axby
Hello forum members,
I ordered two 150-watt Opal lamps, amongst other things, from F.
Two 150-watt Opal lamps (Dr. Fischer) were delivered.
I fitted the first Opal lamp delivered into my Durst M605 B/W enlarger.
After a short time, the first opal lamp burnt out, and the same happened with the second opal lamp.
Is it normal for such opal lamps to burn out after approximately 15 to 20 exposures each,
if you include the time taken to set up and focus,
i.e. after a total burning time (combined)
a maximum of 15 minutes, for such Opal lamps to burn out?
A cheap 100-watt bulb (and diffuser glass) that I am now using as a replacement has already
lasted many times longer.
I realise that a lamp for an enlarger is, in principle, a consumable part, but after
such a short period of use, they shouldn’t be breaking down yet.
Despite my polite email of 28 December 2013 and a follow-up
email on 3 January 2014 requesting a resolution, Company F. has not yet responded (but perhaps
a relevant member of staff is reading this).
I am still on the lookout for suitable opal lamps.
I would be grateful for any tips on which opal lamps are any good. Does any forum member perhaps have a
recommendation?
Many thanks for your help
axby
Urnes
That usually happens when the bulbs overheat. I’m assuming you checked beforehand that the bulbs were the right wattage. I experienced the same thing when I used a 100W bulb in my Leitz instead of a 60W one.
Regards, Sven
Bonderer
With such a short lifespan and two failing in quick succession, I’d suspect a faulty batch. But not responding to a complaint at all is really poor form. It might help to fit a voltage stabiliser in between. Best to ask a friend who’s an electrician; they can explain it better. It’s like switching on the light in the kitchen – usually nothing happens, but every now and then the bulb blows the moment you switch it on.
It’s the same principle with the enlarger and the opal lamps. Getting too hot? I’m not sure. Enlargers with opal lamps have always been bit of a hotbed, and normally the lamps should be able to cope with that. I’d also keep an eye on eBay and look for residues from the analogue era that keep popping up there. Osram, Philips or Narva – they used to be quite reliable. Alternatively, you could swap the transformer and switch to halogen, though sourcing the parts might be a bit tricky.
Urnes
Yes, if used properly, they won’t blow. But if you fit a 100W bulb into a 60W socket (which, of course, you shouldn’t do and which I certainly wouldn’t recommend to anyone), after about two minutes you’ll see little clouds of blue smoke coming out of the bulb and it will then blow. Hence the first question: can the Durst even handle 150W opal lights? The second question is then: how long does the bulb last when used continuously?
Regards, Sven.
jochen53
Hello, as far as I can remember, the M 605, when fitted with an opal lamp head, requires a 75 W bulb. The average lifespan should be around 100 hours of use, compared to around 1,000 hours for a standard general-purpose bulb.
axby
Hello,
The company F. has now got in touch and offered me a
solution that I’m happy with. Thanks!
€
For further information:
The Durst M605 B/W is designed for 150 W opal lamps.
€
Perhaps they were two ‘bad’ lamps after all
from the same batch.
€
I’m currently experimenting with halogen bulbs.
€
If anyone else has a specific recommendation for Opal bulbs,
please post it.
€
Regards, axby
