beginner - 24 exp. vs 36 exp in diluted xtol

LarryP · Dec 3, 2011

I know it's a really stupid question that am 99 % sure i know the answer to. I am going to start developing at home Foma and fuji across in diluted xtol probably either 1: or 1:3. I'm aware of the 100 ml minimum of xtol. My question is do I need to adjust time or anything if I'm developing a 24 exposure roll versus a 36 exposure roll? I'm all excited about getting started with this. When She Who Must Be Obeyed saw the cost savings she allowed that Santa would likely bring what I need. I just can't F up the spare bathroom when I develop there

Jeff Kubach · Dec 3, 2011

You don't have to adjust the time, it is the same. I pefer the shorter rolls. I use my RB67 with the 120 backs which only have 10 expourses.

Jeff

foc · Dec 3, 2011

When developing B&W 35mm films it doesn't matter if they are 24 or 36 exp. If you developing tank says 300ml for 1 film then you use 150ml of water and 150ml of Xtol (1+1) or 200ml of water and 100ml of Xtol (1+3).

Since you are using the developer as a one shot (use once and throw away) then it doesn't matter if the film is 24 or 36 exp, it's the amount of solution needed to cover the film dev spool that matters.

Some dev tanks allow two 35mm films to be developed at the same time but make sure that both films have the same developing time in Xtol, otherwise develope them seperately.

LarryP · Dec 3, 2011

Thanks Jeff, figured no adjustments were needed but just wanted to make sure. I have been known to overthink things. What got me thinking was the fact the shorter rolls are only 2/3 the surface area.I'll be doing some 120 as well found a pentax 645 in my price range a couple months back,well it was my early birthday and Christmas present. I was lucky to survive that deal as it was done without consultation a pristine body with cap, strap and large eyecup for $100.

Roger Cole · Dec 3, 2011

The time needs no adjustment. IF you are using more solution than needed to cover the film in order to get the minimum amount of stock developer needed per roll, then you may be able to use 2/3s as much stock for the shorter rolls, provided there is still enough diluted developer to cover the film. Personally, developer is cheap, and Xtol only comes in those horrible 5L sizes anyway, so I'd just use the full amount.

I prefer shorter rolls too. I load 24 from bulk rolls. When I buy commercial loads though I most often go ahead and get 36s because the cost per frame is lower than 24, even if I stop the roll short of using all 36.

Sirius Glass · Dec 3, 2011

LarryP said:
When She Who Must Be Obeyed ...

Words of Wisdom #1:
After serving for 24 years, I declared myself a free agent.
I got the two children; she got my dog.
Now I no longer have a Higher Power.
The new models have more features, have much lower mileage and are virtually maintenance free.
Life is good!

Words of Wisdom #2:
XTOL replenished not only lasts longer than diluted XTOL, but also it produces a smoother range of tones, and it is cheaper per processed rolls of film.

Steve

Gerald C Koch · Dec 3, 2011

Kodak no longer recomends any Xtol dilution greater than 1:1. Follow their advice.

eddie · Dec 3, 2011

If you're using stainless reels, you may find the shorter length a bit easier to load.

Roger Cole · Dec 3, 2011

Gerald C Koch said:
Kodak no longer recomends any Xtol dilution greater than 1:1. Follow their advice.

Why? Is this a general "follow the instructions" rule of thumb (in which case I heartily don't agree, though agree it's usually a good place to start) or based on some negative experience with Xtol diluted more than 1+1?

eddie · Dec 3, 2011

While replenishment isn't difficult, the OP is just beginning to process his film. As such, I think replenishment just adds another variable, when he should be honing his technique and results.

MattKing · Dec 3, 2011

The shorter rolls are less likely to run up against the capacity limits - if 100ml of stock is minimum for 36 exposure, then 75ml is probably fine for 24 exposure (the ratio isn't strictly linear, because while the exposed frames have 2/3 the area, the leaders are the same).

This means that if you are trying to use 1 + 2, you will be able to fit it into a 250 ml tank (75ml + 150 ml = 225 ml, whereas 100 ml + 200 ml = 300 ml).

And Jeff, the 120 roll in your RB67 requires the same developer as a 36 exposure roll of 135. Whether you are shooting with a 6 x 4.5 back, 6 x 7 back or 6 x 8 back, it is the same amount of film .

Sirius Glass · Dec 3, 2011

Michael R 1974 said:
Roger, there were connections made between the "XTOL failure syndrome" and dilutions greater than 1+1, particularly when using tap water which can be significantly aerated. It has never been clear to me if that was Kodak work or just people grasping at straws. Based on everything I've read on the subject that problem had much more to do with the packaging for 1L (which is why you can only buy 5L packets now). My guess is Kodak would prefer you stick with stronger dilutions so that you use more developer . Personally I've never had a problem with 1+3. Just make sure you use a decent total volume.

I have not seen a linkage between XTOL failure syndrome and dilutions greater than 1+1. The former was a packaging problem which was taken care of years ago. The later Kodak advises against, yet some swear by it. I do not have enough experience with diluting developers but I have always used developers full strength or replenished.

Roger Cole · Dec 3, 2011

Yeah, I agree it shouldn't have anything to do with dilution. I hated Xtol for years after it came out because I bought some 1L packs and got think almost blank negatives, using 1+1. I tried more than one pack and mixed it with distilled water so I just concluded (even though I had heard of it being bad) that Xtol sucked, at least for me. I tried it again years later and it worked fine, but I don't really want to mix 5L of developer from powder.

The formula, or something very close to it, is pretty much an open secret and at least one company makes what they say is an "equivalent" developer - but they only sell it in 5L packs too. Someone should package it in something smaller.

I've never replenished developer. My darkroom usage is spastic and unpredictable with my schedule, so for me diluted one shot is a much better idea (except for Diafine which I do use and which just keeps working and working.)

ulysses · Dec 3, 2011

foc said:
When developing B&W 35mm films it doesn't matter if they are 24 or 36 exp. If you developing tank says 300ml for 1 film then you use 150ml of water and 150ml of Xtol (1+1) or 200ml of water and 100ml of Xtol (1+3).

1:3 is one part developer to 3 parts water. For 300 ml, you use 75 ml of developer and 225 ml of water for a 1:3 dilution, which some would claim is not enough volume of developer for a 36 exp roll. I make no such claim, just pointing out that some do, nor do I have an opinion on whether dilution of Xtol beyond 1:1 is a good or bad thing. I usually mix my own developers and have many opinions about them, but this probably isn't the place to air them.

Ulysses

LarryP · Dec 3, 2011

I really appreciate all the advice guys. Steve been there done that on declaring free agency. I may refer to her as she who must be obeyed or The Redhead From Hell but she is a keeper. I have considered replenished xtol and understand the benefits but as eddy pointed out I am just starting to do this and want to keep it as simple as I can at first. I'll probably give replenishing a try once I can get consistent results I like at a given dilution and time. I will be developing single rolls in a 2 roll tank with a total of 400 ml of solution and a second empty reel to take up the extra space.

Gerald C Koch · Dec 4, 2011

Roger Cole said:
Why? Is this a general "follow the instructions" rule of thumb (in which case I heartily don't agree, though agree it's usually a good place to start) or based on some negative experience with Xtol diluted more than 1+1?

Xtol now contains a chelating agent DTPA to prevent a particular form of oxidation which can cause the "sudden death syndrome." Remember when you dilute Xtol you are also reducing the amount of chelating agent. It may be that dilutions greater than 1+1 lower the effectiveness of the chelating agent thus hastening oxidation.

There is also a peculiarity about ascorbic acid as a developing agent. Remember it is used to replace hydroquinone. The oxidation product of hydroquinone (hydroquinone monosulfonate) is also a developing agent albeit weaker than the parent compound. Then too the oxidation of hydroquinone causes an increase on pH increasing the developer activity. However, the oxidation product of ascorbic acid has no action as a developer. In fact it actually inhibits development by lowering the pH. So there is a double whammy -- oxidation not only removes developong agent from the solution but it also lowers the pH resulting in less development. This difference in the chemistry of the two developing agents is one of the reasons why Xtol behaves differently from D-76 or such developers as Microphen.

A good source of information is at www.covingtoninnovations.com/xtol.

Jerry

Gerald C Koch · Dec 4, 2011

ulysses said:
1:3 is one part developer to 3 parts water.

To many people 1:3 means 1 part to make a total of 3 parts or 1+2. This why it is better to use the unambiguous notation using the plus sign '+' rather than the colon ':'.

Roger Cole · Dec 4, 2011

Gerald C Koch said:
Xtol now contains a chelating agent DTPA to prevent a particular form of oxidation which can cause the "sudden death syndrome." Remember when you dilute Xtol you are also reducing the amount of chelating agent. It may be that dilutions greater than 1+1 lower the effectiveness of the chelating agent thus hastening oxidation.

There is also a peculiarity about ascorbic acid as a developing agent. Remember it is used to replace hydroquinone. The oxidation product of hydroquinone (hydroquinone monosulfonate) is also a developing agent albeit weaker than the parent compound. Then too the oxidation of hydroquinone causes an increase on pH increasing the developer activity. However, the oxidation product of ascorbic acid has no action as a developer. In fact it actually inhibits development by lowering the pH. So there is a double whammy -- oxidation not only removes developong agent from the solution but it also lowers the pH resulting in less development. This difference in the chemistry of the two developing agents is one of the reasons why Xtol behaves differently from D-76 or such developers as Microphen.

A good source of information is at www.covingtoninnovations.com/xtol.

Jerry

Thanks. That would seem to make good sense as far as not over diluting the stock (in fact it makes me wonder if it could be UNDERDILUTED to good effect on longevity - dissolved in only as much water as it takes to fully dissolve the powder then diluted accordingly when used as a one shot working solution) but I wouldn't expect dilution for one shot use just prior to development would have any effect on oxidation, unless it oxidizes very, very quickly at that dilution or, probably more likely, it makes it more prone to exhaustion during development? But I'd think one could work around that by just using more solution, given sufficient agitation.

In any case I don't use it right now but I will keep this in mind if I try it again in the future.

Sirius Glass · Dec 4, 2011

Gerald C Koch said:
To many people 1:3 means 1 part to make a total of 3 parts or 1+2. This why it is better to use the unambiguous notation using the plus sign '+' rather than the colon ':'.

There is no logical reason to take the clear and direct annotation of 1:3 and obfuscating the meaning by using 1+2, unless the goal is to befuddle others out of pure meanness.
1:3 means 1 part to three parts and not 1 part into a total of three parts; "1:3 means 1 part to three parts" is used in chemistry books and cook books.

Roger Cole · Dec 4, 2011

Sirius Glass said:
There is no logical reason to take the clear and direct annotation of 1:3 and obfuscating the meaning by using 1+2, unless the goal is to befuddle others out of pure meanness.
1:3 means 1 part to three parts and not 1 part into a total of three parts; "1:3 means 1 part to three parts" is used in chemistry books and cook books.

Most chemists would disagree.

Granted in photography we have long used 1:3 to mean one part concentrate or stock to three parts water. But in chemistry, and thus to some coming to photography from other fields, it's confusing because it means exactly what the post you were responding to said (in fact I had started to point that out myself but every time I do, a weird argument ensues.)

I always prefer the 1+3 nonemnclature because it's clear and unmistakable to BOTH groups - people who only know darkroom work and those coming from other fields that involve mixing solutions.

EDIT: Or, I notice you say it means the same in chemistry. When I took high school chemistry in 1980 and college freshman chemistry a couple of years later 1:3 meant one part in a total of three parts. Maybe that convention has changed since. Never the less, no one mistakes 1+3 while some might mistake the meaning of 1:3.

2F/2F · Dec 4, 2011

Here we go again...

The ":" can be used to indicate either a ratio or a factor, depending on the commonly-accepted use in the particular field in question. You have dilution ratio (1:3 = 4 parts total) or dilution factor (1:3 = 3 parts total). Basically, only scientists use dilution factor. Pretty much all laymen (and photographers) use it to indicate a ratio; that is what ":" is commonly understood to be in "real world" use. So there should be no confusion in the matter...but if there is, a closer read of the manufacturer's technical data sheets and instructions will clear it up.

Roger Cole · Dec 4, 2011

You're right of course - but why not just write it as "1+3" and be done with it? Since NO ONE will misunderstand that?

2F/2F · Dec 5, 2011

I am more confused by the plus than by the ratio symbol, since I have never seen it used that way. Numbers separated by ":" clearly indicate that the numbers are meant only to indicate proportions (except in the aforementioned professions). Numbers separated by a "+" indicate that the numbers on either side are the actual amounts to be used in measurement. Anyone who has passed 1st grade math knows that. Using an addition sign to indicate a ratio, against common conventions, is not clear.

And neither of them mean anything without stating what the numbers on each side of the symbols mean. You don't just say "1:3," because it doesn't mean anything by itself. You'd say something along the lines of, "Stock to water 1:3," "One part water to three parts stock," both of which make it abundantly clear. If you say "to" or "ratio," it is immediately clear what is meant.

Roger Cole · Dec 5, 2011

Suit yourself. I've seen 1+3 in photography since at least the 1970s, to indicate one part stock PLUS three parts water. Makes perfect sense to me. We could just write "1 to 3".

Shrug.

Gerald C Koch · Dec 5, 2011

Older formulas would often say "dilute 1 part of developer with 3 parts of water." A bit wordy but totally unambiguous. The problem is that some mathematically challanged people do not see the ':' as indicating a ratio. People on APUG are fairly frequent in asking dilution problems. Let's make it easy for them. For this I personally prefer the '+' notation.

beginner - 24 exp. vs 36 exp in diluted xtol

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