Jobo 2521 processing ?s

[billdlv]

I recently purchased a Jobo 2521 tank to process 4x5 film. Previously I tried a yankee agitank and did not like the results of the negatives which had a lot of uneven development. Plus the agitank required a lot of chemistry.

I tried the Jobo for the first time with Ilford FP4 125. I used Clayton F60 developer at 68 F. I put the emulsion side of the film towards the center of the tank. I filled the tank with 560 ml of 1:9 developer. I inverted 2 times and rapped the tank and began rolling the tank back and forth on the counter, 1 revolution in each direction about every second throughout the 5.5 minute development time which is what the chart indicated.

The negatives came out without spots and appear to be evenly developed with adequate density. However they are extremely flat with very little contrast. The shots were taken in bright sunlight outside using sunny f/16 exposure.

I don't develop a lot of 4x5 film and would like to continue to use the Jobo tank manually. I have done tray development but it uses a lot of chemistry and I would prefer to develop in the light.

I would appreciate any suggestions or ideas.

Bill

[Jay DeFehr]

Hi Bill.

If your negatives lack contrast, develop longer, and if they're too dense, decrease exposure.

Good luck.

Jay

[merlo.luca1961@libero.it]

Your are getting flat negatives since the liquid inside the tank does not get enogh agitation. Note that these Jobo tanks have been conceived to be used with an automatic machine and the gratest annoyment is that the lid of the tamk is protruding and renders the manual rotation on a plane very awkward. In order to prevent this get the attachment 2560 that will transform your 2521 tank in a tank that can accomodate 3 reels and proceed rotatng the tank. The other advantages of using this system are indicated in my other post I sent today.

Ciao from Italy

[billdlv]

Thanks for the tips.

I did some research and looked at the manual for the 2521 tank and I noticed that Jobo states that you should do a 5 minute pre-wash with water. I assume that they mean pre-soak with agitation. I know that pre-soaking Ilford does increase contrast so maybe next time I will try a pre-soak.

I also read that the Jobo processor rotates back and forth at 70 rpm (?); maybe I need to roll back and forth faster.

Merio I looked at the 2560 module but it will require me to use more chemistry and I don't want to do that if I can avoid it. I am thinking about making a ring to make the tank sit flat on the counter to make it easier to roll.

Jay I was thinking that too, but I would have to experiment with the development times. I am also thinking about using D-76 because I think its better than my Clayton F-60 (which works well with 35mm film IMHO). I'd rather not mess with the exposure at this point, I am still trying to become proficient using my camera first. I'm using BDE for exposure; later hopefully I will start using the zone system.

If anyone else has any tips or suggestions I would appreciate them.

Bill

[Neal Wydra]

Dear Bill,

Purchase a CPE-2 on ebay. If they seem pricey, look for one without a lift. It's nice, but not necessary.

Neal Wydra

[billdlv]

Neal I was looking on e-bay and there are some that are not too expensive.

I was hoping to avoid having to spend more $$ and also finding space to store the unit when I am not using it. I saw one in Freestyle's store and they are pretty big.

Thanks,
Bill

[Jan Pedersen]

Bill,
I use a 2521 manually but use 1400ml of fluids instead of the minimal amount for rotation.
Did in the begining as you put the emulsion side towards the center but changed that when i realized that those small taps on the inside of the reel made small undeveloped marks on the film.
I always agitate by kipping as i do with 35mm and 120, one full minute in the beginning and then 3 kips every minute for the remainder unless minimal agitation is used.
I don't roll as the tank is designed fore but rotate it as i kip. Have no problems with uneeven developement. Give it a try, i think it will work for you.

jan

[billdlv]

Jan thanks for the information. I guess if the drum is not agitated as designed it makes sense to put more chemistry in it.

I don't understand what you mean by kip; is that an acronym?

Thanks,
Bill

[Jan Pedersen]

Bill, actually don't know where that term came from but by "kip" i mean turning the tank over instead of rolling and at the same time slightly rotating so when i have done 3 turn over i have also done about one rotation. Hope that you can visualize this?
No matter what procedure you end up doing i think it is most important to be consistent in what you do and then adjust dev. times accordingly.
Good luck.