Blue light bulbs abd availability of lightbulbs

[LF2007]

I just received a second hand enlarger off e-Bay. It came with a blue 75 watt Philips- lightbulb (transparent). Why would anyone use a blue lightbulb? Does it have any advantages in printing?

[Cruzingoose]

Most likely it was handy and it fit. There is no real reason to use a blue or daylight bulb in a conventional enlarger. I DO use two blue 7 watt and a 7 watt orange "golf bulbs" in my Brumberger 7x5 contact printer. They do a much better job in managing contrast and allows 10-15 second exposures using VC paper.

[ic-racer]

A blue filter blocks the light the paper does not see.

What kind of enlarger is it? Perhaps someone can give a good suggestion on a bulb for that enlarger. Some enlargers have specific requirements.

[LF2007]

It's a Leitz Valloy II

Can I also use regular lightbulbs available in supermarkets?? Or does it have to be a special type of bulb?

I learned that in Europe regular lightbulbs will be banned by 2012. All lightbulbs will be replaced by energy saving lightbulbs. Not sure if you can use energy saving lightbulbs in an enlarger, as they need warm up time. Anyone have experience with them?

[alistair56]

I have a magnifying glass on an extendable arm that came with a tungsten blue bulb. I bought it from someone who did embroidery. According to the manual the blue bulb was to correct the colours of the embroidery thread - a bit like a tungsten filter I guess

[ic-racer]

It's a Leitz Valloy II

Can I also use regular lightbulbs available in supermarkets?? Or does it have to be a special type of bulb?

I learned that in Europe regular lightbulbs will be banned by 2012. All lightbulbs will be replaced by energy saving lightbulbs. Not sure if you can use energy saving lightbulbs in an enlarger, as they need warm up time. Anyone have experience with them?

Ok, so you have a great enlarger. Certainly worth fixing up right. You may be able to get by with a regular 75W bulb, but for best even illumination I'd look for the correct bulb.
Glennveiw has a correct Osram 75W bulb for $15, but I think its the same as the PH/211, here for $5:
https://www.lightbulbemporium.com/ei...3ek_ph_211.asp

This picture from glennview.com shows the box for the Osram bulb.


I don't live in Europe, but I don't think those regulations apply to specialty lamps.

[srs5694]

Just speculation, but: A blue bulb, depending on its exact characteristics, might produce a higher-contrast print on variable contrast (VC) paper than would a white bulb. It's conceivable that the enlarger's original owner liked this and so used a blue bulb to get this effect. Of course, I have no way of knowing this is so; you'd have to run some tests to even verify that the bulb has this effect. If you know who the original owner was, you could ask.

[ic-racer]

Just speculation, but: A blue bulb, depending on its exact characteristics, might produce a higher-contrast print on variable contrast (VC) paper than would a white bulb. It's conceivable that the enlarger's original owner liked this and so used a blue bulb to get this effect. Of course, I have no way of knowing this is so; you'd have to run some tests to even verify that the bulb has this effect. If you know who the original owner was, you could ask.

Blue or cyan filters have no effect on VC or non-VC paper. They block light outside of the paper's sensitivity spectrum. The paper doesn't know or care

[Steve Smith]

Some grain focusers come with blue filters to allow better focussing as you are only seeing the light the paper sees. A blue bulb could have the same effect but this may not be the reason it was fitted.


Steve.

[Adrian Twiss]

It's a Leitz Valloy II

Can I also use regular lightbulbs available in supermarkets?? Or does it have to be a special type of bulb?

I learned that in Europe regular lightbulbs will be banned by 2012. All lightbulbs will be replaced by energy saving lightbulbs. Not sure if you can use energy saving lightbulbs in an enlarger, as they need warm up time. Anyone have experience with them?

The problem with regular bulbs is that they have the branding and wattage information on the top of the bulb. There is a danger it would be projected onto the print. Enlarger bulbs (apart from their very even coating) have the branding and wattage printed on the side.