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John Hothersall
03-09-2018, 06:14 PM
SPX350 F9.1 with 2xPowermate. ASI290, Baader RGB, Astronomik UHC.

NGC 7009 the Saturn nebula is my best image yet in good seeing. It is so bright in the ASI290 I used short subs for lucky imaging.

IC 1297 is an inconspicuous small planetary between beta Corona Australis and alpha Sagittarii.

IC 4634 is a strange planetary in Ophiuchus pretty faint shaped like an 'S' or meat hook.

Minkowsky 2-9 the butterfly nebula in Ophiuchus looks almost perfect but was also faint in the preview.

Regards, John.

Geoff45
03-09-2018, 07:13 PM
Stunning images a John. Great view of the Saturn nebula. What was the length of your short subs?

cometcatcher
03-09-2018, 10:48 PM
The Saturn Nebula is fantastic! The others are cute too.

John Hothersall
04-09-2018, 05:30 PM
Thanks for the comments.

The subs I tried first where 1/4sec and the green was still bright so I settled on 1/2 sec with lower gain of 570 instead of 600 which brought down the noise/brightness really well.

I did another lot of exposures of 1sec for extension halo detail.

John.

Prickly
04-09-2018, 07:43 PM
Super good images. The detail in Saturn nebula is incredible.

The ASI 290 looks to be a great camera-Is your camera cooled?

Great effort for tricky objects and the stars look great.

Cheers
David

John Hothersall
04-09-2018, 08:20 PM
Hello David, I did consider the cooled version but the best images came from uncooled ASI290 quite often, so I got the uncooled monochrome which requires no darks, I stack the ser file using Registax.

In summer the ASI temp is 29 degrees with few faint warm pixels and in winter at 15 degrees no warm pixels with exposures no longer than 3secs. I considered a DIY peltier to cool by 20 degrees further but it is not needed.

Exposures greater than 10sec would benefit in summer from cooling.

ASI is a great all round introductory camera, although it is only 12 bit. It is designed for planets but I am experimenting with bright deep space objects.

Regards, John

troypiggo
04-09-2018, 09:06 PM
I really enjoy your planetaries. I wonder how my 10in reflector (1200mm FL) would go with ASI120MC. Might need powermate. So you shoot video still as you would planets? Capture in Firecapture and process in Autostakkert etc?

Ryderscope
04-09-2018, 09:52 PM
A great application for your specific configuration John resulting in a nice collection of PNs.

John Hothersall
04-09-2018, 11:08 PM
Yes Troy 16 bit binx2 usually as a ser file in sharpcap or firecapture but I use Registax and Photoshop to process, I have not tried Autostakkert. With globulars I can collect 2000 frames and stack the 500 sharpest in RegX. You can used fits if you prefer.

Your 10" and 120 would be great for bright nebula like m42, swan, triffid, PN's like saturn neb, ghost of Jup, and any bright globular like omega cent, m4, m22, m55, 104. Galaxies are difficult but sombrero has the highest surface brightest and worth a look, but with colour 120 it may be too faint?

You can use native fl+ coma corrector or just 2xpowermate with bin or full resolution to suit seeing+brightness. Images are quickly taken in an hour with short subs and no breeze.

John.

Atmos
05-09-2018, 06:40 AM
Exceptional images John, very well resolved!

multiweb
05-09-2018, 07:04 AM
That's a superb gallery, John. #1 is a stunner. :thumbsup:

Paul Haese
05-09-2018, 04:05 PM
Nice images John. I reckon the Saturn Nebula is the best by a country mile. Love the detail.

topheart
09-09-2018, 11:35 AM
Good work!
Cheers,
Tim

Camelopardalis
09-09-2018, 10:19 PM
Cracking shots John :thumbsup:

Ross G
10-09-2018, 09:39 AM
Great looking photos John....I love the Saturn Nebula!


A very intersting capture technique.


Good luck.


Ross.