JOBO Blues

[bob carnie]

For PMK 14 min dev I use a 2 min pre soak and split the dev into two 7 minute times, I mix 2000ml of pyro and put 1000ml in each bottle.
FWIW I always use 1000ml for all tanks and runs , I never break it into small amounts of fluid.
If you are getting streaking you are pouring too slowly and the film is not getting the dev evenly enough fast enough.

[Lenny Eiger]

Jobo's recommended amount for b+w chemicals is 1000ml for 5 sheets. That's from the link I provided above.

Vinny,

Thanks for the link. I never considered a two part presoak. Interesting idea...

I think I would add the important recommendation here would be from the film and developer manufacturers data on the amount of developer required to develop the number of square inches of film. That's how I calculated it... and why certain developers, which might be good by other criteria, are not of interest (Perceptol isn't going to do 5 sheets of 8x10, for example).

(I really don't care what Jobo says, they have proven to be incorrect and unreliable in this regard...)


Lenny

[Nicolasllasera]

Ooohh. I guess I took the quantity fromthe E6 and C41 and stuck to that. Should I go up to 1000ml? Or if its working stay at 640ml. Im using home made D76.

[Scott Davis]

I would skip the PMK and switch to a pyro developer meant for rotary development, like Pyrocat HD or 510 pyro or Rollo pyro. I had bad experiences when trying to use PMK in rotary development; as a result I switched to Pyrocat HD and could not be happier. Another plus of the switch is that you don't have to add an extra stop to your exposure to compensate for the developer's relatively weak activity in the shadows.

[vinny]

Lenny- two batch developer, not pre-soak.

I would skip the PMK and switch to a pyro developer meant for rotary development, like Pyrocat HD or 510 pyro or Rollo pyro. I had bad experiences when trying to use PMK in rotary development; as a result I switched to Pyrocat HD and could not be happier. Another plus of the switch is that you don't have to add an extra stop to your exposure to compensate for the developer's relatively weak activity in the shadows.

I read "you can't use pmk in rotary machines" when I got my jobo as well but it's what I had so I tried it anyway. Best negs ever. I've been using pmk in jobo drums for about five years. No problems, no weak shadows (I don't compensate a stop, I rate tmy at 400, fp4 at 100, and efke 25 at 25. Care to elaborate on your bad experiences?

[bob carnie]

Geeze I should inform my clients, I have ran over 50 thousand rolls of PMK on a jobo over the last 20 years.. shit I am in real trouble here.
I hope I do not have to give them their money back.

I would skip the PMK and switch to a pyro developer meant for rotary development, like Pyrocat HD or 510 pyro or Rollo pyro. I had bad experiences when trying to use PMK in rotary development; as a result I switched to Pyrocat HD and could not be happier. Another plus of the switch is that you don't have to add an extra stop to your exposure to compensate for the developer's relatively weak activity in the shadows.

[Scott Davis]

I read "you can't use pmk in rotary machines" when I got my jobo as well but it's what I had so I tried it anyway. Best negs ever. I've been using pmk in jobo drums for about five years. No problems, no weak shadows (I don't compensate a stop, I rate tmy at 400, fp4 at 100, and efke 25 at 25. Care to elaborate on your bad experiences?

What I did was use I want to say 500 ml of PMK for doing 6 sheets of 4x5 in a Jobo 3006 drum. This was a good 8-10 years ago, and I don't have notes about what I did back then in front of me (don't have notes about it period), but I do recall getting a batch that were significantly underdeveloped, and the developer poured out very dark. Next I tried using a much higher volume of developer (at least 1500 ml) and ran into the problems Richard was having with overdevelopment and inconsistency. There are any number of variables that I could have been screwing up at the time and am totally unaware of now given the passing of time (I was also new to rotary processing at the time, and using an elderly CPA2 whose motor was starting to fail). I probably have discussion threads over on APUG from that time period and/or private messages relating to it that I could search through given enough time. Lee Carmichael was the one who prompted me to try Pyrocat HD instead of PMK (RIP, Lee), and to me it was a profound difference, so I was happy to change.

[photobymike]

2500ml, are you nucking futs? ]

LOL your funny vinney..

There seems to be a large number of photographers on LF that are struggling with developing there film. I have seen many of posts like this with a lack of knowledge on how to develop film of any kind. I have answered many personal emails asking for advice on how to make good negatives... Maybe there is a place online to refer the developer newbies. There are many different techniques to developing good negs. There are some basics that if followed with some common sense can cause success and satisfaction. Wish i just had the time to maybe do some videos or a website on how to do..... 2500ml lol lol.... that sure would be a heavy tank to roll....

Here are some some notes and observations in my 47 year journey to make quality negatives

I have been using Pyrocat HD Glycol with with delta 100 and 400 as well Tmax 100 and 400. And depending on what i am shooting i always over expose by at least a half stop and as much as a full stop on portraits ....


1. Use pipettes to measure. This stuff is so concentrated that being off a small amount effects your out come.

2. I presoak for 5 minutes at development temperature. I change out the water 2 or 3 times for the presoak. It is needed to wash away the halation barrier. This has always been important... use distilled water... the PH is slightly acid which is ok... tap water who knows what it is.....

3. Use rubber gloves when handling this substance. If you use it a lot, it can accumulate in your system and be toxic.

4. Use distilled water for mixing. I use distilled water for all of my photo chemicals anyway.

5. The negatives scan really well with my scanner V750 epson. I seem to have a longer dynamic range by at least one stop.

6. I use a Beseler roller for development... but it seems to like stand alone tank with moderate agitation...twirl the reels in my paterson tanks.....4x5 always are rolled....

7. Dilute your Stop Bath... to strong and you get pin holes. Use a stop bath to get the film ready for the acid in your fixer. Some photo guys use just water for the stop bath... but i have found that just a little acid stop works better. i use alkli fixer especially for T-grain films.. for an extra 3 minutes. I have also used Kodak rapid fixer without the hardener works well. Fix for an extra 3 minutes for a total of 8 minutes

8. When you get ready to mix your developer. Roll your bottles of concentrate before using... there seems to be some separation and precipitate on the cap after sitting for a couple of days. Do not shake but make sure concentrate is mixed.

9. Because of the tanning (hardening effect) of the developer it seems the emulsion needs more washing than normal film.... i use very strong hypo clear (Orbit) for 2 minutes each in 2 baths with vigorous agitation.

10. I take the film off the reels and soak for 30 secs in Photo-Flo. Most important; I use distilled water to mix Photo-Flo. If you use regular water or tap water you will see a sledge or slim on your finished negs... The i use a very clean sponge to wipe away the excess Photo-Flo.

I do all of this and what i end up with is beautiful chocolate colored negatives that scan really well.

Any thing to add to these observations, or maybe some questions.

[RPippin]

Vinny, I looked at your link and followed your procedure to the letter and I'm happy to report the next 5 negs came out perfect. Not only that, but it appears that I'm not over exposing my negs after all. In the past there appeared to be to much density in my negs but apparently it was from my developing, not exposure. Thanks for your help.

[jonreid]

your 3005 holds 6 sheets?

Maybe mine is a 3006? Takes 4x5 & 5x7 - six sheets.