Simple question about underexposed negatives and "noise"

[rpavich]

Advertisement (gone after registration)

I was just surfing some low light B&W images online and noticed that one some, there was a lot of "noise" in the shadows. I know from my own experience that when my scanner tries to adjust the underexposure, that's what happens.

So a question occurred to me; what is the effect of an underexposed low light shot when printing with an enlarger?

Will there be some specks in the shadows?

I'm just asking out of curiosity, I've never (not yet) printed that way.

Edited January 3, 2016 by rpavich

[adan]

Came up, indirectly, on the Film Forum a few months ago. http://www.l-camera-forum.com/topic/250547-blotchy-blacks-on-scanned-image/

 

Basically, the extra optical stage in chemical printing, and to some extent the different tonal curve, make shadow grain or noise less visible.

 

More or less - the gelatin coating on the paper is less precise than a scanner's silicon pixels. The light from the enlarger gets diffused a bit in the gelatin, so individual grains in a large clear area (negative shadow area) get "blown out" by the surrounding light.

 

(Conversely, grain in the highlights - small pinholes in a dense negative area - tend to be a bit bigger and more noticeable. And before anyone gets upset - in the mid-tones and highlights, photo paper (by my own tests) can resolve about 400 lines per inch, whereas inkjet printers give about 240-360. But in the shadows, with lots of light spilling around, that goes down).

 

If you make a really light, underexposed print, (or have a really low-contrast image - e.g. taken on a foggy day with no black areas anyway) you can see the shadow grain or "noise" more easily, as gray speckles on a darker gray background.

 

http://www.tpub.com/photography1/14209_files/image526.jpg

 

All of this depends, of course, on which film, how well the film was exposed, and how hard you are trying to "rescue" shadow detail. And those factors apply to a scan as well. These days, scanning 120 film, I go for a "generous" camera exposure, such that all of the image area has some density above unexposed film. This prevents thin shadows where the individual grains stand out when scanned.

 

A couple of years ago, I saw some original Koudelka prints from the 60s-70s. And was reminded of just how little we tried to "rescue" shadow details back then. "Dynamic Range" was something the audiophiles worried about. We printed for a pure black in the densest area, and if that meant half the image was pure black, and "grays" didn't kick in until half-way up the tonal scale - so be it.

 

https://artblart.files.wordpress.com/2014/09/josef-koudelka-gypsies-b-web.jpg

 

http://www.pacemacgill.com/gfx/images/jk/large/JK170.jpg

 

http://museumexcursion.com/wp-content/uploads/2015/02/gm_348212EX1.jpg

 

[edit - Oh, occasionally we'd need to pull up some particular shadow detail, and go whacko with the ferricyanide bleach - and the noise would show, at least in 35mm pictures http://jbhphoto.com/blog/2012/09/16/selective-bleaching/ ]

Edited January 3, 2016 by adan

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[rpavich]

Thank you so much for your comprehensive reply!

The examples of total black in the shadows is food for thought, very interesting.

[M.Hilo]

One thing that has to do with your question is the lighting of the print you are looking at. The more, or less, watts of the lamp you use; the intensity of the daylight when not using artificial light.

 

You will have noticed different computers show your image files in different ways: it is like that with prints too. Scanners often see more than we can see. I have had many b/w fiber prints scanned, often 50X60cm and scanned by an enormous Fuji drum scanner, that takes up most of quite a large room. I prefer to have prints scanned because then my printing ways / solutions / grain are included. Often the rough scans showed much more than I ever saw in the darkroom, or just afterwards. What probably showed first as a deep black part could be quite grey with grain and retouch showing.

 

When preparing such image files for reproduction in books, you work with a lithographer, or a pre-press person. It is a complicated art in itself, this process. Next to the computer screens will be a set-up to hold the original with a lot of light on it. For the maker, the photographer, this is often confusing: the print is shown with so much light, it looks very different from the print you saw in your own space.

 

That brings me to your question. When it concerns prints, or image files on the screen, everything is subjective. There's no truth, just personal taste and preference.

 

The previous poster's Koudelka prints will look beautiful to him, and much too contrasty for those who want to see every shade of grey and black and white. William Klein's New York and Rome 1st editions books are full of contrast, very black and very white, with lots of what you would probably consider noise. And as such these books are very beautiful. However, the prints he made at the time are much more subtle. Klein accepted the gravure printing of his work in the books would be different from the prints he made, and he probably pushed it even further. It was his choice of how to communicate the whole.

 

Moriyama's Goodbye Photography was printed in 1972 and it is a movie-inside-a book filled with contrast and lots of "noise". Not many years ago this book was reprinted and the images were all more subtle, with much less noise and "more of recent time quality". Some will marvel at these reproductions, I found this reprint had lost almost all it's soul.

 

Sorry if I am not clear and have turned your simple question into something complicated. I guess I do so because I think it is better to approach this question from a personal emotional point of view, than from a technical point of view.

[philipus]

Great post Andy, thank you. I overexpose virtually all my ISO 100-400 135-films two stops and have them developed at box speed but I'm thinking there could be situations I could go even to three stops. I haven't tried this in my Hasselblad yet though so any experiences or suggestions you have regarding 120 film would be very interesting to hear.

 

Br

Philip

 

These days, scanning 120 film, I go for a "generous" camera exposure, such that all of the image area has some density above unexposed film. This prevents thin shadows where the individual grains stand out when scanned.