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L-Ultimate Under Full Moon

Optolong L-Ultimate Duo-Narrowband H-alpha OIII
8 replies•477 views
James avatar
James avatar
Hi everyone.

I was wondering what's your take on using the L-Ultimate under a full moon? 

​​My target will be about 45+ degrees away from the rising position.

Will I still get good Ha and OIII data? Or, am I wasting my time and should wait for another (rare) clear sky?
Well Written Engaging
Oscar avatar
Oscar avatar
I think you'll do fine getting Ha

but getting good OIII is harder when the moon is up

I would still try it; the Ha will certainly show, because I have done that myself with my 3nm filter and a moon near full
patrice_so avatar
patrice_so avatar
I agree with @messierman3000. With 45° to the Moon, I would go for it. Ha will be fine.
Dave Rust avatar
Dave Rust avatar
Moonlight has a wavelength of about 395 nanometers…not quite as blue as direct sunlight.

On the other hand, OIII is centered at about 500nm (blue-green)). And Ha is 650 and 700nm (red, right before infrared). So you should see definite rejection of moonlight with a filter that only allows OIII and Ha to pass.
Helpful Concise
Gilmour Dickson avatar
Gilmour Dickson avatar
I have used my ultimate with a bright moon many times.  Go for it.
Monty Chandler avatar
Monty Chandler avatar
The L-Ultimate and the Radian Ultra Quad-band are great filters for imaging with a bright moonlit sky.
Well Written
Dean Linic avatar
Dean Linic avatar
Few says ago I finally received my new L Ultimate and Askar Color magic D1, I will post single shots off 300 sec each. Just look at the brightest star!!
Askar remains in my RIG and Optolong is gone!!Optolong LUltimate.jpg Askar D1.jpg
Richard Mak avatar
Richard Mak avatar
It works quite well for Ha, but makes OIII quite noisy and weak (no surprises). Otherwise I'm happy with it, only limited halos around bright stars.

See a picture 4 days after the full moon -  24th August at 02:25. Single 300 sec exposure, R, G and B channels (screenshot from PI, not full res picture):
James avatar
James avatar
I was able to give this a test. Only had time for 54 x 300 second frames under 98% moonlight (no calibration frames) 

The L-Ultimate is pretty awesome to achieve this 👍🏽 

I'm going to add more data when I get clear skies again.

Thanks everyone 🙏🏽