Enlarger Bulb

[winger]

The printing on a bulb can either be taken off with solvent or with an abrasive paste.

I've had to do this with a couple of actual enlarger bulbs, in fact. One of those safe scrubby sponges (that are fine on non-stick pans) worked pretty well.

And Freestyle has a few other enlarger bulbs if you have the 45MX - that one's different. I took a guess that you had a 23C.

[MattKing]

A plain household lamp is less effective concerning the effective light output, but this would not affect quality.

Of much importance is however the size of a lamp and the transmittance quality of the bulb proper (clear or opal), actually the latter is finally a matter of size too... At least any enlarger that employs a condenser should be fitted with a lamp of proper physical size.

In the latter case the position of the lamp is of importance too.

+1

Most importantly, however, the size and shape of the bulb determines, along with any reflectors in the lamp house, the shape and position of the light source. And the condensers are designed with that shape and position in mind.

If the household bulb doesn't match the shape and position, the condensers won't illuminate the negative evenly, so your prints won't print evenly.

[Molli]

Matt, regarding the size and shape of the bulb, I've just switched out the 75W bulb from an old Durst 606 enlarger into my Durst M600, replacing the 150W globe which was giving me ridiculously short exposure times, even stopped right down. I intended to run some tests anyway, but you've just given me something else to look out for. The 75W bulb is slightly smaller and narrower than the 150W. Do you think this might be much of an issue?

I have a Kodak Wratten ND .20 filter which I was intending to use but my concern with it is how stupidly hot the enlarger gets so I thought I'd try the other bulb out first.

(Apologies to the OP if I seem to be hijacking the thread but I hope any answers elicited to my question might help others also with regard to replacing bulbs... that's my excuse anyway )

[Pfiltz]

(Apologies to the OP if I seem to be hijacking the thread but I hope any answers elicited to my question might help others also with regard to replacing bulbs... that's my excuse anyway )

No worries... The more info, the better.

[MattKing]

Matt, regarding the size and shape of the bulb, I've just switched out the 75W bulb from an old Durst 606 enlarger into my Durst M600, replacing the 150W globe which was giving me ridiculously short exposure times, even stopped right down. I intended to run some tests anyway, but you've just given me something else to look out for. The 75W bulb is slightly smaller and narrower than the 150W. Do you think this might be much of an issue?

I have a Kodak Wratten ND .20 filter which I was intending to use but my concern with it is how stupidly hot the enlarger gets so I thought I'd try the other bulb out first.

(Apologies to the OP if I seem to be hijacking the thread but I hope any answers elicited to my question might help others also with regard to replacing bulbs... that's my excuse anyway )

It's the same concern.

Is the bright part of the bulb where the rest of the optics of the enlarger expect it to be?

There are tests you can do that check how even the light is, and whether all the corners of your negatives are properly illuminated. Printing a slightly fogged piece of film is one of them.

Some times you can add extra diffusion to even things out, but that changes the character of the illumination, which is one of the strengths of Durst enlargers.

[PDH]

Matt, regarding the size and shape of the bulb, I've just switched out the 75W bulb from an old Durst 606 enlarger into my Durst M600, replacing the 150W globe which was giving me ridiculously short exposure times, even stopped right down. I intended to run some tests anyway, but you've just given me something else to look out for. The 75W bulb is slightly smaller and narrower than the 150W. Do you think this might be much of an issue?

I have a Kodak Wratten ND .20 filter which I was intending to use but my concern with it is how stupidly hot the enlarger gets so I thought I'd try the other bulb out first.

(Apologies to the OP if I seem to be hijacking the thread but I hope any answers elicited to my question might help others also with regard to replacing bulbs... that's my excuse anyway )

The 600 and 601 condenser were designed for 75watt bulbs, a smaller bulb may not matter with 35mm but might with the 6X6 condenser packet. My enlager bulbs are the same size as standard household bulds, I have used GE softwhite bulbs in a pinch while waiting for enlarging bulbs in the mail. Using standard bulbs in a Durst is somewhat easier, as the light souce is not stacked on top of the condenser but is off the side so the printing on top of the bulb does not show at all. On the end of the scale I have used oversize bulbs in my D3, almost like a difussion effect.

[Molli]

It's the same concern.

Is the bright part of the bulb where the rest of the optics of the enlarger expect it to be?

There are tests you can do that check how even the light is, and whether all the corners of your negatives are properly illuminated. Printing a slightly fogged piece of film is one of them.

Some times you can add extra diffusion to even things out, but that changes the character of the illumination, which is one of the strengths of Durst enlargers.

Thanks, Matt, I'll keep on eye on that and check around for the best tests to do to determine if the smaller bulb is causing any problems.

[kiku]

Really? Good to know, however; I'm using one bought at Walmart...

Thanks

Really, you shop at Wal Mart??? Howard Tanger

[Michael R 1974]

A note about opal bulbs in general. Try, if possible, to get a real GE or Philips. Many times if you're ordering a PH-xxx bulb on a website the picture will show a GE bulb but what you'll actually get is a piece of crap "Eiko" thing from China or wheverever. These are notorious for having very non-uniform opal coatings, particularly on the top of the bulb - concentric circles, spirals, wavy patterns etc of higher/lower density. With a condenser enlarger, these irregularities WILL show up on the baseboard. I experienced lots of problems with this in my old Omega B66. I still have a pile of crap bulbs I couldn't use. Don't cheap out on the bulb.

[John Koehrer]

Really? Good to know, however; I'm using one bought at Walmart. One you would use in your house in a lamp. It's frosted and has print. The printing on the bulb does show up, when the condenser [Those 2 big pieces of glass] below the light lamp housing, are removed, otherwise; I don't see any printing on the board that the paper sits on.

I guess I can google enlarger bulbs to see if I can grab one somewhere.

Thanks

It can be interesting if you have a large, evenly toned area. Sky? with GE 25 Watt in it. :o)