve shot 12 plates (2 plates were to determine exposure time) of 5 different collodion formulas and 2 developer formulas. Please keep in mind this test is performed under my specific conditions, with my chemistry, age of silver bath etc etc so all conclusions that I draw here may not be consistent with your findings or may not turn out the same when you give them a go.
Having learned that a formula is just a formula and has to be adjusted according to specific circumstances (temp, humidity, age of silver bath, amount of alcohol used etc etc) this is by no means a ‘scientific’ test or whatsoever, merely meant for me to see how a 2 salted collodion will compare to a 4 salted collodion, if I would gain anything in speed from one of the formulas and how the tonal range would vary. Anyway, enough of this diplomatic stuff 😉
The difference in developer is not really that interesting, the difference you might see may just as well be caused by flowing too much developer over the plate, wiping off some of that precious silver thus changing the result. I used the Osterman developer and the Lea’s Sugar developer (for the exact formulas see this former post). The latter because of the amount of restrainer used (sugar) might be interesting to use in hot conditions so I’ll surely be bringing it out when summer hits our land to see how it fares. I’ll post all of the photos anyway, if you’d like to have them mailed to you to give them a closer look, shoot me an email and I’ll send them to you.
Above the test setup I used to make the photos. A lot of different colors to see how they would come out on the plates. A color chart and a grey scale to check out tonal range and dynamic range. Orange carrots and orange mandarins, oh how different they look on the plates!
Specific Circumstances of the Test:
Silver bath – Specific Gravity: 1,06
Silver bath – Acidity: 4,5 -5
Silver bath – Age: +- 2,5 years old
Temperature: 17,6 degrees
Fixer: Sodium Thiosulfate 30% (I can’t stand the smell of KCN so never use this indoors at home)
Lighting: 2 Falcon Eyes 928 lights in an approx. angle of 45 degrees on the subject, 1 on each side.
Medium: 4×5″ Black Glass Ambrotypes
Lens: Steinheil 230mm
All the plates are unvarnished as I didn’t want to run the risk of screwing up plates 😉
I don’t have much to say about No.1 +2. This is the formula I’ve used exclusively until now.
No. 3+4 are the etherless versions and the first thing that I noticed was that with both plates I have an inconsistency in the background at about the same locations. They are the only two plates that have this. On the scan it is not that apparent but on the plates it is.
The plates that really stood out to me are No. 7b+8. No. 7 + 7a were over exposed as you can imagine. 7b is still on the light side so it saves me over HALF the exposure time, at least one stop that is. For studio use this will definitely be the one I’ll be working with. For outside use it’s probably a bit too fast, or I’ll have to stop down the lens of course but I might give Lea’s Traditional Landscape a go and the OWH.
The plates that surprised me the most are No. 9+10. This particular formula didn’t clear at all. Lot’s of undissolved salts at the bottom of the bottle which I decanted before using. I also filtered this collodion version before use but didn’t make much of a difference in the clearing part. I didn’t expect anything from it when using so I was surprised something came up on the plate. I should’ve dissolved the salts first in water before mixing with the alcohol and ether (stupid me) but it worked nonetheless.
Another thing that’s odd on plate 9+10 is that the SUN bottle on 9 is much lighter than on 10. Seeing that this is the only thing coming out much lighter it’s probably a flaw in my development, having poured off some of the silver with the developer. This is however my best guess as to what has happened there. I don’t recall the exact development, curiosities etc anymore from these plates.
For people not eager to work with Cadmium Bromide this is a proper way to go I guess. It’s a contrasty plate, pretty even all over and compared to the other formulas (except the OWH) comparable in speed. It also gave the most detail in the SUN bottle of all the other plates, together with 1 +2.
The plates developed with the Osterman formula seem the most consistent which gives cleaner more even plates (except with the Lea’s traditional formula, sugar is also fine). It’s a developer I’ll take as a starting point from now on and learn how to adjust it when needed.
Well, there you have it. I hope you enjoyed this overview, I sure did! Doing the testing was a good thing to do for me. I now have a good place to start from and I’m really happy to have found a formula which gives me shorter exposure times with good tonality.
Maybe I’ve forgotten things which I may add or adjust in the future. Thanks for looking and have a great weekend!
– 🙂 –
Today I found the time to do some testing. My “fresh” batch of collodion causes stripes on the plates, not all of them all as “bad” as the other, that’s what made it a bit awkward. But time to figure out what was causing it. At first I though it was the non- room temperature (I used collodion straight from the fridge, then I thought adding a little alcohol would do the trick and it did help in the beginning but the stripes returned again. Yesterday I added some ether / alcohol mix I still had in my fridge to my pouring batch and kept it at room temperature so today I would have the good stuff to work with.
Another thing I noticed from the last shoot was that I poured 7 plates from my pouring bottle and it was empty. Wayyyy too fast, indicating the collodion was too thick, suggesting too little ether / alcohol. The batch poured / flowed much better today and the stripes were, except from a few minor ones, gone! I even tried a negative 8×10″ of clear glass I cut recently. The latter also being very interesting to show at the workshop and demos I am about to give.
Mixed some fresh fixer and continued with the filtering of the varnish, that last bit taking up quite a bit of time; goes very slowly. Once done I’ll have some great stuff to be working with though, particularly smelling very nice!
Have a good day!!
Yesterday I had someone coming over for a wet plate collodion demo and that forced me to test my two batches of Collodion, old and new, with the lighting setup from FalconEyes I bought not too long ago. With my old collodion (approx. 1 year old) I couldn’t get an image to form on the plate with 1 minute of exposure. I bought the lights to shorten my exposure time. With the new batch I had an image within 30 seconds. Still have to try it with human skin to see if it’s even shorter (I used a glass head this time) but didn’t have the time yesterday.
The girl came over and I used her for some plates which I made outside because the weather was terrific. With the new batch I had a lot of stripes and stains. When trying the old batch the stains were gone but had trouble pinpointing the exposure as it’s a lot less light sensitive than the new one. The stripes could be caused because the batch came fresh out of the fridge and hadn’t had much time to reach room temperature. I’ll have to look into that because I will need it to work soon (demo SASK St. Niklaas). You can see the stripes in the 4×10″ plate but I like it anyway. Since it’s my first 4×10″ I’m going to keep it!
I look forward to the series I’ll start making of Maastricht soon on this size. It’s a fun size to work with and to look at. These series will moreover be awesome in 10 to 20 years from now as Maastricht is changing so rapidly.
Have a great day y’all!
P.s. my “new” camera works like a charm 🙂