Zeiss 12v 100w Halogen Illuminator

75RR · Post by **75RR** » Thu May 05, 2016 3:05 pm

Just picked up Zeiss 12v 100w Halogen Illuminator to add to my 12v 60w Tungsten and my CREE XML LED (still fine tuning) and wanted to know what bulbs to get for it.

The Zeiss Catalogue recommends the 3800-59-1660 which I understand is the equivalent to the FCR.

Replacement Light Bulbs recommends the EVA

Anyone using either one or perhaps another?

These are the specs:

NOTE: There is a difference in the filaments which is not mentioned in these specs - CBAR6 for the EVA and C-F6 for the FCR
Not sure what the difference is.

NOTE: Found some additional info on the filaments (see highlighted lines)

Eddie · Post by **Eddie** » Thu May 05, 2016 4:20 pm

I have used both the EVA and FCR in my lamphouses and both work well. The EVA costs a bit more since it is rated to last longer.

75RR · Post by **75RR** » Thu May 05, 2016 4:24 pm

Many thanks Eddie - will go with the EVA then!

g4lab · Post by **g4lab** » Fri May 06, 2016 12:19 pm

In my experience the EVA and FCR will not necessarily fit all sockets. Their pins might be to large in diameter.

The rated life is almost irrelevant because it refers to being operated at exactly 12 volts and if you back off the voltage even slightly the the life will extend greatly. That is how they make the various lamps. Some have slightly larger diameter tungsten wire which draws more current and gives more watts.

I don't think you want the GY base , I think you want the G or GX 6.35. That is what fits all the Zeiss and Leitz halogen lamphouses which I have (which is pretty many) None of them use the larger pinned GY ceramic bases. I have those on hand too but they are for spectrophotometric light sources. You may be able to stuff the larger diameter pins into the socket but then it will never work correctly with the smaller pins. The sockets need to replaced every few lamps anyway because the higher temps at the pins of qh lamps oxidize the contacts and also anneal their temper and they become intermittent.

I like the 50 hour lamps because you can get higher color temps out of them. Just a personal preference.

When I get home from work I will look up the Osram and Phillips numbers I have on hand and post them here as an edit.

75RR · Post by **75RR** » Fri May 06, 2016 12:34 pm

Believe this is the bulb:

g4lab · Post by **g4lab** » Fri May 06, 2016 1:12 pm

It is also worth the trouble (imo) to obtain an Osram Xenophot labeled lamp. These are filled with xenon gas and allow the quartz halogen cycle to operate at a higher temperature so that you get an extra 50 degrees Kelvin or so color temp compared to lamps filled with krypton or argon.