Robert_T
16-02-2021, 09:13 PM
Finally after more than a week of rain and cloud I managed to get my new APM LZOS 130mm refractor mounted up, polar aligned and ready to go.
Chose a familiar and well placed subject, the Eta Carina Nebula for this first run. Full res version https://www.astrobin.com/full/c3vcip/0/
To say it was a frustrating first night is an understatement. My autofocuser (Sesto Senso 2) is slipping badly on this new scope focuser such that I kept chasing focus but never found it. I spent several hours trying different settings and tweaking the focus tensioner all to no avail. I've two Sesto Senso 2 focussers and used these on both Espirit 100 and Askar 400 without this problem. I've remounted today and tried at different elevations and think it's improved though i'm still getting some slippage.
Anyway, last night in the end I had to resort to (horror) manually focusing which I'm not well setup for and did very roughly (took exposure, looked and tweaked then took another etc - never got live view to work with this camera) so focus while not bad is not perfect either.
This is 4 hr and 22min integration from around 6 hours of 2min subs. None lost to cloud for a change, but some poor seeing and while my guiding seemed ok (0.5 to 0.8 arc sec on ave) things a little more critical at this 780mm compared to my espirit 100ed at 550mm so discarded a few "eggy" ones.
Stacked in APP as Ha-OIII mono for luminance, Ha extract for red, and OIII extract for green and blue then recombined in Startools and finished in PS.
I'm happy with the optical quality as far as I can tell (very nice defocussed stars with evenly illuminated rings either side of focus). My flatenner spacing looks pretty close...prob needs 0.5mm either way. If I could just sort out the focusser issue I would be golden!
Chose a familiar and well placed subject, the Eta Carina Nebula for this first run. Full res version https://www.astrobin.com/full/c3vcip/0/
To say it was a frustrating first night is an understatement. My autofocuser (Sesto Senso 2) is slipping badly on this new scope focuser such that I kept chasing focus but never found it. I spent several hours trying different settings and tweaking the focus tensioner all to no avail. I've two Sesto Senso 2 focussers and used these on both Espirit 100 and Askar 400 without this problem. I've remounted today and tried at different elevations and think it's improved though i'm still getting some slippage.
Anyway, last night in the end I had to resort to (horror) manually focusing which I'm not well setup for and did very roughly (took exposure, looked and tweaked then took another etc - never got live view to work with this camera) so focus while not bad is not perfect either.
This is 4 hr and 22min integration from around 6 hours of 2min subs. None lost to cloud for a change, but some poor seeing and while my guiding seemed ok (0.5 to 0.8 arc sec on ave) things a little more critical at this 780mm compared to my espirit 100ed at 550mm so discarded a few "eggy" ones.
Stacked in APP as Ha-OIII mono for luminance, Ha extract for red, and OIII extract for green and blue then recombined in Startools and finished in PS.
I'm happy with the optical quality as far as I can tell (very nice defocussed stars with evenly illuminated rings either side of focus). My flatenner spacing looks pretty close...prob needs 0.5mm either way. If I could just sort out the focusser issue I would be golden!