Very thin negatives with MYTOL

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mjbovee

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I mixed a batch of mytol last night and got some really thin negs using the suggested dev time starting point for XTOL from the HP5 data sheet. I think I have an idea of where I went wrong

I used the following formula:
85g sodium sulfite
4g sodium metaborate
12g sodium ascorbate*
0.15g phenidone (from a 0.2% solution I had mixed a few weeks prior)
3g sodium metaborate metabisulfite

but unfortunately I believe I used used ascorbic acid instead of sodium ascorbate. I think this lowered the pH of the developer below 8.2, however I don't have any way to confirm this at the moment. It wouldn't be a big deal to just toss the batch and mix up another, but I would like to save this one if possible. Does anyone have an idea of how I can boost the pH here? I'm assuming borax or sodium carbonate would do the trick, but I'm not sure what quantity would be needed.
 
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albada

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Yes, adding s. carbonate will boost the pH. But you'll need either a pH meter, or pH paper, or use trial-and-error (mostly error).
BTW, you listed sodium metaborate twice.

If you have ascorbic acid on-hand, you can use the following formula:
90g sodium sulfite​
4.1g sodium metaborate​
9g ascorbic acid​
0.15g phenidone​
I tested this formula with 0.2g dimezone-S instead of phenidone, and found it to be a promising clone of XTOL.

Mark Overton

Edit:
Perhaps you could mix a small amount of the above formula, and see how long it takes to develop a bit of leader to be dark (when viewing a light through it).
Then add carbonate to your batch of Mytol, and measure the time to reach the same darkness. Keeping adding carbonate until the time is the same. OR, multiply dev-time by the ratio of those two times.
 

koraks

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Does anyone have an idea of how I can boost the pH here?

Adding any of the common alkaline chemicals will do. I usually use sodium hydroxide (e.g. a 1% or 10% solution) and a dropper. In your case, the more mild sodium carbonate would do nicely as well.

I've posted in the past a formula for instant mytol that uses ascorbic acid and borax instead of ascorbate and metaborate; you should be able to find it fairly easily using Google. It works very well with HP5+, giving sufficiently dense and fine-grained negatives with ease.
 
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mjbovee

mjbovee

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Yes, adding s. carbonate will boost the pH. But you'll need either a pH meter, or pH paper, or use trial-and-error (mostly error).
BTW, you listed sodium metaborate twice.

If you have ascorbic acid on-hand, you can use the following formula:
90g sodium sulfite​
4.1g sodium metaborate​
9g ascorbic acid​
0.15g phenidone​
I tested this formula with 0.2g dimezone-S instead of phenidone, and found it to be a promising clone of XTOL.

Mark Overton

Edit:
Perhaps you could mix a small amount of the above formula, and see how long it takes to develop a bit of leader to be dark (when viewing a light through it).
Then add carbonate to your batch of Mytol, and measure the time to reach the same darkness. Keeping adding carbonate until the time is the same. OR, multiply dev-time by the ratio of those two times.

Great suggestions, thanks. Yeah, I meant to say 4g sodium metaborate and 3g sodium metabisulfite. I'll give your formula a try
 
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mjbovee

mjbovee

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Adding any of the common alkaline chemicals will do. I usually use sodium hydroxide (e.g. a 1% or 10% solution) and a dropper. In your case, the more mild sodium carbonate would do nicely as well.

I've posted in the past a formula for instant mytol that uses ascorbic acid and borax instead of ascorbate and metaborate; you should be able to find it fairly easily using Google. It works very well with HP5+, giving sufficiently dense and fine-grained negatives with ease.

Cool, is this it? https://www.photrio.com/forum/threads/film-developer-with-out-hydroquinone.189624/post-2514181
 

MattKing

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That's the one. Sorry for the late response. Looks like the new forum software messes up the table layout....

Thanks. I've sent a report about tables to Sean.
 

john_s

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.....
0.15g phenidone (from a 0.2% solution I had mixed a few weeks prior)

I had an experience when a phenidone stock solution deteriorated quite fast. It was in alcohol but there was some water content, and that is, by all accounts, not good.

What was your phenidone dissolved in?
 

Down Under

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Who knows why this went wrong?? Old chemicals, the wrong mix, incorrect process times, iffy temperature, or just a bad day overall. We have all done this before. I surely have.

Sodium hydroxide could be your culprit. In my experience it can be "iffy" to work with. Did you buy it from a photo supply shop or did you use the supermarket brand (usually sold as toilet cleaner/drains unblocked)?? The latter may have additives not really compatible with film emulsions.

As for Phenidone, in my experience it is best mixed up immediately before you brew your developer, not kept in an alcohol solution. Mixed chemistry stored too long does deteriorate. Ask me, I know...

The same with using household borax in place of sodium metaborate. I lalso earned this one from one bitter experience.

For all this doom and gloom, don't give up on Mytol. If you tend to use the same film/s, I suggest you do a test roll at box speed, then down three and up two ISO settings. Ideally, do an entire roll if you can, as this will give you several segments of film to experiment with. Process one "cutting" normally, one 20% longer and one 20% lesser. Keep notes. With this method you will soon work out your best times overall for both your exposures and processing.

The positive outlook is, with careful scanning, your "thin" negatives may produce surprising results. I recently had this disaster with two rolls of long-outdated Kodak Panatomic-X I processed in some home brewed (I can't remember which, probably Agfa Ansco borax MQ) and got undeveloped negatives. the scans took more time than usual, but produced some lovely dark shadows with surprising detail. Try it and see.
 

MattKing

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koraks

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Ozmoose, for what it's worth, I've never had any issues with drain cleaner hydroxide, borax from a brewer's supply store or phenidone solutions mixed in consumer grade glycol. In fact, I pretty much never use "photo grade" chemicals from "reputable" channels unless there's absolutely no other supplier to be found. I've yet to pay the price for this reckless attitude.
 
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mjbovee

mjbovee

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That's the one. Sorry for the late response. Looks like the new forum software messes up the table layout....

No problem. Tried out your formula last night and got great results, even with a 2 stop push.
 

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