M33

[CCD Imager]

Around 8 hours worth of data from Ollys pad.

I took my Skywatcher Esprit 150mm, mounted on a 10 micron GM2000 and QSI 683 camera. All images unguided 10 minute subs.

[michael.h.f.wilkinson]

Very nice indeed

[gnomus]

Nice image.  Not 'overdone'.  Congratulations.

[Nova2000]

Nice image. That mount seems to track quite well. Great image. 

[Adriano]

Unguided ten-minute subs?! Wow! Amazing image of M33!

[simmo39]

V nice!

[DaveS]

Not overdone at all, the hot blue stars are there but not overpowering and the HII regions are showing up nicely.

Not truly "unguided" as the 10-micron mounts guide on their encoders, as do ASA.

[CCD Imager]

Dave

May be pedantic, but no guider was used at all, the mount tracked at high resolution due to the encoders having virtually zero PE

 

[DaveS]

These encoder mounts rely on an accurate sky model so the mount can correct between where it should be and where it actually is. This will vary depending on where it is pointing, hence the large number of points. ASA mounts go further and make a new local model for each imaging run in addition to the overall model. I regulaly see my ASA DDM60 get errors down to 0.1 - 0.2 arcsec. The high resolution encoders (0.03" for my DDM60) mean that wind gusts can be corrected almost instantly.

[ollypenrice]

Well it's a very nice result. We talked quite a lot (in a banterish kind of way!!) about processing and CCD Imager's result is true to the processing principles he believes in and which I admire. Nice high black point, no intrusive sharpening or noise reduction, the colour allowed to speak for itself. This is gently done and leaves you feeling that the data maybe has a tiny bit more to give. This is so much better than the feeling that it has had its neck wrung! This looks like M33, not Las Vegas. 

Olly

[CCD Imager]

Dave

No need to teach me about absolute encoders, I am full convert, couldn't live without them now!

The ASA and Astrophysics mounts have Renishaw encoders that are of higher resolution than 10 micron, but as you see from my image, tracking is perfect. I believe there are bigger errors elsewhere than contribute to tracking issues, (sloppy optics, focusers etc). I performed a 60 point model that included compensation for temperature, humidity and atmospheric pressure. Not sure I would want to do a new model for each image, wastes valuable imaging time

[DaveS]

Sorry, not really trying to teach you about encoders. The MLPT that ASA mounts do only takes about 5-6 min,  all it does is track through your imaging path taking photos (As many as you specify) and solve them on the fly. It then knows the specific corrections to make. I regularly see it get 1.5 ' over 2 hours down to 0.1".

You might gather I'm a bit in love with my DDM 60 .

[CCD Imager]

Dave

 

Ditto re the 10 micron! I'm pleased to see a happy ASA owner as there were some issues when they first started.

[swag72]

Great data shining through that's for sure 

[PatrickGilliland]

Tidy well process and subtle - nice work.

Paddy