M33 Triangulum

[ApophisAstros]

Took this over Saturday and Sunday at Cairds DSC.

Constellation   Triangulum
Right ascension   01h 33m 50.02s[1]
Declination   +30° 39′ 36.7″[1]
Redshift   -0.000607 ± 0.000010[1]
Helio radial velocity   -179 ± 3 km/s[2]
Galactocentric velocity   -44 ± 6 km/s[2]
Distance   2.38 to 3.07 Mly (730 to 940 kpc)[3][4]
Apparent magnitude (V)   5.72[1]
Characteristics
Type   SA(s)cd[2]
Mass   5 × 1010[5] M☉
Number of stars   40 billion (4×1010)[6]
Size   ~60,000 ly (diameter)[6]
Apparent size (V)   70.8 × 41.7 moa[1]

40 x Lights
22 x Flats
Imaging telescope or lens:SkyWatcher 120ED Imaging System for Canon DSLR Cameras
Imaging camera:Canon 1000D modified
Mount:Skywatcher EQ6-R PRO Synscan
Guiding cameras:Skywatcher 9x50 Finderscope,  QHYCCD 5L-II MONO
Focal reducer:Skywatcher 0.85x Focal Reducer/Corrector for Evostar-120ED
Software:ADOBE PHOTOSHOP CC,  DeepSkyStacker x64 by Luc Coiffier, Tony Cook, David C. Partridge Deepsky Stacker 4.1 64bit,  Astro Photography Tool
Accessory:QHYCCD PoleMaster
Roger

[Carole]

Much better colour than the versions you have been E Mailing me.

Carole

[MarkS]

An excellent result and very nicely processed.  You should be very proud of that image.

Mark

[ApophisAstros]

Thanks Mark , maybe my DSLR swan song as hoping to step up to CCD Mono imaging soon.
Roger

[MarkS]

Thanks Mark , maybe my DSLR swan song as hoping to step up to CCD Mono imaging soon.

Are you planning to do some narrowband imaging?  Otherwise I can't see much point in mono sensors. However I will admit that my opinion on this is somewhat controversial - the debate on LRGB vs RGB imaging is certainly an interesting one 

Mark

[Carole]

You can get much more detail out of a mono camera Mark, that is unless we have your expensive kit and skills.  It's also easier to use, though the processing is somewhat challenging at times.

I could not get the detail that I do with a modified DSLR.

Carole

[MarkS]

You can get much more detail out of a mono camera Mark, that is unless we have your expensive kit and skills.  It's also easier to use, though the processing is somewhat challenging at times.

I could not get the detail that I do with a modified DSLR.

You think a mono camera with the attendant complexities of a filter wheel is easier to use than a one-shot-colour?

Fair enough that you say my kit is expensive but it's cheaper than an Tak FSQ refractor with cooled Atik 11000 mono camera plus filter wheel and filters.  So let's do a comparison.

Take a look at this fantastic image of Tom Donahue's (a collaborator of Ollie Penrice) taken over 25 nights in Spain and using 60 hours (yes 60 hours!) of data taken with the above mentioned equipment:
https://www.space.com/17553-night-sky-photo-nebula.html
Let's be charitable and call it 30 hours of data because he says his first 30 hours of data was of low quality.

Now compare it with mine taken in France last year (lower in the sky) which uses just 80minutes (yes just over 1 hour) of data and an uncooled DSLR:
http://www.markshelley.co.uk/Astronomy/2017/antares.html

Agreed my image has a bit less H-alpha but for a given level of expenditure would you prefer to use 25 nights to take a single image or 2 nights?

Technology moves on ...

Mark

P.S. In Spain I would have captured that data in a single night

[Carole]

I am comparing same scopes with standard DSLR V Mono CCD same sky conditions  Mark, not different people's data, equipment, sky conditions and skills. 

All I know is I can get far better images with a mono camera than a coloured camera, be it OSC or DSLR.  when I first got a Mono camera, I did same targets on 2 different nights - one night with the DSLR and the next night with the Mono camera for comparison, and was blown away by the difference in the two. 

I would NEVER go back to DSLR DS imaging after using a mono camera with the odd exception for example if I was on holiday and had to take the skytracker instead of the full regalia.

Yes the capture and processing is far more complex I agree with that.  It did take me quite a while to get to grips with it all, but I enjoy the processing anyway. 

Your A7S is a magical camera, and probably matches many Cooled CCD cameras, coupled with your Tak Epsilon and your incredibly good skills is combined a killer combination.

But the downside is it doesn't do narrowband and some data I suspect is not visible to it, though would love to be proved wrong. 

But we are talking here of comparing your bog standard Modified DSLR that Roger has to a cooled CCD camera.

By the way, Roger has just rung me.  He has bought a ZWO ASI mono camera which will mean short subs for him as it has a CMOS chip.  This CMOS technology has come on the market after I had bought my Mono cameras. 

Carole

[MarkS]

By the way, Roger has just rung me.  He has bought a ZWO ASI mono camera which will mean short subs for him as it has a CMOS chip. 

Carole

Well done Roger!  It will be very interesting to see M33 taken with the new camera, if you care to do so.  You should notice a really big difference compared with your "bog standard Modified DSLR".

For the avoidance of doubt, I am being absolutely serious when I say that.

Mark

[ApophisAstros]

I appreciate all advice and input from senior imagers whatever it may be, i have a long way to go before i can dispute or agree what any ones comments are, take them all on board at the moment.
Rodge

[Carole]

Actually as Mark has suggested, M33 with the mono camera would be a good comparison, though the processing might be a challenge as it's not the easiest I have processed.  Also The Crescent but that would be better in narrowband and might have to wait until you have afforded the NB filters.

So yes, repeating images you have already done for comparison is a really good idea.

Carole

[The Thing]

I thought I'd just put in my oar and stir it around a bit...

My 'new' camera, the ZWO ASI294 MC Pro, is an OSC CMOS camera and now I seem to have mastered collimating my TS1506UNC  Newtonian I am getting some amazing detail (referring to Carole's post). What's stumping me is the post-processing otherwise you would be seeing a slew on new images from me. The camera just captures so many faint details the background stars overwhelm everything. I've just bought "Inside Pixinsight" to fix this lack of knowledge so hopefully soon there will be some piccies. Meanwhile I have done 5 hours on the Western Veil and can see detail I can't find in any images I can find on the web (not looked at Hubble versions!), I just need to kill them damn stars.

The camera has a huge well depth and very little noise of any sort when cooled to -20c, so subs are clean and stars not saturated with a 300s exposure at f4. It also can do full frame  4144x2822px at 16fps and planets at 150fps with 6ms exposures without any bother, so hugely versatile.

I am very glad I moved to this OSC solution after DSLR as mono seems a huge phaff. HOwever in light polluted skies I can see it has big advantages. One feature on my camera is it can do mono binning (and colour 2x binning) so potentially opening teh way for using some filters.

HTH

Duncan

BTW very nice Triangulam!

[ApophisAstros]

yep!
Roger

[MarkS]

I am very glad I moved to this OSC solution after DSLR as mono seems a huge phaff. HOwever in light polluted skies I can see it has big advantages. One feature on my camera is it can do mono binning (and colour 2x binning) so potentially opening teh way for using some filters.

It's similar to the point I was making.  The Sony A7S is as good as (or better) than any OSC (one-shot-colour) astro-camera except it doesn't have cooling.  Current OSC cameras are using older sensors than the A7S.  Although the A7S doesn't have cooling, it also doesn't suffer the same sensor self-heating during long exposure imaging that afflicts every single Canon DSLR (Nikon cameras are also very good in this respect - I'm tempted to get myself a Nikon D5300 as a back up camera - I'm just waiting for some sensor self-heating data that I've been promised).  As for RGB vs LRGB imaging, Juan, the developer of PixInsight, strongly argues for RGB imaging instead of LRGB because of the compromises introduced by processing LRGB.  The main problem is that the L channel typically picks up much fainter structures than the RGB channels that are added over the top which creates an imbalance in the processing.  As far as I can see, LRGB was a good solution in the days of high read noise CCD imaging but those days are almost behind us now (thankfully).

However, to do effective imaging with RGB or OSC requires good dark skies.  For more light polluted skies I would certainly recommend mono imaging because it is more versatile - it allows both narrowband and RGB imaging.  Also, given similar sensors, imaging with a mono camera is never worse than with a OSC, so a mono camera is never a bad choice.

Mark

[Carole]

L channel typically picks up much fainter structures than the RGB channels that are added over the top

This is exactly my point, I don't find it a problem combining it with the less detailed RGB, 
BTW the luminance is added over the top of the RGB (not RGB added over the top of the luminance).
When I stack the RGB together, it doesn't contain anything like the detail that the luminance channel contains.
Maybe at some point I will post up separate Luminance and RGB images and let you see the difference.

I do agree that processing is far more complex with mono imaging and requires a fair amount of practice and learning of a few new processes.

Carole