I asked FLO this question:

"I have an older Baader UV/IR filter, item #2459220A, and I’m wondering if this ‘optimised’ one is going to be significantly better on my f2.2 RASA 11?"

...and their reply was

"...if you are having any particular problems with halos on some stars, reflections, or similar, a move to the updated filters could help, though without directly trying, it's difficult to say for certain. You'll be fully covered by the usual 30-day returns period if you decide to try one but see no improvement."

So I tried it (the 2" version), and I like it!

The previous version was giving very significant multiple reflections on bright stars. In contrast (sorry about the pun) this new one is not significantly different, in terms of halos, from a clear focusing filter. Visual inspection of the filter shows a striking difference: the old one appears glod-plated and is difficult to see through from the 'wrong' direction; the new one is virtually transparent with just the slightest sheen giving away its coating.

Works for me.

I make no secret about the earlier generation LRGB Baader filters that I use have always been a bit hit & miss with regard to the rejection of reflections on my C14 especially with the reducer. I think this has always been around cutting my cloth to suit and never really investing in the high end LRGB filters.

The L filter is especially problematic around calibration & every attempt with a panel produced a port hole in the image when the reducer was fitted. This clearly is a reflection issue with these earlier filters.

When Baader announced the new CMOS optimised filters I had high hopes that these could help cure the issue I was seeing however I did not want to take the plunge & invest in the full LRGB set until I had at least tested the most problematic filter, the L.

I ordered from FLO the Baader CMOS optimised UVCUT filter 50x50 mm square and it arrived within a week of order against a back order expectation of 2 weeks- so great service from FLO.

The new filters are very easy to orientate correctly as they have a black line indicating the direction the filter should be faced toward the telescope optics- this is a great improvement on the old" have a guess" which way.

I ran the same calibration procedure as the previous UVCUT filter and produced a new flat from this filter. I'm under Bortle 7 skies and the conditions are not good currently in my location with the lighter nights and no astro dark- only twilight.

I decided to test a new target with the filter, ABELL 2151, the Hercules cluster which is an action packed galaxy area and would be able to show the full field with lots of small fuzzies to give an indication of how the new filter performs on the entire sensor field of the ASI6200.

I have to say that the difference between the 2 filters is very apparent. The light ring from the reducer is very much reduced it is not perfect but is now at a level where post processing can easily remove the glow from the reducer in the middle of the field.

I'm really pleased with the new filter- it is a very substantial improvement & when the sky is darker in a couple of months it should produce great results.

I took a full set of data with both the new filter & the previous RGB filters however for this testing I was more anxious to process the UVCUT filter as that has always, for me, been the most problematic.

The image presented is 45 1 minute subs using the ASI6200 on a 3x3 bin & the C14 edge with reducer.

As always comments invited and I will be grabbing more data in this region as its really nice- I love all the fuzzies.

I will be ordering the RGB CMOS optmised filter set as I think these filtersbring an important gap between the mid & high end filters like Chroma or Astrodon.

The test image can be seen here https://www.cloudynights.com/topic/825434-first-light-baader-cmos-optimised-uvcut-filter/