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Edward Pierce
25-Feb-2023, 14:12
Anyone have an f/stop printing chart in pdf format you’re willing to share?

MartyNL
25-Feb-2023, 14:42
Here you go. I find it best printed at A3 size for in the darkroom.

Edward Pierce
26-Feb-2023, 06:02
Here you go. I find it best printed at A3 size for in the darkroom.

Got it, thanks

ic-racer
26-Feb-2023, 07:30
If you have a calculator you don't need the chart:
1 stop = x 2 or /2
1/2 stop = x 1.4 or /1.4
1/3 stop = x 1.26 or /1.26
1/4 stop = x 1.19 or /1.19

nolindan
26-Feb-2023, 10:40
Google sez:

https://www.tmax100.com/photo/pdf/fstoptiming.pdf
https://www.speedytemplate.com/f-stop-timing-table.asp

I've heard rumours of timers that will do it all for you...

Doremus Scudder
26-Feb-2023, 12:39
If you have a calculator you don't need the chart:
1 stop = x 2 or /2
1/2 stop = x 1.4 or /1.4
1/3 stop = x 1.26 or /1.26
1/4 stop = x 1.19 or /1.19

Gee whiz... I use percentages instead of f-stop timing and don't even need a calculator. It's pretty easy to figure 10% of a base exposure time; that's just a bit less than 1/6-stop. 25% is 1/3-stop, 40% is 1/2-stop, 60% is 2/3 stop and 100% is a full stop, approximately, of course, but the percentage increments are just as flexible as f-stop increments.

The above list is for burning (adding exposure), of course. For dodging, it's just as simple. You could work out the percentages to correspond to f-stop increments if you like, but using a simple percentage of the base exposure works just as well, even if the increments don't align so neatly with f-stops.

The thing is, once you get an idea of how much change a certain percentage makes, using percentages works just as repeatedly and in equally-predictable increments as f-stop timing, just without that pesky square root of 2 :)

Doremus

Jason Greenberg Motamedi
26-Feb-2023, 12:55
There is a free app (f-stop printing calculator) that works well enough, but is limited to 3/4, 1/2, and 1/4 stop

MartyNL
26-Feb-2023, 16:38
As far as Apps go, the film and darkroom, FADU f-stop enlarger timer App, works a treat. :)

Bob Wagner
3-Mar-2023, 07:28
If you use a Gralab clock face timer (Can't remember the model number, but the one that's been around forever) Lambrecht has a template that lays on top of the dial and shows f stop increments, very handy - used it for years. Eventually bought a Darkroom Automation f stop timer - greatest thing since sliced bread