My first test with M42 in a 120mm refractor was impressive. The background skyglow (Bortle 6) was noticeably reduced making the nebula really pop.
Fainter objects were more of a struggle, until I switched to a 200mm Newtonian. Wow. M27 and the veil nebula were much more apparent than without the filter. My final tests were with a 200mm SCT which were similar to the Newtonian.
So yes, the filter works well, but you may well need a decent aperture/mirror to get the best from it.

Due to numerous reasons I've only used this filter a couple of times and only on the Orion Nebula, however both times I have been blown away by the detail I've seen. I've never seen so much fine wispy detail in the nebula before, absolutely blown away by it. I've only used it with my 4" Esprit 100 so far and I am really looking forward to seeing how it performs with a larger aperture. If you're thinking about getting one of these then don't think about it - get it!

I would thoroughly recommend 1 1/4" Astronomik UHC visual filter. I tested it on on the Dumbell nebula through an 8mm Televue Delos EP + 8", F6 Dobsonian + Hilux mirror coating (got to squeeze it to the max after all!). Location: Rural, Time: July, Midnight+. The Moon was setting and the object was high in the sky. The filter very effectively darkened the background and the nebula stood out nicely (almost a 3D effect) with some structure visible.
Likewise for the Ring nebula, however as this remained relatively small in the 8mm EP, it just appeared brighter - still an excellent result.
I don't want to overstate the improvement as all the visual gains that we make are marginal, but they all add up and I'm pleased to have this filter in my optical inventory.

I have only had the chance to use this item once so far. I viewed m42 with it under a full moon and although seeing conditions were far from ideal it popped. A lot of structure was seen in my 8" SCT.

I have previously tried several of the cheaper UHC filters and wasn’t really impressed. However this changed when I upped my game and bought the Astronomik UHC. The contrast benefit is immense and I’ve spent hours observing targets i used to glance over. I’ve learned that i should have bought this straight out rather than wasting my time and money on sub par filters

Amazing filter. Would recommend for those who are just starting out as I am. Used on the moon, the colour what the filter did was amazing. Definitely will purchase again from FLO. Fast delivery great service 100% +++

Simply the best filters out there in my opinion. I've the Astronomik OIII, UHC and H beta. Not the cheapest, but when you factor in time and money spent on your scope, getting to a dark site and then not being able to see some faint DSO as well as you could (or not at all) because your filter isn't up to spec, then they are worth every penny. It's frustrating if you can't see something faint and elusive, then wondering if it's your filter, seeing conditions, scope alignment, etc. With Astronomik filters you don't have to worry about that being the issue. Good resale value as well.

I put this filter on to a 10mm eyepiece after finding the Orion nebula and it made a big difference. Would definitely recommend.

Excellent service as usual from FLO.

I owned a couple of "cheaper" UHCs before eventually moving to Astronomik. I should have saved some money and got the best to begin with! This filter provides lovery starry views of many night sky nebula and it is a regular in all my scopes.