Leitz Focomat 1c enlarger light bulb size and type

[Edubarca]

Hello my friends, Greetings from Colombia.

I am preparing my recently purchased Leitz Focomat 1c enlarger. It is almost ready but I would like to know what type of light bulb including size I can use. Since it is difficult nowadays to find a traditional tungsten bulb, What would you recommend me which does not costs a fortune and it is easy to find it locally? Thanks very much!!

 

[Patrick Robert James]

Depending on which 1c you have, the tall housing or the regular housing, different bulbs are recommended. You are supposed to have a short neck bulb for the short housing, but I just use a regular one. A PH 211 will work fine. Just pull it all the way up before you lock it in. Or if you have a meter, check where it gives the most even illumination. I just pulled mine all the way up and it works fine.

Some people have had luck with LED bulbs which you can find locally. If you want to go that route, make sure the light is even over the surface of it. Some bulbs have writing on them as well and you don't want that. You also need to look at the color temperature of the bulb. There is a thread here that had a recommendation so if you want to go that route, you should look up that thread.

I use an LED bulb when I am adjusting the Focomat. They don't get hot so it is perfect for that. I can just leave the light on while I am doing it. I haven't tried printing with it yet, but I probably won't.

Easiest thing though is just get a PH 211.

Hope that helps!

 

[Edubarca]

Hi Patrick, thanks for your reply. First of all, I have no idea if it is a tall or regular housing. Can you tell me the difference? Secondly, a 70w standard bulb can be used? What would be a replacement in LED bulb? watts? size? Yes, LED bulbs are available here so if you can give me more precise information, I can get the bulb I need. Thanks a lot!!
EDUARDO

 

[Edubarca]

I have just found out a locally available 75w bulb but with transparent, not frosted glass. Can this be used?

 

[AgX]

incandescent enlarger bulbs are

-) opalized (milky coating, not just frosted)
-) wihout labelling at the top
-) voltage overrated

Which make them different from household bulbs. Though the overrating may be considered of lesser importance.

In Germany only pear-shaped bulbs were used, with E27 thread and with two bulb diameters depending on rating.

(In higher voltage they are still manufactured.)

 

[AgX]

If you tell us your mains voltage we could advise you a dealer.

Some dealers offer different, but likely usable bulbs.

 

[Edubarca]

Colombia is the same as the United States: 120 volts. Thanks

 

[AgX]

This one would be a good fit:

https://www.bhphotovideo.com/c/product/74800-REG/Wiko_PH211_Lamp_75.html

(E26 threads fit into E27 bases)


If you want to buy locally you would have to look for such opalized lamp in its houshold version. Such would not be overrated and would have a labelling at its top that you must wipe/grind of. In your part of the world such lamp might be smaller and shorter. But likely would work too.

In any case the lamp must moved and oriented by tje rod the fixture sits on, until there is an even lighting on the baseboard,

 

[BMbikerider]

If the bulb of whatever type has writing on the glass facing the condenser, this will have absolutely no effect what so ever. If you think when you focus a negative onto the baseboard, anything outside a range of perhaps 3mm each side of the negative holder , be it glass or glass-less will be completely out of focus and of no consequence.

I use an LED bulb with the E27 thread and a rated colour temperature of 6500 Kelvin, as a guide to obtaining a correct colour balance when printing RA4. This bulb is roughly the size and shape of a 75w 230v bulb. I think the U.S. use 110-120 volts as standard, but I am certain there must be an equivalent in that voltage as the one I use.

If I remember correctly with the Leitz Focomat 1c there is a facility to raise or lower the bulb to secure the optimum distance from the condenser. Using an LED bulb in a Focomat, I think would be a very good move. They don't get hot so the possibility of the negative 'popping' will be virtually eliminated.

This LED bulb I use consumes 14 watts, but has the rated output of 80 watts and would work very well in the Focomat. With the raised colour temperature this will alter any accurate multigrade filter value, but not by much and you would probably only loose half a grade at the soft end of the scale.

 

[Edubarca]

Hello my friends. Thanks you all for the information. I'll try to find the bulb locally. I am almost sure I will find it and make the necessary tests. If not, I will order from BHphotovideo.
I appreciate your help.
EDUARDO

 

[AgX]

Another attempt could be using a frosted bulb and using an added ground glass as diffusor.

 

[Saganich]

I have just found out a locally available 75w bulb but with transparent, not frosted glass. Can this be used?

There can be no markings on the bulb as they will be projected. The bulb socket can adjust from the post where the cord emerges. Pull it up all the way put in bulb and check for evenness in the light field. Mine is up all the way with regular size 75 watt. I found 100 watt to be too much except for large prints.

 

[AgX]

Thus this mean you are using a clear, unfrosted bulb?

 

[Edubarca]

No, I am not. I thought I couldn't find frosted bulb but I did find several so I think the bulb problem is solved!!

 

[Edubarca]

But I have more questions and concerns. Please check the photos

. Can you help me with this issues?

 

[AgX]

-) my question regarding the use of a clear bulb was directed at member Saganich.

-) that thing is a lock to arrest the enlarger head, as the head can be swung back to give access to the film stage.

-) that hole on the baseboard was intended as hole for a mains cable, leading to a mains socket mounted just on top of it and intended to feed a specific Leitz accessory.

 

[Edubarca]

-) my question regarding the use of a clear bulb was directed at member Saganich.

-) that thing is a lock to arrest the enlarger head, as the head can be swung back to give access to the film stage.

-) that hole on the baseboard was intended as hole for a mains cable, leading to a mains socket mounted just on top of it and intended to feed a specific Leitz accessory.

Thanks. What specific leitz accessory are you referring to?

 

[AgX]

A magnification scale. It was illuminated by a bulb and thus needed mains feed.

 

[Edubarca]

Another question. can you help me how to organise the connections that I found under the enlarger base after removing the black cover?

 

[Saganich]

-) my question regarding the use of a clear bulb was directed at member Saganich.

-) that thing is a lock to arrest the enlarger head, as the head can be swung back to give access to the film stage.

-) that hole on the baseboard was intended as hole for a mains cable, leading to a mains socket mounted just on top of it and intended to feed a specific Leitz accessory.

Can't use clear bulb because the filaments will project as well. A well frosted as was suggested in posts.