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Peter Ward · #1 06-04-2022, 11:36 AM

OMG clear skies in Sydney...what a rarity.

I took the fleeting opportunity to refine the spacing/tilt of my QHY600M system....and while the optical-mechanical side of things was excellent,
FWHM's looked tight. (note the bright binary star center top, just above the dust lane...nicely resolved).

Ridding images of the dreaded low-level CMOS banding still proves to be problematic for me.
Clouds slowly rolled in to terminate this session, hence no colour data or different USB traffic settings (apparently a fix) was possible. No decon applied
with the image resampled for the web to just under 25% of native resolution.

Results are here

gregbradley · #2 06-04-2022, 12:33 PM

On first look it appears to be a super image. But on closer inspection (pixel peeping really) stars are quite eggy so tracking was off?
Top part of the image the fainter stars look out of focus.
1x1 binning is not the way to go with long focal length. 2x2 will be more forgiving and a tad better QE. I got round stars to the corners 2x2 fairly easily.
If you think the QHY is trickyto correct for tilt spare a thought for the ASI owners where little attempt is made at the factory for sensor orthogonality.

As for banding, long enough exposures plus dithering seems to handle it. Also high gain reduces it but yes CMOS is not necessarily a golden egg in all ways.
Not selling my CCDs yet!

Greg

Peter Ward · #3 06-04-2022, 01:06 PM

Quote:

Originally Posted by gregbradley

On first look it appears to be a super image. But on closer inspection (pixel peeping really) stars are quite eggy so tracking was off?
Top part of the image the fainter stars look out of focus.
1x1 binning is not the way to go with long focal length. 2x2 will be more forgiving and a tad better QE. I got round stars to the corners 2x2 fairly easily.
If you think the QHY is trickyto correct for tilt spare a thought for the ASI owners where little attempt is made at the factory for sensor orthogonality.

As for banding, long enough exposures plus dithering seems to handle it. Also high gain reduces it but yes CMOS is not necessarily a golden egg in all ways.
Not selling my CCDs yet!

Greg

Thanks for your input Greg....but I beg to differ on the eggy stars (abberation inspector version attached).

Some stars are indeed eggy, but the effect is not global and I suspect that is because they are unresolved binaries.

There is some flaring toward the right of frame (tilt/collimation/spacing/who knows) but...meh...it doesn't leap out at me....

but agreed....not quite there yet....more tweaks required.

multiweb (Marc) · #4 06-04-2022, 02:00 PM

Awesome shot Peter.

: The colour should be fantastic.

Peter Ward · #5 06-04-2022, 03:29 PM

Quote:

Originally Posted by multiweb

Awesome shot Peter.

: The colour should be fantastic.

Thanks Marc. I was comparing this L data to my earlier efforts. Much tighter stars..

Colour would be nice..plus some clear skies!

Dave882 (David) · #6 06-04-2022, 03:34 PM

Beautiful resolution in the dusty core and yes very tight indeed. Eggy stars or not this is spectacular!

h0ughy (David) · #7 06-04-2022, 03:58 PM

Ahh who cares about eggy stars you got some photons , how rare is that .

Startrek (Martin) · #8 06-04-2022, 06:21 PM

Peter,
Another superb image with remarkable resolution and detail !!
Not all stars are perfectly round ?
I was out that night too ( Sydney south suburbia ) with my little Newt on the same target but my guiding was struggling with a decent guide star which resulted in bloated stars ( not a good night for me )
How did find seeing up there on the Ridge ?
Martin

Anth10 (Anthony M) · #9 06-04-2022, 08:32 PM

Peter,
As an impartial observer I have to agree with the majority in regards to the slightly out of shape stars however my interest lies in the center of this image- a stunning view of the intricacies of the core, very impressive.
Regards,
Anthony

willik (Willik) · #10 07-04-2022, 01:04 AM

IT looks ok not your standard Peter but you can always try a again

Nikolas (Nik) · #11 07-04-2022, 09:24 AM

Only out of shape stars and they are so minute appear to me in the right top corner, maybe a little tilt still in the image train? As for the mage itself it's spectacular and a little crop of the corners of the image will eliminate the so called "egginess."

Mickoid (Michael) · #12 07-04-2022, 10:17 AM

Great detail in the core Peter, eggy stars or not, it's a great start and adding RGB data will probably help disguise any imperfections to their shape. Looking forward to seeing the final result.

Peter Ward · #13 07-04-2022, 10:54 AM

Thanks one and all for your comments..which I'll take on board.

Problem with tight, long FL images is they show even the slightest glitch.

I also have to fess up....as I am likely the cause of this recent deluge

A nice man from UPS delivered a care package from Astro-Physics yesterday (image attached) optimized for my AP155.

Very keen to try this puppy out with the QHY

multiweb (Marc) · #14 07-04-2022, 01:32 PM

Quote:

Originally Posted by Peter Ward

Thanks one and all for your comments..which I'll take on board.

Problem with tight, long FL images is they show even the slightest glitch.

I also have to fess up....as I am likely the cause of this recent deluge

A nice man from UPS delivered a care package from Astro-Physics yesterday (image attached) optimized for my AP155.

Very keen to try this puppy out with the QHY

Noice!... these are out of stock. Did you have to wait long?

Peter Ward · #15 07-04-2022, 03:16 PM

Quote:

Originally Posted by multiweb

Noice!... these are out of stock. Did you have to wait long?

Actually no. Ordered it about 2 months ago.

LKD (Luke) · #16 07-04-2022, 04:04 PM

Great detail in the galaxy. I can see on brief scrutineering 4 background galaxies? 1 question USB traffic settings can that influence read noise. Starting to realise how much I dont know!

gregbradley · #17 07-04-2022, 04:42 PM

Quote:

Originally Posted by Peter Ward

Actually no. Ordered it about 2 months ago.

Are you putting it on the Mach 2 mount?

Greg.

Peter Ward · #18 07-04-2022, 04:46 PM

Quote:

Originally Posted by gregbradley

Are you putting it on the Mach 2 mount?

Greg.

I could but, no. I'll swap out the 130mm in the dome (PMEII)

That said I've set-up the Mach2/155 combo and it is quite tidy. Not used
in anger yet....no prizes for the reason

gregbradley · #19 08-04-2022, 06:12 AM

Quote:

Originally Posted by Peter Ward

Actually no. Ordered it about 2 months ago.

Quote:

Originally Posted by Peter Ward

I could but, no. I'll swap out the 130mm in the dome (PMEII)

That said I've set-up the Mach2/155 combo and it is quite tidy. Not used
in anger yet....no prizes for the reason

Its nice to have choices.

Greg.

AdamJL · #20 08-04-2022, 03:17 PM

Quote:

Originally Posted by Peter Ward

Thanks one and all for your comments..which I'll take on board.

Problem with tight, long FL images is they show even the slightest glitch.

I also have to fess up....as I am likely the cause of this recent deluge

A nice man from UPS delivered a care package from Astro-Physics yesterday (image attached) optimized for my AP155.

Very keen to try this puppy out with the QHY

Sort of related to your recent posts, Peter, I noticed on your site you're a "Factory Authorized Australian Agents" for AP.

Long term plans for now, but tossing up between a Mach2 and a 10u GM1000. Do you import AP mounts to Aus? I don't see a storefront etc on your site.