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scott jones
18-Dec-2001, 15:30
Greetings!

I have become interested in using both unsharp masking and Ross dodge/burning ma sks. I know there are several workshops, but I am interested in knowing if there are any websites or books available on learning the technique?

Also, does anyone know if there is a commercially available negative carrier wit h the proper registration aids and diffusing panels for the unsharp masking and Ross masks? Specifically I have a Saunders 4550 XLG enlarger (I don't want to co nstruct my own) Thanks!

Scott

N Dhananjay
18-Dec-2001, 15:56
The definitive reference on unsharp masking is probably the articles written by Mark Jilg and Dennis McNutt. This also includes instructions on making a registration carrier. See http://hps.vanguard.edu/Photo/Art1.html

Other folks who use masking a lot in their work and whose workshops may be useful are Howard Bond and Lynn Radeka.

Condit Mfg used to make registration equipment - Condit, alas, is out of business. They do turn up very occasionally used. Lynn Radeka advertises a masking kit at his website www.radekaphotography.com, that might be worth looking at. There is also supposed to be a new source of register equipment - an Alistair Inglass in BC, Canada. Registration equipment can be fabricated by yourself also - you will need register pins, which are available at graphic supply houses or from Bregman Manufacturing. Most register pins tend to be somewhat large (1/4" is a typical size and I've found it difficult to locate a 1/16" pin) but it is possible to improvise very workable solutions without too much trouble.

Good luck, DJ

KenM
18-Dec-2001, 16:09
Check out some of these special issues of Photo

Techniques:http://www.phototechmag.com/shop/shopdisplayproducts.asp? id=10

There are quite a few articles by Howard Bond in the magazines listed, almost all in someway related (if not dedicated) to unsharp masking.

It looks like a really cool idea, but very difficult unless you have the tools....

-klm.

james mickelson
18-Dec-2001, 20:39
Condit is no longer making registration devices. Lynn Radeka has a kit that appears to fill the bill. registering is very easy and with a little tape and a good loupe can be done adequately without any registration device other than your eye. Diffusion material can be purchased at any graphic art store or most art supply stores. It is called acetate and comes in various thicknesses with the most common being 3, 5 and 7mm. You need the 3. Or just use a cleared 4x5 piece of film as a spacer. But what you are probably going to find is that if you focus properly in the first place you don't need an "unsharp" mask. But contrast reduction masks are very useful. Go to radeka.com and email him about his kit. james

Brian Ellis
19-Dec-2001, 01:12
John Sexton includes a session on unsharp masking in his two advanced darkroom workshops. The method he teaches is much simpler than that taught by Howard Bond and seems to work well. I don't believe that the utility of unsharp masking has anything to do with how you focus. Also, you actually don't need any spacer material. The thickness of the film alone will create enough space to make the mask unsharp. work. At least this is what Howard Bond concluded in the second of his "Photo Techniques" articles on unsharp masking. I always found the spacer to be a pain - dust, scratches, etc. appeared on it with regularity. Since Howard's second article appeared I've stopped using a spacer and the unsharp masks seem fine without it.

KenM
20-Dec-2001, 11:34
I don't really have anything futher to add, but I do have a question about unsharp masking. After responding above, I decided to actually give masking a try.

I made a negative mask, registered it with the original on my light table, and taped them together as best I could. I can certainly see how pin registration might be useful :-)

My enlarger is a 4500-II, and all my negative carriers are glassless. What I noticed is that when I put the sandwich in the carrier, it seemed that there was an airspace between the two negatives, which is not what you want, since the mask becomes incredibly unsharp.

Are people using glass carriers when doing masking? Or, are people exposing masks through the anti-halation layer, and then sandwiching the negatives together so the emulsions are facing in the same direction?

Thanks!

-klm.

Mark Gilles
20-Dec-2001, 15:22
Scott,

I suggest that you take a look at the services provided by Lightbox Inc. Bruce did a splendid unsharp mask for one of my 4x5's. My experience with them was very positive and I feel they take a great deal of pride in their work. Bruce has taken the Howard Bond workshop and they even have a gallery of Bond's work up. Best of all, the price was very resonable -$40 for the completed mask. I am not affiliated with them in any way, I'm just a happy customer. Here is a link to their site, click on fine art services. Cheers!

http://www.lightboxinc.com/home.html

Dr. Dan
20-Dec-2001, 16:02
Ken,

My experience parallels yours. I have made beautiful 8x10 contact prints with unsharp masks but my every attempt using 4x5 film, in my LPL 4500 / glassless carrier, in a word; sucks. I've wondered if it was the enlargement process itself. Maybe my 8x10 masked negs wouldn't look so good either if enlarged (but they seem very sharp on the contact print). I hadn't thought about trying a glass negative carrier. Anybody out there who can share thir expertise?

Robert A. Zeichner
20-Dec-2001, 18:23
For an unsharp mask to work, it must be sandwiched with the negative between pieces of glass. Simplest arrangement would have the emulsion of the mask contacting the base of the negative, which is how the mask was exposed in the first place. Any spacers used would go between the two pieces of film. Without glass though, there is no way you can get perfect results as the mask will be so far out of focus it will be out of register and too diffuse.

james mickelson
22-Dec-2001, 12:30
Again let me restate my view that if you focus properly in the first place, corner to corner, and you use the proper exposure/develoment techniques along with the proper film/ developer combinations, you don't need an unsharp mask to get an incredibly sharp print. And this is brought out by the fact that you need look no further than John Sexton, Howard Bond(pre mask), Bruce Barnbaum, Ray McSaveney and any number of other 4x5 photographers. That isn't to be construed as suggesting unsharp masking hasn't a place in the tool kit. I have been using it for certain negatives for years now. And yes you do need to work with a glass neg carrier. Yes you can get away with using only the thickness of the film instead of a spacer.......some of the time. That depends on what the mask is for and how unsharp it needs to be. There are many times you need more or less unsharpness than that provided by the thickness of the negative. And the technique is better used, and named, contrast control mask. That is it's main purpose. To control the internal contrast of the negative. That's why the print appears sharper. Or have I miscontrued Howards original premise. It was used for decades in printing. It ain't new. And it doesn't require an expensive set up. It makes things easier if you have a punch and registered neg carrier but it ain't necassary. James