Clear 211 enlarger lamp substitute

[pstake]

I just picked up a 4x5 enlarger a few decades older than me.

It's a Federal 450 diffuser enlarger and fortunately it's been well taken care of, and came to me in working order with its recommended bulb.

Even though the bulb works fine, now, I would like to get a spare to keep on hand.

The bulb is basically a common ph211 but it's clear. I can't find any exact replacements and I've done a lot of searching.

I have found similar, clear, tungsten-element bulbs but they all have writing at the top of the dome.

Will this affect the exposure? I have never used a diffuser enlarger so I'm not sure what the rules are. On a condenser enlarger, I've read that writing on the dome of the bulb can/will put a dead spot in the center of the image.

The other idea I had was to use a ph211 opalescent bulb. I expect this would increase my exposure times but would it have any other deleterious effects?

I appreciate any ideas from others who have dealt with this issue.

Cheers,
Phil

 

[Tom1956]

If this is a diffusion enlarger, I have found on the one occasion I tried the idea of just going ahead and using an opalescent bulb actually caused a hot spot in the center. But it wasn't on a Federal enlarger. It was something else. I've forgotten. That was probably in the 80's when I tried that experiment.
Although on bulbs with writing on them, it's usually a simple matter to 000 steel wool it off. I think you'd really want to find the right bulb, if at all possible. It might have had its filament arranged in a prescribed manner on its posts inside the bulb.

 

[pstake]

Thanks, Tom. I ordered one of the bulbs with the writing at the top and I'll compare the two. I'll post a quickie photo of the two side-by-side on this thread.

 

[pstake]

The larger bulb is the original 211-C that came with the enlarger.

The smaller one is the one I ordered. It's an aero-tech 75w with a tungsten element. It had a stamp on the top of the dome, which came off very easily with steel wool. I haven't tested the two bulbs against eachother yet but will post results when I do.

 

[Ronald Moravec]

Acetone will remove the stamp. If you do not remove it, it will be on every print.

Order from B&H. Length is fairly critical for even illumination

 

[Tom1956]

Acetone will remove the stamp. If you do not remove it, it will be on every print.

Order from B&H. Length is fairly critical for even illumination

+1. Length of bulb is paramount.

 

[elekm]

You know, the government is outlawing production of nearly all incandescent light bulbs within the next two years, although production of the PH211 and the other bulb ended more than a decade ago, I think.

I've refitted a couple of very old enlargers, first with a CFL and then with an LED bulb.

I once tried a regular bulb in an Omega D3 with a condenser head. In some of the photos, you could see the bulb maker's logo. In others, you could see the filament.

 

[pstake]

Mike, have you tried one of these? I'm looking at this one and a few other LED's

Dead Link Removed

Color temperature, light output and length are all very similar. Pretty expensive, though, which is why I haven't pulled the trigger yet.

 

[Bob Marvin]

If, as I think is correct, the length of the bulb IS critical, might not a socket extender, like this:

http://www.amazon.com/Porcelain-Med...10&sr=1-2&keywords=light+bulb+socket+extender

be usable with a shorter bulb?

 

[Bob Marvin]

AFAIK regular opal PH 211 bulbs are still being made and the continued production of specialized bulbs will be permitted. Still, the demand will be low, so stock piling a supply isn't a bad idea. My enlarger, an Omega B8, uses PH 111A bulbs, which have an odd socket. These too are still made, but I have enough for probably several lifetimes, just in case

 

[Bob Marvin]

Also, has the OP actually tried a regular, current production, opal PH 211 bulb? I suspect it'd work fine, with little or no additional exposure time required.

 

[pstake]

Also, has the OP actually tried a regular, current production, opal PH 211 bulb? I suspect it'd work fine, with little or no additional exposure time required.

I haven't tried the opalescent ph211.

It seems like that might also have an effect on the print quality since the light is then being diffused twice (once through the bulb and again through the diffuser) before it hits the negative.

Opalascent bulbs were around when this enlarger was built in the 40s so I have to assume they used a clear bulb for a reason ... but I'm not above giving it a try.

The original bulb measures 120mm in length, or about 4.73 inches. The filament peaks at about 1.5inches from the dome of the bulb. Does anyone have measurements for a PH211?

 

[pstake]

If, as I think is correct, the length of the bulb IS critical, might not a socket extender, like this:

http://www.amazon.com/Porcelain-Med...10&sr=1-2&keywords=light+bulb+socket+extender

be usable with a shorter bulb?

This is good to know. I might give it a try. Thanks!