October 14, 2010

comparing film grain

I did some tests in order to evaluate the best film/developer combinations in terms of graininess.

Of course, there other factors that determine the choice of a particular film/developer combination: gradation, definition, sharpness, speed. The final decision is always a trade-off among these factors.

So I made a slightly different test. Instead of considering just the graininess of film, I evaluated how much film grain would be visible in the final print, where the enlargement factor comes into play.

For example, if I'm using medium format I could tolerate a more grainy film if I realize that it will give a better acutance. In fact, the extra graininess will be less relevant on MF owing to the reduced enlarging factor.

Results are shown below, grouped into two sets: 120 film (medium format) and 35mm film.

The small images represent 5x5cm crops of full size images with 127cm largest side for 35mm film, or 144cm largest side for 120 film. On a 115-dpi monitor these crops should be rendered approximately in their real dimensions.

How to use these tests:
  1. if you just intend to compare graininess of film/developer combinations, only make comparisons within each group (120 films or 35mm films).
  2. if you are concerned about the graininess that will be visible on the final print, make comparisons within both groups.
  3. in both cases, evaluate these images from a reasonable distance (~50cm)

120 films

FP4+
125 ISO
in D76 stock
FP4+
80 ISO
in XTOL 1+1

ACROS-100
100 ISO
in Rodinal 1+50
Fomapan 100
100 ISO
in Rodinal 1+50















35mm films

TRI-X
400 ISO
in XTOL 1+1
TRI-X
800 ISO
in XTOL 1+1
TRI-X
1600 ISO
in XTOL 1+1
TRI-X
3200 ISO
in XTOL 1+1


HP5+
400 ISO
in XTOL 1+1
TRI-X
400 ISO
in D76 stock
TRI-X
3200 ISO
in D76 stock
Tmax-100
100 ISO
in  D76 stock













Some considerations
  • on 120 film 
    • the FP4 exposed at 80 ISO and developed in XTOL 1+1 is my preferred choice
    • the ACROS 100 in Rodinal 1+50 is also valid combination, especially in terms of acutance, but I have to find some tests in order to find the actual film speed and the best developing time
    • the FOMAPAN 100 shows a lot of grain
  • on 35mm
    • the TRI-X in XTOL 1+1 is my preferred choice
    • the T-MAX shows the finest grain (unfortunately I'm not so happy about the tonal range on the highlights)

Test conditions
  • 35mm film was scanned on a Nikon Coolscan V ED at 4000dpi, producing a file of ~5600x3800 pixels (125x83cm at 115dpi)
  • 6x6 film has been scanned on an Epson V700 at 3200dpi, producing a file of ~6600x6600 pixels (145x15cm at 115dpi)
  • a ~230x230 pixels crop has been extracted in a significant partt of the image (this should be rendered as a ~5x5cm square on a 115-dpi monitor)
  • no sharpening was applied at any stage
  • the difference between the V700 (flatbed scanner) and the Coolscan V ED (dedicated film scanner ) is quite evident: the grain looks soft on V700 scan.

1 comment:

  1. Really helpful. I was looking for a sharp result. Perhaps you could test even more film-developer combinations especially using 35mm film.
    Thanks a lot! Keep using film, it's great!

    ReplyDelete