Where to find these instant LED replacements?

[Scarodactyl]

Color looks pretty different at micro scale anyway. I've used neutral white XM-L2s in gem microscopes which have a CRI around 80 and the viewing experience with them is great. Still, I am pondering one of these 2x2 squares since one could almost certainly get away with the larger size in the much less demanding context of a stereo microscope.

[MichaelG.]

whether CRI is an appropriate metric is also arguable.

Can you suggest anything more appropriate ?
… CRI appears to be the ‘industry standard’ but I do realise that it doesn’t tell the entire [and very complex] story.

MichaelG,

[blekenbleu]

3mm should be fine that disc mount must be quite small

Sorry, image in reply #17 was a 16mm MCPCB with 35W LED that would be overkill to replace 20W halogen.
Here is a 3x3mm active area 18W LED on 16mm MCPCB:

xhp503hi-16mm.jpg (43.91 KiB) Viewed 1825 times

http://kaidomain.com/Cree-XHP50_3-HI-Ne ... D-5050-LED


https://blekenbleu.github.io/microscope/LED/

[blekenbleu]

Can you suggest anything more appropriate ?

The U.S. NIST recommends CQS for LED sources.
https://www.nist.gov/publications/ratio ... lity-scale
CQS seemed better than CRI for me with white LEDs and typical print colorants, 10+ years ago.
Whether differences are significant for transmissive illumination of typical biological samples
is outside my experience.

[essence25]

Hope this helps, I found the exact lighting system and lenses used in the Nikon E200LED MV R scope.
I'll disassemble the led mount to get to the actual led and see.

Can I swap that 3W led for a 5w in the same form factor? Also look at the driver board there are two led outputs the scope led goes into the small white socket which measures 5.1v there is a small black socket same size as the white one, on the opposite end which also puts the same voltage. It looks independent as if two led outputs/drivers on one board. The question is what are they using the black socket for? Is there a Nikon scope with dual illumination or 2 leds? (see bottom pic)

Here they are:
https://www.ledsupply.com/leds/cree-xla ... white-leds
https://www.carclo-optics.com/products/optic-10048





Driver

[Greg Howald]

Thanks for all the cool info