F stop timer

[Pawlowski6132]

Does anyone use one of these? I'd be curious to know how you use it.

Thanx

[Peter De Smidt]

I use an f-stop professional by RH Designs.

First, I make an educated guess about what overall contrast the print should have. Second, I use the timers' test strip function. You can have it space the steps by whatever increments you like. 1/12th stop, 1/6th stop, 1/3 stop... In general, with lower contrast it's better to uses bigger steps than with high contrast. Third, I now make a print at the exposure that the test strip indicated would give the best overall highlight exposure. Process, wash a bit, dry, evaluate. If the contrast is off by a bit, I adjust. (I use a settings on my De Vere color head to change contrast. I tested so that I can change contrast while keeping Print Value VIII constant.) Fourth, I may make minor changes to exposure, and then I work out a pattern of burning in areas. It's easy to program the time to give a base exposure and up to 10 separate burning steps. These are entered as fractions of an f-stop. E.g. I can specify that I want to burn down the sky by 1/2 stop more exposure than the main exposure. If I change my main exposure, all the burning steps will be recalculated to the required amount of more exposure.

This timer is the best piece of darkroom kit that I've ever acquired.

[banjo]

you can make your own !!
http://www.darkroomagic.com/DarkroomMagic/Darkroom.html

[jeroldharter]

Ditto Peter's comments.

[Bill Burk]

I marked my timer in 1/3 f/stop increments. It serves me well. But I only recently realized that it is suitable for work in a single grade (for example Grade 2) but as you move up grades, the increments cause greater change. So something more sophisticated is required (if you are going to use random Grades of paper).

[kev curry]

As Peter said; plus the timer mentioned has two separate programmable channels that make split grade printing easy. The timer has made my D/R experience more controlled and enjoyable, but I'm also aware that some master printers use nothing but a simple metronome and I'm beginning to understand its benefits over any timer.

[bigdog]

I'd be curious to know how you use it.

I use it essentially the same as any other enlarger timer. Except, that it is more intuitive to look at a test print and determine that it needs another half stop, than that it needs X more seconds. Also, test strips made in f stop incriments have been a revelation.

[Richard Rankin]

I used to own one in Australia, and felt it was one of the most valuable pieces of equipment I had ever purchased. If I ever have the money to do a decent darkroom again, that will be my first purchase.

Richard

[polyglot]

a spot of devil's advocacy

[Bill Burk]

In general, with lower contrast it's better to uses bigger steps than with high contrast..

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.