Black pinpoints on developed negatives - why?

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corot

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I have just developed a roll of FP4 in ID-11 1:1 in a spiral tank. Everything came out fine except for tiny black pinpoint dots. These dots are barely evident in a slide viewer, but they are noticeable through a 8x loupe. Some negatives seem to be more affected than others.

Any thoughts on what may have gone wrong?

Thanks.
 
Without seeing thm I can only guess. It could be that you used a powder developer, and did not completely mix the powder. Or there could be a contaminant in the developer. Since the spots are black (and assuming it's not black things adhered onto the surface of the negative) it has got to be a fault in the development and not one of the other steps.
 
Do you live in an area of hard water? Sometimes, it's caused by air bubbles on the film. I was having these despite banging the tank to dislodge them. I now presoak my film for one minute or so, and that seems to have taken care of it.
 
Thanks everyone for your replies. Unfortunately I don't have a scanner to show you the results.

Yes, it was a powder (ID-11) freshly made just before using, and we have slightly hard water. The dots (dozens of them on each negative) look like overdeveloped micro-spots, so the suggestion of poorly mixed powder is no doubt correct. Another lesson to remember!

I like the story about the bird!
 
corot said:
Thanks everyone for your replies. Unfortunately I don't have a scanner to show you the results.

Yes, it was a powder (ID-11) freshly made just before using, and we have slightly hard water. The dots (dozens of them on each negative) look like overdeveloped micro-spots, so the suggestion of poorly mixed powder is no doubt correct. Another lesson to remember!

I like the story about the bird!
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If it happens today, we just clone it out. ;-)

I did get contamination once, the bottle cap of a bleach bottle had some residual silver, sent the film to Kodak and they nailed it.

Color transparency processing required a lot of bottles and I was recycling what I had.

Sometimes mixing directions tell you to stir until dissolved, and I did not have a "mixer" at home, so I ended up resorting to shaking the bottles to mix, never told anyone until now, but yes, I shook and inverted my bottles to get all those crystals into solution. Another reason to use glass bottles, you can see the crystals if they are not dissolved yet.

John
 
mabelsound said:
When I mix D76, I always heat it up by placing the jug in a pan of water on the stove. The powder dissolves much faster. don't let it get too hot though!
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Good tip, I'll try that.

JohnTF said:
Sometimes mixing directions tell you to stir until dissolved, and I did not have a "mixer" at home, so I ended up resorting to shaking the bottles to mix, never told anyone until now, but yes, I shook and inverted my bottles to get all those crystals into solution. Another reason to use glass bottles, you can see the crystals if they are not dissolved yet.

John
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I'm absolutely, positively, one hundred percent sure (!) that I read in a leaflet that it is normal for there to be some undissolved crystals. But of course I may be wrong. (I tell my students, as I was told when I was a student - "Sometimes I will say A, write B, mean C, whereas D is correct.")

I just hope that the remainder of the stock has been standing long enough now for the crystals to have either dissolved or settled out.
 
corot said:
Good tip, I'll try that.



I'm absolutely, positively, one hundred percent sure (!) that I read in a leaflet that it is normal for there to be some undissolved crystals. But of course I may be wrong. (I tell my students, as I was told when I was a student - "Sometimes I will say A, write B, mean C, whereas D is correct.")

I just hope that the remainder of the stock has been standing long enough now for the crystals to have either dissolved or settled out.
Click to expand...

I always use hot water as well to mix, am pretty sure no crystals left, they settle out so you can see them in the bottom of a glass bottle. OTOH, I believe my standard funnel is one with a fine stainless strainer.

When they finally dissolve, I can see some differences in density, and as the solution was made in hot water, it normally stands over night before use.

As I recall, they look needle like, as in Hydroquinone crystals, but I really do not know what component is the hardest to dissolve.

John
 
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