StarTools

With the continuing La Niña weather pattern present down under , imaging is becoming more difficult due to rare clear nights and clear nights interrupted by intermittent cloud.
Thankfully this La Niña weather pattern is suppose to neutralise by late December/ early January

Captured NGC 2070 Tarantula Nebula which is located in the Large Magellanic Cloud , a satellite Galaxy to the Milky Way. Unfortunately the capture was interrupted by cloud again so only managed half an hour of data

NGC 2070 Tarantula Nebula
Magnitude 8
Distance from Earth 160,000 light years
NexDome Obs
Bortle 3 , waxing Moon
8” f5 GSO Newt
Skywatcher EQ6-R pro mount
ZWO2600MC cooled to -10C , Gain 0
Optolong L Extreme filter
Only 10 x 3min subs
No calibration frames
Stacked in DSS ( Average )
Processed in Startools v1.8
Compose
Bi Color OSC
Colour Style Scientific
Matrix SHO 4th
Only binned the image to 71%
Again SV Decon worked beautifully on this image

Very pleased with the level of detail considering on 30 mins of data. Image was quite noisy so had to keep a lid on the stretch in AutoDev by reducing the ROI and using Gamma and Shadow linearity

Comments most welcome
Thanks

That's very nice for a quick hit and run. 30 minutes!

I just did a quick IC 1805 last night, mostly as a first test of a number of new things including my new collimation kit, with a total of 75 minutes. 25 for each NB filter.

I dithered every 5 minute sub, used darks (though maybe stale as they are from July?), first tried average and then sigma rejection despite the number of subs, but still could not avoid little splotches of dancing hot pixels.

Oh well. It was just a test.

Hi Mike,
Thanks for your reply
I assume you have an f4 Newt ?
I’m not game enough to go f4 , f5 and f6 is easy to collimate and also holds collimation quite well. I just use a Cheshire and follow up with a laser , collimated in a few minutes.
A lot of folk who use refractors cringe at the thought of collimating a Newt but it’s no big deal. In fact my 10” f5 Carbon Fibre newt is the easiest of all my Newts. It holds collimation incredibly well compared to my metal tube Newts.

Cheers
Martin

Thanks Martin,

I think my lack of ease has less to do with the f4 speed and more to do with cheap(-ish) GSO based Newt.

The primary is smooth and easy. The secondary is hard. Movement with the three tilt screws (replaced with Bob's knobs) is hard, both physically on my fingers and as predictable movement. I've already modified the three-leg style mirror holder with a big metal washer, dimpled with a drill, and a milk jug plastic washer, for rotation. That helps, but not enough.

Maybe if the tilt screws had nylon tips?

So with movement difficult like that, it is thus correspondingly difficult to get both a round secondary in the sight tube, while also pointed at the primary center spot. I can readily get one or the other but not both, without a lot of attempts. The whole combined tilt rotation error is just hard for me to think through and correct out, albeit better now that I have proper tools.

I do keep things fairly tight, and once set, it does hold in place quite well, so it's just a matter of obtaining proper collimation in the first place.