Streaks on negative scans

[jayeeflo]

On multiple occasions I have encountered steaks on my scans of negatives that I have processed in the Tetenal Colortec C-41 kit. An example of the problem is shown in the attached scan.

As a logical first step to fix the problem I thought that I may not have washed the film entirely properly and therefore tried washing again in the six exposure strips which proved to be a terrible idea as everything stuck to each other. Never again. I have since used iso-prophyl alcohol to clean my negatives and this has proved to be a great fix for these streak patterns. However, this roll of film has been a stubborn one.

The wretched streaks showed up again and I went to clean the negs for a second time with the IPA, but to no avail. No matter how much cleaning with the microfibre cloth and IPA I tried, the streaks have stayed their ground. I am stumped as to how I might shift them, and thoroughly annoyed seeing as it's a mate's roll of film he is paying me to dev and scan. I don't think it can be damage to the emulsion as it has disappeared in the past.

If anyone has any ideas on how to get rid of these streaks or have had any experience in this I would very much appreciate some help.

As a side note: the placement of the streaks is always in a similar spot. Always stretching out from left to right and always in the middle on the vertical axis as shown in the example scan.

 

[Patrick Robert James]

Those look like newton rings to me. Right down the middle would make sense if you are using a flatbed scanner. They are caused by the film touching (or nearly touching) the glass. Invert the neg so the emulsion is towards the glass. That should fix your problem.

 

[jim10219]

Yeah. Those do look like Newton rings. I switched to wet mounting all of my film because many of the films I use will show those no matter which side I have touching the glass.

They also make anti-Newtonian glass which is glass with a slightly rough surface. That rough surface degrades the scan quality though, so I avoid that.

A third way to avoid those is to use a film holder that gets the negatives up off the glass, so they don’t touch it. I’m guessing you’re already using a film holder due to the location and consistency of those. I’m also guessing that they’re sagging down in the middle and touching the glass where those rings are showing up. You might try to find a way to get your negatives to mount a little tighter in the holder so they don’t sag. Or raise the holder a smidge, so they don’t touch.

In any case, good luck! I spent a couple of months fighting that problem before I gave up and switched to wet mounting.

 

[pentaxuser]

All I can see on my monitor is a thin streak from midway up the left hand side going directly across. I lose sight of it before the first glass or it disappears. Is this the one to which you refer? If so it doesn't look much like any Newton's Rings I have ever seen on my prints. I cannot say what Newton's rings look like on a scanner but I think you are saying that the streak is clearly visible on the negative so while it is possible a scanner might replicate this and indeed should do so if it is there on the negative it isn't solely an artefact of the scanner. Is this a reversed scan of the negative we are seeing?

From a 100% analogue aspect, involving optical printing from an enlarger, Newton's rings are interference aren't they and can be there from perfect negatives but if I understand the OP correctly these are actual real streaks on the negative which he has been unable to remove

Thanks

pentaxuser

 

[Murray Kelly]

You don't actually say if you can see the marks on the film. Nor do you say if it's flatbed scanner. I had a problem, worse than you have, due to some marks on the calibration window at the top of the film strip holder. The scanner put those marks all the way down the strips until I woke up to it.
Try the IPA on the calibration window and see if that helps. Good luck with it. Bad for your image if your friend twigs that there is something wrong.

 

[Craig75]

I just had exactly same thing - only with enlarger and negative carrier - took out a strip of 6 negatives - could see a lil mark on one i wanted to print - cleaned it - put it in glass negative carrier and exactly same thing - other 5 were fine but one i had to clean showed up newton rings.

 

[Murray Kelly]

Jay, they don't look like any Newton rings I've ever seen. The marks are from the scanner or on the film
Try inverting the film (emulsion down) OR (not and)
Flip it end for end.
If the marks move it's the scanner and apart from dirt on the calibration window inside or out, you are on your own. Sorry.
If it is the film have a good look at the cassette and ask to look at the camera for bits of film or something around the film gate and rollers or pressure plate.
You mention you've had similar before that was corrected but I cannot offer anything there. Only you can work that out.
Again, good luck with the sleuthing.

 

[mshchem]

Make a contact print. Black and white or color. See if it'd really there

 

[jayeeflo]

You don't actually say if you can see the marks on the film. Nor do you say if it's flatbed scanner. I had a problem, worse than you have, due to some marks on the calibration window at the top of the film strip holder. The scanner put those marks all the way down the strips until I woke up to it.
Try the IPA on the calibration window and see if that helps. Good luck with it. Bad for your image if your friend twigs that there is something wrong.

I realise I didn’t specify means or my diagnosis.. I couldn’t ever see marks on the film when using a loupe, but persisted with some of the past rolls and somehow IPA worked. I’ve been using a flatbed scanner so I’m pretty sure it’s going to be these Newton Rings everyone’s talking about. If that falls through I’ll check out the calibration window.
Cheers for your input!

 

[jayeeflo]

All I can see on my monitor is a thin streak from midway up the left hand side going directly across. I lose sight of it before the first glass or it disappears. Is this the one to which you refer? If so it doesn't look much like any Newton's Rings I have ever seen on my prints. I cannot say what Newton's rings look like on a scanner but I think you are saying that the streak is clearly visible on the negative so while it is possible a scanner might replicate this and indeed should do so if it is there on the negative it isn't solely an artefact of the scanner. Is this a reversed scan of the negative we are seeing?

From a 100% analogue aspect, involving optical printing from an enlarger, Newton's rings are interference aren't they and can be there from perfect negatives but if I understand the OP correctly these are actual real streaks on the negative which he has been unable to remove

Thanks

pentaxuser

Yes, that’s the one. There were no obvious signs of dry spots or leftover chemicals but IPA was the only solution I could think of at the time so it was a bit of a Hail Mary attempt.
This scan isn’t a reversed scan, just as the film holder tells.

Cheers for your input, pentaxuser!

 

[jayeeflo]

I just had exactly same thing - only with enlarger and negative carrier - took out a strip of 6 negatives - could see a lil mark on one i wanted to print - cleaned it - put it in glass negative carrier and exactly same thing - other 5 were fine but one i had to clean showed up newton rings.

Yikes. Good luck with that one man.

 

[jayeeflo]

Those look like newton rings to me. Right down the middle would make sense if you are using a flatbed scanner. They are caused by the film touching (or nearly touching) the glass. Invert the neg so the emulsion is towards the glass. That should fix your problem.

Thanks so much for your input, this was exactly the problem! I came back to some much flatter negatives and didn't even have to flip them. Thanks once again.

 

[jayeeflo]

Yeah. Those do look like Newton rings. I switched to wet mounting all of my film because many of the films I use will show those no matter which side I have touching the glass.

They also make anti-Newtonian glass which is glass with a slightly rough surface. That rough surface degrades the scan quality though, so I avoid that.

A third way to avoid those is to use a film holder that gets the negatives up off the glass, so they don’t touch it. I’m guessing you’re already using a film holder due to the location and consistency of those. I’m also guessing that they’re sagging down in the middle and touching the glass where those rings are showing up. You might try to find a way to get your negatives to mount a little tighter in the holder so they don’t sag. Or raise the holder a smidge, so they don’t touch.

In any case, good luck! I spent a couple of months fighting that problem before I gave up and switched to wet mounting.

Thanks for your input Jim, this was the problem. My negs were heaps flatter when I returned to do some more scans so all was well and no rings to be seen. I'll definitely look into wet mounting because this Newton Ring crap is infuriating.

 

[jayeeflo]

Jay, they don't look like any Newton rings I've ever seen. The marks are from the scanner or on the film
Try inverting the film (emulsion down) OR (not and)
Flip it end for end.
If the marks move it's the scanner and apart from dirt on the calibration window inside or out, you are on your own. Sorry.
If it is the film have a good look at the cassette and ask to look at the camera for bits of film or something around the film gate and rollers or pressure plate.
You mention you've had similar before that was corrected but I cannot offer anything there. Only you can work that out.
Again, good luck with the sleuthing.

I came back to some much flatter negatives and no streaks to be seen, so it seems like the problem was Newton Rings. Thanks for your input.

 

[Murray Kelly]

Very good. Nice to see the problem solved. Sometimes we never hear what happens!. Just as well I didn't put any money on it.

 

[TonyB65]

A little tip on watermarks on your negatives, I occasionally get them and remove them by rubbing the negatives (dry) on some denim, takes a few seconds and works a treat, it's always worked for me anyway.