I would Like to thank everyone for their responses to my earlier posting including Kodak, who have advised me that this problem only exists / existed in the 1 litre packaging. Thinking back about my experiences with the failures, I can't dispute this - nor can I confirm it. If so it solves a lot of problems for me.

Anyway, I would like to share a couple of other observations - things that I think I've noticed. First. Xtol is sensitive to agitation. I never had a problem with uneven development until I began to use Xtol. It required me to change my technique and pay a little more attention. Easly to solve, but you have to be careful. Second. The developed film takes on a slight brown cast. It doesn't appear to be neutral grey like in HC-110 or ID-11. Not a problem - just an observation. Last. Film base + fog is increased. There is noticeable density in the film edges. Sometimes it's a little distracting but easily printed through. Since my last failure, I have used ID-11. The results are so reliable and the film looks so good, that I'm almost reluctant to give Xtol another try. The problem is that when it works, it can work beautifully. I'd welcome any discussion on my observations.

-- Bill Lester (wlester@lesterconstruction.com), February 23, 2001

Answers

The 'Dreaded Xtol Failure" happens with one or 5 litre packs, with tap water or distilled water and with stock or diluted developer.

It has happened to a number of careful darkroom workers in varying locations.

It is unexpected and sudden, showing up with a batch of fresh developer as well as with developer that developed film the day before.

All my developer is used one shot and dumped, stock or diluted does not matter. Xtol has proven to be unreliable and I can't use it even though when it works (most of the time) it is very nice. How do you explain to someone that their film was 'lost' due to the developer not working right? Or, come home from two weeks shooting only to have a batch of film with no image on it? (while the same image from the other side of the film holder does just fine developed in ID11 or Rodinol).

Until The Yellow Peril gets their act together, Xtol is not used in my darkroom.

-- Dan Smith (shooter@brigham.net), February 23, 2001.

I'm convinced there's something different about peoples water, air, technique, or *something*, that would explain this. I just mixed up a fresh batch of 1L XTOL last night and will do some film today. I hope I'm not jinxing myself, but I've never had an XTOL failure since the stuff was introduced. One note. I'm fussy about having every speck of part A disolved before adding part B. This takes time and effort. Last night I put the mixing jug on a magnetic stirrer. It took more than a half an hour of mixing (85 deg to start) before every tiny particle of part A was dissolved. When I was doing it by hand, I'd mash the particles with the stirring rod and keep mixing. We're not talking caked powder here, just the normal process of getting the stuff dissolved. 99% of it goes quickly, but the last few grains are quite stubborn. The stuff normally works just super for me and I'll report back later with how this batch went.

-- Conrad Hoffman (choffman@rpa.net), February 24, 2001.

to those who have never experienced this failure, I am sure you suspect process problems. I believe most of us are reacting to developing not only hundreds of rolls of film in Xtol, but also to the history of developing films in other developers. if these problems occurred with other chemistry, we would certainly moderate our carpings.

I am a process freak, and have had failures from the same stock solution, same film, same day. it is much like an activation threshold must be crossed, and through a combination of contributors, it either is or isn't. if not, the reaction is somehow quenched and unable to sustain itself.

using Xtol yields much the same feeling and confidence, as using a rented Hasselblad lens that you know has a sticky shutter. once every hundred exposures, it will stick closed.

-- daniel taylor (lightsmythe@agalis.net), February 24, 2001.

Geez you all are making me nervous about my tank line (Xtol) here in my home darkroom. I've been running a small tank line (1 gal. tanks with floating lids) for about 2 years now. I change out the stop/fix/ perma wash monthly, but I've only started completely fresh twice. I'm a low volume user, so I aggressively replenish, and probably turn the tank over every other month or so. This way, I don't have to preseason the dev. I was using TMAX RS, but I read an article about Xtol, where they were basically saying Kodak had developed it as a long life deep tank dev. So, I thought I'd give it a shot. Kodak has alot of info. on their site about Xtol in deep tanks. You can get aim points for specific gravity, all that process control stuff. I've found it to be a great developer for trad. films, but have less success with TMX in 4x5, so I still have to default to TMAX RS for that. I use the 5 l packs for the repl. & keep it in a spigot tank with a floating lid. I have encountered the caking problem, but only in the smaller packs. The only thing I really don't like about it, is the fine dust involved with mixing it up. I have to immerse the bags in the water, and just be careful. If I get excessive buildup in the tank, I just filter this out. Except for the problems with TMX, I've found this to be a reliable dev. But then, I'm using it in a straight stock solution, not diluted as you all are. It's just been the cleanest, longest lasting tank dev. I've ever used.

-- DK Thompson (kthompson@moh.dcr.state.nc.us), February 24, 2001.

Luckily, I have never had the all to common Xtol failure problem. But I have had another problem you folks might know something about. When I process TMax 100 (TMX) 120 in Xtol undiluted, I have a problem with extremely small black specks on both sides of the film. I don't have the problem if the TMX is developed in other developers, and I don't have the problem with other films in Xtol. This definitely is not a problem with dust in the air or particles in the water. The Xtol is mixed using distilled water. PEC12 usually removes the specks, but occassionally one of the specks will be embedded in the emulsion and will be unremovable. Has anyone else had this same problem?

-- Ken Burns (kenburns@twave.net), February 24, 2001.

Well, another batch went just fine. Some HP5+ at 1:3 and a couple rolls of FP4+ at 1:1. It is sensitive to agitation as I added just one more twist per minute and could see a noticable density increase compared to what I usually get. Don't know if other developers would react the same or not. Dan- I'm not suggesting any sort of error or sloppy technique, just that there has to be some factor that can eventually be identified that causes the failure. The failures may appear random, but they still have a definite cause. Note that the cause doesn't have to be the developer. There could be a variable in the film that causes failure with XTOL but isn't detectable in other developers. Probably unlikely, but it pays to consider everything until enough clues develop to narrow the search!

-- Conrad Hoffman (choffman@rpa.net), February 25, 2001.

Conrad, I don't know if you're interested in any of this, but if you view the tech. data on the Kodak site, they have some pretty extensive tips about mixing Xtol. It almost reminds me of mixing up E6, the way they describe it. In addition to being sensitive to hard water, they give you the aim points for what the specific gravity, and the pH of a "correctly" mixed up stock (straight working) soln. of Xtol should be. Now, I haven't done any of this with my tank line, but I haven't had any problems either. The reason why I don't run TMX through this is that I am very used to the way TMX responds to TMax RS (it's what we run where I work), so when I ran it through my Xtol line, the results were a little different, and I like to be able to use developers I can predict. Which is not to say that Xtol won't work, it's just I like TMAX RS alot. Now, when I mix up E6, I worry about pH, specific gravity and water quality alot. If you look at the specs. for other developers like D76, T Max, etc. Kodak mentions nothing about this stuff up front. Now, it could be that in a process control manual, they have this info., but not on the general tech. sheet. What does any of this mean? I don't know, I'm not a chemist, but there has to be a reason why they list it there.

Ken, I have never seen that. Isn't PEC-12 usually used for non-water soluable marks? I was going to suggest that maybe you were picking it up in your wash water (or any other step), but since it sounds like it only happens with TMX in Xtol, I'm stumped.

-- DK Thompson (kthompson@moh.dcr.state.nc.us), February 26, 2001.

DK- Cool, I just checked it out. No, I never knew that Kodak published that data. OTOH, I've got lots of weird stuff, but I haven't got a PH tester. Do photo labs use test paper like litmus, or electronic PH meters? Or do they bother with PH at all?

-- Conrad Hoffman (choffman@rpa.net), February 27, 2001.

Conrad, yeah I think they probably do. At least anyone running a large E6 tank line would be concerned with pH at some point, as well as spec. gravity. I have never done this for a b&w deep tank, I haven't run a b&w control strip here in at least 7 years...we do check the sp. gravity when we mix up our E6, though. Not all the time, but it is important to do everything the same way (with that proc.). As far as pH, we don't have a meter. But we do "tweak" the color biasing on the color dev., based on what our control strips say. For us, we usually have to add Sodium Hydroxide to the c.d. to adjust the pH. I think if you wanted to test the actual chemistry (i.e. mixed Xtol), you would need an electronic pH meter. I've got a book here that lists a model that's good for E6, it's a bit dated, but it's under $100. I'm sure you could pick one of these up from a science lab supplier. If you were just checking your water, you could probably use a tropical fish water test kit, to check for hardness, pH, stuff like that. If you wanted to check the sp. gravity, Kodak can probably tell you which hydrometer to use for that. They do have a process manual for b&w but it's not available online. (the E6 manual is pretty $$ too). They do, however, have a publication online (Pub. O-3) that's called "B&W Tips and Techniques for Darkroom Enthusiasts". There's alot of good info. in here regarding repl. developers, etc. It's interesting how they talk about adjusting dev. times in TMAX RS by tweaking the pH as well. Again, what does it all mean. You got me!? But, I think the message is that this stuff is sensitive to just how it is mixed up, if it's anything close to E6, it could be very finicky....

-- DK Thompson (kthompson@moh.dcr.state.nc.us), February 27, 2001.

XTOL is my favorite developer. It renders sharp, full toned 120 negatives diluted 1:2. I home-process conventional films such as FP- 4, Tri-X Pan, Verichrome, Plus-X and APX 100/400 diluted 1:1 - 1:3. Once, out of 70 developed rolls, I experienced thin negs. That film was Agfa 100 diluted 1:3 and had a slight tan cast. 35mm negs are sharp with low grain souped in XTOL 1:1. XTOL is environmentally friendly, boosts film speed by 1/2 stop, mixes at room temp, gives different looks with dilution, does not have abnormal fog, and lowers your health risk. XTOL may be sensitive to local water PH, (D-76 changes PH as it ages), may not work well on some films diluted over 1:1, and experienced packaging problems.

-- Richard Jepsen (richard.jepsen@tinker.af.mil), June 22, 2001.