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  #21  
Old 15th October 2014, 07:25 AM
Ansel Ansel is offline
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Quote:
Originally Posted by Argentum View Post
if you are using distilled/deionised water then the precipitate is most likely good chemicals.

Question is how long it takes leaving stock standing before it starts to precipiatate out. The closer to a fully saturated solution the more likely it is for chemicals to precipitate out.

Just warm the stock solution and crush the crystals with your stirring rod and re-stir them back into solution. Its just as easy as filtering (almost).

Its present from freshly mixed and seems to get worse over time. Will try your suggestion see if it works, I guess I would then have to let the stock settle for a few days after heating?

What do you mean by "fully saturated solution"?
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  #22  
Old 15th October 2014, 10:03 AM
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photomi7ch photomi7ch is offline
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Quote:
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Its present from freshly mixed and seems to get worse over time. Will try your suggestion see if it works, I guess I would then have to let the stock settle for a few days after heating?

What do you mean by "fully saturated solution"?
This is where the liquid cannot hold the chemical suspended in solution. So when left it falls out creating a sediment. For example: PMK Pyro's B solution suffers from this big time. The way round it is to rotate the bottle until it dissolves again.
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  #23  
Old 15th October 2014, 12:58 PM
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Argentum Argentum is offline
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+1

fully saturated means the water won't hold any more chemical in solution no matter how much you warm it.

D76 shouldn't reach that point as far as I know.

If you have sediment left when you are mixing up your stock it is because you have some larger chunks of chemicals which will normally disolve if you crush them with your stirring rod.

Once any crystals/sediment forms they cause a snowball effect and make it easier for chemical to precipitate out. So when making up stock solution its very important to use correct temp, normally 40deg C, correct water volume and make sure there is nothing left to disolve otherwise precipitation will build up on the undisolved crystals.
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  #24  
Old 15th October 2014, 05:27 PM
Ansel Ansel is offline
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Thanks chaps. I still think there is something wrong with my latest batches D76 as I have not had this problem in the past...

Will be extra careful when mixing and try the filters also.
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  #25  
Old 15th October 2014, 06:12 PM
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Its good practice to leave newly mixed stock solution for 24 hours before using.

That way you will find out if anything was not dissolved properly and is going to precipitate out before using it.

AND

a word of caution about filtering. Any tiny particles such as dust or microscopic filter paper particles left in your developer will encourage precipitation/crystalation of your stock solution.

Its just like rain drops which form around dust particles in the atmosphere. Give the chemical something to attach itself to and it will say thank you very much and do exactly that forming little crystals.
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  #26  
Old 8th November 2014, 06:40 PM
Ansel Ansel is offline
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Hi all,

Brief update. Been a while since I have had any time to develop... have about 15 rolls ready to do. First two rolls went through today. Getting white spots again despite being extra careful mixing a new batch of D76, cleaning everything, etc. etc.

However, the spots are inconsistent. Not on all frames so I am thinking this is either a fixer or a photoflo/washing issue perhaps? If it was the developer it would be present on all frames, non? Or perhaps a combination of all three?

These are all from the same roll:

1. In this shot you can see the white dots on the boys shirt:
https://dl.dropboxusercontent.com/u/45915275/1.jpg

2. Whereas in this frame just a couple of specs on the woman arm:
https://dl.dropboxusercontent.com/u/45915275/2.jpg

3. And finally this frame is a total disaster (by the way that is my with M4 and a Leica Noctilux 1.2!
https://dl.dropboxusercontent.com/u/45915275/3.jpg

4. Whatever it is its really annoying, check the white dot on the woman hair:
https://dl.dropboxusercontent.com/u/45915275/4.jpg

Last edited by Ansel; 8th November 2014 at 06:46 PM.
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  #27  
Old 8th November 2014, 07:27 PM
Richard Gould Richard Gould is offline
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Ansel, I does not look like a developer problem to me, what film are you using, and do you use a Stop bath, some films react badly to stop bath, My favorite film, Fomapan, is a case in point, also, it is just possible it could be something in the wash water, it happens, so try using a plain water stop bath,using the Ilford washing method, and a final rinse in distelled water, also, it may be worth trying a different developer, try changing 1 thing at a time, that is the only way to get to the bottom of this problem, I have been using quite a lot of D76 lately, and I have not had a problem of any sort with it, As far as QC is concerned, Kodak no longer make their own chemistry, and haven't done so for a while, it was made by Champion for a while, and there is certainly no QC issues with them, and lately I believe it is being made by Tetenal, and again I can't see any QC issues with Tetenal, so I strongly think it could well be something other than the developer.for your information the batch number for my latest packets of D76, bought a month or so ago, is 1406155 and has an exp date of 2017 06 and states made in Germany, this is for 1 litre packets, I can only think of one other possible thing and that is you are somehow using very old stock, maybe expired, but that is a shot in the dark.
Richard
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  #28  
Old 8th November 2014, 07:36 PM
Mike O'Pray Mike O'Pray is offline
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We may be going round in circles here and my question may keep us spinning but have you looked at the problem negatives on a light- box with a loupe?

I take it that these scans are those of negatives reversed so I am assuming that on the negatives these are black spots.

When you dump the developer have you tried pouring it into a clear jar to see if there are black "ticks" in the liquid.

The other slightly strange thing is that unless these black "ticks" are sticking to the film for the full development period I'd expect them to take a few seconds to "stick" to the film and then move again on the next agitation but a white spot on the reversed neg and only in very few places suggests that there is only a very few ticks and agitation doesn't move them at all

Very strange. If none of my suggestions or questions bear any fruit then as a last resort try slow continuous agitation for the whole development time. If there are "foreign" bodies in the developer then continuous agitation should prevent them sticking.

Alternatively switch to ID11. Frankly if there are "ticks" in the developer I'd just dump it and move to some other developer

Best of luck

Mike
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  #29  
Old 8th November 2014, 07:39 PM
Ansel Ansel is offline
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Thanks. Its Tri-X @400. Wash is with distilled water. Fresh Ilfrod Fixer. Ilford stop bath. I could try with a water stop I guess.

Will try out all your other suggestions guys. Thanks.
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  #30  
Old 8th November 2014, 07:52 PM
Ansel Ansel is offline
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Quote:
Originally Posted by Mike O'Pray View Post
We may be going round in circles here and my question may keep us spinning but have you looked at the problem negatives on a light- box with a loupe?
No lightbox or loupe..

Quote:
Originally Posted by Mike O'Pray View Post
I take it that these scans are those of negatives reversed so I am assuming that on the negatives these are black spots.
I can't really see but yes, one would imagine that to be the case.

Quote:
Originally Posted by Mike O'Pray View Post
When you dump the developer have you tried pouring it into a clear jar to see if there are black "ticks" in the liquid.
I will try that. Thanks.


I will try some Rodinal tomorrow see if that runs OK
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