Ptolemy's Cluster (M7) in Scorpius

Octane (Humayun) · #1 25-05-2010, 11:21 PM

All,

Not exactly the best image to call a swan song for my current setup (the ED127 is gone, as is my William Optics ZenithStar, and the modified Canon EOS 40D), however, I did use my 5D Mark II for this at ISO-1600. Each sub-exposure is void of noise. I love this camera.

This is the only useable data from three night's of imaging at Frank Bonneville's place up at Manar (thanks Frank!). The other two night's worth, including 5+ hours on Rho Ophiuchus through a 200mm lens was a disaster as Frank's 20Da was flexing on my ADM Manfrotto ballhead mount. I thought I'd tightened it up pretty good, but, obviously not.

This is a crop from towards the middle of the frame, as the ED127's focuser is, in no uncertain terms, useless when it comes to illuminating a full-frame 35mm sensor. Also, as the camera is quite heavy, it wasn't sitting square and there's a bit of elongation happening.

Anyway, enough excuses -- it was my final image with my current setup until the new gear arrives, and I thought I'd share.

Read and view here.

Critique and bash away.

H

gregbradley · #2 26-05-2010, 12:32 AM

Diamonds on golden sand. Wonderful colours, best I have seen of the golden stars of the galactic core area.

Greg.

telemarker (Keith) · #3 26-05-2010, 12:39 AM

H, so many stars! They give the image that wonderful honey coloured warmth to offset the sparkling diamond stars of the cluster. Wonderfully processed to bring all the warm colours, contrasting dark nebulae and blue stars to life. Top image.

I hope the scope has a few more left in it

Suzy · #4 26-05-2010, 12:58 AM

I don't know anything about astrophotography, I just see this picture as incredibly breathtaking! Wow!

Hope you don't mind- I have just set it as my desktop background for the week.

RB (Andrew) · #5 26-05-2010, 02:42 AM

What a beautiful scene, lovely work indeed !
Unbelievable amount of stars in there.

I'm also keen to try out the 5D MkII on some astro work, I setup recently using the 20Da, didn't think to try out the 5DII as well.

Well done H.

richardo (Rich) · #6 26-05-2010, 02:55 AM

Holy golden baubles Batman

I thought your last image was your swan song for this camera H

Still a beauty of an image though.

How's the new ccd coming along??
Certainly look forward to your up and coming images with it!

Rich

Tom Davis (Tom) · #7 26-05-2010, 04:52 AM

A pretty image of a pretty cluster. Great going H!

Tom

iceman (Mike) · #8 26-05-2010, 05:58 AM

Needs diffraction spikes but a lovely image nonetheless

Top work H.

multiweb (Marc) · #9 26-05-2010, 07:59 AM

Great shot H. Love the colors and very well resolved. Top shelf.

h0ughy (David) · #10 26-05-2010, 07:59 AM

pretty image H. nice colour, pearls on a beach, but i can see you have elongated stars in the corners. Fantastic image just the same. Maybe if you kept the scope a tad longer you could have used something like the Hotech field Flattener, I found it to be brilliant to get rid of that feature in my shots.

So your scopeless, and stuck with a canon5D - whats your next scope?

SkyViking (Rolf) · #11 26-05-2010, 09:51 AM

Wonderful image! Seeing these dense starfields is always mind-boggling considering that we cannot even get to the nearest star yet... Fascinating image, thanks

TrevorW · #12 26-05-2010, 12:34 PM

Great shot H colours are spot on, I'm amazed how many stars have been captured for relatively short exposures, only 1hr total, the 5d appears to be a great camera even at ISO1600

There is a free plug-in available for PS called "Star Rounder" which could help with any elongation

I don't agree that you need spikes especially for this wide field vista

I see you are one of a few using IRIS, tried myself once but seemed a bit complicated although I'm yet too see a comparison between say IRIS and DSS as to whether it is much an improvement.

rogerg (Roger) · #13 26-05-2010, 01:04 PM

Can you imagine flying in a space ship towards and then just through the stars of M7 and having nothing but a wall of gold stars from top to bottom of your window? Would be quite breathtaking.

Nice colours, shame about the illongation of stars, but the colours, FOV, etc make this quite a thought provoking image

alexch (Alex) · #14 26-05-2010, 02:10 PM

I am running out of superlatives - this is fantastic!

I reckon elongated stars in the corners make it look more three-dimensional and draw attention to the middle of the frame.

Cheers,
Alex

jase (Jason) · #15 27-05-2010, 01:23 PM

Solid work H. The open cluster punctuates the golden star cloud nicely - good processing. Well done.

Octane (Humayun) · #16 27-05-2010, 05:14 PM

Greg,

Sparkling diamonds, indeed. One of my favourite clusters in a rich part of the Milky Way. Thanks, mate.

Quote:

Originally Posted by gregbradley

Diamonds on golden sand. Wonderful colours, best I have seen of the golden stars of the galactic core area.

Greg.

Keith,

Oh, mate, with the ST-8300 stuck on the back of it, there's oodles of images left in it. If the focuser does give you any hassles, speak to Wayne Schroeder at Starlight Instruments and he'll sort you out.

Thank you, sir.

Quote:

Originally Posted by telemarker

H, so many stars! They give the image that wonderful honey coloured warmth to offset the sparkling diamond stars of the cluster. Wonderfully processed to bring all the warm colours, contrasting dark nebulae and blue stars to life. Top image.

I hope the scope has a few more left in it

Suzy,

I suppose that's the intended aim -- to give you something to think about. Me, mind? No way -- go right ahead! Thank you!

Quote:

Originally Posted by Suzy

I don't know anything about astrophotography, I just see this picture as incredibly breathtaking! Wow!

Hope you don't mind- I have just set it as my desktop background for the week.

Andrew,

Cheers! I think your Takahashi refractors will have focusers adequate enough to illuminate the 35mm frame. Where we used to stick to ISO-400 on the older systems, do not be afraid to use ISO-1600 as a basepoint on the 5D Mark II. I consider it to be the standard ISO for astroimaging on that camera. If I had a fast focal ratio system, I'd actually be going down to ISO-200 and doubling/trebling my exposure duration for maximum dynamic range and low noise.

About time you got one. I'm looking forward to the 1Ds Mark IV (if it ever comes to fruition).

Quote:

Originally Posted by RB

What a beautiful scene, lovely work indeed !
Unbelievable amount of stars in there.

I'm also keen to try out the 5D MkII on some astro work, I setup recently using the 20Da, didn't think to try out the 5DII as well.

Well done H.

Rich,

So did I! But, there was one more left in it.

The STL-11000M is waiting quietly in its box for its filter set (Peter Ward's waiting on SBIG who are waiting on Baader). Hopefully it won't be long now. They'll be mated to a new optical system soon, too.

Quote:

Originally Posted by richardo

Holy golden baubles Batman

I thought your last image was your swan song for this camera H

Still a beauty of an image though.

How's the new ccd coming along??
Certainly look forward to your up and coming images with it!

Rich

Thanks, all.

H

Octane (Humayun) · #17 27-05-2010, 05:21 PM

Tom,

Thanks! I look forward to re-doing this area with the STL and see how I can improve on it.

Quote:

Originally Posted by Tom Davis

A pretty image of a pretty cluster. Great going H!

Tom

Mike,

You're 100% right. This is one of those ones that does need diffraction spikes. This wasn't actually my intended object that night, and, therefore, I didn't bother with the cotton thread. Perhaps next time.

Quote:

Originally Posted by iceman

Needs diffraction spikes but a lovely image nonetheless

Top work H.

Marc,

This was one of those images where I used the Bahtinov Mask and focused on a blue star. The Bat Grabber software told me that I was in focus, but, I was getting really bad blue halos around the bright stars of the cluster. So, after the first sub-exposure, I dialed the focuser back just a fraction and I minimised the haloing. It's still there, but, not as evident as it was in the single exposure.

Quote:

Originally Posted by multiweb

Great shot H. Love the colors and very well resolved. Top shelf.

David,

Yeah, darn annoying corners on the full frame. And, darn focuser sag. And, darn non-orthogonality!

I was very close to buying the Hotech camera adapter system, and, would have also got the field flattener as well, but, alas.

The 5D Mark II is being used for my other stuff, it's the STL-11000M that's sitting quietly waiting to eat stars.

You'll soon see what my new scope will be. Suffices to say, I won't have to worry about corners anymore!

Quote:

Originally Posted by h0ughy

pretty image H. nice colour, pearls on a beach, but i can see you have elongated stars in the corners. Fantastic image just the same. Maybe if you kept the scope a tad longer you could have used something like the Hotech field Flattener, I found it to be brilliant to get rid of that feature in my shots.

So your scopeless, and stuck with a canon5D - whats your next scope?

Rolf,

Thanks, sir! Just makes you wonder how many of those billions of pin-pricks could potentially harbour sentient life? Thanks!

Quote:

Originally Posted by SkyViking

Wonderful image! Seeing these dense starfields is always mind-boggling considering that we cannot even get to the nearest star yet... Fascinating image, thanks

Thanks, all.

H

Octane (Humayun) · #18 27-05-2010, 05:28 PM

Trevor,

Thanks, mate. I have always found that for star clusters, such as these, you don't really need long exposures. Especially on a DSLR where you start saturating pixels really quickly. Remember, I'm shooting at ISO-1600. For equivalence, I would have been shooting 20-minute sub-exposures on the old 40D. As mentioned previously, that ISO-1600 is so clean on the 5D Mark II, that it is essentially the new ISO-400.

Thanks for the plug-in suggestion, but, I'm quite averse to using other people's plug-ins and enhancement tools. Part of the challenge in all this is to push my knowledge of Photoshop each time. There's stock standard tools that I use, such as levels, curves, saturation, channel mixing, masking, etc. I could easily dabble with the pinching and distortion tools to try and resolve any anomalies but it just wasn't worth it. After all, it's just one hour of exposure. :grin:

Once you get the hang of IRIS, it is marvelous. If my understanding is correct, there really isn't all that much difference between DeepSkyStacker and IRIS. Essentially, if what I'm lead to believe is true, DeepSkyStacker is basically a user-friendly implementation of IRIS. I'm not sure how comparable the star matching and transformation routines are, but, as far as stacking goes, it's probably six of one, and half-a-dozen of the other.

Cheers!

Quote:

Originally Posted by TrevorW

Great shot H colours are spot on, I'm amazed how many stars have been captured for relatively short exposures, only 1hr total, the 5d appears to be a great camera even at ISO1600

There is a free plug-in available for PS called "Star Rounder" which could help with any elongation

I don't agree that you need spikes especially for this wide field vista

I see you are one of a few using IRIS, tried myself once but seemed a bit complicated although I'm yet too see a comparison between say IRIS and DSS as to whether it is much an improvement.

Roger,

Wouldn't that be something, eh?

Next time I image this, there'll be no elongation. Promise!

Quote:

Originally Posted by rogerg

Can you imagine flying in a space ship towards and then just through the stars of M7 and having nothing but a wall of gold stars from top to bottom of your window? Would be quite breathtaking.

Nice colours, shame about the illongation of stars, but the colours, FOV, etc make this quite a thought provoking image

Alex,

You're too kind -- thanks!

Quote:

Originally Posted by alexch

I am running out of superlatives - this is fantastic!

I reckon elongated stars in the corners make it look more three-dimensional and draw attention to the middle of the frame.

Cheers,
Alex

Jase,

Always a good heads-up when receiving a positive comment from you!

Cheers, mate.

Quote:

Originally Posted by jase

Solid work H. The open cluster punctuates the golden star cloud nicely - good processing. Well done.

Thanks, everyone, for checking the image out and commenting.

H

RB (Andrew) · #19 28-05-2010, 02:09 AM

Quote:

Originally Posted by Octane

Andrew,

Cheers! I think your Takahashi refractors will have focusers adequate enough to illuminate the 35mm frame. Where we used to stick to ISO-400 on the older systems, do not be afraid to use ISO-1600 as a basepoint on the 5D Mark II. I consider it to be the standard ISO for astroimaging on that camera. If I had a fast focal ratio system, I'd actually be going down to ISO-200 and doubling/trebling my exposure duration for maximum dynamic range and low noise.

About time you got one. I'm looking forward to the 1Ds Mark IV (if it ever comes to fruition).
H

Yeah I've had the 5D MkII since last Nov, when prices hit rock bottom and my mate (the one I told you about, found him again) got a super deal, so thought I may as well.
Just haven't had the chance to do any imaging with either of the new cameras.

Both refractors will easily illuminate the full frame and I'm hoping to give the 150 first light soon, I'll bung on the 5D II and give it a go too.

Octane (Humayun) · #20 28-05-2010, 02:15 AM

Did you get a CCD? Which one?

H