[alt-photo] Re: pt/pd differences in exposure methods

[Paul Viapiano]

Thanks, Eric...

I do keep detailed notes on everything.

I worked out the problem this morning. It seems that my latest package of 
Fabiano needs a lot more acidification than my last batch. I had one sheet 
left from the old pile and just tested it. Perfect...all other variables 
were exact.

Much thanks...your reply should be in the pantheon of troubleshooting lists.

Paul


----- Original Message ----- 
From: "EJ Photo" <ejnphoto at sbcglobal.net>
To: "'The alternative photographic processes mailing list'" 
<alt-photo-process-list at lists.altphotolist.org>
Sent: Wednesday, June 30, 2010 10:48 AM
Subject: [alt-photo] Re: pt/pd differences in exposure methods


> Paul, Over the years there has been much discussion on different exposure
> units, and everything under the sun. With not only the quality of light 
> but
> the quantity of light being important, they alone don't determine the 
> speed
> of the coated paper. The film or substrate that holds the resist, negative
> both digital and traditional, blocks UV light as does the glass. it is a
> complicated set of variables. The glass types can change their UV blocking
> characteristics while keeping the same name or label. Rigorous testing 
> over
> all the possible sources has not to my knowledge been done with certainty.
>
> You also have the moisture content, and make up of FO, AFO, and paper 
> types.
>
>
> Mike Ware did put out a paper on platinum printing many years back that 
> did
> specify yield based on certain UV output. It did hold true to my
> observations, but I never tried to match, make equivalent controls, etc.
> Best advise I can offer on that is keep notes, and use your findings for
> your specific set of contact frames, glass, negatives and ink sets.
>
> NuArc is a brand, but not a specific lamp; there are several that work.
>
> Eric Neilsen
> Eric Neilsen Photography
> 4101 Commerce Street, Suite 9
> Dallas, TX 75226
>
> www.ericneilsenphotography.com
> skype me with ejprinter
> www.ericneilsenphotography.com/forum1
> Let's Talk Photography
>
> -----Original Message-----
> From: alt-photo-process-list-bounces at lists.altphotolist.org
> [mailto:alt-photo-process-list-bounces at lists.altphotolist.org] On Behalf 
> Of
> Paul Viapiano
> Sent: Tuesday, June 29, 2010 6:28 PM
> To: The alternative photographic processes mailing list
> Subject: [alt-photo] Re: pt/pd differences in exposure methods
>
> No, Jeremy, I don't.
>
>
> ----- Original Message ----- 
> From: "Jeremy Moore" <jeremydmoore at gmail.com>
> To: "The alternative photographic processes mailing list"
> <alt-photo-process-list at lists.altphotolist.org>
> Sent: Tuesday, June 29, 2010 4:24 PM
> Subject: [alt-photo] Re: pt/pd differences in exposure methods
>
>
>> Paul, do you have a densitometer to measure the difference in reflective
>> dMax?
>>
>> On Jun 29, 2010 5:44 PM, "Paul Viapiano" <viapiano at pacbell.net> wrote:
>>
>> Has anyone compared exposure methods and the differences in results?
>>
>> I seem to get deeper blacks when exposing in the sun than using the 
>> NuArc.
>> Even using a separate custom curve for each method, the sun gives me a
>> better black, more contrasty result...
>>
>> Don't get me wrong, the results are very good, but the edge goes to the
>> sun
>> prints.
>>
>> Paul
>> _______________________________________________
>> Alt-photo-process-list | http://altphotolist.org/listinfo
>> _______________________________________________
>> Alt-photo-process-list | http://altphotolist.org/listinfo
>
> _______________________________________________
> Alt-photo-process-list | http://altphotolist.org/listinfo
>
> _______________________________________________
> Alt-photo-process-list | http://altphotolist.org/listinfo