[alt-photo] Re: New Platinum Prints

[David Hatton]

Etienne,
Take a look at these Platinum prints. Printed recently from glass
negatives exposed in 1911. I think they are really beautiful examples
of the genre..
http://www.ponting-portfolio.com/home.html

Regards
Davidh

On Sat, Apr 10, 2010 at 11:37 PM, David Hatton
<davidh6180483 at googlemail.com> wrote:
> Etienne,
> Thanks for replying. Just so I understand what you're saying. The
> curve I apply to my digital negative is actually destroying some of
> the image content of the scanned negative? If so, why do we apply a
> curve at all? Why can we not merely print the negative as it is
> scanned? Assuming of course that the original negative is correctly
> developed for platinum? I'm sorry if I sound stupid but I find this
> very confusing at the moment :)
> Regards
> Davidh
>
>
> On Sat, Apr 10, 2010 at 11:09 PM, etienne garbaux
> <photographeur at nerdshack.com> wrote:
>> Davidh wrote:
>>
>>> This is something that's been concerning me lately. I've been
>>> preparing my negs for palladium digitally using Mike Wares method. The
>>> reason for this is that my printer (Epson 1400) won't allow me to use
>>> any other method as the inks are not very dense. I manage to get
>>> satisfactory gum prints but I'm thinking I could be missing out on
>>> something in my palladium experiments. My exposure time using BL tubes
>>> is 60 seconds. The prints look ok but nothing special. Could this lack
>>> of negative density have something to do with the way they look? If so
>>> why?
>>
>> Be aware that I'm not familiar with Mike Ware's method (although I have seen
>> prints attributed to it) and I do not use digital negatives.
>>
>> There are two things at work here: (i) matching the negative density range
>> ("DR") to the printing exposure scale ("ES"); and (ii) the character of the
>> exposure scale, however long or short it is.  If the DR of your negs is too
>> short to match the printing ES, you'll get low-contrast prints with murky
>> (but not very deep) shadows and/or fogged-looking highlights.  But even if
>> the negs have the right DR for the process, the characteristic curve of the
>> printing process may be ugly.
>>
>> The standard long-scale Pt process has a very, very long linear scale with
>> symmetrical, gently rounded toe and shoulder, typically printing the whole
>> step wedge with some scale left over.  Therefore, you need to use negatives
>> with a very high DR to obtain all of the available print zones with this
>> process.  Photographers have not typically made negatives this "bulletproof"
>> since the late 19th Century, so folks have tried a number of different
>> methods to shorten the Pt exposure scale (adding dichromates, hydrogen
>> peroxide, etc., etc.).  These tricks shorten the exposure scale by raising
>> the threshold exposure -- not really a very promising way to go about it.
>>  Anybody who has done serious sensitometry with the process has seen the
>> ugly characteristic curves the short-scale versions of the Pt process
>> produce.  I have yet to see prints made using any short-scale Pt process
>> that came close to the look of "real" (long-scale) Pt prints.
>>  Unfortunately, so many workers are using the short-scale processes now that
>> many people don't even know what a good Pt print is supposed to look like.
>>
>> I commend to you an experiment:  Make some in-camera negatives with a DR
>> above 2.1 (try to hit 2.4 for starters), and print them using the standard
>> full-scale Pt process.  I bet you never go back to digi-neg Pt printing
>> again, and depending on how big you think prints need to be, that you
>> acquire one or more LARGE format cameras or learn to make good enlarged
>> negatives in the darkroom (not so easy now that slow, blue-sensitive copy
>> films are long gone).  If you have no option besides digital, have a service
>> bureau make some 2.4 DR negatives with an imagesetter using your files.
>>
>> Best regards,
>>
>> etienne
>>
>>
>>
>>
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