A friend of mine just presented me with this little semi-transparent disc complete with instructions. Looks like it would cut down on the guesswork when printing. Has anyone ever used one with good results?

I've used on off and on for years. It will get you to the ballpark, IF it's placed in the right part of the image. That's the trick. (and I can't explain it ...)

Try it and see. Don't waste larger sheets of paper. Cut to 4x5 and give it a go.

David

I used one years ago and probably still have it somewhere. They are somewhat useful since you only need make one exposure. Still they are not as useful as a well trained eye.

i have used mine consistently for the past 20+ years. it is good for getting you in the ball park, but as a previous poster said, you have to position it in the place you consider the most imortant part of the neg. position it on your easel while projecting your image, slip your test paper underneath, set your timer for one minute. expose, then develop normally. take dry down into consideration if viewing wet.
jim

I have used these for many years rather than step wedges, etc. I generally use two, placing one on a highlight area and the other shadow a area. It is only my first step, after that I make small test patches (without the tool) for the same areas until I get the exposures I want in those areas, increasing to larger test strips and or prints before making final test prints and such.

I've got one, and learned using one. But I don't care for it anymore and just use test strips.

First of all, you have to expose for a full minute. That's an eternity of exposure to my internal clock.

Second, it can't show the full image in the little pie shaped windows.

I bought an Omega Print & Repeat easel, and intend to try it for exposure tests. Get 8, 2x3 images of the same part of the image on one 8x10 so you can really see the effect of the different exposure. At least, I hope so.

Charlie

I just skip the whole thing and go and make full size test prints. I can usualy nail it by the third sheet. This is more about knowing your materials and where you want go than anything else. For a really good description check out Bruce Barnbaums book-and don't be a darkroom wimp! Those strips don't really tell you anything especilly if a highlite or dark section is not on the right strip. Try it-you might see what a difference it makes.
Best,Peter

If you are trying a new paper, or experimenting with a realy large enlargement, a test using this scale of an enlargement of a test negative, or even a piece of unexposed but developed film, can serve the same sort of purpose as an enlarging meter - i.e. it can get you into the ballpark before you do the fine adjustment test strips that help you refine your print.

Essentially, it provides a reference, and a useful initial guide.

I used one and still have them on hand the ability to assess the highlight and shadow area by using 2 off them is valuable,to my mind they can take the variables in mono printing say dev that getting on the scale will quickly get you around the mark.
have not used them since I purchased the analyser pro 500 from RHDesign this analyser is awsome.
regards
Barry Treleaven