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ignatiusjk
9-Jun-2010, 18:21
Does anyone have a good method for improving the resolution on 4x5 B&W negs? My sharpness is there I'm just missing that grain free print that a 4x5 neg gives you.I've had some negs that give that"grain free" look but it's not consistant enough.I also have the disadvantage of having to send out my film for processing. I use Ilford Delta and the lab uses Ilford ID11 developer.Any thoughts.I rate the film at 100 iso and my negs have good density to them.

Gem Singer
9-Jun-2010, 18:35
I'm surprised that you found a lab. that still develops B&W film.

I suggest that you develop your negatives in Pyrocat-HD. Do them yourself.

And switch to Ilford FP-4+ film.

ic-racer
9-Jun-2010, 22:11
If you shoot at f22, then your max resolution is going to be somewhere around 60-70 line pairs per mm at the very best. That will likely be way less resolution than the film resolution, no mater how poorly they process it.

I'd bark up a different tree :)

Bruce Watson
10-Jun-2010, 04:26
You're seeing grain in prints? How big a print are we talking about here? From properly processed (Dmax less than say 1.5) Delta 100, you should easily be able to make a "grain free" enlargement in the 6-8x range, perhaps bigger. So how big a print are we talking about?

ic-racer
10-Jun-2010, 06:20
BTW grain and resolution kind of go together. The less-grainy developers smooth the edges of the grain clumps and impair resolution.

nolindan
10-Jun-2010, 07:50
BTW grain and resolution kind of go together. The less-grainy developers smooth the edges of the grain clumps and impair resolution.

Funny, my experience photographing test targets is just the opposite: fine grain developers such as Microdol allow more resolution than 'acutance' developers like Rodinal.

It is a difference between perceived detail and real detail. Rodinal is great at making it look like there is lots of sharp detail in the print but it is illusory as the large (though sharply defined) grain and "edge effects" can only create artifacts that obscure the real detail. Unsharp masking, the ultimate in edge effects, produces the effect of extra detail, but the actuality of the process is that it removes information from the image.

It isn't that Microdol "smooths away" detail, my understanding of the action of the S. Chloride is that it keeps grain clumps from forming when an exposed halide crystal would otherwise cause an adjacent unexposed halide crystal to develop. There is misconception that Microdol is a 'high solvent' developer, it isn't - it has the same quantity of S. Sulfite in it as D-76/D-23.

One method of evaluating a film/developer combination's granularity is to measure the decrease in resolution due to large grain size.

Ref. Mees et. al. Theory of the Photogaphic Process, revised ed., Ch 24 The structure of the developed image.

ignatiusjk
10-Jun-2010, 17:00
You're seeing grain in prints? How big a print are we talking about here? From properly processed (Dmax less than say 1.5) Delta 100, you should easily be able to make a "grain free" enlargement in the 6-8x range, perhaps bigger. So how big a print are we talking about?

16x20 on a Epson 3800 printer.

Nathan Potter
10-Jun-2010, 19:25
My experience matches that of Nickolas. I used to use Microdol X with Panatomic X and under 5X mag. prints were essentially grainless for normal type development. Don't know about using Microdol with Ilford Delta though. I think you're in a world of hurt if you send out your film - there is simply little or no control over the negative process.

Nate Potter, Austin TX.

Bruce Watson
11-Jun-2010, 06:23
16x20 on a Epson 3800 printer.

Ah. And how was the film scanned? The reason I ask is this sounds like possible grain aliasing from scanning. A 4x enlargement from any modern film should be nearly grainless unless something is seriously or intentionally wrong. But some scanners exaggerate the heck out of silver grain clumps. Has to do with the pitch of the photoreceptor sites matching up with the average grain clump size and distribution -- you get the optical equivalent of a beat frequency. Sometimes described as "pepper grain".

Henry Ambrose
11-Jun-2010, 08:20
I second what Bruce wrote.

I don't think anyone can mess up 4x5 Delta 100 badly enough to get any visible grain at that reproduction size.

Ron Marshall
11-Jun-2010, 08:39
I also agree with Bruce; at certain settings my Epson 4990 emphasizes grain.

ic-racer
11-Jun-2010, 09:03
It isn't that Microdol "smooths away" detail, my understanding of the action of the S. Chloride is that it keeps grain clumps from forming when an exposed halide crystal would otherwise cause an adjacent unexposed halide crystal to develop. There is misconception that Microdol is a 'high solvent' developer, it isn't - it has the same quantity of S. Sulfite in it as D-76/D-23.

Thanks for clearing that up. I used to use Microdol-x in high school, but I just remember the images as 'mushy' so I have pretty subjective recollection of it :)

BTW do you know of a good link to MTF data for films?

Ron Marshall
11-Jun-2010, 09:08
http://www.kodak.com/global/en/professional/products/chemistry/bwFilmProcessing/selecting.jhtml?pq-path=14053

Xtol is the sharpest from Kodak.

stevebrot
11-Jun-2010, 11:49
I also agree with Bruce; at certain settings my Epson 4990 emphasizes grain.

Another voice added to the chorus...

Steve

(What scans as grain usually is not truly grain...)

Ken Lee
11-Jun-2010, 12:52
Will oversampling ameliorate it ?

Henry Ambrose
11-Jun-2010, 13:58
Will oversampling ameliorate it ?

It might, or use a little blur and then USM - if the sky shows some grain select the sky and do a little blur work on the selection (likely won't need to sharpen the sky - right?). Or maybe blur the whole file and then sharpen. Experiment with USM settings.

Part of this depends on the printer. You might see some grain at 100% on screen but it may not even show when printed on any particular printer.

I'd scan at full hardware resolution and then sample down at printing if need be. I'd also turn off any and all sharpening in the scanner controls. Scan in 16 bit. The other (I hope obvious) part is to be sure to feed the scanner something it likes. Do the problems show up on some negs and not others? Do "perfect" negs show the problem? Are you whacking out the scanner controls to get a decent scan? If so, change that. A neg that the scanner likes will scan easy-peasy.


You can solve this problem with certainty by printing in a real darkroom the way you're supposed to.

<just a little friendly poke don't get offended, anyone>

Nathan Potter
11-Jun-2010, 15:19
Well, I assumed the OP doing silver prints in a darkroom. It's inconceivable that anyone would inkjet print a fine negative. But if inkjet was the case certainly Bruce's comment about a near match between the period of the film grain to the scanner pixel or printer SPI could yield a pseudo grain effect from interference, a sort of moire pattern, which when suitably sharpened could look like coarse grain. I'd check the scan on the monitor at various magnifications and look for an anomalous grain effect. Yes, changing the SPI of the scanner should alter the effect unless it is real grain in the neg. or a printer artifact.

Nate Potter, Austin TX.

Robert Hughes
14-Jun-2010, 11:39
You can solve this problem with certainty by printing in a real darkroom the way you're supposed to.
Assuming you have a real darkroom inside your computer. Hey, it IS pretty dark in there... there's a couple glowing LED's but they're red, so won't affect the prints.

It's inconceivable that anyone would inkjet print a fine negative.
That is so cute!

It's inconceivable that anyone would drink beer out of a wine glass. Unless they did...

Lenny Eiger
14-Jun-2010, 12:20
Delta is a terrific film. It's sharp as a razor, a tiny, and likely imperceptible bit sharper that TMax 100, in fact. Grain is plenty tight. It has all the sensitivity of all the films. Whoever said switch to FP4, well, probably shouldn't suggest this - it isn't as good.

I'm with Bruce on this one. Either you are over-developing it to cause this grainy effect (easy to do in Xtol) or you are scanning incorrectly.

Lenny

Martin Aislabie
18-Jun-2010, 16:08
I second what Bruce wrote.

I don't think anyone can mess up 4x5 Delta 100 badly enough to get any visible grain at that reproduction size.

If the processor had given the film a major thermal shock they might have induced reticulation - which many (wrongly) assume is grain

Just a thought :confused:

Martin

Robert Hughes
19-Jun-2010, 11:30
If the processor had given the film a major thermal shock they might have induced reticulation - which many (wrongly) assume is grain

In the Good Old Days, fine art painters would intentionally work with materials that would crack and reticulate as they dried and aged. It was considered part of the look for the finished work.

Nathan Potter
19-Jun-2010, 12:49
Excellent Robert! I say I don't care what I do to modify or even savage a print as long as the effect helps articulate what I want to say about the print. If I need to smear the emulsion, reticulate the neg, accentuate grain, cut the print into pieces and rearrange, even inkjet print, I don't really care as long as I accomplish my objective and convey my vision. I think all fine artists have employed novel techniques in their work and I'd cite the image manipulation of Picasso as an example.

Nate Potter, Austin TX.