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Saulius
12-Feb-2006, 12:41
I need a little advice from those who work with drum scanned images. I normally do my own scanning of 4x5 trannies and B&W negatives on my flatbed Epson 4870. I had a few 8x10 B&W negatives scanned along with a couple 35mm color transparencies. I’ve heard that you will see the grain of the film in the scan but I wasn’t expecting to see so much. It is especially noticeable and undesirable in the white portions of the images and the sky. I sent these out to Westcoast Imaging who seem like quite a reputable place and they do not sharpen the images during the scan. So I am assuming what I see is normal on drum scanned images. If this is so do I need to do anything special when working them in Photoshop? That is do I need to work those areas like white highlights and sky portions of the images to reduce the grain so it won’t show up in the print or do I just work as usual and not worry about it? If I need to work those portions of the images how do you go about it? Any tips or advice is much appreciated. Thanks.

Jerry Fusselman
12-Feb-2006, 12:58
Very early in your workflow, perhaps the first thing, convert to Photoshop's LAB colorspace and blur the A and B channels. Blur both channels separately. The surface blur filter is likely to work best if you have CS2, but gaussian or dust and scratches are other contenders. You should usually blur the B channel more. This is covered in Dan Margulis's lastest book.

Bruce Watson
12-Feb-2006, 14:00
Which film is giving you problems? How much enlargement in the scan? What are you doing when you "see so much" grain? Are you looking at prints made from the scans?

Else, if you are trying to judge graininess from a photoshop view, don't. You can't get an accurate idea of graininess in your file from photoshop. Even at "100% pixels" you are looking at quite an enlargement. This is due to the difference between the output resolution of your printer (say, 360 dpi for an Epson 7xxx or 9xxx, 305 dpi for some Lightjets and Chromiras, etc.) vs. the realtively smaller resolution of your monitor (typically less than 100 dpi, often the "standard" 72 dpi). This printer-vs-monitor issue can easily be a 5x enlargement all by itself. IOW, the graininess you see at "100% pixels" won't be visible in the print.

But to answer your question directly, drum scans are not inherently grainy. They are typically considerably sharper than CCD scans however, and the softer scans from a CCD scanner can obscure the graininess of the film.

I've been a drum scanner operator for years now, and scan primarily negatives (B&W and color). If you know what you are doing and have software that is "negative friendly" then it's not a problem drum scanning negatives. I get seriously good, sharp, small grained scans to the point where I can print 10x enlargements (125 x 100 cm prints) from 5x4 Tri-X that are visually grainless. Same for 160PortraVC. I don't start to see grain in prints from 160Portra until I get to 12x enlargement (from a 5x4 negative, that's about 150 cm long).

That said, graininess is a function of density. With negatives, your highest density is in the highlights, like your clouds. So clouds should be more grainy than shadows in prints from negatives. If this bothers you, consider using tranny film - where the highest density part of the film is the shadows, where it's difficult to see the graininess.

Henry Ambrose
12-Feb-2006, 17:06
What Bruce wrote!

Seeing well resolved grain on screen is a good thing and it won't show up until huge enlargements that you'd have to stand so far back from to view you would not see the grain, especially with larger film sizes. In any event grain is part of the film, its what makes the image - its supposed to be there. As noise or texture in the file it can make for smoother looking transitions and especially in big solids areas like skies it can hide most banding that might occur.

I just did a comparison of a 4990 scan to the same frame drum scanned (6x7 Reala). I see nice sharp grain in the drum scan and barely in the 20x24 print. But I have to get really close to the print and look for it. Thats about a 10-12x enlargement - if not more as the frame is cropped a good bit.

If you made a darkroom print of similar magnification you'd love it if you had good sharp grain across the frame, wouldn't you? It'd be a sign that your gear was up to the task and well tuned.

Jerry Fusselman
12-Feb-2006, 21:21
So Bruce and Henry, do you completely reject the notion that using Photoshop to remove grain from scanned film can help the final output?

Apparently, there are three possible reactions to grain---one camp wants it and may even try to increase it, the second camp thinks grain is okay or needed or nobody minds it, and the third is that it is bad and sometimes worthwhile to take steps to counter it. Sounds to me like you two are in the second camp, but some of us are in the third. Did I read you wrong?

I might be in the third camp, in part, because I reject the notion of standard viewing distances trumping all. I like to get up close to big prints and enjoy the detail here and there.

Henry Ambrose
13-Feb-2006, 06:37
Jerry,

Of course I'm writing only for myself. Your preferences are yours and I can't argue with them and don't want to! If your methods make prints that you like better then they must be right for you.

I don't see that grain obscures fine detail. I do see it as part of the structure of the picture and I think it helps avoid the plasticy digital look. If we were talking about big oatmeal looking grain aliasing then thats a different problem and probably needs to be dealt with in some manner (like re-scanning). In general I say the less post processing the better.

Since this is a large format forum I answered in respect to the Saulius' 8x10 negatives and grain. By the time grain becomes an issue the print will be huge and I'd be standing back far enough that I would not see grain. Or I might get close and see some grain that I'd simply accept. His 35mm scans would likely be a different case but ya know they'll look like 35mm no matter what you do in post processing. My answer is to print them at a size that compliments the quality that is there and if the grain (or whatever) starts to offend then its time (or past time) to stop.

And to answer your question whether I reject using PS to remove grain, I reject it on the same grounds I reject ICE - it is IMO unneccessary and destructive post processing. Especially with a great drum scan why resort to heroics to "improve" on whats really there in the film?

Bruce Watson
13-Feb-2006, 15:56
Jerry,

No, I don't reject the notion of reducing or modifying grain to lessen it's appearance. I'd use a program like NeatImage or NoiseNinja if I were going that route.

In fact, what I did was move up in format. My 5x4 film does an excellent job for me - and allows me to make huge prints when I want. Grain is really a non-issue for me. So I've never felt the need to use a program like NoiseNinja or NeatImage. I'm just sayin'...

Saulius
13-Feb-2006, 17:44
Thanks for the responses. I guess I'll just first try printing using my usual workflow and if there is excessive grain in the print then I'll try to find a way to work around that. Never having had drum scans done before the amount of grain in the images, especially as you zoom in Photoshop was much more then I've been accustomed to. The grain in the 35mm threw me but I guess I am just used to looking at LF scans, never having scanned 35mm before.