Pyrocat HDC aerial oxidation?

[Lemale]

Hello,

Need help
I've mixed one liter of pyrocat HD in glycol and I'm getting strange steaks, mainly in highlights.

This one developed 1:1:100 @24celsius, extreme low agitation, 4cycles, first 1min, later three cycles 10sec each , total 14min.
Fomapan 200@100. (I emphasized those steaks in photoshop)
Was searching forum with no luck and recently read in Anchels cookbook, that it could be aerial oxidation, but no examples in that book.

Should I increase part A dilution for example 30%?

Another example, this one more extreme, but it was tray developed

Thanks in advance for your oppinions !

 

[Lemale]

any ideas? please please

 

[LarsAC]

The upper left in the first image looks like dry marks from water to me. How do you dry the negatives ? Can you give a more detailed description of your development process (start to end) ? I would change to a more vivid agitation scheme, e.g. constant agitation (reduce development time by 30% or so). This will give you a quick reference, whether agitation may be the problem. Many development issues discussed here in the past were related to agitation in one way or another.

The second looks like it was not fully covered with developer in the tray.

Lars

 

[Vaughn]

Edited: Pyrocat HD is not as well designed for stand/low agitation methods as Pyrocat MC. Perhaps that might help.

http://www.pyrocat-hd.com/

 

[Alan Johnson]

I'll take a guess - uneven wetting of the emulsion at the start of development. The suggested cure is to presoak in water for about 3 min with some agitation and then agitatate again when the presoak is first replaced by developer, then proceed with the reduced agitation as before.

 

[Rick A]

Pyrocat-HD was designed for rotary processing, not low agitation. IMO, minimal agitation schemes are exalted by people too lazy to follow instructions. My recommendation, follow directions, use the product how it was intended, and if not, don't whine about having issues.

 

[Andrew O'Neill]

Sorry but I don't really follow your agitation regime. Pyrocat-HD is an excellent semi-stand developer. Very risky for stand, though.

 

[Gerald C Koch]

Pyrocat-HD was designed for rotary processing, not low agitation. IMO, minimal agitation schemes are exalted by people too lazy to follow instructions. My recommendation, follow directions, use the product how it was intended, and if not, don't whine about having issues.

+100

Highly dilute developers are subject to aerial oxidation. With stand or semistand development they are also subject to bromide drag.

 

[Ian Grant]

Just use the developer properly with reasonable agitation, you'll get results similar if not better to the advocates of minimal or stand developer.

Foma films are great, I use them, however they will be the first to show processing faults with poor technique as they build up contrast raidly and need much shorter development times.

Ian

 

[Andrew O'Neill]

Pyrocat-HD was designed for rotary processing, not low agitation. IMO, minimal agitation schemes are exalted by people too lazy to follow instructions. My recommendation, follow directions, use the product how it was intended, and if not, don't whine about having issues.

I disagree. I've been using it for low agitation for years with excellent results. And I don't consider myself too lazy to follow instructions. Your comment is a tad harsh, no?

 

[LarsAC]

I would try a classic agitation scheme to exclude this as a possible cause.

Once you have a proper starting point, change one parameter at the time until you have what you want.

Lars

 

[Lemale]

[QUOTE="The upper left in the first image looks like dry marks from water to me. How do you dry the negatives ?
..............
The second looks like it was not fully covered with developer in the tray.
Lars[/QUOTE]

Thanks for reply, I've dry them in room temperature, just leaving standing holder of combi-plan's tank. These streaks are also on other negs from the same developing batch, on the side where I was pouring developer to tank.
My agitation scheme is constant tank inversions for the first minutes, second is 10sec after 3mins, next is 10sec after 4 mins, and last is 10sec after 4 and half minutes and left standing still. Total time 15min, temperature 23celsium

 

[Lemale]

Sorry but I don't really follow your agitation regime

I agitate constantly for the first minute, then agitate every 3mins for 10sec. total development time ~15mins@23celsium

 

[Doremus Scudder]

I don't know if the problem lies with your agitation scheme at all. It seems to me that your negatives are getting contaminated/unevenly wet at some stage before developing. The likely culprit is carried-over fixer from one source or other. I'd make sure your work surface is really clean, make sure everything is pristine when unloading the holders and loading the tank. That includes ensuring the tank is clean and dry. Hands are a common source of contamination. Wash thoroughly and dry. If you wear gloves, make sure they aren't compromised and that they are clean before unloading. The only time I ever got results like yours was when I had a pinhole in a glove that allowed water and chemicals in. I didn't notice before unloading the next batch without changing gloves. Even though the gloves seemed clean and dry to me, the small hole in one fingertip leaked chemicals onto the film causing spots.

Do, however, run a batch with a regular agitation regime to eliminate that as a possible cause.

Best,

Doremus

 

[Andrew O'Neill]

I agitate constantly for the first minute, then agitate every 3mins for 10sec. total development time ~15mins@23celsium

Got it. Thanks.

 

[Dennis S]

I don't know if the problem lies with your agitation scheme at all. It seems to me that your negatives are getting contaminated/unevenly wet at some stage before developing. The likely culprit is carried-over fixer from one source or other. I'd make sure your work surface is really clean, make sure everything is pristine when unloading the holders and loading the tank. That includes ensuring the tank is clean and dry. Hands are a common source of contamination. Wash thoroughly and dry. If you wear gloves, make sure they aren't compromised and that they are clean before unloading. The only time I ever got results like yours was when I had a pinhole in a glove that allowed water and chemicals in. I didn't notice before unloading the next batch without changing gloves. Even though the gloves seemed clean and dry to me, the small hole in one fingertip leaked chemicals onto the film causing spots.

Do, however, run a batch with a regular agitation regime to eliminate that as a possible cause.

Best,

Doremus

I have noticed with using PMK or Pyrocat HD that I have to mix the A&B separately in containers that I only use for PMK or Pyrocat. Even use separate stirs sticks that are never exchanged. Keeping the temps at 20 or 21C and I never had a problem until I discovered my Sodium meta-Bisulfate was going south on a mixed batch that I had. I did purchase that online, so God only knows how old it really was so a quick trip to a wine making shop and I am back with fresh chemicals and the Pyrocat that works as well as it ever has. I use the Pyro developer on all the films I have been using and just love the negs that I get from these developers.

 

[greg zinselmeier]

For HD , and HDC. Semi stand works extremely well. 2 inv. Every 5 seconds for 1st minute, then 2 inv. Every “time” interval. Usually a minimum of 3 intervals are required. You will need to test for total time. Divide total time by three. Presoak for 2 minutes. Dump. Refill with same temp water as dev. For 2 min. Dump. Then add developer.

 

[Dennis S]

Good points as Pyrocat developing doesn't need much agitation except for PMK which needs it every 15 secs on some films. After developing I rinse it 2 or 3 times with water the same temp as the developer as I never use stop bath and then use TF 4 fixer.

 

[greg zinselmeier]

I only recommend semi stand for document and arial films!! When you are controlling highlight build up, while allowing shadow to develop more! However, Generall purpose films agitation every minute. Follow the instructions please K.I.S.S.

 

[Dennis S]

I only recommend semi stand for document and arial films!! When you are controlling highlight build up, while allowing shadow to develop more! However, Generall purpose films agitation every minute. Follow the instructions please K.I.S.S.

All depends on the water you mix it with as here it is soft water and I know agitating that much I had only blacks and whites with way too much contrast and very little grey scale left. Pyro needs definitely a test to find your proper time and agitation sequence. I use Fomapan film any size mostly in Pyrocat semi stand with impressive results every time.

 

[greg zinselmeier]

Ya, I can see that with foma . Good call.

 

[Dennis S]

I do my Orwo N75 & N74 as well as Delta 400 with this method but for some reason the Orwo UN54 develops pinholes when I use Pyrocat to develop it. There have been posts here about that problem also and what I tried was ordering a 400' roll from Germany so I knew it had to be fresh but still pinholes.