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Trevor Crone
22nd June 2009, 01:25 PM
While researching processing Delta 100 in Pyrocat-HD I noticed this;

http://www.digitaltruth.com/devchart.php?Film=Delta+100&Developer=Pyrocat&mdc=Search

I think 45 minutes seems excessive? Even using the stand method I think this would be on the long side.

I've processed Delta 400 in P-HD and found a time of 12.5 minutes at 21'C, with continuous agitation for the fist minute and 5-6 seconds agitation every 30 seconds thereafter gives me negatives that print easily on grade 2 VC papers. However I've not tried Delta 100 with this developer.

Any thoughts, experiences with this combo?

Dave miller
22nd June 2009, 03:12 PM
I also think it excessive.

I believe the times given in this chart are cribbed from the manufacturers' recommendations and later modified by photographers submitting their own, often unverified figures. At best the chart cannot be considered to provide anything more than a starting point. In this case I think that the developer will either be exhausted, or oxidised long before ¾ of an hour has passed. I would discount the information in this instance, and use the same parameters for Delta 100 as you do for Delta 400 for a test film and modify after that to suit your requirements.

Trevor Crone
22nd June 2009, 03:32 PM
Thank you Leon and Dave.

Leon, 13 minutes seems a more logical time especially with the reduced agitation (4 inversions every 3 minutes) compared to my 5-6 seconds every 1/2 minute.

Dave, I think you are right the developer will be exhausted/oxidised long before the 45 minutes are up.

Bob
22nd June 2009, 05:28 PM
This looks possibly reasonable for full-stand development (1 min continuous agitation followed by 44 mins of nothing). I have tried Rodinal at these kinds of times (20 - 60 minutes) with success but have not tried it with Pyrocat. I have heard Pyrocat recommended for full-stand development elsewhere but I can't remember what kind of times were recommended.

[Addendum: just found this in a Photographer's Formulary document on Pyrocat HD:
Sheet film in trays, semi-stand agitation: special working solution of 1 part A with 1 part B with 200-400 parts water. Agitation is for one minute at start of development, followed by 30 seconds at the halfway point. Development time for slow and medium-speed films is 40-50 minutes, 70º F. Development time for fast films is 50-60 minutes. Dichroic fog may result from extended development of high-speed films. If this is a problem in your work use a 1:1: 200 dilution and reduce development to about 30 minutes. ]

As well as the untested nature of the figures in the chart, the agitation method is never given: stand, semi-stand, continuous, Ilford or Kodak style intermittent, rotary speed, whatever - it often omits dilutions too. Makes it fairly useless in practice. An excellent idea but with a couple of basic flaws.

Dave miller
22nd June 2009, 05:54 PM
Ed Buffaloe has put together some note that may be of interest to those unfamiliar with staining developers HERE (http://unblinkingeye.com/Articles/Pyrocat/pyrocat.html)

Does anyone know of any meaningful comparison tests that have demonstrated any advantage to the use of dilute developers and long development times? I remain sceptical that any useful advantage can be obtained in a print from such practices.

Trevor Crone
22nd June 2009, 06:25 PM
Thanks Bob, I STAND corrected or semi-stand corrected at the very least:D

I've used semi-stand development in the past (120 film) but have not seen any real noticeable difference over standard developer dilution's and time. Although I must confess I've not performed any critical side by side comparisons.

Bob
22nd June 2009, 06:34 PM
There is a guy who posts on APUG (often with his monthly "special offer" on print sales) who has done such tests (with Pyrocat HD) and claims considerable edge effects but I can't remember his name. I also recall reading (and yet again, I have never tried this myself) that semi-stand does not cut it as far as edge effects go - it must be full stand development with no additional agitation after the initial 1 minute. Apparently...

Dave miller
22nd June 2009, 06:56 PM
That was my point, there is always someone that claims an advantage, but has anyone ever demonstrated a practical advantage?

Bob
22nd June 2009, 07:15 PM
He has examples on his website as I recall but as I say, I can't remember who he is...

[Addendum: OK - I just remembered his surname so I managed to track him down... Steve Sherman. On the downside, the A-B comparisons seem to have gone from his site (http://steve-sherman.com/index.cfm).

I think this (http://www.apug.org/forums/forum37/24023-semi-stand-description-illustratvie-photo.html) is the first post he made on the subject on APUG but there have been others. Apparently he has articles in View Camera magazine too but I have not seen those.
]

Dave miller
23rd June 2009, 08:09 AM
I’m still not convinced (cynic that I am) that with full stand development it’s not a case of “the emperor’s new clothes”, people seeing what they have been let to expect. If it’s so good why don’t we develop that way as a matter of course?

Can anyone on this forum claim to have used the method, and achieved beneficial results? If so, please take the time to outline your method and results.

By beneficial results I mean something that can be transferred to a finished print.

Keith Tapscott.
24th June 2009, 07:28 AM
While researching processing Delta 100 in Pyrocat-HD I noticed this;

http://www.digitaltruth.com/devchart.php?Film=Delta+100&Developer=Pyrocat&mdc=Search

I think 45 minutes seems excessive? Even using the stand method I think this would be on the long side.Trevor, there is a contact tab in the link you posted. It is probably an error and I`m sure that Jon Mided would be grateful if you pointed this out for him.