M57 - First Attempt, at last

[SnakeyJ]

Might not be much to look at but after many attempts I finally got a full set of data for this - processing can wait until tomorrow, but looks ok.

Red channel only so far - DSS and quick levels in Gimp2:

Over exposed and some fixed pattern noise/banding coming through which I haven't had before with the QHY5L-II (other than in preview after changing gain), but surprised how much detail for 20 x 20s subs.

Hopefully I can get something reasonable from the full set tomorrow.

[Daddystu]

Good shot. I cant get my images to load in gimp for some reason. I keep getting the tiff error whether I augment them in DSS or not.

[SnakeyJ]

Good shot. I cant get my images to load in gimp for some reason. I keep getting the tiff error whether I augment them in DSS or not.

Cheers - should get some proper processing time on it today!

Re the Gimp problems:

Possible that DSS is saving TIFFs with some extended information or something that Gimp doesn't like. I normally work with FITS format for these 16bit images, from capture - process within DSS and output as either FITS or PNG, though I'm pretty sure I have used TIFF before for source and output format.

Just done a test one now - output from DSS as TIFF Image (16 bit/ch), no compression and apply adjustments to the saved image options ticked.

Opens fine in Gimp with the usual warning that Gimp will process as 8bit rather than 16 - otherwise fine.

I'm using Gimp 2.8.6 on Win 7 x64.

If you still get the issues post one of the output files over and I shall have a look.

[SnakeyJ]

Ok the star colour is off, and I had to heavilly stretch/clip the data to try and get rid of some FPN/vertical streaking. That aside I'm quite impressed with the resolution and amount of detail and very pleased to finally get a result on this subject, though if I can iron out the camera issues I will come back on this at longer focal length and try and get some better data.

[Jannis]

That's a quite nice capture there.

You took this with the QHY5L-II, btw?

[SnakeyJ]

That's a quite nice capture there.

You took this with the QHY5L-II, btw?

thanks Jannis.

Yes QHY5L-II mono, full frame 1280x960 @ 12 bit, at F4.5 prime focus with my SW Exp200P and SW CC/0.9xFR, using the Baader CCD LRGB filters. I've processed with darks but no flats.

It's very sensitive, but noisy especially with ambient temp around 18C last night, but should have this actively cooled in the not too distant which should really clean up the signal and remove 90% of the noise..

[lensman57]

Ok the star colour is off, and I had to heavilly stretch/clip the data to try and get rid of some FPN/vertical streaking. That aside I'm quite impressed with the resolution and amount of detail and very pleased to finally get a result on this subject, though if I can iron out the camera issues I will come back on this at longer focal length and try and get some better data.

That is a pretty good result for such a short exposure, considering that most of us image at F6~F7 you are about 1-1/3 stops faster, even so I think that your sky must be pretty dark. Impressive capture.

A.G

[Jannis]

thanks Jannis.

Yes QHY5L-II mono, full frame 1280x960 @ 12 bit, at F4.5 prime focus with my SW Exp200P and SW CC/0.9xFR, using the Baader CCD LRGB filters. I've processed with darks but no flats.

It's very sensitive, but noisy especially with ambient temp around 18C last night, but should have this actively cooled in the not too distant which should really clean up the signal and remove 90% of the noise..

Impressive! .I'm about to order this cam too, will be interesting to see how it will perform in the -15c wintertime then.

I can't aford any LRGB filters though, so i guess i'll have to wait maybe untill next season before i can use it for anything else but a guide-cam.

[SnakeyJ]

Impressive! .I'm about to order this cam too, will be interesting to see how it will perform in the -15c wintertime then.

I can't aford any LRGB filters though, so i guess i'll have to wait maybe untill next season before i can use it for anything else but a guide-cam.

Wintertime will be great, especially in LX mode where you are not generating much heat. The design is quite good for heat dissipation, taking the heat out via a cold finger and bulkhead to the case, but at high frame rates it builds a fair amount of heat. There are some driver issues in LX mode, though this is also the case with the other MT9M034 based ZWO ASI 120MM. Both are very popular new cameras and the developers seem to be comitted to ironing out the bugs.

Re the filters - keep an eye out on the classifieds and ABS, you'll see the 1.25" astronomik and baader LRGB sets come up quite regularly as people sell on to fund 2" filter sets for the newer bigger sensors.

Best of luck and look forward to seeing some images.

[Superdavo]

Nice!

[SnakeyJ]

That is a pretty good result for such a short exposure, considering that most of us image at F6~F7 you are about 1-1/3 stops faster, even so I think that your sky must be pretty dark. Impressive capture.

The skies pretty good, but certainly not best conditions last night with a fair bit of thin high cloud and full moon - I was just past Zenith pointing NW away from the moon, but the transparancy was good and the seeing was pretty reasonable looking straight up. Mainly I think its the high QE of this CMOS, but resolution looks pretty good and its nice to get the Mag 15s in the centre of the nebula.

I'm really looking forward to having a go with some active cooling and longer guided subs, though the small diagonal limits this for small objects. For the extra cost the Atik Titans and Brightstar Mammut's (or even the QHY6) are really the way to go for small DSOs as they have the cooling, decent sony CCDs and 16 bit ADCs, though the QHY5L-IIM creams both of these for high speed planetary and solar.

[VigdisVZ]

Long time no see Jake! Good to see you're banging out some great pictures. Can't wait for the dark season to return up here in the north!

[Gonzo]

I have the same camera, amazing what you can achieve with that tiny camera. Well done.

[Gonzo]

Forgot to mention that I'm surprised not to see too much noise for 20sec exposure.

I've tried it the other might when it was free from clouds... below is showing '53 Cas' and it was a 2.5 or 3 seconds exposure, single shot.

When I was pushing it to 10sec+, I was getting some noise. Mind you, I haven't had much time with the camera since I bought it, so I'm not yet familiar with the right settings.

(I used a 200mm f3.5 Hoya lens + that QHY5ii-L on eq1)

[SnakeyJ]

Long time no see Jake! Good to see you're banging out some great pictures. Can't wait for the dark season to return up here in the north!

Cheers Carl - only experimenting with all this at the moment, though determined to get some data (even dirty/noisy) and learn some of the tricks before forking out serious money on a proper CCD setup. I think I'm a bit luckier than you and most of UK at 51deg N, it's getting pretty dark here now after 11:30hrs and if the weather allows I'm out setup and doing my polar alignment around 22:20hrs. Though don't think I'll every get the same quality of dark sky that you enjoy over the winter. August tomorrow so the nights should be drawing in and the skies darkening very soon.

I got some nicer data on M27 on Monday night, different thread over in DSO Imaging - but if I can get my own colour data on this tomorrow I'll be very happy.

Jake

[SnakeyJ]

Forgot to mention that I'm surprised not to see too much noise for 20sec exposure.

I've tried it the other might when it was free from clouds... below is showing '53 Cas' and it was a 2.5 or 3 seconds exposure, single shot.

When I was pushing it to 10sec+, I was getting some noise. Mind you, I haven't had much time with the camera since I bought it, so I'm not yet familiar with the right settings.

(I used a 200mm f3.5 Hoya lens + that QHY5ii-L on eq1)

Cheers Gonzo,

Looking pretty good to me with that, though I think with these cameras (which are sensitive/fast, but noisy), you need to grab as many subs as possible and stack these (with dark frames). I'm still only playing/learning, but I can capture 45 x 20 sec subs in 15 minutes @ 15-20% gain - I'm probably only picking 50-60% of these (due to wind and cloud), but a stack of 25 seems to work quite well with Deepsky stacker. I've just got myself a guidescope/webcam, so hope to be experimenting with PHD, lower gain/longer exposures - but with my 200P and HEQ5 combo this will only be viable in very light breezes! When I do graduate to CCD or DSLR the QHY should still be providing very good service for as a guide and planetary cam.

I've got some other threads over in DSO Imaging on M13, M92, M3 - though think my best results so far is on M27. Getting there slowly and lots to learn, but definitely pleased with some of the progress.

[NickK]

There's more detail in there.. a bit of deconv on my favourite target

[SnakeyJ]

Cheers Nick - great tip and a load more detail exposed. It certainly is a beautiful object (viewed from a safe distance). I'll have to investigate the deconvolution options in Gimp to see if I can work out the controls and pull this out, guessing it will behaviour similarly to the Wavelets tool in Registax. So far I've tried to avoid the sharpening tools for fear of adding more noise to the images and concentrated instead on the curves, alignment and colour tools. I will definitely revisit M57 soon, probably with a barlow at longer focal lengths and exposures once I get the PHD guiding working nicely. Thanks for the tip. Are those tiny pinpricks of light around the central dwarf star knots of dust, or feinter background stars in this (my glasses need a good clean)?

Jake

[SnakeyJ]

There's more detail in there.. a bit of deconv on my favourite target

Just had a closer look at that in Gimp and the detail and difference over my original process is stunning - very much appreciated Nick, I'll have a play with this function in Gimp to see if I can master some of these darker arts!

[NickK]

A bit of self promoting of two threads that may be of interest:

Firstly a bit about "Point Spread Function" (PSF):

Next up, what I did to your image:

If you can find a PSF deconvolution function then that should help - wavelets are one form, but are a bit heavy handed.

[SnakeyJ]

Nick,

Many thanks - looks quite a steep learning curve for me, but those are extremely useful and comprehensive guides. Hopefully this will get me off on the right track.

I'm just grabbing some data on M27 again in beautiful conditions so hopefully can experiment with this after my first process - seems like capturing the data is the easiest part at the moment, but hopefully I'll get a little quicker on the processing in good time.

Jake

[Russe]

There's more detail in there.. a bit of deconv on my favourite target

Right! I never tried to deconvolute! Whenabouts are you doing this in your processing routine?

[NickK]

Right! I never tried to deconvolute! Whenabouts are you doing this in your processing routine?

The easiest form - remove the CCD noise (darks), then apply flats, you can then stack and then apply.

The more accurate/complex form is darks, flats and then apply with each sub, then stack.

Also you can up-size before alignment, align, stack, deconv and you may recover additional details too.

You asked about the structures appearing in the ring - Hubbles photo does these justice:

http://upload.wikimedia.org/wikipedia/commons/0/0d/Hubble_reveals_the_Ring_Nebula’s_true_shape.jpg

[SnakeyJ]

You asked about the structures appearing in the ring - Hubbles photo does these justice:

http://upload.wikime..._true_shape.jpg

I hadn't seen that HST image before - but that is truly awesome!