Remote safelight suggestions needed

[koraks]

If actually doing it I would be inclined to set up the transmit end to be powered ahead of the enlarger timer

No need. Takes just a few milliseconds for a uC to power up, send its signal and if so desired even engage in a little confirm-and-repeat. I know, because my darkroom lighting setup relies on such technology. So does virtually every modern remote controlled lighting appliance. Delays are a non-issue with this kind of technology.

 

[reddesert]

No need. Takes just a few milliseconds for a uC to power up, send its signal and if so desired even engage in a little confirm-and-repeat. I know, because my darkroom lighting setup relies on such technology. So does virtually every modern remote controlled lighting appliance. Delays are a non-issue with this kind of technology.

I understand that a microcontroller can start up rapidly, but my concern was really with the idea that it could be put together from mostly off the shelf parts, using it to control a wi-fi controlled power switch. If the device has to negotiate getting onto a home wi-fi network and talk to the switch, it's not going to have an instant startup. If you design both ends of the device for an instantly negotiated wireless connection that's much better but also more work. The actual power switching is certainly fast enough.

I have "smart home" devices that can be controlled from a phone app, and the actual switching is fast, but the startup time and reliability of the app are less than one needs in this application.

 

[koraks]

I agree that a wi-fi controlled switch would be very inappropriate to use here. The common remote-controlled (not app-enabled) power switches don't use WiFi.

 

[Pieter12]

Could a judiciously designed baffle around the enlarger keep some of the safelight dim enough to work? It seems like you have a very bright light if it is interfering so much you have problems seeing the projected image. Also, when I dodge and burn, I use two-sided cards (I cement a white and black pastel paper together) so the image is visible on the white side and I can more easily see what I am dodging and burning. Using pastel paper makes it easy to cut with scissors or an Xacto knife while still having enough body.

 

[MattKing]

Matt, buy one of these and screw it into your ceiling light fixture, plug the safe light into it. All you need to do then is turn on the light, pull the chain to turn off the room light and the safelight stays on. When you're finished, pull the chain to turn the light back on and then hit the wall switch to turn everything off.

Good idea, except it is a bathroom - no ceiling light.
I've always advocated pull chain switches for room lights in darkrooms, but that won't fly for our bathroom!

 

[Rick A]

Good idea, except it is a bathroom - no ceiling light.
I've always advocated pull chain switches for room lights in darkrooms, but that won't fly for our bathroom!

We have a ceiling fixture in our bath, combo exhaust fan and light. I made sure I can control my safelights and main lighting from a master switch, then individually with pull chain and line switches. Too bad you can't do this, would make life easy for you.

 

[MattKing]

Could a judiciously designed baffle around the enlarger keep some of the safelight dim enough to work?

Tough to do with an enlarger on a roll-able cart that actually gets moved from time to time even when the bathroom is set up as a darkroom.
And yes, the safelight is wonderfully bright, and evenly distributed around the working area of the bathroom/darkroom. I can read in there under that light! (if I have my glasses on).
That makes handling things like adjusting the easel and the enlarger, positioning the paper and setting the contrast on the variable contrast light source easy - without having to turn on room lights or using a flashlight.
I just would like to be able to turn off the safelight during the exposure itself.

 

[MattKing]

Thanks everyone for all your great ideas!

 

[Pieter12]

Tough to do with an enlarger on a roll-able cart that actually gets moved from time to time even when the bathroom is set up as a darkroom.
And yes, the safelight is wonderfully bright, and evenly distributed around the working area of the bathroom/darkroom. I can read in there under that light! (if I have my glasses on).
That makes handling things like adjusting the easel and the enlarger, positioning the paper and setting the contrast on the variable contrast light source easy - without having to turn on room lights or using a flashlight.
I just would like to be able to turn off the safelight during the exposure itself.

How about a baffle on the safelight that you could move when you want the whole room bright? That said, I assume you have done a thorough check to make sure the safelight is not only truly safe, but also not limiting the range of your paper (Herschel effect).

 

[MattKing]

The safelight is a 16 foot rope light that is at the join between the wall and the ceiling around three sides of (most) of the room.
And yes, it passes the full Kodak Safelight test with the Ilford and Oriental papers I use.

 

[Rick A]

The safelight is a 16 foot rope light that is at the join between the wall and the ceiling around three sides of (most) of the room.
And yes, it passes the full Kodak Safelight test with the Ilford and Oriental papers I use.

How about an extension cord with a line switch added, then route the cord along the wall using Command strips. Can be done for less than $10.

 

[MattKing]

How about an extension cord with a line switch added, then route the cord along the wall using Command strips. Can be done for less than $10.

Tried that for the safelight - they don't reliably adhere to the paint used in the bathroom, and I'm not re-painting!

 

[Doremus Scudder]

Matt,

It seems like there is no really convenient solution to your problem. Maybe just get used to walking over to the safelight switch when needed.

FWIW, I have four safelights in my darkroom, two Kodak bullets over the dry side on pull-chains, a Kodak D 8x10 safelight bounced off the ceiling in the center (but angled toward the sink side), and a six-foot-long rope of red LEDs filtered through rubylith. These are all powered from a separate switch at one end of the darkroom. The two bullet lights are normally off unless I need then to see to work on the counter (e.g., using the paper trimmer, etc.). When I need less safelight to see a print, for example, when the image is very dim due to extreme enlargement or filtration, I just walk over to the Kodak 8x10 light and switch it off. If that's not enough, then I'll walk to the end of the darkroom and switch them all off. I've never seen the need to use the "safelights off when the enlarger is on" feature of my timers.

If you regularly have problems seeing the projected image from your enlarger, you may simply want to dim your safelights a bit. Yes, being able to read in the darkroom is great, but if the safelight is so bright it makes your printing a pain, then, well...

Best,

Doremus

 

[Craig]

I asked a friend of mine who is an Electrical Engineer and he didn't think there was anything that would do what you want it to without building something and programming it.

 

[MattKing]

Thanks Craig. I'm going to ask an electrician friend who does a lot of work upgrading strata properties.
It would seem to be an ideal solution for a stairwell with lights at the top and bottom that are not wired to the same switch(es).

 

[mshchem]

I've never hooked safelights to my timer. It's certainly easier to compose and focus with out safelights.