Recent content by jisner

Dektronics just announced that their budget-friendly UV/Vis densitometer is now shipping. It measures film transmission density using either UV or ortho light, as well as reflection density. I've had one for several months and find it superior in many ways to my XRite 361T. The Dektronics is...

Hi Byron, BTNS is available, but only on a one-on-one basis. I share the software and book freely with anyone who is willing to work with me through their first calibration, typically over zoom. I have been working this way for at least three years, and currently have two students. Here's a...

Sorry, I must have deleted it. Here are two new links: documentation Excel workbook

Since my last post, I have tried many of the suggestions given by you and others, focusing mainly on humidity. I'm convinced that humidity, although it is a good idea, is not what's preventing my prints from becoming fully toned. I made a series of 4x5 prints on HPR using a Stouffer TP4X5-31...

Ah, now I understand. I clear the prints within five minutes of exposure, but as I said earlier, the prints are bone dry during exposure. When I read Sandy King's article, I missed the following: "Vandyke, like kallitype and platinum/palladium, gives richer tones if coating and drying is...

What you say about incomplete toning is very interesting. In Sandy King's GTV article (which I follow), he says "Rinse the print in running water for about a minute after development, then tone.... It is recommended that the gold thiourea toner be used one-shot and discarded after use. Toning...

I don't understand why humidity during exposure should make a difference, since I tone the print in the darkroom after clearing and before fixing. It seems like humidity during exposure would only alter the toning if there was gold in the sensitizer. I hadn't realized that this was another...

The consensus here seems to be that gold toning does not impart a warm hue, which runs counter to my experience with gold thiourea toning, which imparts a pink / warm taupe tone that I find objectionable, particularly in the highlights. The only reason I was considering switching to platinum was...

The humidity in my "studio" is currently 24%, and that's with a humidifier running. I don't humidify the paper prior to coating or exposure, and never have done so. In spite of this, my gold thiourea-toned vandykes are pinkish, and that's what I have been calling warm. It's certainly warmer...

As you say, "[toning] will more or less evenly attack the material it has access to. But because there is just much less material in an absolute sense in the upper part of the tonal scale, you generally see a bigger proportional change in that part of the scale as things progress." It seems so...

Thanks for your suggestions. I make 1000 ml of gold toner following Sandy's receipe, use 30-40 ml for each 8x10 print, then discard it after use. I have been doing this even if I'm making more than one print, which is perhaps wasteful. I'm glad you confirm that platinum, like gold, tones from...

I have been making gold thiourea-toned vandyke prints following the instructions in Sandy King's Unblinking Eye article, and have gotten good results. Now I want to try platinum toning for a more neutral tone. First question: In the toning step of Sandy's workflow, can I simply substitute...

Lamp Designer (LD) is a tool you can use to analyze your current exposure unit or spec out a replacement unit. Here is a document that describes it. LD is concerned with the effect of nonuniform exposure on alt process prints. Non-uniform exposure may not be a serious problem in general...

BTNS is not an acronym! Now you know.

One year ago today, I posted to this group an offer to share BTNS with any brave soul willing to try a completely new way of calibrating digital negatives. Unlike other calibration methods, BTNS is based on a mathematical model of tone reproduction. I began work on BTNS nearly five years ago in...