Re: Sources for wet plate collodion chemicals

In response to Richard, I wrote:

>> "Brightening" is the term used for methods that create a
>> whiter-looking silver deposit, which is desirable when the image is a
>> positive (i.e., tintype, ambrotype, and daguerrotype). As you know,
>> modern silver-gelatin materials tend to produce large "fuzzballs" of
>> silver filaments that absorb light and look black. The positive
>> silver processes depend on much smaller, reflective deposits of
>> silver that look whitish. Brightening accentuates this effect.

It occurs to me that a further point might be worth making on this thread.
The "new tintype" kits that use liquid silver-gelatin emulsion do not
produce the finely-divided, whitish-looking silver deposits that the wet
collodion processes produce. Accordingly, the best that can be hoped for
is a rather dull simulation of a real tintype. Unfortunately, there is no
good way to persuade these S-G emulsions to produce good, whitish silver
deposits.

Note that old tintypes are themselves often dull because the original,
whitish deposit of finely-divided silver has oxidized over the years and
does not appear nearly as white as it did originally. If one wants to see
the real potential of collodion, I suggest trying to find ambrotypes
mounted on black velvet produced by a current wet-plate expert, or very
well-preserved originals of the same type. It is a stunningly beautiful
process. Haunting, actually, at least to me.

Best regards,

etienne
Received on Sun Aug 28 23:08:47 2005