July Deep Sky Imaging Challenge - Images

[DavidTrap]

Thanks to all those who contributed to the June thread! Some fabulous images have been posted allowing great comparisons between techniques and equipment. I hope everyone has learnt from the experience. Let's hope there will be some more comments during this month's challenge.

Targets for July:
NGC 6334 - Cat's Paw Nebula
NGC 6744 - Spiral Galaxy in Pavo

Many seasoned imagers will have imaged these targets before, possibly even this year - it would be an exercise in frustration to attempt to find something that had never been done. The challenge may be to image these objects with new equipment or try some new processing techniques.

The challenge is open to all comers. There are no classes or categories – everyone may post images for both objects. Seasoned imagers will hopefully provide some inspiring images, along with advice for beginners with more modest equipment.

Please submit all images with the following standard information:
* Scope: (+/- reducers/flatteners)
* Imaging device:
* Mount:
* Guiding:
* Exposure details: (include ISO for DSLRs, temp for CCDs)
* Stacking method: (Median, average, sigma, etc. Darks, flats &/or bias frames)
* Summary of post processing:
* Darkness of imaging site: (Good, bad, ugly!)
* Date(s) image taken: (Ideally the image will be taken during this month, but previous work is not excluded to allow for weather and other life commitments)

There will be two threads – this one for posting images and another to post comments.

The usual 200kb limit for files applies. Adding a link to a higher resolution file is encouraged.

There will be no voting on the best image(s) of the month. The aims of the game are participation, especially from beginners, and learning, hence the standard list of information requested. The “methodology” of this challenge is open to review, and comments are appreciated – please PM me.

Cheers,
DavidTrap

[peter_4059]

OK I'll kick off this month....

* Scope: GSO 10" f5 Newt with Universal Paracorr
* Imaging device: QHY8 pro
* Mount: EQ6 with EQMOD
* Guiding: PHD with SBS mounted 80mm guidescope/DSI II pro guide camera
* Exposure details: 35x5mins at -5 degC
* Stacking method: DSS auto adaptive weighted average with flats and bias frames (20 of each)
* Summary of post processing: PS CS3
* Darkness of imaging site: (Good, bad, ugly!) Ugly
* Date(s) image taken: 19th June 2010

[DavidTrap]

With the weather next weekend looking questionable, I thought I'd better get out last night to ensure I had an offering this month. Not from my favourite dark site, but in the backyard 5km from the Brisbane CBD.

* Scope: Takahashi FS-102 with F6 reducer
* Imaging device: modded 350D
* Mount: AP Mach1GTO
* Guiding: PHD, SSAG, WO 70mm ZenithStar
* Exposure details: 15 x 300sec exposures at ISO400, ambient temp ~7-8 degrees
* Stacking method: 20 darks & flats subtracted, sigma clip stack
* Summary of post processing: Levels, Curves, Shaddows/Highlights, Saturated, Sharpened and noise reduction with NoiseWare
* Darkness of imaging site: Ugly!
* Date(s) image taken: 03.07.10

Link (http://users.tpg.com.au/dctrap/astrophotos/NGC6334DT.jpg) to larger version 1.4Mb

[Bolts_Tweed]

No cats round here but you can see where they've been - the rats eat them all. I am so tempted to get into my library of cat jokes but that would just be to un'pc.

Had a play last night but only got Ha data before the sky went west - so I had a little play today with just the Ha data. Synthesized a blue channel then synthesized a green and consequently the stars were rubbish so I took em out. I got this which might be worth a laugh. As you say David the weather next week looks questionable but if it is any good i'll put some real colour behind it and maybe even leave the stars in.

* Scope: Televue np 101is
* Imaging device: SBIG ST8300 with Astronomik 6 nm Ha
* Mount: EQ6
* Guiding: PHD, QHY5 Orion short tube 80
* Exposure details: HDR blend of 1.5, 2.5, 5, 7.5 and 10 min subs (10 of each)
* Stacking method: no darks & flats subtracted, median stack in Maxim 80% normailisation
* Summary of post processing: As discussed above - done in Pixinsight but channel synthesization in CS2
* Darkness of imaging site: Pretty dark (Leyburn)
* Date(s) image taken: 05.07.10

Mark Bolton

[joecool]

Had to post this lot before I played with it some more over the weekend. It surprised me to see the galaxy after stacking when a 5min exposure shows nothing at all. And no bright stars nearby to find it either without relying on the telescope mount to put the scope on target. Got some odd out-of round stars here... I'm happy to blame it on poor seeing. But maybe because I forgot to collimate the scope???

* Scope: Meade LX200 10"
* Imaging device: Canon EOS 450D
* Mount: Super wedge on tripod
* Guiding: Celestron Omni XLT 127 (5" SCT) with Orion Starshoot Autoguider and Meade f3.3 reducer.
* Exposure details: 9x5min light, then the clouds rolled in. And the first lot of 10 failed to download to the laptop. Problem with MaximDL...
* Stacking method: Sigma clip with 10x5min dark and 10x0min bias
* Summary of post processing:
Removed pedestal. Applied curves 3 times as a convex curve ( higher on the left and flat at the top right).
Kernel filtered with Gausian blur 1.5 pixels radius. (Removes grain in nebulas/galaxies spiral arms.
Saved as jpg 100% quality with manual stretch set to linear and using planet screen stretch and auto-stretch enabled. Planet stretch setting removes excess haze around the outlier fainter arms of the galaxy. Re-sized to 1024 in Photoshop for this post.
* Darkness of imaging site: Looking south from a northern suburb site in Adelaide. Cannot see the 5th star of the southern cross with naked eye. Lots of clouds about.
* Date(s) image taken: 8/7/2010.

[bert]

Looks like no more imaging for this month. Clouds grrrrr..... So here is what I got for the one night that I did manage to get an image.

* Scope: Vixen ed103s, no reducer.
* Imaging device: Sbig st4000xcm
* Mount: eq6
* Guiding: AO8
* Focus: Focusmax and fli df2
* Exposure details: 42x 10 min subs
* Stacking method: Maxim dl median, darks applied, no flats.
* Summary of post processing: Levels, Curves, Colour boost. Noise ninja is what I am loving this month. Impatience is this months theme. Hate of the month: jpeg compression, closely followed by clouds.
* Darkness of imaging site: Sodium city
* Date image taken: 04.07.10

Brett Soames

[Bolts_Tweed]

This is the same Ha data with a bit more adjustment to the HDR (described in previous post) and R, G, B from the weekend

Data blended as :
Lum Ha + R (Lighten) -then Lum applied at 40%
Red (20 x 3 min) + 30% Ha
Green and Blue 20 x 3 min

I was worried about the colour gradient between the lower left and upper right but examination of the longer Ha images shows this whole region (below a top left to lower right diagonal) to be faint Ha causing the red cast. Decided not to process it out - looked too clipped if I did.

* Scope: Televue np 101is
* Imaging device: SBIG ST8300 with Astronomik 6 nm Ha and Astrodon E Series RGB
* Mount: EQ6
* Guiding: PHD, QHY5 Orion short tube 80
* Exposure details: Ha is a HDR blend of 1.5, 2.5, 5, 7.5 and 10 min subs (10 of each) - RGB 20 x 3 min subs on each blended as above
* Stacking method: no flats subtracted, SBIG Series dark on each exposure run (I refocus after 6 so a series dark every 20+ minutes or so)median stack in Maxim 80% normailisation
* Summary of post processing: Colour combined and blended in CS3, DBE, ACDNR , Histogram Stretching and Colour Calibration in Pixinsight - final tweaking in CS3 (Saturation mainly)
Darkness of imaging site: Pretty dark between the clouds (Leyburn) & Brass Monkey Cold (Camera at -25 degrees)
* Date(s) image taken: 05.07.10 Ha and 09.07.10 RGB

Can someone confirm - i've just calibrated a new monitor at home and when I look at this image on the work computerit is all washed out - far too bright - does it look too bright to anyone else? If so my calibration by Adobe Gamma is obviously wrong - the original process was probably just slightly clipped - PM would be ok if necessary

Mark Bolton

[telemarker]

Lots of red cat's paws. Just for a little contrast I'll submit a narrowband rendition using the Hubble palette. It's very green.


* Scope: NG ED127
* Imaging device: SBIG ST-8300 with Baader 1.25" Ha, OIII and SII filters
* Mount: HEQ5pro with EQMOD
* Guiding: PHD 8x50 Finder-guidescope with a DSI I pro guide camera
* Exposure details: 8x15mins at -15 deg for each filter auto dark subtraction
* Stacking method: DSS median with flats, each colour registered
* Summary of post processing: PS combine, stretch, balance, Ha as Lum
* Darkness of imaging site: My backyard
* Dates image taken: 3rd and 4th July 2010

[Moon]

This month I was trying out a new scope - it's still a work in progress. I was making modifications to reduce the vignetting and re-collimating between subs so it was a bit difficult to put it all together into a final image - especially the flats.

* NGC 6334 - Cat's Paw Nebula
* Scope: AT8IN + Paracorr STL
* Imaging device: STL-11000M
* Mount: Paramount ME
* Guiding: Self guide + MaximDL ~ 12 sec exposures. Half way through I reverted from Directguide to guider relays.
* Exposure details: HaLRGB 100:120:110:70:90 (8:10 total) @-20C
* Stacking method: Median combine in CCDStack using the CCDIS plugin, Darks + flats
* Summary of post processing: CCDStack (Calibrate, align, Normalise, stack, DDP) then PS CS5 for a bit of saturation and jpg conversion.
* Darkness of imaging site: Suburban backyard
* Date(s) image taken: 5/6/11 July 2010

James

[RobF]

This represents 95mins worth of 5min shots with the QHY9 from the South Pacific Star Party. It was late (and cold!) on the 2nd night, and I was getting a bit tired and lax with my tracking/balance which has smeared the stars a bit and made it hard to get any more detail in the galaxy. Great object and glad I had a go.

* Scope: Skywatcher 8" Newt with Baader MPCC
* Imaging device: QHY9 with QHY LRGB filters
* Mount: HEQ5Pro
* Guiding: Orion SSAG, 9x50 finderscope, Maxim, 1.3sec exposures
* Exposure details: LRGB 35:20:20:20, -25 degrees
* Stacking method: PixInsight, bias/darks/flats, separate LRGB stacking, deconv on L only
* Summary of post processing: Pixinsight deconv, stretches, curves, colour cal, noise, resized to jpg
* Darkness of imaging site: Excellent
* Date(s) image taken: 1:46 to 4am 15/5/10 :whistle:

[jjjnettie]

1 hr and 38 minutes of data ( a mix of 5min and 2min subs, 43 frames total)
Darks and flats taken.
Canon 20d @ iso1600
Taken from my reasonably dark back yard.
ED80
HEQ5Pro
Guided using qhy5 and PHD
Stacked in DSS and Processed in CS3.

[Shiraz]

* Scope: GSO 8in f4 with MPCC and moonlite focuser
* Imaging device: QHY8
* Mount: HEQ5 pro on jarrah post
* Guiding: 50mm modified finderscope with QHY5(colour) - PhD through AT4.
* Exposure details: ~110 min total, mix of 5 and 3.3 min subs at whatever temp the QHY8 got to.
* Stacking method: stacked in Nebulosity with translation and rotation compensation. No flats or darks to minimise noise, but used bad pixel removal.
* Summary of post processing: Nebulosity “curves” used to bring up low signal regions. IRIS to flatten background and sharpen image with substantial amount of RL deconvolution. GIMP2 to tidy up residual imperfections and prepare for posting as a JPEG. Heavily cropped and resampled to fit post requirements.
* Imaging site: Seeing below average but no wind. 1/3 moon for much of the session. Clouds terminated the imaging session not long after the moon set.
* Date(s) image taken: 17/7/2010
* Philosophy: Didn’t image for anywhere near long enough and need more signal to bring out the structure in the outer regions. Poor seeing meant significant deconvolution processing was required to extract any detail and tracking was also below par, resulting in saturated and distorted stars. However, it’s still a keeper because the beauty of the galaxy itself compensates to some degree for some of the technical defects. Will certainly be trying this one again.

[bert]

* Scope: Vixen ed103s, no reducer.795fl.
* Imaging device: Sbig st4000xcm
* Mount: eq6
* Guiding: AO8
* Focus: Focusmax and fli df2
* Exposure details: 20x 10 min subs used
* Stacking method: Maxim dl median, darks applied, no flats.
* Summary of post processing: Levels, Curves, Colour boost. Noise ninja. Gradient exteminator to try to rid the image of effects of the almost full moon.
* Darkness of imaging site: Sodium city, near full moon
* Date image taken: 22.07.10

Brett

[Martin Pugh]

Hello
I would like to submit my repro of NGC 6744 for this month's challenge.

http://www.martinpughastrophotography.id.a u/images/NGC6744LRGB.jpg

* Scope: 12.5" RC
* Imaging device: SBIG STL11000M
* Mount: Bisque PME
* Guiding: Self Guided using AO-L
* Exposure details: LRGB 9.5.5.5 Hours, plus a few more binned 2x2 lum only to capture the outer arms.
* Stacking method: Fully calibrated, RCC Combine.
* Summary of post processing: Image calibration, blend of the unbinned and binned luminance. RGB combine in CCDStack. LRGB combine in Maxim. Deconvolution on L frame, with selective HPF. Finished off in PS CS4 - levels, curves, colour enhancement, light pollution removal etc.
* Darkness of imaging site: Average - Yass, NSW.
* Date(s) image taken: This is a repro of data first taken in late 2008. That probably disqualifies this image!

thanks
Martin

[Shiraz]

* Scope: GSO 8in f4 with MPCC and moonlite focuser
* Imaging device: QHY8
* Mount: HEQ5 pro on jarrah post
* Guiding: 50mm modified finderscope with QHY5(colour) - PhD through AT4.
* Exposure details: 55 min total of 5min subs at whatever temp the QHY8 got to.
* Stacking method: stacked in Nebulosity with translation and rotation compensation, with darks.
* Summary of post processing: Nebulosity “curves” used to bring up low signal regions. Slight RL2 deconvolution in IRIS to tidy up stars. GIMP2 to tidy up residual imperfections and prepare for posting as a JPEG. Heavily cropped and resampled to fit post requirements.
* Imaging site: Seeing about average with slight wind. Dark but some very thin cloud or ice at high altitude.
* Date(s) image taken: 4/7/2010
* Philosophy: There is a lot of nebulosity around this object, but that has been deliberately suppressed to make the cats paw shape the dominant impression.

Thanks for looking - although it was bit hard to get up the courage to post my effort on this one after seeing Martin's excellent image of 6744.