Well, so far not so good. First we tried using a light meter set at 0.5 ASA and doing exposure stripes of just a black, a grey and a white cards with 1, 2, 4, etc... flashes. The resulting very weak and low contrast plate vaguely showed the three cards, but strangely no exposure increment stripes... I can't fathom why.
Having just barely finished my silver nitrate tank and plate holder for this first test, I didn't have a holder to dip the plate and take it out of the tank, so I grabbed a thin brass rod and bent it to make a makeshift holder. That was a double mistake. The acrylic plate floated up, we had to somehow fish it out, and the brass reacted with the silver nitrate...
So I bought some 1/4"x1/4" and 1/8"x1/8"square and 1/4"x1/8"rectangular plastic rods at the model store and made a plate dipper with grooves that would prevent the 5x7 acrylic plate from floating away.
For the first test, I made a mess trying to pour collodion on the plate directly from one of the Erlenmeyer Flask that came with the kit , but still went ahead and dipped it in the silver nitrate tank, making another mess because the tank was vey full and it made the solution spill over, wasting some. I left it anyway in the silver nitrate bath for 3 minutes or so (it is not supposed to be really critical) while I mopped up the spill. That plate dipper drags out too much solution too, so I will have to make a slighter one with 1/8"x1/8" rods instead of 1/4" rods.
I used one full power flash of my strobe placed 3 feet from the subject with the lens wide open. I developed it under a red safe light until the negative image came up, washed it to stop the development, turned the lights on, bleached it in the fixer, dried it, and sprayed a coat of black lacquer on top.
I should explain that rather than putting the plates in front of a dark paper or cloth, I found I got deeper blacks and better contrast by simply spraying a coat of black lacquer over the dry collodion emulsion. That may not be archival, but will work fine for initial tests.
The plate is on the dark side, the grey scale is blurred and there are irregular lighter swirls caused by the bad collodion pour, but at least I HAD AN IMAGE!
For the second test, I cut a 5x7 piece of aluminum flashing and painted it black with lacquer. So this is technically a tintype instead of an ambrotype. I moved the camera and the strobe a little close at 2.5 feet and did one full power flash wide open. I switched hand, but the pour of collodion was still messy and wasteful. I developed about 15 to 20 seconds and ran water over it. I could not see any image, but after the fixer bath, I did get one, rather dark:
For test #3, I used a plexiglas plate. I moved the flash back to about 4 ft to try to give less exposure and slightly more time in the developer. And it did come out the best so far, lighter and with more contrast, except that the plate got badly scratched when I pulled it out of the silver nitrate tank, and my pour is still creating messy swirls(I will claim that clumsiness is because of my shriveled up left hand and a bad cut from a table saw on the thumb of the right hand) :
Since a little less exposure yielded better results, I tried the fourth test with the lens stopped down to f8, and the resulting plate ended up with almost no image.
So plate #3 was apparently the sweet spot in terms of both exposure and development, and we will have to try and define the best development time better next time.
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