Bulb frosting....

CDP930

Newly Enlightened
Joined
Dec 1, 2009
Messages
142
Location
Texas
I read a little bit about it, but can others share some experiences....dos and donts perhaps.

Looking into playing around with some bulbs, mainly for an Ultrastinger.

Thanks
 

Kestrel

Flashaholic
Joined
Oct 31, 2007
Messages
7,355
Location
Willamette Valley, OR
I've been very pleased with the technique. You've read this thread, right?

Poor man's surefire perfect beam

I've been using this technique recently on various Pelican bulbs up to the 3854-L, often on only the lower half, masking the top half of the bulb with masking tape. No bad experiences so far, although I suit up quite a bit before doing it (safety glasses, face shield, latex gloves inside leather gloves, lab coat) - I've been trained in chemical handling and have a lot of respect for the HF (hydrofluoric acid) in that chemical etching paste. 5 minutes of application time is plenty. Let the bulbs dry off for at least a day in a warm spot to make sure all moisture has gotten out of any potting compound.

BTW I've found that there is usually a considerable improvement in beam quality, but IMO beamshots make the improvement appear to be greater than it actually is since the brightness in the hotspot tends to oversaturate the camera for that region. While the hotspot doesn't become perfectly uniform 'inside', the shape of the hotspot does become considerably more circular. YMMV of course.
 
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CDP930

Newly Enlightened
Joined
Dec 1, 2009
Messages
142
Location
Texas
Thanks a bunch. I tried it and it did make the beam pattern much better.

I can see the loss of light I think. I left the top of the buld clear and gave a small ring down the rest of the bulb. Great little spot in the beam now and is mostly flood aside from the hotspot.

I will definately be trying this again.
 
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