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Hi y'all just wanted to share this overkill of a lighting modification to my Laborlux 12.

This unit was purchased with no power supply or any type of lighting for that matter, I considered the retro-diode option but for me that was just too easy and wanted the hands on.

Here's Stage 1
Thanks to the recommendation of a member on FB Amateur microscopy, I decided to use a 55W 5000K Xenon HiD bulb from a car lamp for the reflected lamp, this is being powered by a...
Henxlco AC 110V - 220V to DC 12V Regulated Transformer Switch Power Supply 10A.
Again I can't take credit for this, the idea was pure genius.

For the transmitted light, I could not find an original lamp that was relatively cheap so I decided to use a Leitz 05260 power supply with a 12V 100w halogen bulb that is mounted to the base.....

I don't plan on using the whole max voltage on the 100W bulb, since it puts out a lot of heat and theres not a lot of ventilation on the base.

The xenon bulb is being held and centered using ......the rubber gasket from the valve cover of a Honda engine., Turns out it was the perfect fit (diameter for the leitz lamp) and heat wont be a problem.

I decided to mount the HID ballast on the outside of the panel box ( gets really hot)....until I can permanently mount a 60mm cooling fan on the side of the box.

100W bulb.

Clever title.

Is that a Xenon emission lamp up top? If so, it will be going a bit deeper into UV. Nice for some fluorescence work. Probably worthy of adding a bit of barrier protection for the eyes. I do like the idea and your implementation.

Down below, not sure the internal location has enough cooling for a 100 watt tungsten halogen bulb? Might want an IR filter and arrange for cooling? Leitz normally mounts a 20 watt bulb outboard with an IR heat-blocking filter in the path -- along with a condensing lens after the lamp and a reflector behind it. The 100 watt housing mounts the bulb still further outboard, with lots of baffled cooling vents.

There's also the consideration of tungsten halogen bulb life if the voltage is turned too far down - with some provision for neutral density filters. Crossed polars on the field lens would be one option once heat and illumination issues are OK.

PeteM wrote: ↑

Thu Oct 21, 2021 8:40 pm

Clever title.

Is that a Xenon emission lamp up top? If so, it will be going a bit deeper into UV. Nice for some fluorescence work. Probably worthy of adding a bit of barrier protection for the eyes. Do like the idea.

Down below, not sure the internal location has enough cooling for a 100 watt tungsten halogen bulb? Might want an IR filter and arrange for cooling? Leitz normally mounts a 20 watt bulb outboard with an IR heat-blocking filter in the path. The 100 watt housing mounts the bulb still further outboard, with lots of baffled cooling vents.

I believe its a Xenon bulb, the person that recommended this modification, says he normally removes the outer glass shell of the bulb, since it filters most of the UV light. My first attempt using a Dremel tool and a pair of pliers was not very clean, but it works. A pair of bulbs is $14 usd...a lot cheaper than the $237 I've seen on medical sites

For protection I'm using some Ansi z87.1 googles, but would love to add a plexiglass or some type of shield. Any ideas on where I can find some or material I can use?
I also made a light catch trap similar to the one Leitz used to sell for the Laborlux

The IR filter would sit on the light path? Would one of fleabay do the job?

Polycarbonate is a far better UV filter than acrylic (Plexiglas). Welding supply places will have protective lenses - basically cheap flat pieces of clear polycarbonate meant as a protective layer of the darkening filters of a welding helmet. I'd be inclined to buy a name brand, where the UV transmission spectrum has been spec'd.

I'm not qualified to give you complete advice on this, but I'd surely have a good UV filter in the path to the eyes. And another to catch light reflected from the stage.

FWIW, I once bought some cheap UV camera filters out of China to use as a safety precaution for LED lights. When tested with a spectrometer, turns out they were basically clear glass - not actual UV-filtering glass.

To add, on the safety goggles - the ANSI spec doesn't require UV filtering. If present, it does provide a "U" scale that ranges up to "6" with that being the best protection.

On IR filtering, my spectrometer doesn't go very far into the infrared and I haven't been able to test cheap Chinese filters. The name brand ones like Schott and others, sometimes available on Ebay, will have specs you can trace. I've bought some name brand ones on Ebay as replacements and they're working OK -- no broken condensing lenses further down the line due to excessive IR and heat.

PeteM wrote: ↑

Thu Oct 21, 2021 9:12 pm

To add, on the safety goggles - the ANSI spec doesn't require UV filtering. If present, it does provide a "U" scale that ranges up to "6" with that being the best protection.

On IR filtering, my spectrometer doesn't go very far into the infrared and I haven't been able to test cheap Chinese filters. The name brand ones like Schott and others, sometimes available on Ebay, will have specs you can trace. I've bought some name brand ones on Ebay as replacements and they're working OK -- no broken condensing lenses further down the line due to excessive IR and heat.

Im glad you brought that up, I'll make sure to use it via the camera lenses/ comp monitor until I can get a proper shield and googles, as well as that IR filter.
In the case of the IR filter, would It go just mounted on the light path?

Plasmid wrote: ↑

Thu Oct 21, 2021 9:20 pm

. . .
In the case of the IR filter, would It go just mounted on the light path?

I'd briefly test what you have for transmitted illumination. With no condensing lenses in front of the bulb, 100 watts vs. the usual 20 watts, no reflector, and the inboard location (no space for ND filters and likely excessive heat) you may decide you want something closer to the OEM configuration.

If you still get even Koehler illumination, there's not too much heat in the base, and the lamp isn't so bright you have to turn it down (bulb life plummets) too much - then, yes, the heat filter should be spaced a bit after the filament (well cooled both sides) and before any other optical elements. It's not a miracle cure, but can reduce heat damage to other optics and eventually to specimens. In poorly designed systems, or ones with a missing or cracked heat filter, the next condensing lens in the illumination system is prone to thermal expansion and cracking.

I'd guess you may want to move the bulb outboard, figure out some sort of condensing system, add a reflector, and then have an IR filter and perhaps a diffuser in line before the field lens.

FWIW, the Leica 20 watt lamp housings can be had on Ebay for around $100. 100 watt ones maybe a bit more. The 20 watt ones are bright enough for most work, except maybe taking pictures with high power (60-100x) darkfield, phase, and DIC. A flash adaptation could solve that. 20 watt housings missing the bulb socket show up at less than half that cost and might be a good candidate for your own conversion? At least then, most of the heat is headed up and away from the microscope base.