F stop timer

[Cor]

Funny, I just re-read this and it is quite an understatement.

I'd say it is a fatal flaw in f/stop timer logic.

If there could be a timer that marks time in terms of noticeable tone change and this time would vary depending on paper grade -- now that would be awesome.

Meanwhile, I will stick to 1/3 stop and Grade 2.

I fail to see the fatal flaw, a lower grade (say grade 1) by definition a longer contrast range than a higher grade (4), so it takes more stops (time units) to go from white to black. If your f stop timer can handle it (mine cannot, it's "only" 1/4 stop steps) you would use 1/12 steps at Grade 5 and perhaps 1/3 steps at Grade 0, what is the problem?

Best,

Cor

[GeorgesGiralt]

Hello Bill,
I own and use a marvelous piece of gear : the Analyser Pro from RH Designs.
It does just that. It knows the sensitivity and contrast range of the paper you put on your easel, and it shows you, on a grey scale, what gray tones you will get when committing a print. whatever grade you choose... you can figure what your print will look like on different papers without actually printing it...
Not cheap but pays for itself in less time than you thought it will...
If you're short on money don't try one !
P.S. Gene Nocon, the one who devised F stop printing and was a hell of a printer has just passed away. RIP.

[David Aimone]

I love mine. The only "new" piece of equipment in my new darkroom and it is worth every penny!

[Bill Burk]

what is the problem?

No real problem, just have to mentally shift into lower gear on steeper grades.

Sorry to hear of Gene Nocon's passing, I just saw his video.

I work on Grade 2 most of the time and when I saw the video I thought how lucky I was to have always used his concept of the f/stop time series.

But I was caught off-guard when doing a stylized Grade 4 print and a 1/3 f/stop burn took my sky from stark white to moody storm.

[blevblev]

I use an RH Design f-stop timer as well. The authors of "Way Beyond Monochrome" suggest that you should make prints in a kind of flip side of the axiom used when making negatives - "expose for the shadows and develop for the highlights." That is, "expose for the highlights and control the shadows with contrast." So, make a test strip and ignore everything except the highlights. Pick the exposure time/f stop that gives correct highlights. Then make a test print and evaluate the shadows. Change the contrast to control the shadows. Just as changing negative development time will only minimally change the shadow ares in a negative, changing print contrast will only minimally change the highlight areas of the print. After that, dodge and burn if necessary.

The F-Stop timer particularly makes your test strips more meaningful. Then after you determine the exposure you want from the test strip, you simply start with the base exposure of the test strip, and press the up button the number of times that corresponds to the number of sections of the strip that matches the exposure you want. In other words, if your test strip shows that the 5th strip is the exposure you want, you start with the base exposure, and hit the up button 5 times. This will give you the exposure of the 5th strip.