Holy grain, Batman! (Big file warning.)

S

Stephanie Brim

Mental Experimental.
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Tri-X. Rodinal 1+50. ISO 200. The results are nowhere near as pretty as I think they should be. Thoughts? Other than the film being pretty old, I can't think of other explanations. I think that's the reason.

trix_carvacuum.jpg

trix_fourtrees.jpg

trix_lightpost.jpg


*shrug*
 
There should be less grain. Much less. I've run this batch of Tri-X through Rodinal before ( a couple rolls, actually) with less grain.
 
Stephanie Brim said:
There should be less grain. Much less. I've run this batch of Tri-X through Rodinal before ( a couple rolls, actually) with less grain.
Click to expand...

Question, is it a negativ scan or a postiv scan?

I allways see less grain from the same negativ if I print it first in darkroom and afterwards scan it with flatbed scanner.
Do I scan the negativ I have more grain in the same photo.
 
Stephanie Brim said:
Also, I scan negatives for now.
Click to expand...

So go into your darkroom and print it,
yot lose grain.
Or, try a other way in scanning the negativ.
There's so much depending on the tools of your scannersoftware.
Try to scan only the green channel, and switch on grainreduction.

Did you already told us something about your soft- and hardware?
 
Martin's observations mirror my own. I don't scan negatives any more for that reason.
Looks like Tri-x and rodinal to me. However-
You can make the grain less obvious by developing a bit longer, i.e. giving the negative more contrast. The grain doesn't seem to gain contrast as fast as the image, so when you adjust curves or select paper contrast for the image, the grain seems less contrasty.
Just my $.02.
 
Grain...

Grain...

Just throwing in some thoughts:

Abrupt temperature swings will increase the effect of grain clumping long before the emulsion starts to show reticulation, so watch your temperatures carefully.

Also, some scanners exhibit more grain when the contrast of the negative is more than the dynamic range of the scan ccd can handle. Are your negatives too contrasty?
 
Stephanie Brim said:
There should be less grain. Much less. I've run this batch of Tri-X through Rodinal before ( a couple rolls, actually) with less grain.
Click to expand...

Welcome to the unpleasant world of grain aliasing (this link to the Photoscientia website is still the most authoritative source.)

It's basically a statistical phenomenon that occurs when the (regular) spacing of the scanner pixels approaches being an even multiple of the (random) spacing of the film's grain structure. The interaction of the regular and irregular patterns causes the irregular pattern to be magnified, somewhat like the "moiré" effect you see if you lay one piece of sheer silk fabric across another piece.

The result is that a print of your scanned image will appear much grainier than a wet print of the same negative. (Printing paper is so fine-grained that for all practical purposes it produces a continuous-tone image that doesn't interact with the film's grain structure.)

The Web is full of incomplete explanations and partial "solutions" that don't really work. Anything you can do that reduces the excess graininess will also reduce the sharp appearance of the grain structure (which presumably is what you wanted, since you were using Rodinal!) There are some software solutions that may help in some cases -- I've had some success with the Noise Ninja plug-in -- but you always lose some sharpness and/or texture.

The only simple answers are to use a scanner with a pitch finer than the grain structure (some people claim the discontinued Minolta 5400 II can achieve this) or to shoot on chromogenic b&w films instead of traditional silver-based films. The chromogenic-film image is formed of soft-edged dye clouds instead of hard-edged halide grains, so it doesn't trigger the grain-aliasing response.


Having said all that, I've had some success with the following slow and irritatingly complex procedure for scanning my T-Max P3200 negatives:

-- Load the film in the scanner and set it to scan at its highest resolution (4000 ppi in the case of my sharp-but-slow Canon FS4000 scanner.)

-- Using the scanner's manual exposure controls, make a scan that's light enough to capture all the image's shadow detail. The highlights will be blown out; we'll fix that in the next step.

-- Scan again, this time using a setting that captures the highlight detail, even if this makes the midtones and shadows too dark.

-- If the negative has a really wide density range, you may need a third scan just for the midtones, although I've only encountered this situation once or twice.

-- Now, assemble all the scans as layers in one Photoshop document. You may find a different procedure makes more sense to you, but I like to put the light image on the bottom and the dark image on top, and set the dark image's transfer mode to Multiply. Then I adjust the opacity of the dark image until I have a fully-toned composite image. If the image needs "dodging" or "burning", I create layer masks to apply local corrections, duplicating the light or dark layer if necessary to add more tone in a specific area. (I know you're a Photoshop gurette, so I won't go into detail on how to do all this stuff; you also can get even fancier with problem negatives by adding adjustment layers and such for super-precise local control.)

-- Finally, to fix grain aliasing: Often the composite image will have less apparent grain without any tweaking, simply because the scanner's mechanism won't index both scans in exactly the same position; the slight difference causes a supersampling effect that breaks up the aliasing. If you want to try suppressing the grain still further, select one of the layers and use the arrow keys to move it left, right or diagonally in one-pixel increments. Often a one-pixel move in the right direction will suppress the aliasing while maintaining a natural appearance of the grain.

Good luck and have fun!
 
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The shot is overexposed. That makes things more grainy.

I try to get more grain in my shot by overdeveloping and using Rodianl but they don't look like that.

It's looks to me that the highlights are plain blown out. Try less exposure.
 
I've experienced what you did, both rodinal and diafine. In some shots, I have beautiful, soft grain, and in others, it's all nasty. I've seen the variation on the same rolls, even. Like you, I scan, and my scanning technique did not change.

I guess it is a combination of subject, tones, and exposure. For example, I find uniform sections such as sky tend to go very grainy -- not nice, but yucky.

What jlw writes makes sense, too.
 
Or, as a counterpart to nightfly's comments, perhaps it's insufficient decrease in development - ie - it's overdeveloped. Combination of the two leads to more grain. I does look a tad overexposed (250 might better), and the highlights seem to indicate that it's overdeveloped (though that might be the scan).

allan
 
My guess is the temprature of the Rodinal dillution, If your temps are too high and your time is aming for say 20°C/77F you overdevelop the negs and the Grain will look ugly....cooler temps mean longer dev. times but grain looks better imho.
If you have alot of variation on the same batch of film you should better control your development temps. (a fast digital liquid temp. sensor is in order...no slow mercury or alcohol thermometers please!)
afaik the temp of the Fix and wash aren´t that sensitive but shouldn´t be under the temperature of the Developer! (otherwise what tetrisattack described below will happen!)
 
nightfly said:
The shot is overexposed. That makes things more grainy.

I try to get more grain in my shot by overdeveloping and using Rodianl but they don't look like that.

It's looks to me that the highlights are plain blown out. Try less exposure.
Click to expand...

Exactly my thoughts. Why did you shoot Tri-X at 200 in the first place? Did you compensate for that in development time or temp? What temp and time did you develop at? Agitation regime? I'll sometimes shoot a film at 1/2 stop slower speed in high contrast situations but then cut development time by 20-30%, especially if I'm going to scan. (But not anymore, not since I ran some Tri-X at 1600 and developed in Diafine....beautiful, and very nicely controlled highlights too)

C-41 films like over-exposure and give less grain as a result, but not traditional B&W films, quite the opposite actually.
 
I'd also vote for overexposure or, more likely, overdevelopment being the cause of your excess grain. Maybe reduce your develpoment time 10-15% for EI200. I've had better results with tri-x and rodinal by using 1:100 with minmal agitation than using 1:50 with "normal" agitation.

Mark
 
JLW: thanks for that great info. If you could lead me to more information about getting good black and white scans, online or elsewhere (a good book, for instance) I would be most appreciative.
 
Well, Rodinal does generally lose you some speed, but a whole stop is a lot. Going down to 200 is pushing things (anti-pun not intended) a bit. I rate TXT at 250 in general in Rodinal. That 1/3 stop exposure difference is quite impactful.

allan
 
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