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Randy Redford
19-Jul-2004, 12:27
I am looking for a good BW film for my 8x10 to scan for large digital prints. Any suggestions? Looking for minimum grain, so thought either T-Max or FP4. Any suggestions would be greatly appreciated. Thanks.

David A. Goldfarb
19-Jul-2004, 13:03
I find that the scanner (I have an Agfa Duoscan) likes a thinner neg than I would normally want for conventional printing, but if you have a newer scanner with a higher Dmax, you might be able to get away with a different film. TMax 100 in D-76 (1+1) scans well. Tri-X in Acufine scans better than Tri-X in PMK. In general I find PMK negs harder to scan. FP4 is probably a good choice, maybe with a bit less development then you might normall use.

Whatever you do, you might try a test where you shoot three or four negs of a scene with a full range of tones, develop for a range of processing times (maybe normal, 15% over, 15% and 30% under), and see which produces the best result on your scanner.

Ken Lee
19-Jul-2004, 14:53
What David said.

One can always add contrast to a soft negative, but you can't add detail to the shadows or highlights, once they exceed the range of the scanner - unless you want to scan twice or more: once for the low values, another time for the high values, etc. That gets tedious.

Just make sure that the scanner software is not performing any clipping of values, automatically on its own. You want to record everything on the film. You can always adjust later in your editing software.

Ralph Barker
19-Jul-2004, 15:33
I think part of the question, Randy is how large is "large" when you speak of digital prints. Then, what is the "sweet spot" resolution-wise (output DPI) for the types of digital prints you're looking at making. Assuming that you can get by with even 300 DPI at the print size you want, you'll likely be working with fairly large files - around 216MB for a 16-bit 30x40 at 300 DPI, for example. That can be a limiting factor for layering or other complex digital manipulation, unless you have a computer with a gigabyte or more of RAM. (Remember, Photoshop wants 3x or 4x the size of the file in useable RAM. Even then, large operations will be slow.)

But, a 30x40 is only about a 4x enlargement from 8x10, so grain is less of an issue than one might think. I'd lean toward using a film that satisfies the pictorial requirements first, and then fine-tune exposure and processing for optimal scanning. (I, too, agree with David's observations in that regard.) That said, I like the creamy look of FP4+ when scanned, but HP5+ scans nicely, too.

Bruce Watson
19-Jul-2004, 16:54
I drum scan Tri-X at about 11x which lets me make 40x50 inch prints without any problems. Prints that size are virtually grainless. Unless you plan on printing larger than 80x100 inch prints, grain should be the least of your worries.

Tri-X scans well and has that classic Tri-X look. FP4+ should be even easier to scan if that's possible, and like Ralph says, it does that "creamy look" really well.

Basically, I think you'll find it hard to go wrong. Pick a film that gives you the look you want. Scanning shouldn't be difficult for any of the B&W negative films. Process the film as if you were going to print in the darkroom and you should be fine.

tim atherton
19-Jul-2004, 17:49
Hogarth, what's you favourite Tri-X soup that seems to combine well with scanning?

(I'm finding HP5 and DD-X works very well, with lovely scans from 8x10 - also just trying some Paterson stuff F50? can't remember offhand) - niot much grain showing onthe big prints I've done

Ken Lee
20-Jul-2004, 05:36
I suggest TMax 400 developed in Pyrocat HD. The film speed is 320 or 400, and the negatives have a delightfully long range. They are suitable for scanning, printing via silver, and via platinum. Since Pyro developers are compensating, shaow values get "extra" development. Thanks to Sandy King for this combo.



You can view an example of excellent highlight separation and shadow values here (http://www.kenleegallery.com/f300a.htm" target="_blank)

steve simmons
20-Jul-2004, 07:05
I suggest TMax 400 developed in Pyrocat HD. The film speed is 320 or 400, and the negatives have a delightfully long range. They are suitable for scanning, printing via silver, and via platinum. Since Pyro developers are compensating, shaow values get "extra" development. Thanks to Sandy King for this combo. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I compared HD with PMK n the current issue of View Camera and found the following differences

1. PMK gave me better shadow detail when the two negs were exposed at the same EI (Tri-X and FP4+were the test films).

2. The high values on the PMK neg were higher on the scale than the high values from the HD neg. Simply extending the develping time with the HD neg woud not have changed this. I think this is/was a function that the PMK neg had more stain which is proportional to the silver density and thus greater in the high values. This greater proportional stain with the PMK neg seemed to lift the high values

3. The PMK neg was slightly granier but also a little sharper.

I have been scanning PMK negs for several years without any problem. I develop my negs the same for traditional printing and scanning. By doing so I can go either way and I do not have to decide ahead of time.

Samples are in the July/August 04 issue. Later this summer I will place more side by side examples on our web page.

steve simmons www.viewcamra.com

Bruce Watson
20-Jul-2004, 07:15
Tim,

I'm using XTOL 1:3 in a Jobo 3010 drum on a CPP2. In comparison to HC110-H, the grain is a bit smaller and I like the structure a bit better, and the overall result seems to be a bit sharper. Of course, YMMV.

Paul Butzi
20-Jul-2004, 09:56
Chuck Downs and I did some very limited testing of how different film/developer combinations scan.

We've tested TMX in Tmax-RS 1+9, XTOL straight and 1+3, and in a divided pyrocatechol formula which Denny Wagner was kind enough to send me.

The best looking scans in terms of apparent resolution (not sharpness), grain and other noise, etc. was the Pyrocatechol developer. XTOL 1+3was a close runner up, followed by XTOL straight, and then Tmax-RS 1+9 trailing way behind.

This was a bit of a surprise since back when I tested Tmax-RS and XTOL for silver printing, I felt they were very, very close, switched to XTOL, then switched back because of the convenience of Tmax-RS.

From scanning older negatives, I'd say that D-76 1+1 is also an excellent choice, right in there with the Pyrocatechol developer and with XTOL 1+3.

A friend has pointed out that of these results, the best scans are coming from those negatives with the longest development times, and the worst scans from those with the shortest development times. I would hesitate to give this any label beyond rank superstition based on such a small sample but it would be interesting to hear other folks observations on this.

Bruce Watson
20-Jul-2004, 10:51
Paul,

Hmmmm..... interesting observation your friend made.

What I remember is that, everything being equal (which almost never happens, but still), longer times in the developer tend to increase grain size. Which should make scanning a little worse.

On the other hand, longer development times are often caused by dilution of the developer (XTOL going to 1:3) which effectively lowers the amount of sulfite in solution, which also makes grain a little larger, but also a little sharper. Which could make scanning a little better.

Interesting observation indeed. It will take some exacting experiments, developing negatives to the same CI in different developers, using the correct EI for the film in the developer under test, to really learn the truth. Makes me wish I worked in a lab that had the capabilities. Or at least makes me want to read the results of the experiment if someone else runs it ;-)