Gralab 300 - Using With Enlarger?

OPTheory · Jul 24, 2007

Hey there,

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?

ann · Jul 24, 2007

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.

bdial · Jul 24, 2007

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.

Nick Zentena · Jul 24, 2007

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.

matt miller · Jul 24, 2007

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.

Konical · Jul 24, 2007

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.

Konical

Chan Tran · Jul 24, 2007

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.

Monophoto · Jul 24, 2007

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.

Michel Hardy-Vallée · Jul 24, 2007

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).

DBP · Jul 24, 2007

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.

fotch · Jul 24, 2007

Never had a problem, however, did start using an electronic one for additional features.

panastasia · Aug 1, 2007

I own the GraLab 300 and 400. The 400 is the auto reset version, both are similar except for this function and maximum time set; 300=60 minutes, 400=60 seconds. The safelight off during exposure function works the same for both. Very accurate and reliable. One caution though: they don't work with voltage stabilization, therefore, not recommended for color printing which requires stabilized voltage to avoid color shifts caused by changing lamp color temperature, which occurs during current fluctuations when other appliances are working in the same circuit.

I now use compensating timers for cold light printing and developer temperature change compensation.

fschifano · Aug 1, 2007

OPTheory said:
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.

There's nothing wrong with that timer. I have one that's very old and it continues to work consistently and accurately. I've compared it against a quartz controlled electronic timer and they match.

There are two switches on the timer. The switch at the top left is used for focusing the enlarger. Set it to "focus" and the safelights are switched off and the enlarger is switched on. The timer is out of the circuit. At the top right there is another switch. This one powers the timer. Switch it off to set the time. Safelights and enlarger lamp will be switched off. When you are ready to make the exposure, flip this switch on. The timer is now in the circuit. The enlarger will be on for the preset amount of time. The safelights will turn on automatically at the end of the exposure time.

JHannon · Aug 1, 2007

mhv said:
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).

Thats what I do too, there is something nice about the old analog clock face and makes it easer to time the agitation cycle.

I have a cold light and use a Zone VI compensating timer for my enlarger which works well for me. I will keep the Gralab for film developing.

--John

panastasia · Aug 1, 2007

Paul Horowitz who modified the Pentax Spot Meters also developed/designed the Zone VI compensating enlarging timer as well as the Zone VI film/paper compensating developer timer. I own all three and never found a need for anything else that came along since the early 80's as they provide complete control of the entire manual process.

My GraLab timers are still in service though; for timing a toning process, print washing, and dry mounting, among others.

luvmydogs · Aug 4, 2007

I don't mean to hijack the thread, but I have to ask - so the faint glow of light that this timer gives off when the room is dark does not negatively impact film development? (I'm speaking of development of LF film in trays)

fschifano · Aug 4, 2007

No. It's fine from a few feet away.

John Kasaian · Aug 23, 2007

I aspired to a Gralab 300 for years (this was pre-digital---back when that last wooly mammoth slide into the LaBrea tar pits) and finally got one several years ago. I love it! Its simple and so, I've been told, am I

Gralab 300 - Using With Enlarger?

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