Originally Posted by Ian Grant
My own experiences with Pyrocat HD (sodium carbonate version used 1+5+94) suggest that developing times for varied films vary quite a lot. When I started using Pyrocat I used Sandy Kings graphs which he included in his article posted on www.unblinkingeye.com. I found my negatives to be quite under developed. I think I have finally got my times locked down to the following: -
HP5+ 320iso 17minutes
FP4+ 100iso 14 minutes
Adox CHS100 80iso 8 minutes (2+10+88)
Efke R25 18iso 10 minutes (2+10+88)
Kodak Verichrome Pan 100iso 9 minutes
I have some Fomapan 100 and ERA 125 in the freezer but have not tried it yet. Many of my subjects have an SBR of only 4 stops. I would be grateful to know what your standardised time it.
I have stopped using Prescysol EF simply on the grounds of economy. I used to use it at double strength for 10.5 minutes to get the necessary punch in my negatives. I found it lasted about 6 months once opened.
Adrian, I use the Potassium Carbonate version of HD and standardise at 1+1+100 for 120 & 5x4, with an occasional roll of 35mm.
My times for HP5 (EI320), Delta 100 (EI64) & 400 (EI320), Acros (EI100) and EFKE PL25 (EI50) are 15mins @ 20°C with inversion agitation. However in the Summer I process at 26-27°C it can be 40°C+ outside at times so I process to match the tap water temperatures and reduce the dev time to compensate. Fomapan 100 & 200 I process for 11 minutes and shoot at half the box speed, that tames their inherent contrast perfectly.
For my 10x8 tray processing I use 2+2+100 with EFKE PL25 at 50EI processed for the equivalent of 9 minutes at 20°C.
I'm shooting mostly in the almost constant bright sunlight here in Turkey and the murky dingy weather when in the UK and have found little need to make exposure/development adjustments to compensate. While I use the Zone system I don't do N+ or - 1 adjustments and only N+ or - 2 when really needed/wanted. I don't necessarily want my images shot in foogy (UK) conditions to have a full contrast range.
I think the film that astounds me in Pyrocat HD is LF HP5, it's my film of choice now here in Turkey where I often have to shoot 5x4 hand-held, gives me 1/125th @ f22, your time's etc are not far different :D
Your EFKE/Adox speeds seem low though, their Box speeds are actually for Tungsten light where their reduced red sensitivity causes greater speed loss compared to most films. Jessops sold EFKE as own brand for years at double the ISO/
I've found that the issues of developer like Pyrocat and Prescysol deteriorating are usually linked to the type of plastic bottle used, and the Prescysol bottles aren't ideal. Oxidised Pyro devs like Prescysol or Pyrocat can cause uneven staining so even though a negative can look OK visually you can get unexpected patchiness when printing (or scanning), so once a developer turns colour it should be discarded. PMK is worse which is why it isn't used for Rotary processing where aerial oxidation exacerbates the problem
A tip making up Pyrocat is make sure your Metabisulphite is reasonably fresh the dev keeps 18 moths (even here in Turkey) in a part filled bottle (in use) if it is fresh, and Pyrocat only start to oxidise once the dissolved SO2 from the Metabisulphite is depleted.
I switched back to XTOL / D-76 last summer as I found Pyrocat-HD unreliable with rotary processing; although more recently I've been processing 120 B&W film in stainless steel tanks so some of the problems may relate to rotary processing work flow issues.
Thank you for taking the trouble to respond. This is really useful information. I had no idea that the speeds for Adox CHS are for tungsten lighting. It would explain Jessops R200 which a knew was Efke but I also knew that Efke did not have a 200 iso film in their inventory.
I have now processed six sheets of Fomapan 100 in Pyrocat HD at the times and speed used by Ian given in a previous post. I have to say they are bang on giving negatives that are easy to print on grade 2 - 2.5 in a diffuser enlarger.
Sadly 5 out of six of the shots have negative defects. I have heard about variable quality with Fomapan 400 but I did not know that the 100 was susceptible as well. I would be grateful if anyone using this combo had had to take any special precautions other than careful consistent technique. Ilford negatives processed on the same day did not exhibit any defects. I should point out that I use distilled water when formulating the stock solution but make up the working solution using tap water.
Ever try Nymoc in Toronto? Check the archives for location detals.
Originally Posted by rdstoker
Sadly 5 out of six of the shots have negative defects. I have heard about variable quality with Fomapan 400 but I did not know that the 100 was susceptible as well. I would be grateful if anyone using this combo had had to take any special precautions other than careful consistent technique. Ilford negatives processed on the same day did not exhibit any defects. .[/QUOTE]
Sadly too, I gave away 25 rolls of unused Fomapan of various types and sizes to the local school and went back to using Ilford, Fuji or Kodak. There were too many shots ruined by emulsion faults with the Foma that I tried.