Diatom imaged with 313nm light

Images made through a microscope. All subject types.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

jmc
Posts: 238
Joined: Fri Apr 17, 2020 3:14 am

Re: Diatom imaged with 313nm light

Post by jmc »

Smokedaddy wrote:
Fri Sep 16, 2022 1:33 pm
Care to share a few postings of your finalized microscope setup?

-JW:
Sure. The microscope itself is an Olympus BHB and it looks still pretty much as standard.

Light source - Zeiss 50W HBO mercury xenon (used for visible down to 313nm). Condenser lens replaced with fused silica. This gives me nice lines at 546nm, 405nm, 365nm and 313nm. for my recent work with 254nm I'm using a low pressure mercury lamp.

Field iris and auxillary lens - replaced with fused silica. The mirror below the field iris lens is standard (I measured the reflectance spectrum from it and it is good down to at least 250nm).

Condenser - antique Zeiss quartz one with top lenses for NA 0.85 and 1.25.

Objectives - range of different ones, including Zeiss Ultrafluars, Leitz UV, Zeiss monochromats, reflecting objectives.

Trinocular head - window at the base of it replaced with fused silica. Beamsplitter prism cut in two. One half remains so I can still use the eyepieces, the other half replaced with a block of fused silica. There are UV blocking filters in the eyepieces to add a level of protection, but I do not look down the eyepieces when I am using UV (focusing is done with live view on the camera for UV).

Photoeyepiece - a Lomo quartz one.

For safety, as well as the UV blocking filters in the eyepieces, I use a UV blocking filter on the field iris lens unless I am actively imaging UV. I also wear a pair of UV safety goggles all the time when the light is on.

I've written an article for the Royal Microscopical Society InFocus magazine which goes into the building of it in a bit more detail. If you want a copy of that, drop me a PM with your email and I send you a pdf of it.
Jonathan Crowther

Post Reply Previous topicNext topic