Benzotriazole and Sodium Carbonate solutions

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Photopathe

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I have been trying to use Benzotriazole (1%) and Sodium Carbonate (10%) solutions as instructed in Steve Anchell's Darkroom Cookbook to increase contrast or revive aging developer but with no success so far. I do get slightly cooler tones when adding BZT but the effect is quite subtle and as for the rest I get the opposite results. The lighter tones get all washed out and I need to extend the developing times to try to reach the same black levels as I get without adding Carbonate and/or BZT. I taught maybe I was adding too much the first time as I read that this could produce these effects so in a second batch of developer I went progressively with minute amounts but to no avail. I am trying this with Ansco 130, home brewed based on the recipe give in the Darkroom Cookbook.
I would like to know if others had the same experience and if anyone has any advice.
Thanks!
 

pentaxuser

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Photopathe, there was an interesting thread on this on a site called FADU(Film and Darkroom User) It is a U.K. based site. It's free to join like Photrio but I am unsure whether the rules allow a new member to search the site before he/she is accepted as a fully fledged member which requires I think 5 posts but you can certainly ask about it in your first post

The thread there is called "Boosting dmax on not so new papers" Briefly the originator said that 7.5 grms of Sodium Carbonate per litre of developer worked best to increase the blacks but bear in mind this was in relation to ageing papers and not ageing developer as far as I can recall

pentaxuser
 

tezzasmall

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Photopathe, there was an interesting thread on this on a site called FADU(Film and Darkroom User) It is a U.K. based site.

The thread there is called "Boosting dmax on not so new papers" Briefly the originator said that 7.5 grms of Sodium Carbonate per litre of developer worked best to increase the blacks but bear in mind this was in relation to ageing papers and not ageing developer as far as I can recall

pentaxuser
Here is the link to the actual thread. It was easy to find as I was the originator of the thread. :D

http://www.film-and-darkroom-user.org.uk/forum/showthread.php?t=6190

And yes, I tried it after picking up one line of text about it whilst reading some book or other. I think it might have been Tim Rudman's printing course book, but when I investigated further, I found mention of it in quite a number of places.

I used the sodium carbonate / washing soda then (which is VERY cheap to buy, so well worth trying it out) to boost the d-max of not so new, but still totally usable papers, that weren't giving me a lovely decent black as I was getting with a freshly bought packet. In fact, it's still something that I add to my developer occasionally when using various papers that I have. It also is a major ingredient in a number of developers like D72 print developer, (which is well worth trying as it only requires a few chemicals and it means you can guarantee fresh print developer all the time. Try it instead of your Ansco 130.) It's ease is good for me, as I'm not a heavy printer and previously bought bottles usually went off before I finished them and having used it for a good while now, I can say that D72 is just as good and much cheaper than multigrade developers and I now make it up regularly to use in my Nova processor. It can also be used in washing clothes(! :smile:) and has various other uses around the house, so is well worth having a bag handy. I think I pay about £1 sterling for a kilo bag, from the corner shop. :smile:

Also, yes, it is a major accelerator ingredient in developers, so adding a good amount (= more than a pinch!) to maybe some older print developer will help, but why not just make up a fresh batch as mentioned above?

Terry S
 

markbau

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I've always found that adding 15 ml of 10% carbonate does "kick up the highlights" but it also seems to slightly reduce contrast in the highlights. I don't use it anymore.Perhaps it was an old salvage technique?
 

Don_ih

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Adding carbonate to used paper developer increases overall activity - it basically makes the developer work faster. If the developing agents are worn out, you will still end up with a muddy print. Adding benzo in conjunction with carbonate will restrain midtone and highlight development (more than development of black) so un-muddy the print a bit.
The real use of benzo is in good developer to get better highlights out of older paper. It cools tone, also. When you add bromide, you can end up getting a brownish tone. Adding any restrainer slows down development and carbonate will speed it back up a bit.
Carbonate can be used with a restrainer in good developer to deepen black and retain bright highlights. If you really want to deepen black, also add some hydroquinone.
There is no resurrecting spent developer. It can be used to dilute new developer for warmtone development - which carries over the benefits of any potassium bromide that's in there. Spent developing agents (metol, hydroquinone) don't get brought back to life.
 

Don_ih

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Nicholas Lindan

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That is due to the difficulty of dissolving benzo - it dissolves more readily in an alkaline solution.

That's interesting. I make mine up in 91% isopropyl alcohol. Benzotriazole makes a good treatment for bare metal surfaces before applying paint or adhesive.
 

Timberwolf

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That is due to the difficulty of dissolving benzo - it dissolves more readily in an alkaline solution.

Makes sense. Thanks. Would either carbonate or alcohol have a longer shelf life in solution with benzo?
 
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Neither BTA nor sodium carbonate will revive an exhausted developer; they are not developing agents.

Carbonate will accelerate developer activity. This may or may not give you more contrast depending on the paper used; usually no significant change with modern papers In any case, you'll need to adjust print exposure time (less exposure by a bit) if you keep development time constant.

BTA restrains development (slows it) somewhat proportionally. It can change contrast but, again, you'll need to adjust print exposure time (more exposure) if the development time remains constant. BTA can also gratifyingly clear whites in some cases, e.g., when developer fog or age-related paper fog is an issue.

Using BTA and carbonate together in the right proportion can keep you from having to adjust print exposure time, but finding the magic proportion isn't all that easy. It can be different for different papers, developers and developer age.

Much of this is moot these days anyway, since most of us are using VC papers and if one needs a bit of a contrast tweak, we just change filtration (and make the appropriate print exposure changes unless we've calibrated our systems). The whole BTA/carbonate thing works best for graded papers.

Still, I'll add a bit of BTA to my ID-62 from time to time just to get a different look on the toe of the paper, especially if there are lots of delicate whites I'm fighting with.

Best,

Doremus
 

Don_ih

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Would either carbonate or alcohol have a longer shelf life in solution with benzo?

I don't think either will degrade significantly. I've had a bottle of 1% benzo in water for a couple of years and it looks and behaves the same.
 
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