F-Stop printing treats the paper exposure in the same way as exposure with the camera is treated ie in f stops rather than pure linear times e.g. shutter speeds going up in a non-linear sequence - 1 second, 2 sec 4 sec 8 sec 16 sec rather than 1sec, 2 sec, 3 sec, 4 sec etc. This does seem to be a natural way to deal with the darkroom exposure.
I have only recently bought an RH Designs Stopclock Professional, having previously done the mathematical calcualtions in my head/bit of paper for F-Stop printing - it is best not to actually think of times with the timer but densities. If a print looks too light by say half a stop, the timer will calculate the extra time needed to get an extra half stop density from the base exposure. It sounds a bit complicated but the RH Designs timer ( there may be others) takes all the headache out of the calculations - bets bit of kit I have bought.
Density starts to rule the printing process rather than times. I have found it soo much easier to concentrate on the actual print my printing is faster, better (I say so myself :-) ) and more enjoyable.
I've never used an f-stop timer but with the posts I see in this thread and many others I'm getting very tempted. I've also just acquired an enlarger with the Ilford MG head - and the RH Designs dedicated unit looks very well suited to my needs.
As I'm in the middle of starting again in the darkroom my mission is to standardize and simplify every aspect of the process to make the time spent more productive for my needs. The RH Designs analyzer seems like a perfect fit - even though I just picked up a Colorline 5000!!
Time to do some gardening and earn brownie points with the missus!!
If I made a series of test strips of 4 seconds, 5 seconds, 6.4 seconds, 8 seconds, 10 seconds, 12.5 seconds and 16 seconds, would that be a two-stop range in one-third stop increments?
Thanks, would simplify matters and I should be able to make a much more refined test strip from there.
Originally Posted by BobNewYork
I get a feeling from the replies so far that many people are comfortable with f/stop printing while others are skeptical.
Perhaps they find that f/stop printing works fine without the need to buy a dedicated f/stop timer, would that be a fair assumption?
There are others
Just to keep the record "straight", the only other F stop timer I know of is the excellent one made by DA ( Darkroom Automation ). The DA F Stop Timer has been discussed here, along with the excellent timer made by RH Designs. Mr. Lindan and Dr. Ross have often contributed to the thread about F stop timers, and in general, have maintained a respectful and much appreciated collegial relationship. There are undoubtedly proponents of each timer, but upon analysis, I suspect ( not owning the RH timer does not allow me to speak with complete confidence ) that the differences between the two products are likely rather superficial in that each is capable of delivering the results promised. One is, forgive the analogy, a "Canon", and the other is a "Nikon".
If there are any other F stop timers, then I am sure the group would like to learn of them. A search of the APUG archives will allow one to learn just about all that one needs to about both of these well made products. More information can be garnered from the respective web sites.
Best of luck with which-ever of the timers one decides to use.
Originally Posted by sim
I agree with your statements above, 100%, Dan! I love my StopClock Professional, too, in terms of the channels and f-stop adjujstments as well as the easy split-grade printing feature.
Originally Posted by FirePhoto
Looking over the RH Designs timer from the UK I didn't see a pound / dollar converter, is the timer only available from the UK or is there a distributer in the US? I wonder about the prices of the units. The cold light compensator is a good idea, if one get that model can it be used on halogen based light sources too without the compensator?
I think if you go back through the replies you will find that the only people who are skeptical of f-stop timers are those that don't have them. There are many who started out skeptical, got a timer, and instantly became converts.
Originally Posted by Keith Tapscott.
Darkroom Automation provides a 30-day money-back guarantee, if after using the equipment you are still skeptical then return it. Nobody has, that has to say something...
I don't know that RH provides a similar guarantee in the UK, but I am under the impression it does.
An F-Stop timer is to the darkroom what the shutter-speed and aperture controls are to a camera. When was the last time you used a camera that didn't have marked controls?