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612tom
27-Oct-2010, 18:00
Hi

As you might have seen from some of my previous posts, I’ve been gradually gearing myself up to shoot 4x10. I sold my 4x5 camera and kit, replaced it with a 4x10 and after trying out some direct positive paper I eventually found some expired film (thanks Jon) to start some tests. See the photos attached, please excuse the boring subject matter – I refuse to shoot walls or grey cards :) – these are just low contrast test shots. Ignore the newton rings too – that’s another problem I have to try and fix.

I don’t have a darkroom but managed to find a Paterson orbital with the electric base. I’ve seen people doing four sheets of 4x5 or one of 8x10 so I arranged 2 of the pegs to fit 2 sheets of 4x10 in there neatly. The previous owner did the trick of scoring the base of the tray and adding globs of plastic to lift the film up and that seems to work. However the agitation seems to be very uneven.

The film was FP4+ rated at 125iso, developed in Ilfosol 3 at 20dec C diluted 1:14 for 6 minutes, less 10% for constant agitation = 5min 24 seconds approx.

The Paterson says just 55ml of solution to cover but I tried this with the lid off and it certainly didn’t look like it would get everything wet, so I used 150ml of solution (10ml dev to 140ml water).

It looks like there were waves or vortices in the tank during development as the hotspots are in the middle of the negs. Is this where the agitation (and therefore development) was most strong? Or have I got it the wrong way round and the development at the edges is more than in the centre.

Should I try using more solution next time? Or is the problem the fairly short development time – should I try a more dilute solution? 1:14 was already the weakest suggested – 1:9 was normal.

I’d like to get good results from the Orbital as I’m sure it’s capable. A Jobo drum for 4x10 would be pretty expensive – but I’d be back with perfect results like I was with 4x5.

Thanks in advance for any pointers…

Wayne Crider
27-Oct-2010, 19:28
Apparently the previous owner didn't like it either? I've got one myself and it now sits in a box. The way I used it was to fill it like a tank so everything was just covered. In the end I went back to deep tanks then trays, and thats how I develop now. You might try hand agitation with some different movements and I'd up the solution quantity. I like my film agitated in the solution.

cjbroadbent
27-Oct-2010, 23:33
Try a dilute developer like HC110 1:30. Use two plastic coffee cupfuls (125ml each). Develop twice because 125ml becomes exhausted. Agitate by hand the first minute. This works for me - but I do 18 minutes and go for bullet-proof negatives for Alt processes.

Pete Watkins
28-Oct-2010, 02:15
I have 4 Patterson Orbitals and swear by them. I use the electronic base but I do lift the tray off the base about once a minute and rock it back and forewards in both directions several times. I've cut the fins off all the tank lids. I use 300 ml of D-76H diluted 1-1. I develop Foma 100 & 200 (I've still got some in the freezer) for 8 1/2 minutes and I have no complaints. Small amounts of heavily diluted developer can get exhausted fairly quickly in my experience. I occasionally sucessfully develop other manufacturers film sucessfully as well.
Good luck,
Pete

bvstaples
28-Oct-2010, 11:47
Like Pete, I've come to love mine, but it took some work and understanding. First of all, use as much liquid as possible (250-300ml seems to do it). I found if I used less than 150 ml I got what I see in your negs, light development on the outer edges and a swirling towards the center of the neg. If you think about it, doubling the chemistry is cheap, especially compared to the value of your image. And I don't reuse chemistry (at least to me it seems like the cheap part of the equation).

I also removed the fins from the lids, they would leave voids on the negs.

The other thing I did was rewire my base. I got a base from England that was 220V. I replaced the motor with a 120V and reduced the speed via a rheostat. Slowing down the agitation really improved the eveness of development.

With a little tweaking, your Orbital can produce fine, repeatable results.

My dos centavos...


Brian

612tom
31-Oct-2010, 00:23
Thanks for all the suggestions. I tried 375mm of solution (the most I can get in there without it overflowing) and went for intermittent agitation like I used to do with roll films. Tray on the agitator for 10 seconds each minute. The rest of the time I let it stand flat on the table. FP4 at 100iso for 7 minutes in Ilfosol 3 1:14 seemed to work well, the agitation seems pretty even.

Interestingly, the lid of my Orbital tray doesnt have the fins - and there are no signs of anything being removed. Perhaps Paterson changed the design at some point?

Anyway - thanks for your help

mark e mark
31-Oct-2010, 05:28
I develop two 5x7 negs at a time in mine. First time I had uneven development, since then I do't. What do I do to get even development. First off, the orbital is standard (still has fins), but I have put silicon blobs on the base, and squashed them down when they were tacky so they are only ~1mm high. I use 300ml of solution (could get away with 250ml), as people have pointed out 55-150ml, does not do the job.

However, I have given up on the static base agitation, and do the agitation by hand (its very boring). I hold the orbital level and tilt it in a clockwise manner so the liquid goes to all four corners (just like the what the standard base does, but by hand it is a more violent agitation -and works). Sorry for the long winded reply.

Ramiro Elena
31-Oct-2010, 06:31
I use 200ml without problems. Continuous hand agitation in circles. 4x5 and 5x7.

jvuokko
9-Nov-2010, 15:06
I liked the orbital with motor quite much until I begun to get too visible uneveness.
I don't really know the reason. One think could be that my Orbital's motorized base doesn't always rotate the tank (usually the tank rotates and does tilting movement). But sometimes it just stuck there and only agitation is tilting.

I have two Orbital tanks and one of them is more prone to getting stuck.


Dumped whole Orbital for a while until lately I have found that it works well when I use manual agitation in water bath.

My agitation pattern is to raise each side for two full cycles (left, farthest, right, nearest, left, farthest, right, nearest) once per each minute.

With manual agitation, the curved shape of the tank is bit of a problem, but using at least 300ml of developer it seems to work fine.

I hope that I tamed the Orbital at last.