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View Full Version : Of Rotaries, XTOL Replenished, and Foam



m00dawg
4-Mar-2019, 07:29
Figured this might be a good place to ask since I'd imagine some fellow LF folks might be using XTOL replenished since dev'ing sheets can require a lot of chemicals. In fact that's the very reason I started down the path of using XTOL-R. The problem I'm having is I'm getting foam which I haven't quite figured out how to mitigate/remove so I can pour most of the solution back into my replenishment bottle. It wasn't as much of an issue when using an accordion bottle but is a problem with glass.

I went with a glass bottle since it has a narrow neck to make pouring easier and also I don't have to fiddle as much with the accordion. Instead my plan was to just put in my 75ml of stock then top it off with the used developer all the way up to the top to avoid an air gap. Trouble is, because of that foam, I'm left with foam at the top. It settles down after about 24 hours but then to fully remove the air gap I have to go back and add a tiny bit more developer.

I tried using my funnels that have a screen on the bottom, but the bubbles seem to either go right through or get created by pouring the dev in. I thought about maybe using a coffee filter but wasn't sure if that was pulling out any chemicals I want in the solution?

I suspect this would be less of a problem with hand inversions over rotary processing which I'm now doing. I know I can hand process with a 2500 but my rotary setup along with XTOL-R has been pretty consistent and it also lets me be a little lazy :P

Long story short, anyone have suggestions on how to tame XTOL foam?

koraks
4-Mar-2019, 07:41
If you poor developer in until the bottle is full, the foam siply overflows, no? That's what I do with RA4 developer which I replenish and which also foams like crazy.

m00dawg
4-Mar-2019, 08:16
If you poor developer in until the bottle is full, the foam siply overflows, no? That's what I do with RA4 developer which I replenish and which also foams like crazy.

I thought about that, but then the foam gets everywhere haha and I have to worry about cleaning it up. Hmm I suppose I could put the glass jar in the sink if it'll sit flat then wipe it down. I was thinking of maybe trying to skim the foam off the developer in the beaker somehow before I pour it back in.

pau3
4-Mar-2019, 08:54
Are you getting foam with all your films or only for some specific brands? In any case, a thorough pre-rinse may help to get rid
of any wetting agents the films may have incorporated in their emulsions. Try to perform it in two steps: pre-rinse, dump the water, pre-rinse again.

m00dawg
4-Mar-2019, 09:02
Hmm that's a good point.

All my films, in varying degrees cause it. It seems to be worse with sheet films than roll films. I'm guessing the end wings on the 2500 spool contribute to more agitation there perhaps. I feel like my XTOL is foaming more than it did though I haven't changed anything. Thinking it has to do with it starting to become seasoned.

I used to be huge into pre-rinsing but I recall reading, I think in Ilford docs, NOT to pre-rinse when using a rotary though it didn't say why. In hand tanks I always pre-rinsed. Seems like that's better for the developer as well since it doesn't pick up those wetting agents or anti-halation layers.

EDIT: After reading through this (https://www.largeformatphotography.info/forum/showthread.php?46017-no-pre-soak-for-Ilford-films) post about pre-soaking I think I might go ahead and give it a go. I haven't had any unevenness by not pre-soaking for any films _except_ a few sheets from the new CHS ii which had uneven development. They had a line where the developer was sitting in the tank while I was pouring it in before I put it on the rotary (wasn't but a few seconds). Pouring the dev out of the tank after CHS ii has a bright yellow color, almost the color of Ilford stop bath. I assume that is the anti-halation layer but maybe pre-soaking may help with it.

Worth a shot anyway if it will help with the foam.

koraks
5-Mar-2019, 01:26
Do you use wetting agent in your tank? Do you thoroughly rinse the tank after use? Maybe it's just carryover from the previously processed roll.

And yes, I pour back the developer over the sink so the foam can easily be washed away. Rinse the outside of the bottle after capping it and dry it with a towel.

Pere Casals
5-Mar-2019, 02:23
Long story short, anyone have suggestions on how to tame XTOL foam?

I'd use a LIQUID FOOD GRADE DEFOAMER

188447

This is silicone based so mostly inert, it is used at very, very low concentrations (2 ppm, parts per million, 0.002ml per 1L, buy the smallest possible bottle) with impressive effects. Check that it has no interference with development, buy I guess it won't, at all. Disolve 1ml in 1L for the intermediate dilution, then add 2ml of the dilution per 1L of developer.

These additives are used in many situations, from burger fries (to remove oil foam) to Spa resorts.

I use that proffesionally.

Silicone is dimethylpolysiloxane, it looks McDonald's uses it in some countries

https://yourquestions.mcdonalds.ca/answer/why-do-you-use-dimethylpolysiloxane-in-your-fries-its-also-an-ingredient-in-silicon-caulk-and-hair-conditioner-/
https://web.archive.org/web/20190305092826/https://yourquestions.mcdonalds.ca/answer/why-do-you-use-dimethylpolysiloxane-in-your-fries-its-also-an-ingredient-in-silicon-caulk-and-hair-conditioner-/

____________________


Anyway as you use a rotary I'd use regular Xtol one shot, you won't have much waste.

Rotary mixes a lot of air in the chem, this is not good to keep the used developer, anyway using a defoamer may be good to avoid problems.

m00dawg
5-Mar-2019, 07:47
Thanks Koraks, Pere!

Nope I don't use a wetting agent in the JOBO 2500 itself. Instead I use a Patterson tank for that. For sheets I take them off the 2500 spool one at a time and give them a dunk and let them sit for a few seconds, then put them on my drying rack. For roll film I make a U shape and sort of seesaw the film in the Pattrson tank a few times. Slightly more work than just using a wetting agent directly but since the JOBO tank and reels cost so much more than Patterson tanks, I decided it was worth following their advice just in case. On the plus I tend to reuse Photo-Flo a few times this way which saves on distilled water (it's not expensive here or anything but it means I can buy less and have to lug around less).

Good call on the anti-bubble stuff, Pere, I'll look into that! Yep I could just go back to 1:1 now that I'm solidly able to use a rotary but I've already gone down this XTOL-R path so far it's hard to turn around :P XTOL 1:1, or another devleoper, would help for when it tends to get warm here as I dev up around 24C in the summer and that makes some films (notably CHS ii) dev fast using XTOL stock or replenishment. Even in the winter I tend to be around 22-23C if I don't use an ice bath (and I've tried to avoid that so I can keep my wash water, which comes from the tap, close to the dev temps).

Foam aside, I feel like I've got my times down pretty well with my replenished solution and it does produce nice grain and seems to have a nice buffer in terms of XTOL falling off since it's a bit stronger and I can use more developer than the bare minimum in a tank for more safety margin. I can also combat the oxidation by way of the rotary by adding more stock back in. Kodak says 70ml and I've read some folks using 80, but so far 75 has worked for me. I do need to get test strips though (I "test" using FP4 bulk rolled film). I've done about 30 equivalent rolls of film with it so I think it's getting close to be fully seasoned but not quite there yet.

I dunno if I'm seeing the supposed amazing results using replenishment over 1:1 (folks on a certain other forum waxed poetic about grain) but it's been a fun experiment and does give nice results. I pushed HP5 to 1600 in 35mm and the results were pretty great. All told XTOL-R has some pros and cons for sure.

Mark Crabtree
5-Mar-2019, 08:29
I like replenished Xtol and have used it for a number of years along with a couple other replenished developers. Be aware that you may need to increase your developing times as you continue to use the developer; that is normal, and will eventually stabilize. I particularly like this developer for Fuji x-ray film where times tend to be too short, and contrast too high, in other developers.

All of the replenished developers I use have the foaming, which I believe comes from wetting agents incorporated into many films to help with even development. That is one reason some manufacturers don't recommend pre-washing before development, but also just one more reason I do like to pre-wash; it keeps at least some of that from accumulating in the replenished developer. I just let the foam run over the top, then rinse the bottle. I top it up in a sink, but standing the bottle you are filling in a tray would work fine also.

m00dawg
5-Mar-2019, 08:40
Oooh a tray is a good idea. I think my bottle is slightly too large to do that easily in my current setup but I think that's a good call. Maybe I can do a bit of rearranging.

Yeah to pre or not to pre, that is one question. Never thought about it until foam but then I noticed some uneven development with some of my CHS ii sheets (so maybe they have no wetting agents?) I haven't been pre-washing since moving to rotary but I'm definitely pondering it now if it helps the foam issue though looks like I'll want to be a little faster with pouring the dev in and getting the tank on the rotary at least when using sheets.

Times wise, indeed I'm hoping and expect they will go up a bit. I've started with XTOL stock times but using a rotary which seems to have balanced things out so far - I get the density I'm looking for with most films. Pancro 400 has been elusive to figure out but CHS ii only took a few go arounds (6:30 at 23C looks to be just about perfect). I've been tracking all this via a web app I wrote. That way I can look at the data using various tools if I need to (graphing dev times over a particular film, for instance, or how much solution I've replenished over what I started with, stuff like that) so if I need to increase times I can make an informed decision hopefully.

Do you use test strips? If so where does one find these?