Test strips with Phillips PCS 150 Control Unit

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Crit-ter85

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I just picked up a Phillips PCS Enlarger with a PCS 150 control unit. Does anyone have one that would be willing to share how you make a test strip? The shortest time I can set it for 5 seconds. Thanks!
 

koraks

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Welcome to Photrio!

Assuming this is for B&W printing (correct?), here's what I'd do in your case:
* Compose and focus negative onto the baseboard to the desired print size.
* Take a test strip of B&W paper a ca. two inches wide and a couple of inches long (let's say 5 or so). We all have our preferences for dimensions; YMMV and all that. Just start somewhere and scale up/down as desired from there.
* Set aperture of the lens to f/8 (you can adjust later if necessary)
* Set color filtration to zero - so 0R, 0G, 0B.
* Position paper so that important light and dark areas of the image project onto the strip.
* Expose the entire strip for 5 seconds.
* Cover a half-inch band of the test strip with a piece of stiff carboard that you hold over the strip and expose for another 5 seconds.
* Move the cardboard mask half an inch further so that a full inch of the strip is now covered. Expose for 10 seconds.
* Move cardboard mask another half inch. Expose for 20 seconds.

Develop the strip and evaluate the results. You now have a strip that's exposed in increments of one stop (5, 10, 20 and 40 second bands). If the 5 second band is too dark overall, stop down the aperture on the enlarging lens one or more stops and repeat the process. If the 40 second band is still too light overall, open up the aperture and repeat the process. The latter is unlikely as today's papers are generally quite fast, with the exception of warmtone papers such as Fomatone.

Select the band that's closest to the image as you'd like to see it. If the contrast is too low, i.e. shadows are too light and highlights too dark, dial in more blue filtration and repeat the test strip process. If contrast is too low, dial in blue filtration and repeat the process.
To fine tune the exposure time, make another test strip with exposure times closer to each other. Given the limitations of your timer, you may have to make a couple of strips with one exposure time each, or you may have to make a little mask that exposes only part of a piece of paper in one go.

One more thing: if your test strips come out too dark, resist the temptation to reduce the development time. Always develop the paper 'to completion', i.e. until there's no more visible change in the print/strip during development. For RC paper, this is usually between 1 and 2 minutes development time. For FB papers, it's generally 2-3 minutes. Refer to the guidelines that come with the print developer and enlarging paper of your choice.

Everyone has their own ways of working, so hold on for some more ideas from other members and choose the approach that makes the most sense to you. Eventually you'll end up working your own unique way, inspired by what you pick up from others and your own experience. There's no 'right' or 'wrong' way to do this. There are many ways to get the job done.

An approach called 'split grade printing' is undoubtedly also going to be proposed by some. Consider it and certainly try it at some point. If it's the best place to start, I can't say. For some, it's very intuitive, for others, it's confusing and complicated. YMMV. Again: no right or wrong way, many options to choose from :smile:
 

snusmumriken

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The Philips PCS is a surprisingly excellent enlarger! All the above is also excellent advice.

There’s a hint in your question that you think 5 sec too long as a minimum? If your entire test strip turns out very dark, you can stop the lens down further; use a lens with a longer focal length (probably not an option?); or add a neutral density filter in the filter drawer. It may also be possible to dial in filtration on all 3 channels to achieve the same effect, but I don’t have the colour head on mine, so I’ll leave that for others to advise on.

I strongly recommend reading Ralph Lambrecht’s Way Beyond Monochrome for further guidance. In particular, the approach of using a test strip of a highlight area to determine exposure time, then another of a shadow area to determine contrast grade.

Others here will want to persuade you to use f-stop time increments (i.e. a logarithmic series) to make your test strips. This is also covered in Ralph’s book. My advice is to start simply with equal time steps as described above. You might decide to use f-stop timing later, but then you’ll almost certainly want to buy a different controller. FWIW, I don’t use f-stop times, and feel no reason to.
 
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brbo

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There’s a hint in your question that you think 5 sec too long as a minimum? If your entire test strip turns out very dark, you can stop the lens down further; use a lens with a longer focal length (probably not an opton?); or add a neutral density filter in the filter drawer. It may also be possible to dial in filtration on all 3 channels to achieve the same effect, but I don’t have the colour head on mine, so I’ll leave that for others to advise on.

Yes, it's very easy to dial in neutral filtration* to get longer print times. I do it all the time (yes, I know, this will now inevitably start the "cyan filtration should NEVER EVER be used").

* with PCS 150 you are not really adding filtration but decreasing the power of R,G,B light.
 

ic-racer

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I think there is a little bleed of yellow by the red lamp, so turning it off is not unreasonable with multigrade printing. Though it is so slight, probably makes no difference either way.

I have not made a conventional test strip for 20 or 30 years. I never found much value in seeing different parts of the image with different exposures.
 

snusmumriken

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I have not made a conventional test strip for 20 or 30 years. I never found much value in seeing different parts of the image with different exposures.

That’s probably going to seem quite enigmatic to the OP. Shouldn’t you explain what you do instead, and whether it can be done with his equipment?
 

ic-racer

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Write these down on or near the calculator:
1/2 = one-half stop = 1.4 multiplied or divided the initial time
1/3 = one-third stop = 1.26 multiplied or divided the initial time
1/4 = one-quarter stop = 1.19 multiplied or divided the initial time, etc.

The way I do it, there is no advantage to exposing the strips ahead of time, because the next step isn't known until the first one is dry.

The little white frame below lets me keep the position of the little pieces consistent.

After this I make a full print, and I will dodge and burn it from the start. I carefully examine the projected image with the lens open and all the lights in the room off. With years of experience one can get a good idea of how it needs to be controlled. Otherwise, when starting out, make a straight print first, then dodge/burn based on how that looks.

In this example the negative was 'easy to print' with only six initial exposures. With difficult negatives, I'll spend the entire darkroom session working up sections of the print before a single full sheet is ready to be exposed.
test strips.JPG
DSC_0746.JPG
test strips.JPG
 
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snusmumriken

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OK, I don’t mean to be cheeky, but for the OP’s sake is it fair to summarise like this?:

You start with a guessed exposure and contrast grade based on long experience. You check and then fine-tune that using separate small pieces of paper placed on critical parts of the print, rather than making a step sequence of exposures. You change the exposure on an f-stop (logarithmic) basis, rather than just adding or subtracting a few seconds to each successive exposure.

It doesn’t sound as though the OP is ready for that yet. I think he’s right to focus on doing conventional test strips. Quite likely he will never feel a need to do otherwise.
 
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Crit-ter85

Crit-ter85

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While I appreciate the many responses, I guess I didn't make it clear that I do know how to make a test strip, in general. I also have an Omega D5 enlarger with a Darkroom Animation F-Stop timer, so I know how to make a test strip using either the time-method or the F-Stop method.

I make lost of small "working prints", about 4.75x4.75 on 5x7 paper and my base exposures are often around 10 seconds at F/11. I know I can stop down to increase the exposure time, but I'd rather make my exposures at the optimal f-stop of my enlarging lens, if possible. So running a test strip at 2 second intervals, or less, is pretty important to dial in the exposure time when it's around 10 seconds.

Currently my solution will be to get a timer that beeps every second. I can expose the test strip for the base exposure (let's say 6 seconds, for example), then do a second exposure of 10 seconds, moving the sheet of black paper blocking the light every 2 seconds. It's not nearly as exact as using an actual timer, but it would work. I was hoping someone else would have a better solution than that.
 

MattKing

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You might consider an ND filter to decrease the light intensity.
 

snusmumriken

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While I appreciate the many responses, I guess I didn't make it clear that I do know how to make a test strip, in general. I also have an Omega D5 enlarger with a Darkroom Animation F-Stop timer, so I know how to make a test strip using either the time-method or the F-Stop method.

I make lost of small "working prints", about 4.75x4.75 on 5x7 paper and my base exposures are often around 10 seconds at F/11. I know I can stop down to increase the exposure time, but I'd rather make my exposures at the optimal f-stop of my enlarging lens, if possible. So running a test strip at 2 second intervals, or less, is pretty important to dial in the exposure time when it's around 10 seconds.

Currently my solution will be to get a timer that beeps every second. I can expose the test strip for the base exposure (let's say 6 seconds, for example), then do a second exposure of 10 seconds, moving the sheet of black paper blocking the light every 2 seconds. It's not nearly as exact as using an actual timer, but it would work. I was hoping someone else would have a better solution than that.

If you can find one, a lower wattage bulb would be the simplest. At least 2 wattage options were available back along.
 

ic-racer

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OK, I don’t mean to be cheeky, but for the OP’s sake is it fair to summarise like this?:

You start with a guessed exposure and contrast grade based on long experience. You check and then fine-tune that using separate small pieces of paper placed on critical parts of the print, rather than making a step sequence of exposures. You change the exposure on an f-stop (logarithmic) basis, rather than just adding or subtracting a few seconds to each successive exposure.

It doesn’t sound as though the OP is ready for that yet. I think he’s right to focus on doing conventional test strips. Quite likely he will never feel a need to do otherwise.

No problem with you comments. What I originally was trying to convey to the OP is that "I'm not giving an answer your original question because I don't do test strips."
And, yes my method is personal preference and probably, as Allen Holdsworth would say, "Just for the Curious."
 

ic-racer

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Personally I find my PCS150 low powered. I have new bulbs to go in to see if that will help, but have not installed them yet. The bulbs are hard to come by BTW, they are not standard MR16.
Philips PCS 150.JPG
philips lamp.JPG
 
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