I recently switched to ALP-T from L-extreme. One of the big issue with L-eXtreme is significant halo around brightstar.
On the other hand, ALP-T is doing well with halo suppression.
Seeing the images on Astrobin, L-enhance seems to have same issue. So, I am wondering if L-Ultimate solved this issue.
ASKAR 3nm seems to have good halo suppression looking at their test results posted on FB page.
Yeah recent Optolong were horrible with halos. Optolong also released 3nm narrow band filters past few months, and as far as I've seen there were no halos even on Oiii, maybe hopefully they 'cracked it'?
The ALP-T looks really awesome, but a cheaper filter with 3nm instead of 5nm sounds really really nice.
I didn't see enough from the Askar one to judge in my opinion, a good test would be something like Alnitak, Vega, Sirius, Arcrutus.
Anything besides that is a nice 'showcase', but far from being a real test to show how the filter handles halos.
Does the L-Ultimate, or any of the filters listed above, provide any advantage over the IDAS NBZ, which is already halo-free? I honestly thought the L-Extreme was rendered useless by it's issues with halos. Obviously lots of people are satisfied with it, but I much prefer the L-Enhance. While it may have wider bandpasses and doesn't block as much LP, it also produces a halo-free image. I was tired of spending most of my time in post trying to eliminate all of the halos generated by the L-Extreme.
I've been impressed by the images I've seen done with the NBZ and that will likely be my next filter purchase. If I wait a few weeks, will probably be able to get one used at a decent price from the people upgrading to the supposed latest and greatest.
I'm pretty sure the Antlia ALP-T Gold is superior in every way, 5nm, no halos, not sure about fast optics, whether it's relevant for you or not.
The NBZ is great, but with the ALP-T and the new 3nm duo band filters, I think it's no longer the best
L-enhance has much less halo then the L-extreme, but I don't like Hb in my OIII data.
A lot of manufacturers claimed things like "halo-free" in the product description of their filters and it turned out to be a lie. At least on very bright stars.
Let's wait for the real world tests.
Yeah, it's really hard to judge, honestly the only real halo-free filters out there are probably the Chroma/Astrodon ones, but recent brands are slowly getting there, the Antlia 3nm is amazing, and I personally had no halos(will probably have just a bit on the brightest stars).
This is the result Shawn showed in his video:
2 min exposure, but he also said that this is not the final version, so halos 'should' improve.