Does this look like a scanner issue?

jbharrill1

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I got my test roll back from my "new to me" leica CL and was pretty happy with the results until I looked a little closer and started noticing horizontal dark bars running across the entire length of about half of the photos in the same spot about 2/3 of the way up the photo. I have looked over the negatives and don't see anything resembling the bars, but I also feel like they might be somewhat hard to spot to the naked eye. Some of the photos are worse than others,while some of the brighter "more busy" photos you can't see anything, but in some you can see how there are more bars near the bottom. Below are a few examples where the bar is really standing out. I've done a little research and it sort of looks like "banding" from scanning but all of the examples I've seen run vertically and not horizontally.

x2528g.jpg


2ee8uwj.jpg


2n2456q.jpg


I did not develop or scan these images.

Does this look like a scanning issue, an issue during the development process, or something that the camera is doing? At first I thought light leak but that would mean the bars would be brighter and not darker.
 
Of course it is hard to tell from what you have given us. But I'd bet it is lab error before I'd blame your camera. Scanning is a difficult 'art' so maybe find someone you know that is experienced in scanning or send the negatives to someone here that would like to help. I'll do it, but maybe someone else on RFF will jump in with a better idea. If you do send someone the negatives be sure to send some that are taken in daylight.
 
I did have a similar problem with a Leica M6TTL that required a Leica repair. However the advice to check the film / processing lab by trying others is sound.
 
Those negs are all underexposed. You can tell by the muddy dark tones. Streaking like you're seeing is sometimes seen in underexposed films.
 
Those negs are all underexposed. You can tell by the muddy dark tones. Streaking like you're seeing is sometimes seen in underexposed films.

Streaking isn't a function of exposure. It might make it more pronounced but this is a mechanical issue either in camera or scanner.

Rescan some of these but turn the neg 90 degrees on the bed from how you positioned them before if you're using a flatbed. If you're using a dedicated film scanner flip the negs so the emulsion is in the reverse position. Scan a blank frame also. If the steak appears in a different spot it's the scanner if in the same it's the camera.

Also you could take one frame with and one without streaks and scan them several times each and see if the streaks appear or disappear or change each time. I so it's most likely scanner if not it's most likely camera.

You didn't say what scanner your using.
 
Streaking isn't a function of exposure. It might make it more pronounced but this is a mechanical issue either in camera or scanner.

Rescan some of these but turn the neg 90 degrees on the bed from how you positioned them before if you're using a flatbed. If you're using a dedicated film scanner flip the negs so the emulsion is in the reverse position. Scan a blank frame also. If the steak appears in a different spot it's the scanner if in the same it's the camera.

Also you could take one frame with and one without streaks and scan them several times each and see if the streaks appear or disappear or change each time. I so it's most likely scanner if not it's most likely camera.

You didn't say what scanner your using.


I've found it common on underexposed color negs processed in minilab processors. Its not an exposure problem, but a processing one (uneven developing) that shows more on underexposed films.
 
I agree with Chris and X-Ray, "thin" underexposed images (assume that these are color neg) exasperated by some mediocre development.

Underexposure will show more dust, scratching and uneven development marks. If indeed these are color negative, it would be better to error on the side of overexposure. Color neg can handle overexposure quite well. It wouldn't hurt to check your meter's accuracy.
 
I agree with Chris and X-Ray, "thin" underexposed images (assume that these are color neg) exasperated by some mediocre development.
...

I think it is an illumination fault in the scanner that is being exasperated by the underexposed negs. Dust, or other schmutz, in the scanner's illumination system would be way out of focus and could yield this type of dark line. It would have been a spot if the neg was duped in one shot (e.g. DSLR duping) but would result in a linear fault in a scanner that moves the film past a fixed sensor and illumination system.
 
Other than the obvious underexposures on the negs, it is a scanner fault. I recently had a roll of b&w with similar bars running through the roll, only more pronounced than yours. It happens. Just have the lab re-scan them.

I once had a scanner fault from the lab where it looked like there were green laser beams blasting out from an airport control tower I had photographed. Now that was a cool image.

PF
 
It could be the scanner CCD is defective. However, this sort of banding noise is usually a bit more random and causes color rendering errors as well.

We have two different types of exposure going on here. One is the film and the other is the scan.

I will assume the horizontal bands are not in the negatives.

To avoid semantic issues, I suggest the issue involves the signal-to-noise ratio of the scan's raw file.

If we define noise as errors in the data, there are two types of noise: pseudo-random noise and correlated noise. The latter are often called artifacts. In this case, horizontal rows of the data appear to have correlated noise. In the banding region, the signal-amplitude estimates are wrong.

The band is not visible in brighter regions.

Darker regions have a lower signal to noise ratio.

This could mean part of the total noise responsible for the artifacts are below the analog-to-digital converters detection threshold when the signal level is high. This is easy to observe with any digital camera. Take a photo with the lens cap on. In post-production viewing maximize the image's global brightness. You will see a variety of artifacts. But when there is sufficient signal (light) the artifact DC voltage levels are below the ADC's minimum detection threshold. Now, they are not present in the raw file.

Or, for some reason, the scanner light source (signal level) is lower for just the banding region.

If the cause is electro-mechanical (the scanner's light becomes lower for the banding region) then the issue is a loss of signal. If there is a problem with the CCD, then it's due to correlated noise.

Either way, it's a S/N problem.
 
Underexposed negatives or worse transparencies are a big problem for scanners. This is a scan of a underexposed E-6, the scan looks way worse than the original (it just looked dark)(I just let the scanner decide):

ColorPerfect rescue by John Carter, on Flickr

I opened in ColorPerfect with zero adjustment; just opened it:

ColorPerfect rescue by John Carter, on Flickr

So even horrible scans can be brought back to life.
 
I've found it common on underexposed color negs processed in minilab processors. Its not an exposure problem, but a processing one (uneven developing) that shows more on underexposed films.

That's roller marks from dirty or worn out parts. It's just more apparent in low density areas. Many mini labs don't do proper maintenance on their machines.
 
Provided this is color neg, if it's caused by dirty rollers at the lab or similar it would cause increased density in the neg from the deposited Kurd. This would result in lighter bands when scanned. Again provided it neg film you can rule out krud.

Every CCD failure in a scanner that I've seen or dirt on the CCD which I've had resuktscin a sharply defined black line going the direction of the scan. These are not sharp edges well defined marks and are not black as would be the case with trash on the CCD. Rule that out.

It is possible that there were voltage fluctuations at the time they were scanned. If the circuit isn't regulated it could result in poorly defined dark bands. But if it appears in multiple scans in the same place you can rule that out. In addition the location of the bands would depend on the orientation of the negative when scanned. If scanned a second time there would be a different banding pattern or no band st all.

It's possible that it's software or an electronic issue in the scanner. A good way to tell is reorient the neg 90 degrees and scan again or if you can't just flip the emulsion position and scan again. If it's still there in the same place then it's in the neg and most likely camera related. If it appears but 90 degrees to the original scan then it's a scanner problem.

Dont over think this. It's not that complicated. The above test will tell or narrow the problem down. Also you could go back and scan some old negs and see what happens. No bands, most likely in the camera.
 
Thanks for all the respones everyone.

X-ray, I did not scan these myself, they were scanned at the lab where they were processed. I am going to pick up some more film that i dropped off for processing a few days ago hopefully today and I'll mention this to them and see if i can get them to rescan/rotate the negatives to see if it is indeed the scanner. Like I mentioned earlier this was just a test roll that I shot in about 45 minutes of walking around the yard and neighborhood so I'm not upset that the scans came out looking this way, but will be upset if it is a camera malfunction.
 
So I think I've decided that this issue was caused be the scanning. I don't have a flatbed scanner suitable for scanning negs nor was I able to swing by the photo lab today so I did my best to do some iPhone scanning. This is the result, I know it's not the best but I think that I can safely say I don't see the darker bars. Am I tripping or are you guys in agreement that they don't seem to be there (from what you can tell, I know it's a pretty rough image)

fcuw0.jpg
 
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