Wet Plate Collodion Questions

[RobertP]

(there was a url link here which no longer exists) attachmentid=8789&stc=1&d=1192399539....Scott, this is what I use. It is a wickless dual element alcohol lamp. It came with the little short wind shield that you see in the pic. I added the stainless pipe chimney and it keeps the heat more centered. I have 4 of these that I use simultaneously for 12x20 plates. It provides a huge heating area.

 

[RobertP]

Varnish provides a protective surface regardless if it is an ambrotype or a negative. The collodion surface is very fragile. But I'm sure there are people who leave them bright. But why risk damaging it when you already have put so much work into it already. I'm not sure what atmospheric contaminants would do to the collodion surface also.

 

[Neil Miller]

Of course varnish protects both ambros and negs. But originally, ambros were matted and cased. Ray Morgenweck sums it up neatly:

"Sulfur compounds in the air eventually tarnish and darken the silver. The surface highlight areas buff down to a sheen. Gradually the whole plate looks greyer. Tintypes develop rust blooms.

If you seal the plate from the air, by using a cover glass and a mat spacer, the image will last essentially unchanged for years. Some of your best plates can be the bright and white ones, prior to varnish. So, theres no reason not to seal them and keep them that way. An 'underexposed' ambrotype on black glass, left white and bright and sealed up, has a wide tonal range and can be stunning under good lighting. I use bulldog clamps to hold it together, and Scotch 3M photographic tape (black, available through Pearl Art) to seal the edges.

Id say, if you dont want to varnish, get a good method of sealing. If you do, dont bother with other varnishes, learn to use the sandarac well."

Regards,
Neil

 

[RobertP]

There goes to show you two different schools of thought. The Morganwreck and the Coffer. Why not varnish first and then have the best of both worlds. Yes the sandarac lavender varnish is the only way to go. I have noticed at a certain angle my tintypes have a flare or metalic look that I don't find very appealing. But I find varnishing even easier than flowing the plate and it adds even more to the aesthetic. At Coffer's we would shoot all day long and then after dinner varnish plates by oil lamp way into the night. Again I guess it is just a matter of taste, but I do know some people who just can't get the hang of varnishing or hate that step for some reason.

 

[RobertP]

The old 1860"s literature goes into great detail about varnishing. So even though they may have been matted and cased they were probably varnished first. I had the pleasure of holding Gardner's plate of Lincoln and a few of Brady's plates when I toured the National Archives in College Park, Md. All were varnished and they looked gorgeous some 150 years later. These were bare plates no matting, or framing.That sold me on lavendar varnish.

 

[Neil Miller]

There's a very simple reason not to varnish - the plate was incorrectly exposed but looks pretty good as-is, whilst varnishing it would detract from its look, i.e.: kill the brights.

The old literature also mentions that tintypists and others at big events didn't have time varnish (for some odd reason - I would have thought it was quite a quick process, but maybe some sandarac formulations took too long to set - I've seen some that have impressions/marks/defects in the surface that were obviously caused by them not having been dried sufficiently before being put into purse or pocket). Rob Kendrick cites this somewhere.

Sandarac isn't the only way to go either - the CWR forum has a piece about the civil war where tintypists were gathered around the soldiers and taking pictures, it mentions their "amber beads" and chloroform - it's a varnish as old as sandarac: not as tough, but it hardens fully almost immediately. And there were others - plenty of others, using lac, dammar, copal and other gums/resins.

BTW, another thing about sandarac varnish is the fact that nowadays it is used on a warm plate, sometimes it is even warmed itself. Towler (author of the pretty definitive text "The Siver Sunbeam") quotes it as being applied cold. A cold varnish on a cold plate. Maybe the plate was only warmed in the first place to dry it? Who knows. I suppose it would have taken even longer to set-up used like that.

I guess that JC and the rest of us were not around in the latter part of the 1800s, or we wouldn't have to reinvent a process that was so well documented back then.

Regards,
Neil.

 

[schrochem]

Robert and Neil thanks for the back and forth.
There were some interesting tidbits in there.

Scott

 

[RobertP]

Neil, So what you are citing here is the only ones who didn't varnish back then were probably the ones who didn't have the time to. Yes chloroform is still used today in some varnish formulas. But a lot of people have come to the conclusion that it is a solvent and it adds no significant value when compared the the voliatility of the chemical. But some will argue otherwise. But the bottom line is if you want to do wet plate then learn to varnish. The plate is warmed, then flowed with vanrish with the pour off end dabbed to take off the excess then warmed again to set the varnish. The formulas we use now are just like the formulas used back then. It doesn't take that long unless they were shooting for a penny a pic back then and were in a hurry to produce as many plates that were equal to the people that were standing in line. So they were in a hurry. There were a lot of very small plates being produced in 1/9 plate and 1/16 ( postage stamp size) For these they may have figured, why bother. When there was a line of 20 people waiting to get their picture taken and varnishing just held things up. And at a penny a pic?

 

[RobertP]

I want to try the chloroform formula. There is a guy on the CWR site that uses it and they say his varnish is the best around. Although it is just a small amount in his formula.

 

[schrochem]

Okay, I have another question that had my curiosity from the beginning. I'm sure most of you don't do the tests and I realize it's a range, but I was wondering what the approximate ISO is for this process. I know it's slow....

 

[Neil Miller]

Robert, with big events/big workflow I guess that's just the way things were back then, but how much was a penny worth to a struggling, often itinerant photographer? 20 people = 20 pennies?!

The main exception, to my mind, would be a plate that would be ruined by varnishing it, as explained earlier. The term "in the bright" after all has entered into the vernacular - if it wasn't a commonplace thing, I'm not sure that it would have become so widely an accepted practice and one that would warrant it's own by-line.

Chloroform is indeed a small amount in the original sandarac formula, but there may have been a good reason for it. Sometimes the alcohol content of the varnish attacks the collodion. I believe this is partly the reason why some people warmed the plate - the excess alcohol in the varnish was driven off by the heat before it had any deleterious effects. George Berkhofer cautions against warming the plate to just bloodheat for this reason - others say "uncomfortably hot to hold." Perhaps that is why Kendrick uses a blowlamp? (I did try that, but cracked many plates, burnt my hand and singed all the hairs on my forearm off!) Maybe the chloroform content counteracted this - I don't know. I do know that the amber formula relies on the solvent effect of chloroform and ether to firstly dissolve the amber and secondly to evaporate quickly leaving a thin, hard amber film behind - one that could have been cased immediately. It may be just my bad luck, or bad chemicals (bearing in mind that, at worst, we are talking about people who used water from puddles and chemicals whose purity doesn't even come close to those we use today - the water content of collodion being a prime example when the ether/alcohol mix used to dissolve guncotton was highly questionable), but the sandarac formulas I have used do not fully harden with heat - they take time as well. I've had stacked plates stick to each other, and I know others have, to.

If you want to try a sandarac varnish with chloroform, Towler's 1864 masterpiece has this formula (note that it is a cold varnish):

"The following varnish is used on the cold plate, is very hard when dry, and is not softened at a high temperature when printing.

Gum sandarac, 4 ounces.
Oil of lavender, 3 ounces.
Alcohol, 28 ounces.
Chloroform, 6 drachms.

Digest, dissolve, and decant as usual."

Note that he doesn't say that it becomes hard immediately, which would have probably precluded it from events when people wanted to take the image away with them - probably!

Regards,
Neil.

 

[RobertP]

Thanks Neil, The formula I was referring to is the one Wayne Pierce uses. He got it from the " Silver Sunbeam" and it is also listed as a cold varnish but Wayne heats his plates before and after. His varnish, Szabo says, is like glass. I'm sure his formula is very similar to the one you list here if not the same one. Since it is from Towler's book.

 

[RobertP]

Here is the formula Wayne uses: 220 ml ethyl alcohol 32 gm powdered gum sandarac 28 ml oil of lavender 3 ml chloroform

 

[Ty G]

Hello Austin, TX. About approx. ISO's etc. There is no use to figure it. If you figured it with todays light, collodion mix, lens. Then tomorrow it would be different because as collodion ages, the sensitivity changes as well. My exposures just depend on what the light looks like. I do lots of Civil War reenactments, and exposure ranges from 1.5 seconds to 5 seconds.

Ty Guillory
www.tystintypes.com
Mineola, TX

 

[mark]

So, how do you figure exposure?

 

[schrochem]

Hi Ty. Nice to see someone closeby doing tintypes. Thanks for the answer on the speed, I figured as much
There is another question about time that I'd like to ask to you or the community itself. What are the time constraints involved. I haven't really found much in terms of that. It sounds like you need to wait a 'little' before putting the plate in the silver, then after that I don't know how long you have to make the exposure and get it developed. Are we talking within 10, 20, 30...mins?? What kind of anomalies do start sprouting up as the plate starts to dry?
Thanks

Scott

PS: well I'm now revested in an 8X10 and two lenses....so I'm that much closer....just don't tell my wife BUT I have an excuse. I can make a beautiful portrait of her beloved son. Yep, that's it!
I also sent off for Coffer's manual and DVD set.

 

[Ty G]

Mark,
Honestly it just becomes an very well-educated guess. You learn your lens and collodion mixture. I sometimes do a test plate before I start with customer tintypes, then go from there. Of course, exposures change somewhat throughout the day. Also, keep in mind that I hand-develop, so that gives more control with exposures.

Scott,
The question about time; collodion gels before putting into silver (@20 seconds). From the time pouring collodion to fix should be less than 10 minutes for entire process. Then of course is washing, drying, and varnishing.
J. Coffer's manual will make everything make more sense.

Ty Guillory
www.tystintypes.com
Mineola, TX

 

[schrochem]

Thanks Ty, that's pretty fast.....
Okay, I should stop with the questions until I have more hand's on experience, but I'm a curious creature
Do people 'adjust' the process in some way to affect different parts of the color spectrum? I guess what I'm saying is do be make different 'films' like modern day TMAX vs. TRI-X, etc, etc. and so on and so forth?
Scott

 

[Ty G]

Collodion is monocromatic. There really is no "spectrum." It is blue-light sensitive.

Ty Guillory
www.tystintypes.com
Mineola, TX

 

[RobertP]

(there was a url link here which no longer exists) you can hand color your tintypes. This was my first attempt at hand coloring.( Of course I was assisted by John Coffer.) The man is holding a spectrum chart this will give you an idea of how blue sensitive this process is.

 

[RobertP]

Red is rendered black. John had us shoot this to give us an idea of the sensitivity.

 

[schrochem]

Ty, I hope it's monochromatic!
Yep, that's what I was wondering about (blue sensitive). I was just curious if anyone had tried to 'shift' that at all.....
Robert thanks for the photo with the spectrum (I had seen it earlier). Because of our earlier discussion on reversed images could you tell me what the color order is....?
Gracias
Scott

 

[RobertP]

I'm somewhat confused now myself I think it is L to R red to blue

 

[smieglitz]

Bromides extend the spectral sensitivity a little towards the green, but not much. There may also be an effect using different cations, but again it would be a small effect. Collodion is mainly UV and blue-sensitive, but a pure iodide emulsion will have less spectral sensitivity than one made with a bromide and iodide mix.

It would appear that heavier cations (zinc, cadmium) give a little more spectral sensitivity than lighter ones (potassium, ammonium, sodium, lithium).

 

[RobertP]

Ok I got the loop out and read the bottom of the chart he is holding. It is a Kodak color control patches. So it isn't a blue to red spectrum. If you can find a 9 patch Kodak color control sample on line you will probably find the lighter patches the blue and violets. If you find one to compare match the patches in reverse. The one in this photo is reading right to left.