75 watt or 150 watt bulb for 5x4 enlarger?

[Anton Lukoszevieze]

I just got a 5x4 Envoy enlarger, quite primitive but all there. Am going to use it for my quarter plate negs. It has a condensor head. What wattage of bulb should i use? Is either oK and I will just get longer or shorter exposure times?

I've been using a Graflex super d 3x4 with a kodak ektar 15mm lens which rocks. Why oh why did this format and indeed this camera fade out?....I've asked that question before here.........so just a bulb answer please!

Thanks

Anton

 

[Nick Zentena]

Whats in it now? -) Unless somebody has used an Envoy it could be either.

If the setup can't handle the heat etc of the 150w that could cause problems.

 

[Anton Lukoszevieze]

what was in it?

Dust.


Though have just put in a 75watt, which looks oK.......


Thanks

A

 

[richard ide]

Hi Anton,

If a lower wattage bulb works use it. Your exposure times may be a little longer but you will have less of a problem with heat. If your negative carrier does not have glass (I am not familiar with your enlarger) you can get film movement as the negative heats up.

 

[elekm]

A lower wattage bulb will give you longer enlargement times. That can be a positive factor, because it will allow you to more precisely control exposure.

 

[Monophoto]

I'm not familiar with the Envoy, but I use a 75w bulb in my Omega DII.

As others have noted, a lower wattage bulb will avoid heat problems and require longer exposures, which will then allow more time for printing controls. And the Ph211 75w bulb is probably easier to find than the brighter Ph212 or Ph 213 bulbs.

Frankly, condenser enlargers inherently tend to be fairly bright, so a 75w bulb is usually quite adequate.

 

[Ole]

I've just replaced the 300W bulb in my 5x7" enlarger with a 27W CFL. Less heat, shorter exposures. I leavie it on the whole time I'm in the darkroom, and use the lens cap for exposure control. After siz hours it's not even warm - I used to have to stop after about two hours to step outside to cool down!

 

[Jim Jones]

My ancient DeJur runs much cooler with 150 Watt lamps than my Omega B22 did with its little 75 Watt lamps.

 

[tim_walls]

My safelight bulb blew this afternoon; I took this as a warning shot and ordered a stock of bulbs for the enlarger at the same time as for the safelight. I couldn't find any 150w bulbs though and got 75w ones instead - I assume it's safe to assume double the time is a suitable starting point for finding new exposure times?

(i.e. Does light output from an incandescent bulb follow wattage linearly? Stupid question I'm sure...)

 

[Deckled Edge]

I'm not familiar with the Envoy, but I use a 75w bulb in my Omega DII.

As others have noted, a lower wattage bulb will avoid heat problems and require longer exposures, which will then allow more time for printing controls. And the Ph211 75w bulb is probably easier to find than the brighter Ph212 or Ph 213 bulbs.

Frankly, condenser enlargers inherently tend to be fairly bright, so a 75w bulb is usually quite adequate.

I agree with Louie. Get the Sylvania Ph211, available at any good camera store. It has the writing on the side, not on the top like a std. 75W bulb. I keep several on hand for my DII and have never wished for a brighter bulb.
(Except for that time I tried to enlarge Azo, but that's a different story) : - ))

 

[DeBone 75]

For my Bessler 4X5 I use a 150 watt with a dimmer switch. This allows me to print just about every screwed up negative I have. Most of the time I have it set at about 50% or 75w.

 

[fschifano]

(i.e. Does light output from an incandescent bulb follow wattage linearly? Stupid question I'm sure...)

Not so stupid really. But no, that's not the way it works. I took down the specs for Sylvania's standard household incandescent bulbs and plotted light output in lumens against bulb wattage. The higher the wattage of the bulb, the more lumens per watt you get.

If you have MS Excel or Open Office, you can open the attachment.

 

[Jim Jones]

. . . Does light output from an incandescent bulb follow wattage linearly? Stupid question I'm sure...)

Other factors affecting output are the coating on the bulb interior and the bulb voltage rating versus the supply voltage.

 

[tim_walls]

Thanks for that Jim/fschifano - much appreciated. I'll keep that spreadsheet around; when my last 150W bulb blows I'll have somewhere to start my calculations from