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Ken Lee
18-Feb-2009, 10:21
Is there a way to quantify the apparent graininess of TMX versus TMY ?

... that is, given equivalent "normal" processing in the same developer, etc.

Looking through some images I made a few years back, on TMX, I was a bit surprised to see that the TMX photos were noticeably more detailed and grainless in appearance, even when scanned on my Microtek Artixscan 2500 - which delivered close to the stated resolution in the green channel. This is the older TMY, of which I still own a few boxes.

I know I can make a test for myself, but can the difference be stated in lp/mm or some other convenient measure ?

Oren Grad
18-Feb-2009, 10:40
Ken, get the Kodak data sheets and look for the paragraph labeled "Image Structure", where they have both a resolution spec and an RMS granularity rating for each film, for negatives developed in straight D-76.

I've not yet tried TMY-2, but I have used both TMX and TMY as well as many other B&W films. From a purely subjective perspective, and even taking into account its ISO rating, TMX has always looked qualitatively different to me, with its grain pattern somehow disproportionately subdued compared to that of any other B&W film I've used.

I've always found TMY to be challenging because of its curve shape and hyper-responsiveness to development changes. But its grain structure doesn't stand out for me in the way TMX's does.

Ron Marshall
18-Feb-2009, 11:16
There was a comparison done in an issue of View Camera in 2008 (can't find it now).

What the author stated, if I remember correctly, was that for prints smaller than 24x30 one would not see a difference between TMY-2 and TMX.

venchka
18-Feb-2009, 11:35
There was a comparison done in an issue of View Camera in 2008 (can't find it now).

What the author stated, if I remember correctly, was that for prints smaller than 24x30 one would not see a difference between TMY-2 and TMX.

Sandy King wrote the article. I think I remember he said larger than 32x40 to see any difference.

Which begs the question: Is there anything about TMX to justify using it over TMY-2 with it's 2 stop advantage?

Bruce Watson
18-Feb-2009, 11:57
I'm just wrapping up some testing of TMY-2 in 5x4. I'm comparing it to Tri-X though, not TMX. Both processed in a 3010 tank on a CPP-2, XTOL 1:3, 20C, 30 rpm. Did the EI and "N" testing for both to get as close as I can to an apples-to-apples comparison.

What I'm seeing is that TMY-2 is a better film in just about every way that matters to me. It's sharper, less grainy, more linear (if that makes any sense; it just "feels" like it does a better job of translating the scene's HSB levels into density levels on the film), and has clearly better reciprocity characteristics. My shadows used to drop out with Tri-X if my exposures were under around 1/4 second. This doesn't happen with TMY-2, so I'm thinking it wasn't my metering technique -- it was reciprocity failure happening just in those shadow areas.

How it compares to TMX I don't really know -- what little TMX I used was really sharp and really fine grained. But with either film I'm usually lens limited (diffraction) anyway, and I'll trade 2 stops of real film speed for a little more graininess any day. But it's the tonality that will sell it. And I really like the tonality I'm gettin'.

EDIT: I should add that based on what I'm seeing so far that my new film is going to be TMY-2. And I've had an off-list conversation going with another forum member here to discuss whether there was a reason to use TMX or whether we should be using all TMY-2, all the time. We both pretty well concluded that TMY-2 is probably going to become our only film.

EDIT2: I should also add that it drum scans just beautifully. Easily smoother than my old Tri-X. For whatever that's worth to anyone.

venchka
18-Feb-2009, 12:00
One more time...

Thank you Bruce! I can understand everything you said. Your conclusion makes perfect sense to me.

Eric Leppanen
18-Feb-2009, 12:22
Sandy King compared TMY and TMY-2 in the March/April 2008 issue of View Camera magazine. He concluded that TMY-2 provides a significant improvement in grain size versus TMY. He also noted a significant improvement in sharpness when used with his rollfilm camera, but much less so with his 4x5 (presumably due to diffraction, etc.). He did not compare TMY-2 with TMX.

I will standardize on TMY-2 as my standard B&W film for all LF formats, once I use up my remaining supply of TMX readyloads. For me, the speed of TMY-2 is far more important than a slight increase in grain versus TMX (not a factor for me anyway since I rarely print B&W larger than 16x20), and its reciprocity characteristics are a godsend compared to Tri-X, HP5+, etc.

BarryS
18-Feb-2009, 12:37
I use TMX as my primary large format film and haven't found any other film with such fine grain and smooth tonality. I tried TMY and didn't like it, but based on Sandy's article, I bought some TMY-2. I was a little surprised at the qualitative differences between TMX and TMY-2--they're very different films. I much prefer TMX and agree with Oren that it's a unique film. To me the differences go way beyond speed.

Ken Lee
18-Feb-2009, 13:21
When I returned to photography a few years back, I went with TMX + D-76. Later, I switched over to TMY and PyrocatHD, but never performed an "apples and apples" test.

One of the reasons I went with TMY + Pyrocat HD, Sandy King's superb research which demonstrates the excellence (http://unblinkingeye.com/Articles/PCat/PCat4/pcat4.html) of the combination: its almost linear curves, etc.

Now I will, because in looking over my earlier work, I see aesthetic differences in certain images, which are not solely, as Barry has said, a matter of speed, or even of graininess or detail.

sanking
18-Feb-2009, 14:07
For the record my comparisons of TMY and TMT-2 and of TMY-2 and TMAX-100 were based on development in D76 1:1. The use of a staining developer like PMK or Pyrocat-HD would have introduced a number of issues that were better avoided IMO. My conclusions have been stated pretty accurately in this thread.

1. TMY-2 is an improvement over TMY in terms of both grain and resolution, though the difference is significant unless you plan to print large.

2. TMAX-200 has finer grain and higher resolution than TMY-2, though again you must print fairly large to see any diffference.

3. The curve families of all three films are very similar in D76 1:1. Very short toe, long straight line, and short shoulder. I found virtually no difference in curve shape between TMY and TMY-2.

4. Grain depends on many factors, including exposure, developer and type of development. It also depends on how the film is printed and /or scanned. I would not expect others to necessarily reach the same conclusions that I reached about the appearance of grain, whether they print directly in the darkroom or scan the film. My observations are based on a scan with a high end CCD scanner at 5080 spi with fluid mounting. This gave files with very smooth grain capable of a lot of enlargement with all three films.

Sandy King

Ken Lee
19-Feb-2009, 06:21
Thank you all.

It may well be that the subjective differences I see, stem more from lighting and choice of subject, than from choice of film/developer.

This weekend I'll try shooting the same subject at the same time, to see what differences, if any, arise.

Toyon
19-Feb-2009, 06:54
Wasn't Kodak supposed to revise its tmx 100 emulsion for finer grain? I checked the website, and Kodak makes no such claims for its current film. If that change is coming for 4x5, any testing would be made moot once the new emulsion is released.

Ken Lee
21-Feb-2009, 07:48
I just dug up an apples/apples test I already made a few years back.

As usual, it's like Sandy says.

The TMX/TMY negatives are not identical, but once I scan them and adjust for the black film edge, it is trivial to make them look the same.

sanking
21-Feb-2009, 08:55
As far as I know the TMAX-100 emulsion was not improved for finer grain as was TMY. However, Kodak has put the same little red label on boxes of Tmax-100 that was put on the TMY-2 boxes to indicate the newer film. That may have lead some people to believe there was an actual change in the film.

Sandy King



Wasn't Kodak supposed to revise its tmx 100 emulsion for finer grain? I checked the website, and Kodak makes no such claims for its current film. If that change is coming for 4x5, any testing would be made moot once the new emulsion is released.