Re: URL for platinum gum comparison

Agreed. I'm sure of this (that a print rivaling the tonal scale of
platinum can be achieved with two gum coats) from my own experience,
but have never done a direct side by side comparison with platinum,
so will look forward to seeing yours.

What I don't understand (and this goes with the usual caveat that
looking at jpeg rather than actual print makes any interpretation
tentative) is that the print that's made with the "correct curve"
seems grainier than the print made with the same coating mix but a
different negative. I can't think of any logic of the gum process
that would explain why that should be so.
Katharine

On May 1, 2006, at 8:21 AM, Dave Soemarko wrote:

> And it is not just the matter of tonality either. If it were, we
> can adjust
> the tonality/curve either digitally or by positive/negative masking
> in the
> traditional way.
>
> But the fact is that when you do a gum print (at least a
> traditional gum
> print with analog negative), somewhere after the midtone and near the
> highlight, you get grainy effect. Depending on the paper and
> sizing, the
> grainy effect might not be too pronounced (so I don't mean very rough,
> coarse effect, but the effect can be seen). This is because of the
> gum layer
> is near the top of the tooth (or top of the "punk hair" using the
> model that
> I used before. The tooth or punk hair does not have equal length
> like a true
> nicely trimmed punk hair, but I will get to this later in the summer).
>
> You can see this grainy effect even in a simple print using a step
> tablet.
> When one see that, one can tell already that a single coat gum
> cannot show
> the same look as Platinum because the difference is not only on
> tonality but
> on graininess as well (and I am not saying which one is better
> because that
> depends on the object/purpose of the printing and personal
> preference. I am
> talking talking about the technical side of it).
>
> However, if one understands the concept of duotone and have control
> of it in
> gum process, I believe one can achieve the same tonality and the
> same (or
> perhaps almost the same) smoothness with gum compared with Platinum.
>
> When I setup my printing environment again, I will ask if Pt/Pd
> printer
> might be interested in a test. What I will need is an original
> negative from
> you (one that have full tone but is not so important for you (just
> in case
> there is a loss) and preferably one that you have a duplicate) and
> a Pt/Pd
> print from you. If you are interested, please let me know (either
> now or
> then).
>
>
> Dave S
>
>
> -----Original Message-----
> From: Christina Z. Anderson [mailto:zphoto@montana.net]
> Sent: Monday, May 01, 2006 11:05 AM
> To: alt-photo-process-l@usask.ca
> Subject: Re: URL for platinum gum comparison
>
> Positively--I decided that until I had a carbon print for
> comparison, I
> would choose the process that would make gum look the worst and
> compare, to
> weight the comparison away from gum. The other reason for using pt/
> pd is
> that it gives such an incredibly long tonal scale, especially in the
> highlights where it shines and glows with delicacy, it would be a good
> indication of long tonal range to compare with a short tonal range
> process.
>
> I can get with both salt and pt/pd close to 31 steps on a 31 step
> tablet,
> where gum is somewhere between 9 and 12.
> chris
> ----- Original Message -----
> From: "Yves Gauvreau" <gauvreau-yves@sympatico.ca>
> To: <alt-photo-process-l@usask.ca>
> Sent: Monday, May 01, 2006 8:58 AM
> Subject: Re: URL for platinum gum comparison
>
>
>
>> Christina,
>>
>> the platinum print doesn't seem to have the same texture (none) as
>> the
>> other prints which makes it a bit difficult to compare don't you
>> think?
>>
>> Regards
>> Yves
>>
>>
>> ----- Original Message -----
>> From: "Christina Z. Anderson" <zphoto@montana.net>
>> To: "Alt, List" <alt-photo-process-L@usask.ca>
>> Sent: Monday, May 01, 2006 8:45 AM
>> Subject: URL for platinum gum comparison
>>
>>
>>
>>> http://www.loris.medici.name/Christina_Anderson/
>>> Gum_Platinum_Compare.
>>> jpg
>>>
>>> Here 'tis.
>>> Chris
>>>
>>
>>
>>
>
>
>
>
>
>
Received on 05/01/06-11:14:54 AM Z