Excessive fog on HP5 with Pyrocat-HD???

[Bob Farr]

Just finished a film test with Ilford HP5 using Pyrocat-HD [1:2:100] at 75 degrees in BTZS tubes for 4, 5.5, 8, 13 and 18 minutes. All had excessive fog, from 0.31 to 0.65 on step 21 with the Stouffer step tablet. Previous tests had 0.09 to 0.20 on step 21. The film was purchased in late November and the developer mixed in mid December. In my panic the first conclusion is that UPS may have x-rayed the film when I shipped it home after a photo trip. The densitometer was re-calibrated and gave the same readings from the earlier tests. Are there any other factors that I may have overlooked?? Thanks!!

[Cor]

Hi Bob,

HP5+ and PyrocatHD does raise B+F in my hands too, but I never measured, I just printed through it. Lately I switched to Mytol (Xtol) and have visually lower B+F, you might want to run a negative through another developer..

Best,

Cor

[Gem Singer]

In all likelyhood, UPS did not X-ray your film.

After using Ilford DD-X to develop HP-5+, I switched to Sandy King's Pyrocat-HD a few years ago.

Pyrocat-HD is a staining developer and imparts a light "tobacco" colored brownish stain to HP-5+.

Perhaps that's what you are interpreting as "fog".

Also, try developing at 70-72F and using 1 part A+1 part B +100 parts water.

Use test times from 7-11 minutes at 1 minute intervals.

Developing with BTZS tubes is continuous agitation. Pyrocat-HD responds best to intermittent agitation.

[tautatis]

You have received great advice in this thread. Here is mine.

I develop my negatives using Pyrocat-HD using 1:1+100. I use mostly slow films such as Efke 25 and 50 PL as well as Adox CHS 25 Art. I develop my negatives at between 75 to 80 degrees using a Uniroller base and drum for 10 - 13 minutes (depending on the shooting conditions).

I try to keep detailed field notes to take advantage of the developer's optimal capabilities. So far am very happy with the negatives I have developed.

Enjoy,

Tautatis.

[Bob Farr]

Hi,
Thanks for the replies and helpful suggestions. It's very likely that the film I used for the test on Jan. 2nd was sent through checked baggage and very likely x-rayed. I'll run another test today on film that was not in checked baggage. What really got my attention was the fog level on yesterdays film test. Comparing yesterdays fog level of 0.31 at 4 minutes developing on step 21 with a test from last Oct. with a fog level of 0.09 at 4 minutes on step 21.

So, the lesson is to be more careful with film testing and shipping??

Bob

[Daniel Stone]

I think the main thing to look out for in the future Bob is to not put any film in checked baggage, just carry on. That's if you did put it in the hold.

[Jay DeFehr]

Bob,

A fog test is pretty simple; just process an unexposed sheet and measure the density. When you subtract this figure from your measured 21 step results, you should be in the neighborhood of your earlier test.