What's wrong with this picture?

[arnulf]

Hello people

I wasn't sure which forum to post this one in, since I quite honestly don't know where the problem lies, so I put it here.

Recently I've got some problems with very noisy shadow areas. I'm saying noisy because it looks a lot more like digital noise than film grain to me. Look at the attached file and see if you understand what I mean. I really don't know what that is, wether it's the film developing, the camera or the scanner process. The only thing I can think of is that it started happenig after I had my M6 repaired a couple of months ago, but I can not seriously see how that could have anything to do with it. The thing is that I've never had the problem until now.

It happens indoors in relatively low light only (not very low, though, and not always). I'm using a M6 with different lenses and Tri-x developed in D76 1:1 and scanned on a Nikon Coolscan V.

What is this? Anyone?

Arnulf

 

[mrb]

Hi Arnulf;

The problem is too many cameras. Way too many. More seriously, are you referring to the lower left-hand corner of the photograph? If so, I'd guess it's just the result of a tricky lighting situation. It looks pretty dark in that corner.

MB

 

[arnulf]

Thanks MB

It's actually more the upper part of the picture that disturbs me. Sure the light is a little low, but not that much, do you think. Look at this one. Much lower light, but the shadow areas are at least black, not noisy grey.

 

[mrb]

OK, comparing the two photographs, I see what you mean. And I don't know what might cause it. Tri-X and D76 are tried-and-true. It seems unlikely that the scanner is doing it, but maybe you should look at the negs closely, with a loupe. Some smarter folks (smarter than me, anyway) might come on line in the morning with better insight than I can offer. By the way, that is one cute baby!

MB

 

[eric]

What am I looking for?

 

[Tom A]

To me it looks a bit overexposed and to dense. The top is grayish rather than black. Run it through the scanner again and play with the curves a bit.

 

[arnulf]

Tom, I don't know. I agree that it can look a little like overexposure, but even adjusting curves or levels leaves that area grainy (or rather: noisy) even if the histogram clearly calls it black. I don't think it's an exposure problem.

Eric, do you really not see it? I have problems describing it better than I did in the original post. It couldn't possibly be a monitor thing, could it?

 

[Avotius]

I think its over exposure too, photo shop cant always help you make those bits magic, much easier to deal with a well exposed image rather then work it out later on. This noise seems typical of digital scanners that are having a hard time rendering out darker areas with transitions. Then again a under exposed negative on a scanner can give problems like this too but what I can tell you is that your M6 had nothing to do with this. Also maybe check your developers for freshness, you might have a icky batch there.

 

[Tim Gray]

I have a couple negs that I've scanned where I didn't push the blacks down black enough. The reason for the this was because I saw tantalizing information in the shadows that I wanted to preserve. The end result was grainy and not pure blacks. A wet print showed me that while some of this detail was indeed there, for the print (or scan) to work, I needed to crush the blacks to the point that I lost some of the detail. And the picture still looks good.

My advice - try using curves or levels to consign some of those areas to darkness, specifically the extreme top and bottom left corners.

 

[Jonathan R]

Going against the tide here, but is this negative actually relatively thin? The light source within the picture would have driven the exposure down unless you deliberately gave it more. And it doesn't look as though you did the latter because the deep blacks on the camera cases look pretty much devoid of detail. The fact that the drying mark shows up against a mid-tone also makes me wonder if it's a thin negative. In which case, maybe the scanner software has created or exaggerated shadow noise by expanding the density range of the whole picture. Just a suggestion - I know nothing for real about how scanners do their thing, just have to guess!

You also have quite a lot of flare or halation due to the light source, but at the moment I can't think how that would affect the noise problem that concerns you.

 

[Pherdinand]

it looks to me very much like VERY low exposure and trying to compensate for that with the scanner.
The second one where the light was low but looks fine is black in the shadows, because there are bright parts in the scene and the contrast is higher, thus the scanner is not trying to get information out of the black areas.

 

[arnulf]

Well, it certainly isn't ver low exposure. I always use the light meter on the m6, and getting quite good at choosing an exposure that's at the very least not far off.

The dark area at the top left really should be more black in my opinion. I tried using the eye dropper tool in the curves dialog box to darken it, but it still looks like digital dust. I don't get it.

And again: the weird thing is that this hasn't been happening before. Only the last two months (and, weirdly enough, ever since it came back from being repaired..) I've been getting these results. And not only with film I develop myself. Same thing happened on a BW400CN roll. The prints from the lab came out with the same result.

Hmmm...

 

[Matthew Allen]

What makes you so sure it's not under exposure? A light source like the flourescent tube in your photo will very often fool your meter, expecially if the meter's a fairly basic one like in the M6. Why not post a picture of the negative itself? My guess is it is on the thin side.

Btw, you mentioned BW400CN. My experience is that it's hard to overexpose this film but rather easy to underexpose it, which gives a lot of ugly grain and muddy blacks. I've taken to setting the meter to 200 and going from there when I use it as the results are much nicer this way.

Matthew

 

[arnulf]

Ok, "thin negative". What does that mean? Something wrong with it? I don't have it here now, but I can maybe post a picture of it later.

 

[pmu]

Exactly from where did you meter the light? I would bet my money on underexposure. That is the kind of grain you get from shadows when scanning underexposed negative. No way it is overexposed.

 

[Jonathan R]

Arnulf, 'thin negative' means not much density, compared with other negatives. In particular, shadows look almost transparent.

 

[arnulf]

Ok, I'll give another example here. These two images are taken with like a couple of seconds between them. If I did change the exposure, it wouldn't have been by more than one, MAYBE two steps, although I seriously doubt that. Would the difference be that big?

These shots were taken with Kodak BW400CN film.

 

[arnulf]

Sorry, forgot to attach the pics. Here they are

 

[uhligfd]

Yes, the second one looks underexposed. It is a quick givaway: washed out gray where it should be dark black. The first one looks exposed right. How do you modify exposure so suddenly and quickly? Why? It is the same light 2 seconds later, is it not?

 

[arnulf]

Yeah, that's the point! I really don't even remember changing exposure at all. It is indeed the same lighting situation. I always check the meter before shooting, and I'm pretty sure I'd remember if I had gone very far off what the meter suggested. For an image to turn out like the second one, it would have to be quite a few stops underexposed, right?