f/stop printing versus real-time.

[Mahler_one]

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.

Ed

Hallo,

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.

Simo.

 

[tbm]

I learned and used f/stop printing and split grade printing before I purchased my Stop Clock Pro, using an f/stop chart that I got from Ralph Lambrecht's web site. I believe that I could print just as well with a standard timer and the chart. But the timer makes my darkroom sessions more productive: if I decide, for example, that the highlights need to be just a little darker I can easily and quickly add 1/4 stop to channel 1, for instance. Or if I decide the picture needs a little less contrast I can quickly add 1/3 stop to the highlights on channel 1, and subtract 1/3 stop from the shadows on channel 2. The times for any burns that I have previously worked out are automatically recalculated to the new base times.

The timer is simply a tool that makes me a more efficient printer, reduces math errors, and lets me think more about the product than the process. That said, you would have a fight on your hands if you tried to take it from me!

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.

 

[Curt]

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?

 

[Nicholas Lindan]

I get a feeling from the replies so far that many people are comfortable with f/stop printing while others are skeptical.

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.

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.

 

[Ken N]

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?

 

[Martin Aislabie]

Thanks, would simplify matters and I should be able to make a much more refined test strip from there.
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?

Keith, I was a sceptic until I bought an StopClock Pro

I think its true of most who don't use one - they wonder what is all the fuss about

However, when you have tried one you will understand why those who have them love them so much

I was swayed by all the best printers I know use them and swear by them - there is a hint in there somewhere

Martin

 

[BradS]

...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?

I am not at all skeptical of the process. In fact, quite the contray. As for the stop clocks, I am thrilled to find such modern conveniences available but, I simply cannot justify the expense right now. So, as much as I would love to have one of the technological wonders, I'm going to muddle along with my $20 Omega Repeating Audible timer. Until yesterday, I thought it was the cat's ass in enlarger timers.

 

[RH Designs]

Curt, the pound/dollar rate today is approx $1.47 making a StopClock Professional delivered to the US approx $310. There is a link to a converter www.xe.com on our ordering info page. Sorry, for some reason APUG won't let me embed URLs today.

Yes, we also offer a money back guarantee, 14 days but flexible in the case of overseas customers to allow for shipping times.

 

[ic-racer]

Actually the way it would work is that the exposure difference required to produce the same density difference for a middle gray across all contrast grades would be standardized......

I just wanted to point out that I was making a hypothetical point and that I have great respect and admiration for any person or business that is catering to darkroom users. I am personally familiar with the Darkroom Automation equipment and would highly recommend it to anyone looking for a timer or meter.

 

[Andrew Moxom]

Richard, can the RH Designs stop clock pro interface with a Beseler 45 universal head? I have one of these.

 

[RH Designs]

Richard, can the RH Designs stop clock pro interface with a Beseler 45 universal head? I have one of these.

Hi Andrew

I'm not familiar with that head, but basically if the lamp can be switched on and off by simply applying mains power, then "yes". Like 99% of enlarger timers on the market, the StopClock is fundamentally a mains on-off switch. The clever bit simply involves knowing when to switch on and off.

 

[Roger Thoms]

Curt, the pound/dollar rate today is approx $1.47 making a StopClock Professional delivered to the US approx $310. There is a link to a converter www.xe.com on our ordering info page. Sorry, for some reason APUG won't let me embed URLs today.

Yes, we also offer a money back guarantee, 14 days but flexible in the case of overseas customers to allow for shipping times.

I just ordered and received a paper flasher from RH Designs. I was quite please with their service, shipping was very reasonable and my order arrived promptly. Now that I have a paper flasher that works in F-stops, I'll probably have to get a F-stop timer.

Roger Thoms

 

[fotch]

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?

The trouble I have in understanding this comparison is on a camera, the lens uses F stops and the shutter uses time. On the camera, I would have trouble thinking of it as set the lens F stop and set the shutter F stop.

All the great photographers of old did not have one of these. Now, that said, maybe it is easier for some, but for the money, since I never had a problem, I would find it hard to want one.

On the other hand, maybe using one my photos would be better. After all, a lot of camera/lens and other tools are purchase with the same expectation of improvement.

If I win the lotto I will buy one, maybe.:rolleyes:

 

[Vaughn]

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?

I don't quite know how this relates, but I set the f stop on my camera lens, then decide how many seconds the exposure time will be. Which is exactly how I determined the exposure of my silver gelatin prints.

So count me in on the side of the skeptics...well, perhaps not skeptics, but just one who seemed to be able to print with a regular timer quite easily. A single test strip in 5 second intervals, pick a time and start printing. My burning was more in line with Michael Smith's..a dance I greatly enjoyed.

If I start making silver gelatin prints again, perhaps I should try one of these devices. I do not know why it would do a better job of telling me if I should print at 22 seconds or at 23 seconds at f11 than any other timer, but perhaps some day I will find out.

For now I'll print without a lens and without f stops, and just figure out if the exposure should be 6 minutes or perhaps 6 minutes and 15 seconds.

Vaughn

 

[Nicholas Lindan]

The trouble I have in understanding this comparison is on a camera ... set the shutter [in] F stop[s ?]

The term ‘f-Stop Timer’ is unfortunate, but historical. In the old days before dedicated f-stop timers people were taught the traditional f-stop numbers from lenses generated a 1/2 stop progression of times: 1, 1.4, 2, 2.8, 4 ... seconds, and those who could remember lens 1/2 stop sequences had the 1/4 stop time sequence down pat: 1, 1.2, 1.4, 1.7, 2.0, 2.4, 2.8, 3.5, 4, 4.8, 5.6, 6.8 ... These times still show up in f-stop timers.

But the shutter speed sequence on a camera also follows the same progression of numbers as f-stops: 1, 2, 4, 8, 16, 30(32), 60(64), 125(128) - but at every other f-stop number.

Stops are powers of two and so the same sequence of numbers shows up time and again. “f-stops” as applied to lenses are the square roots of the shutter speed sequence because a lens f-stop number refers to the diameter of the diaphragm opening instead of the area.

All the great photographers of old did not have one of these. Now, that said, maybe it is easier for some, but for the money, since I never had a problem, I would find it hard to want one.

The Daguerreotypists said that of the wet-plate photographers,
who said the same of the dry plate shooters,
who had the same claim against the sheet film users,
who in their turn went livid at the thought of roll film snap-shooters,
who laughed at photographers using 35mm with its postage stamp sized image,
who sputtered in apoplexy at the thought of digital.

They were all right, and they were all wrong.

You will never know until you try.

On the other hand, maybe using one my photos would be better. After all, a lot of camera/lens and other tools are purchase with the same expectation of improvement.

I will guarantee you an f-stop timer will increase your enjoyment of photography more than spending the same money on a new lens.

If I win the lotto I will buy one, maybe.

Buy a Darkroom Automation Lottery ticket, just $5, every day for just 5 short weeks and win the lotto - take home a brand new f-Stop Timer.

 

[RJS]

All you young whippersnappers with too much money! What's wrong the good old hourglass? 0 carbon footprint, doesn't break down, somewhat reliable, depending on humidity etc., and they come in unlimited sizes and colors!

 

[markbarendt]

All you young whippersnappers with too much money! What's wrong the good old hourglass? 0 carbon footprint, doesn't break down, somewhat reliable, depending on humidity etc., and they come in unlimited sizes and colors!

I like that idea! (For now)

Are they available in f-stop increments.

 

[Vaughn]

All you young whippersnappers with too much money! What's wrong the good old hourglass? 0 carbon footprint, doesn't break down, somewhat reliable, depending on humidity etc., and they come in unlimited sizes and colors!

Hourglass?! You techno-freak! Use a stick and a few marks on the ground and go solar! A sun dial is all you need!

Vaughn

 

[MattKing]

I use the table on Ralph Lambrecht's wonderful website and book, and appreciate it greatly. I think that if you start using that, and find that it suits your approach, that you will likely really benefit from an f/stop timer (either brand)

I was looking at buying a DA timer rather than an RH Designs product (due to shipping costs, initial price, and similar financial concerns), but I ended up picking up an Omega D6 enlarger with an Ilford Multigrade 400 head and controller from Craigslist instead. I sure wish there was an interface or adapter.

Matt

 

[jeroldharter]

Richard, can the RH Designs stop clock pro interface with a Beseler 45 universal head? I have one of these.

I don't think it can because the light source has to be turned on by the integrated controller/timer in a closed loop process.

 

[RH Designs]

Use a stick and a few marks on the ground and go solar! A sun dial is all you need!

Vaughn

In a darkroom?!

 

[Ross Chambers]

A vote for RH Designs Ilford 500 timer, but I DO use Ralph's tables for split grade printing when using the same head and the Ilford controller for contact printing only, which makes for a fairly simple roundabout f- stop procedure, however one which usually costs more paper than the RH Analyser Pro for projection printing.

A marginal thought: when I purchased the RH Analyser Pro I had some thought of the possibility of the Ilford controller deciding to die one day and leave the whole setup useless.

Regards - Ross

 

[RJS]

Goodness gracious, people. The light source comes from above through the hole you've cut in the ceiling! As for the 'darkroom' aspect of which Richard speaks, I understand there is a period during rotation when the sun is not visible. For those overdeveloped negatives moonlight is the perfect source!

 

[John W]

There is a link to a converter www.xe.com on our ordering info page.

On the topic of modern conveniences, I'll observe that Google does conversions as well. e.g. try searching for "10 GBP in USD". For Firefox users, know that you can jump straight to the search box via Ctrl-k (win)/Cmd-k (mac).

 

[RalphLambrecht]

What does an f-stop timer do that an ordinary timers doesn't? I guess I shoould read the book but, can somebody give a brief overview?

I can offer this link:

Dead Link Removed

It's an introduction but give you all you need to get started.