Developing film in jobo 2820 test drum

[WootSK]

Hi, I have a 2820 test drum and recently read some discussion about developing film in print drum (http://www.largeformatphotography.info/forum/showthread.php?t=25646&page=2). I tired using it to develop films, but sometime my wing clip will fall off during developing. It also blocks chemical from reaching the spot with the clip and cause a small dot on the film. Anyone has any idea on developing without the clip? They wrote something about a "blanket", but I am not sure what it is.

[Lachlan 717]

What format are you trying to develop?

Have you had a look at Jobo's site where there is a diagram to show how to load sheets relative to the ribs inside the tank?

[Denis Pleic]

They wrote something about a "blanket", but I am not sure what it is.

The "blanket" is described here (http://www.galerie-photo.com/porte-film-jobo.html): if you take a look at that web page, you will understand what is a "blanket": it's a piece of flexible plastic on which you place the negative(s), and then roll everything and insert the whole thing in the drum.

[ic-racer]

2820 holds only two 4x5 sheets. If you use the clips for loading, after the film is loaded, take the clips off. That keeps them from coming off and possibly causing a problem.

I have had good luck with mine for the few times I need to see a 4x5 sheet right away.

[Scotty230358]

The 2820 test drum has the same body as the 25 series developing tank. This allows you to use 2509n reels allowing you to develop 6 sheets at one time.

[Lachlan 717]

The 2820 test drum has the same body as the 25 series developing tank. This allows you to use 2509n reels allowing you to develop 6 sheets at one time.

Have you tried these without the centre column? There is a locking lug on the column to ensure they spin with the tank. Without these, the reels might not spin well.

[WootSK]

Thanks for all the help. After some thinking, I tested pre-loading with some clips that has no wings and slide my films into the slot for 4*5. It works and and doesn't falls off. The important point is that unlike the wing, it doesn't blocks the chemical from reaching my film. Sadly I wasted a nice photo due to the wing clip.:( Taking it easy as lesson learned and I will load new drum and test with water before using on actual films.

[WootSK]

The site for the blanket seems like a very good idea and I am thinking of DIY one when free if they don't sell it outside.

[Jehu]

Have you tried these without the centre column? There is a locking lug on the column to ensure they spin with the tank. Without these, the reels might not spin well.

I just tried the 2820 Test Drum with the 2509 reel. I DID have the center column. The result was excellent. No mottling, even development. I only put four sheets on the reel. I've read too many opinions about 6 sheets occasionally causing problems. I'd rather not find out the hard way that they're right.

[tgtaylor]

I just tried the 2820 Test Drum with the 2509 reel. I DID have the center column. The result was excellent. No mottling, even development. I only put four sheets on the reel. I've read too many opinions about 6 sheets occasionally causing problems. I'd rather not find out the hard way that they're right.

Well they are not right. It's just a myth perpetuated by people who probably haven't figured out the correct way of loading the reel. If you spend a few minutes in daylight with a practice sheet you will see exactly how each sheet is to be inserted in its slot and the structures Jobo placed on the reel so that you can determine in the dark with you fingers whether or not each sheet is, in fact, inserted correctly. The only other "occasional" problem that you would have with developing 6 sheets is if you used an insufficient volume of developer.

Thomas

[Jehu]

Well they are not right. It's just a myth perpetuated by people who probably haven't figured out the correct way of loading the reel. If you spend a few minutes in daylight with a practice sheet you will see exactly how each sheet is to be inserted in its slot and the structures Jobo placed on the reel so that you can determine in the dark with you fingers whether or not each sheet is, in fact, inserted correctly. The only other "occasional" problem that you would have with developing 6 sheets is if you used an insufficient volume of developer.

Thomas

That sounds like a voice of experience. I spent at least 20 practice rounds on loading 6 sheets per reel in the daylight. It seemed okay to me. I was confident until I read too many accounts of sheets touching. One thing I do every time (4 sheets or 6) is feel the ends of the sheets to make sure that they're spaced about right. I'll probably give it a try with 6 next time. Thanks for that.

[Ari]

I usually develop 12 sheets at a time in a 2551 tank, and never once had a problem.
Go ahead, load up the reels; you probably paid good money for them, you might as well use them as they were intended.

[Cor]

There are 2 types of 2509 reels out, the older version (without "wings") can have problems with 6 sheets (especially thinner film stock), and is recommended for 4 sheets only.

The newer version 2509n has 2 black plastic wings which snap in place after loading 6 sheets. The sheets are further secured by these wings.

FYI I consistently have problems at the edge of PyrocatHD processed negatives (MACO IR);kind of surge marks on the horizontal sides of the negatives, and at the end were the negatives are touched by plastic "thingies". Less obvious or absent on XTol processed sheets (FP4). Currently testing a 3010 drum on a roller base.

Best,

Cor

[Ari]

I have the older 2509 reels, no wings, and load every reel with 6 sheets; never had a problem.
Maybe your agitation is too strong?

[Cor]

I have the older 2509 reels, no wings, and load every reel with 6 sheets; never had a problem.
Maybe your agitation is too strong?

Don't know, I have an older CPE2 which has 2 speed settings, I always use the lower setting (35 rpm) for PyrocatHD. In the older reel I processed 4 sheets max, I read somewhere that if you load 6 sheets of thinner more flexible stock the innermost film could flex/bulge and hit another sheet causing trouble.

Apparently your film is not flexing and causing trouble.

Best,

Cor

[tgtaylor]

I have the newer reels - the 2509N with the wings - but I really don't think the wings keep the sheets from coming out of their slots. Once the sheet is placed in a slot, the instructions say to give it a slight forward and then backwards tug and if inserted correctly it will not allow you to pull the sheet back out. In other words you can fell that it's locked in place in the slot and can't come out on its own. You'll also notice this with the wings off when unloading the reel.

Another thing, there's a a sharp and pointed structure on the inside of the reel. When loading in the dark I check and see that there is space between that structure and the first sheet (assuming loading from inside to out) and help each sheet out by giving the leading edge a slight bend with my thumb during insertion. The second sheet should be flush up against the structure on the inside and the 3d sheet flush with the outside end of the reel. If all three sheets are loaded correctly you can feel the even spacing between them with a fingertip.

Thomas

[europanorama]

i developped all my 70mm(220-172cm lenght) films in testtank 2820 and CPA2. b+w, E6(some), mostly CN C41 using offical 2517 reels. i tried to mount special 1 1/2 reel-method(one complete 2500 reel and one part of second one) to load 70mm. it should work. never tried with chemicals. tank seems safe.
testtank is base of 2840 without label.