[alt-photo] Re: wet-plate collodion

[Bob Barnes]

great, Thanks Kerik!
Bob


On Apr 13, 2010, at 5:45 PM, Kerik wrote:

> This is not explicitly true. Collodion negatives only have a long  
> scale if
> they are intensified, which was common practice back in the day to  
> match
> the long scale of the albumen paper that they were printed on. If  
> you make
> a collodion negative and skip intensification, it will print very  
> nicely
> on modern silver gelatin papers.
>
> But, it sounds like the OP wants to make ambrotypes in the darkroom  
> under
> an enlarger. I've had people do this in workshops and it works  
> quite well.
> You need a positive image to enlarge from, of course.
>
> Kerik
> www.kerik.com
>
>
>> Wet-plate collodion ("WP") tends to make negatives with a
>> substantially longer density range ("DR") than the exposure scale
>> ("ES") of most enlarging-speed printing materials, and IME the
>> process does not respond well to "minus" development (the usual
>> technique for reducing the contrast of film negatives).  You have
>> choices -- for example, you could make printing masks for the
>> collodion negatives, but punch presses tend to make a mess out of
>> glass plates (<g>) and achieving alignment manually will make you
>> want to go make daguerrotypes over an open dish of hot mercury in an
>> unventilated tent.  So, my advice would be to focus on solutions
>> other than enlarging wet plate negs.
>>
>> On the other hand, I don't much see the point of making wet-plate
>> collodion negatives just to scan them or print them on enlarging
>> materials -- there isn't much "look" to WP negs, aside from the long
>> DR and blue [only] sensitivity (which can be duplicated with a blue
>> filter).  Of course, "just to do it" is a perfectly legitimate
>> justification.  However, may I suggest that you also take up Pt,
>> albumen, or collodion paper printing while you're at it?  Those are
>> the printing media that were in use by the folks who originally  
>> made WP
>> negs.
>>
>> Best regards,
>>
>> etienne
>
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