Gralab 300 - Using With Enlarger?
I'm now in possession of a Gralab 300 along with a bunch of other darkroom equipment that I picked up off of craigslist. While putting everything together I noticed that the timer had two power jacks on the side labeled "Safelight" and "Enlarger". So I plugged in both to the timer and tried it out. The safelight turns off when the enlarger is on. I actually found this to be incredible, it made me smile to go from a fairly bright red room to a very dark room with only the image seen on the easel and back again to the red. I've seen these timers but the only thing I thought they were good for was just keeping track of development times.
Normally we'd use time-o-lites or those Gralab digital timers with the enlargers. I don't even think they "switch" the lighting sources like the Gralab 300 does. But the nice thing about them is that the timing is spot on for every exposure. I can see that with the Gralab 500, if you put the second hand on the five--it could be off by a half second if you take it too far or too little. Even if you're slow to take the hand to the five, it'll turn on the enlarger before you're done rotating the arm to it.
So how do you guys make this work? Is it really a good device to time an enlarger with or do you suggest another type of timer?
in my darkroom at home the safelight is not on when i make an exposure. At school in a gang darkroom that is impossible.
i would never use that timer with an enlarger, but with film and paper, however, that is just my choice.
the draw back for me, it does not reset it's self.
I'd recommend another type of timer. As you've discovered, a Gralab 300 will work, but it's tedious to reset after every exposure, and it can be inaccurate for short times.
Most timers do have safelight outlets, I've never used that functionality though.
I've opted for a digital Gralab, largely because the lighting is sparse where my timer needs to live, and exposures on my big enlarger tend to be pretty short. Time-o-lites work well though, and they are cheap.
I don't know. I started with a gralab in high school. So for me it still seems normal. Every thing the previous two posters is true. But it'll work fine for B&W printing IMHO. OTOH I HATE the Gralab 450.
It's more of a problem with colour prints. But with B&W the times are long enough that all the issues the 300 has don't matter much to me.
I have 2 Gralab 300's. I have one at the sink that I use for timing developement of film and paper. The other is on my dry side. I use it for making prints. The timers work wonderfully for all of my needs.
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Good Morning, OP,
I purchased my Gralab 300 over thirty years ago; it's been my only timer ever since. I once had to replace a toggle switch (simple repair, switch easily available at any hardware store), but, otherwise, it has worked very reliably.
My Gralab 505 digital works the same way as your 300 that is it turns off the safelight when it turns on the enlarger and then turns the safelight back on when the exposure is done. It's easy to implement such a thing with a timer that only controls the enlarger.
As others have noted, there are two problems with using the GraLab 300 timer to control and enlarger.
1. It is necessary to reset the timer for each exposure, with an associated risk that the time won't be set consistently from one exposure to the next.
2. The timer has a 60 minute range, and in theory can be set in one second increments. However, those settings are not very precise, and the actual timing resolution is probably more on the order of 2-3 seconds.
My suspicion is that in the good old days of long printing exposures, the imprecise nature of the timer was not significant. A 2-3 second error in a one minute exposure is not noticeable. But I find that exposures with modern papers are much shorter than I recall from my early darkroom days - most are in the range of 5 - 25 seconds - so that 2-3 second error is more significant today. And because of the need to reset the timer for each exposure, the error is random and not repeatable.
I use an old GE timer that I purchased used for $5 when I first set up my darkroom 30 years ago. It also has a nominal one second resolution (which is probably more like 2 seconds in actuality), but it has a preset function that makes any error repeatable.
I use my GraLab on the wet side. It also was used when I bought it (also for $5), and other than refreshing the phosphorescent paint on the hands, it's essentially the original timer. They are like battleships and last forever.
I tried using a Gralab for my enlarger, but I soon realised that occasionally my cold light took a second or two before lighting up. Instead I just use a clock with a tick, and a sheet of cardboard as a "shutter." I put the cardboard over the easel, light up the lamp, wait for a second, then start counting the ticks as a flip away the cardboard. I flip the cardboard back to stop exposure, and then I close the light.
However, I found that the gralab is perfect for timing film development: set the dev time, and agitate whenver the second needle is at the right position (30s or 1min, depending on my combo).
Using film since before it was hip.
"One of the most singular characters of the hyposulphites, is the property their solutions possess of dissolving muriate of silver and retaining it in considerable quantity in permanent solution" — Sir John Frederick William Herschel, "On the Hyposulphurous Acid and its Compounds." The Edinburgh Philosophical Journal
, Vol. 1 (8 Jan. 1819): 8-29. p. 11
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I've used a Gra-lab 300 for years with no complaints, other than the occasions when I flip the switch to focus instead of time. It never occured to me that I was missing something by not having it record the time of the prior exposure - I keep a whiteboard nearby for recording all that. I don't use the safelight switch because the safelights are in light sockets in the ceiling. Compared to the elephant system I used as a kid, or the little spring wound timer I used after that, the Gralab is a wonderful machine. In fact I just bought an old 168 so I would have one for each enlager.