I recently received a Mod3C unit from TNVC - ordered about 6 months ago. I’m very happy with the specs which met and exceeded what I requested. Last weekend I got out to a bortle 3 dark site and was blown away with the views. I was using it afocal in my 16” f4 with a 7nm H-alpha filter and was in nebula heaven. I think I made some of the club’s imagers into night vision converts.
The only annoyance is a dark spot in zone 2. The spec sheet shows 0 dark spots in any zone however when viewing 1x unfiltered it’s clearly visible. I emailed TNVC and they said anything under .003 doesn’t show up on the spec sheet and is considered peppering. I find myself really liking 1x unfiltered from my light polluted backyard. But I keep getting distracted by the dark spot. Maybe it’s not really a big deal and I’ll eventually tune it out. Maybe it’s just dust between the tube and lens? It’s not on the ENVIS lens or on the surface of the eyepiece lens. The picture below shows the dark spot at 9 o’clock in zone 2. It’s a lot more noticeable in person than in the photo. Just wondering if you all think this looks like what a dark spot under .003” looks like.