MicrobeHunter.com Microscopy Forum

Hi,

I'm looking for a LED ring illuminator for my Amscope SM-1TS stereo microscope.
Amscope has bewildering number to choose from, up to 144 LEDs. Do I need 144? Is less OK?
The are many identical looking rings available that cost less than the Amscope offerings. I assume they are all from the same factories.
Some reviews have complained about the light being too blue on some models. Has anyone here encountered this?
Lastly, recommendations would be appreciated.

Thanks,

Roger

144 LEDs should give you both more light, and more uniform light

Whether that’s important to you, I can’t say.

MichaelG.

Some are blueish but they're mostly fine, even the cheap ones are OK. It is fun to use cheap polarosing film to cut out a large ring and polarize the light thag comes off them and then attach a rotating camera polarizer to the scope so you can tune specular reflections.

Thanks for the input.
I decided to give this one a try: https://www.amazon.com/dp/B075MCNZFL?re ... tails&th=1

Scarodactyl wrote: ↑

Sat Jan 14, 2023 1:25 am

Some are blueish but they're mostly fine, even the cheap ones are OK. It is fun to use cheap polarosing film to cut out a large ring and polarize the light thag comes off them and then attach a rotating camera polarizer to the scope so you can tune specular reflections.

That looks interesting. I'll have to give it a try

Make sure the i.d. is large enough for your objective. That is a common mistake.
For somewhat more you can get one that will turn on any combination of quadrants, so you can get various oblique illumination arrangements. I paid about 80.00 for the one I bought and it is bright enough for l.w.d. situations too.

The nimber of leds is somewhat misleading because leds can have varying outputs. It is the total wattage that is important. 2 or 3 watts can be pretty dim at distance with some subjects.

The Bikani LED light ring works just fine. Doesn't appear bluish to my eyes.
It does hang down about 2 cm from the objectives.

If you play some more with the LED ring light at high magnifications, you may discover it is more blue than you thought and introducing chromatic aberration. Another issue, not explicitly raised in that thread, is that you may find its strong blue peak is reducing both the resolution and contrast at high magnifications. Below are a couple photomicrographs of a finely lithographed, 2732 EPROM taken with a Wild M7A and center-cropped to show the individual E-PL8 camera pixels. The first shows the EPROM cells under an incandescent ring light


and the second under an Amscope 144-LED, 6500K(?) LED ring light


I have lightly boosted (tinted) the incandescent image toward blue to bring it closer to the LEDs'. Despite doing that, the incandescent image has considerably better contrast and sharpness, I believe from the microscope misfocusing the LEDs' strong, blue peak.