Long Focomat v35 print times

[logan2z]

I’ve been using this enlarger for a few months and love it, I can’t imaging printing with anything else. One thing I’ve noticed is that I’m getting very long exposure times for many negatives, none of which are particularly dense.

I’m printing mostly 8x10 on Ilford Multigrade Classic FB paper and I’ve been stopping the Focotar 40mm lens down to f8. I’m getting print times in the 75-100s (!) range, which seems excessively long. As soon as I got the v35 I replaced the bulb with one of the aftermarket bulbs from replacementbulbs.com. I do know that some people have said that these replacement bulbs are quite a bit dimmer than the original Philips bulb so perhaps that’s the source of the long print times. Of course I could open up the lens to reduce the print times but I typically print at f8 so that I’m using the sweet spot of the lens and I have sufficient depth of field/focus.

For what it's worth, my prints look good so I don't think there's any sort of serious issue with the enlarger/lens, but I am wondering why my print times seem much longer than expected.

Has anyone else had a similar experience with the v35 and aftermarket bulbs?

 

[jimjm]

Does the bulb wattage meet that of the original bulb spec? Also, if the new bulb's angle of illumination is wider than the original, that will also be less efficient. Either way you'll see longer print times.

I don't have a Leitz, but my LPL dichroic enlarger uses a 100w bulb and can expose an 8x10 print of a really dense negative in under 60 sec @ f:8.

This page might have some useful information for you.

 

[darkosaric]

v35 and aftermarket bulbs

Yes. When my original bulb died, I got some no name bulb, and instead of 10 sec I was getting 60 sec. Nominal power in [W] was the same. Then I purchased 2 original bulbs from some company in USA that had old stocks (with shipping and customs I paid more than 100$, but that is life) - and it was back to normal fast times.

 

[Paul Howell]

I had a similar issue with an old Federal Stowaway 6X9 enlarger, it a diffusion type, but uses a clear bulb. The enlarger was made in the late 40s to mid 50s so when the bulb burned out I had to find a replacement. A 75mm frosted enlarger bulb worked in terms of even coverage but printing time were just too long, 45 to 60 seconds for prints that use to take 12 to 20 seconds. The dead bulb did not have any information as to how watts it was. I found a clear bulb on the internet, too slow, it was very dim and did not cover as well, some light fall off in the corners. After some experimentation I found that a GE 1140 LED bulb works, at least with grade 1 to 3 filters. This bulb also work in my D3 and Meopta enlargers. I rarely print higher than grade 3.

 

[Ron789]

I had the same experience with the V35 and replacement bulbs. For me that was the main reason to sell it and replace it with a Focomat 1c and LED bulbs.
You may open the lens to F/5.6 or even F/4. I did some tests and found that F/5.6 performs equal to F/8, and F/4 is only marginally less, only in the corners.

 

[logan2z]

I had the same experience with the V35 and replacement bulbs. For me that was the main reason to sell it and replace it with a Focomat 1c and LED bulbs.
You may open the lens to F/5.6 or even F/4. I did some tests and found that F/5.6 performs equal to F/8, and F/4 is only marginally less, only in the corners.

Thanks for the info. The v35 manual does say that f5.6/f8 are optimal for the Focotar so I'll try some prints at the larger aperture. The longer print times aren't really an issue for me - lots of time to dodge but I was curious to hear if this was a common experience with the v35 and aftermarket replacement bulbs and it sounds like it's fairly common.

 

[logan2z]

Does the bulb wattage meet that of the original bulb spec? Also, if the new bulb's angle of illumination is wider than the original, that will also be less efficient. Either way you'll see longer print times.

The wattage is the same, 75W. I don't know what the beam angle is of the new bulb, but it may be larger than the original Philips bulb which may be contributing to its diminished output.

 

[Renato Tonelli]

If you are ready to plunk down some 'serious money', you can retrofit it with an LED unit made by Heiland Electronic (Germany); you won't have to worry about any lamp/bulb changes again.

https://heilandelectronic.de/led_leitz_v35

...yes, it's expensive.

 

[logan2z]

If you are ready to plunk down some 'serious money', you can retrofit it with an LED unit made by Heiland Electronic (Germany); you won't have to worry about any lamp/bulb changes again.

https://heilandelectronic.de/led_leitz_v35

...yes, it's expensive.

Thanks. As luck would have it, I just stumbled upon a batch of new old stock Leitz 13139 bulbs and scooped them up. If for some reason those don't improve things then I'll take a closer look at the Heiland LED unit.

 

[choiliefan]

Strictly for fun you could check the output of your power supply.
It may not be putting out full voltage anymore.

 

[logan2z]

Strictly for fun you could check the output of your power supply.
It may not be putting out full voltage anymore.

That's worth a shot.

 

[ericdan]

I have a 150W bulb in my focomat 1c and that’s too strong. I get very very short print times. Around 4-6 seconds at f/16 on 5x7 paper. I just ordered a 75W bulb from B&H