What is special about enlarger bulbs?

[BetterSense]

When my bulb goes, why can't I just replace it with a 75 incandescent? I'm sure there must be a reason. Freestyle wants $12 for a replacement bulb.

 

[Toffle]

Well, for one thing, most incandescent bulbs have printing on the center of the surface... something that can result in uneven exposure on crucial areas of your print. Some of the more experienced printers here can give more precise replies, but it is also possible that regular light bulbs have a different colour temperature, or that their warm-up time is not as consistent as the real thing. On top of all that, I believe that enlarger bulbs are somewhat more robust than regular incandescent bulbs. Think of the dozens of times you may switch your enlarger on and off in a single session. I don't know that a regular light bulb would be up to the challenge.

Cheers,

 

[Removed Account]

I can speak from personal experience acquired with my first darkroom. Normal bulbs do work, although I'm not sure how long they would last. The printing on the center of the bulb can not only create uneven exposure, but depending on your focus it can even be readable!

 

[David A. Goldfarb]

Enlarger bulbs also seem to be more heavily frosted than regular bulbs. Some enlargers have parabolic reflectors that may require the filament to be in a certain location.

 

[Dennis S]

When I was using my old Omega I just used a 60 watt bulb with the writing taken off with an eraser and alcohol. Worked in a emergency but it couldn't handle the off and on scenario and they weren't frosted as much as regular enlarger bulbs.

 

[Ian Grant]

This is the 2nd thread in about a fortnight on these enlarger bulbs.

The specialist enlarger bulbs are often powder coated inside the glass to give a better spectral response and more even distribution of light. Some people still use these enlargers/bulbs for colour printing so consistency is important, although most people now use colour enlargers with Dichroic heads.

Using other bulbs you run a big risk of poor illumination particularly with uneven corners.

Ian

 

[Philippe-Georges]

Enlarger bulbs are not frosted but opal (important difference) and, in certain cases, of a well defined dimension with the filament on the right place being of a certain form (no zigzag for instance). They give the same intensity all along their rather short life, short life because they are 'over tensioned' (I do no know if this is the right expression in English, sorry), this is why they are so consistent in output. The inner bulb coating is told to be special too, but this I do not know for sure.
It never crossed my mind to use anything else than the right enlarger-bulb in my enlarger. I think that when these bulbs are designed, their must be a good and acceptable reason, for a non engineer tough...
I trust Philips, Osram and G. E. to know more about (enlarger-) bulbs than I do.

I pay 19 EURO for a bulb, Freestyle is cheap.

Philippe

 

[digiconvert]

There is also the point that it will soon be impossible to buy household filament bulbs in many parts of the world (EU and Australia have already gone this way I believe) . Not sure how economic it is to make these enlarger bulbs now, I would guess that the last production run has already taken place and that we are living on warehouse stock.

 

[AgX]

Voltage

The filament of that lamp has been designed that way that, relative to the similar houshold incandescent lamp, it is run on too high voltage.
Thus the part of photographically effective radiation is increased. With the disadvantage of, again in comparison with the household types, of a reduced lifetime. Which should not matter in amateur enlarging work.

The same technique has been employed in those (non-haloid) photo-lighting lamps.

 

[Ian Grant]

There is also the point that it will soon be impossible to buy household filament bulbs in many parts of the world (EU and Australia have already gone this way I believe) . Not sure how economic it is to make these enlarger bulbs now, I would guess that the last production run has already taken place and that we are living on warehouse stock.

I'm stocking up on enlarger bulbs for that very reason, although all my current enlargers use tungsten halide bulbs which are also being withdrawn.

Ian

 

[AgX]

There will be a market for spare incandescent non-haloid lamps: automotive being the biggest one.
I guess I it would not be that much of a problem for such a company to make a run of those classic enlarger bulbs.

(Having a machine at hand designed for those household types would be usefull though.)

 

[AgX]

I'm stocking up on enlarger bulbs for that very reason, although all my current enlargers use tungsten halide bulbs which are also being withdrawn.

Ian

That tungsten haloid lamp withdrawal is new to me.

 

[Stephen Frizza]

When my bulb goes, why can't I just replace it with a 75 incandescent? I'm sure there must be a reason. Freestyle wants $12 for a replacement bulb.

Your so freaking lucky!!!!Tthe replacement bulb in mine costs $690 excluding the shipping from italy! and sadly there is no substitute.

 

[Ian Grant]

That tungsten haloid lamp withdrawal is new to me.

They'll be around while older equipment still uses them but harder to find and will become much more expensive. They aren't energy efficient as they give out so much heat and so new lighting & equipment isn't supposed to use them. They are covered by the same EU directive as other light bulbs.

Phased out would have be a better word than withdrawn.

Ian

 

[Uhner]

Your so freaking lucky!!!!Tthe replacement bulb in mine costs $690 excluding the shipping from italy! and sadly there is no substitute.

$690!

Remind me to never complain on the price of 200w halogen bulbs…

 

[Phillip P. Dimor]

This 'pulling' of incandescent bulbs. Is it mostly over in England?
I'm finding less and less incandescent bulbs, except at dollar stores.
Had to order my last bulb from B&H, I should have ordered a couple as it sucks to be left with a blown bulb in the middle of a sessions.

 

[Ian Grant]

EU, UK and will be worldwide soon.

Ian

 

[bsdunek]

EU, UK and will be worldwide soon.

Ian

Right Ian. Here, the idiots in Washington are bent on taking away all our options in every area.

 

[Phillip P. Dimor]

I can't imagine anything working as well in my Omega D2.. sigh. Better stock up..

PS- Edison's original bulbs, the ones that used banana filaments amongst other things? Didn't those original ones last for decades? And that some sort of 'point of failure' had to be introduced in order to effectively sell bulbs? Please someone correct me if i'm wrong..

 

[AgX]

I'm finding less and less incandescent bulbs, except at dollar stores.

I can't see any major difference at the shops here. Though the variety of types, especially with the entrance of those LED ones in clasic fittings, is rising.

 

[srs5694]

Your so freaking lucky!!!!Tthe replacement bulb in mine costs $690 excluding the shipping from italy! and sadly there is no substitute.

What sort of enlarger (and bulb) is that? For $690 you could probably replace the whole enlarger, or at least build a new light source for the thing along totally different lines. (I'm thinking of people who've experimented with LEDs as enlarger light sources.)

 

[Ian Grant]

It's probably a bulb for a cold cathode head, some of these bulbs are partially hand made so expensive, I paid about £120/ $180 (US) about 15 years ago for a new one for a De Vere 504, they do last well though (usually), and are energy efficient as they are fluorescent tubes .

The EU have just started tackling other bulbs this week, household/domestic old style filement lamps have to be phased out by next year now they are looking at industrial lighting. Specialist bulbs will still be permitted but as types change & volumes decrease then some bulbs will rocket up in price.

Ian

 

[Spindleshanks]

I'm stocking up on enlarger bulbs for that very reason, although all my current enlargers use tungsten halide bulbs which are also being withdrawn.

Ian

Same here my partner thinks im crazy i must have around 18 of them now

 

[bill williams]

I've just in the last couple of weeks tried alternative bulbs in my Beseler 4x5 condenser enlarger and in my Beseler 6x7 condenser enlarger. This link http://www.lighting.philips.com/us_...g&parent=7593748565&id=us_en_products&lang=en will take you to a Phillips 70 watt halogena bulb that works very well in the two enlargers. I've even found that the color temperature difference between the halogena bulb and the PH140 bulb that is the norm for the 6x7 enlarger is practically nil. The output level is very close to a 75 watt bulb, but of course if you use a 150 watt bulb in your 4x5 you will experience a large level difference. And, the bulbs aren't cheap, but they are not 12 bucks apiece. In fact, I think at Home Depot they are about 8 bucks for two. There is no lettering on the business end of the bulbs, and I find that the halogena bulb gives me only a 1/4 of a stop fall off at the corners in the 6x7 compared to nearly a full stop of fall off with the PH140. I'm sure that is because the halogena bulb is about twice the diameter of the Ph140. I've not completely evaluated the halogena, but for now it looks to be my desired bulb for the 6x7. BE AWARE, there are a couple of styles of halogena bulbs, you want the HOUSEHOLD A TYPE BULB.

There are also a few 70 watt decorator bulbs made by GE that have the proper base and the globe is round instead of teardrop shaped. They also work, they are also found at Home Depot. I have the Beseler 6x7 color head that uses the ESJ bulb, but haven't found any replacement for it.

 

[Nicholas Lindan]

Edison's original bulbs, the ones that used banana filaments amongst other things? Didn't those original ones last for decades? And that some sort of 'point of failure' had to be introduced in order to effectively sell bulbs? Please someone correct me if i'm wrong..

Urban legend, I'm afraid. Right up there with the 200 MPG carburetor and "Black Helicopters" (Reg. TM of the UN).

If you under-voltage a light bulb it will burn forever. Ditto if the manufacturing quality control is so wretched that many of the bulbs never get above a dim yellow glow.

It is a false economy to run a light bulb so it doesn't burn out as it is then very inefficient at producing light: you are much better off using a properly rated lightbulb of a lower wattage.

A 2000hour 100W light bulb uses 200 kw Hr of electricity over it's lifetime - at $0.10 a kw Hr that's $20 worth of electricity. Compared to that the $0.75 cost of the light bulb is not significant. Efficiency is the name of the game, not the life of the light bulb.

If you run the numbers you will find the present every-day supermarket light bulb is highly optimized to provide the maximum lumen-hours for the minimum total cost of light bulb + electricity. The only reason to use 'long-life' light bulbs is if the cost of the replacing the bulb is high, as with very high ceilings.