JOBO Expert drum question

[Jim Graves]

Can the Jobo 3005 ... that is for 8x10 and 5x7 ... also process whole plate and 4x5?

I shoot 4x5, 5x7, and 6 1/2 x 8 1/2 (whole plate.) I realize I might use more chemical but I'm having a hard enough time paying $300+ dollars for a plastic container (3005) without having to spend another $280+ just to do my 4x5s (3006.)

Rhetorical question ... can't someone else start making these ridiculously simple drums and bring their cost out of the stratosphere?????? Jobo should be ashamed to charge what they do for these.

[Paul Ewins]

Short answer - Yes

Long answer - You may use more chemicals as the 3005 is twice the volume of a 3010. This may not be an issue depending on how many sheets you put in and whether you use a dilute developer. I normally use ID11 @ 1:1 as a one shot and the volumes given by Jobo work just fine for this.

Although a 3005 should theoretically hold 20 sheets of 4x5 I would be worried about them overlapping and scratching. By putting them in sideways you should get 2 per tube (i.e. 10 total) and they should curve nicely against the walls. At this point you have half the usual amount of film in the drum but still require the same minimum amounts of chemistry to make sure the film is covered. So maybe going to 1:3 dilution would give you enough volume to cover the film without having excess chemistry go to waste.

I don't know whether you can simply dilute C41 or E6 to suit the volume requirements and it is important to note that the minimum volume requirements for E6 and C41 are different to the standards for monochrome developers.

5x7 and whole plate will be a whole lot less fiddly than 4x5 and if you put the 5x7 in sideways you should be able to get 10 sheets of that in too, which is a step up from the 6 sheets in a 3006. The one caveat is that the individual cylinders in the Jobo drums are designed with a slight outwards bow, like a corinthian column, and this might mean that the chemical doesn't circulate around the back of the sheets the way it should. I would certainly try it and see before buying another drum for the smaller formats.

hope that helps,

Paul

[Chuck Pere]

I think that those curved cylinders are the reason for the high cost. I've done 4x5 a couple times in a 3005. No obvious problems but I've never checked it out with a large area of continuous tone.

[Michael Alpert]

if you put the 5x7 in sideways you should be able to get 10 sheets of that in too, which is a step up from the 6 sheets in a 3006.

In my experience, sheet film moves around quite a bit in Jobo drums, so I would not put 10 sheets of 5x7 film in a 3005 drum. I have found that the Jobo instruction manual is accurate. If you follow Jobo's advice, you'll be fine.

[Jim Noel]

The inner tubes are not cylinders but barrels. They are larger in diameter in the middle than at the ends. Thus film moves around, usually toward the center making more than one sheet in a tube highly questionable.

[Jim Graves]

UPDATE: I bit the bullet ... bought a Jobo 3005 ... omigod! ... this thing is HUGE ... I had no idea how big it was ... I have it sitting upright next to my recliner ... it looks like a floor lamp base. I take back everything I said about it being over-priced.

I've been using Beseler drums doing two negatives at a time on a Beseler rotating base ... I thought the larger Besler drums were big ... no comparison.

Now, I just have to see what it does with my whole plate negatives. I just hope the Beseler base will turn this monster without bursting into flames.

[Vaughn]

LOL! So far no smoke or flames coming out of my motor base yet -- though my 3005 drum tries to take a hike off to the right on the Unicolor base. I just stick something for it to run into. The motor base does sound like it is working hard when I put a liter of chemicals in it...I hav e a Beseler base as an eventual back-up if the Unicolor goes on strike.

I have not used mine yet for 5x7 -- but will eventually (I just bought 200 sheets of TMX).

Vaughn

[BarryS]

If my corroding Chromega roller can handle the 3005, I'm sure your Beseler base will do fine. I was actually expecting the drum to be bigger considering it holds 5 sheets of 8x10 film. Considering most darkroom gear is free to cheap these days, the Expert drums are painfully expensive, but they're a complete joy to use, and economical with developer use. I'd love to have a version that takes 10 sheets of 8x10 film because I usually shoot 6-8 sheets when I go out.

[R Mann]

These look interesting for doing a few sheets at a time. I have no experience using a Jobo Expert Drum - but do have a couple of questions. If you had the minimum equipment - just the drum and a set of rollers could someone explain?

1. How many revolutions per minute do they need to be turned? Do you change direction? How often? Is this important to control, or does it just need to be random?

2. How do you put the chemistry in the drum? How do you drain them? Do you need funnels, or tubing?

Thanks-

[BradS]

I use the 3006 on a Beseler motorized roller base. I think that the 3006 is a little smaller than the 3005 but, not much. My roller base does not reverse directions and I really do not see the need. The flow of liquids inside the expert drums has got to be very chaotic. If you've ever seen the "tubes within" concept, I think you'll understand. Some people use a funnel. I don't. I've found that by simply tilting the drum slightly, the chemistry can be poured in directly. Do not try to set the drum up right and pour stuff straight in...you'll have and instant mess.

How many rev's per minute? I don't know. It seems like twenty or thirty....Whatever the roller base does. It's not that fast really.

I'm sure others will demand that the drum be picked up and turned around every minute while it is on the roller base. I have not ever noticed any need for this extra effort with the Expert drums. So too, others will insist that you must have a curved funnel...it would be nice but doesn't seem necessary. The foot pump thing would also be nice but, I don't have one aand have been able to manage without.