A wide field woose speedy red cat

[strongmanmike]

This image combines data from two optical systems and frames the famous Cats Paw Nebula in Scorpius.

As already discussed, this nebula appears a deep red colour due to significant amounts of intervening dust between us and the nebula.

Although subtle, there was some colour variation present in the RGB data too which I tried to showcase as well :)

Details of the two data sets can be found under the image:

Wide Field Cats Paw (http://www.pbase.com/strongmanmike2002/image/156586669/original)

[astronobob]

Sweet Image Mike, diggin them blue stars everywhere, really sets off the Red Neb :cool2:
I no have CC but only a question , in a word - how does two scopes benefit an image - not that i wanta try it :confuse3: :thanx:

[strongmanmike]

Hey cheers Bob. :thumbsup:

Even though they have similar focal lengths, The 6" Starfire APO with the big 16803 chip has a much larger field than the AG12 gets with the smaller sony chip in the Starlightxpress. The AG12 data is higher resolution, showing more fine details than the Starfire too due to having a larger aperture, the pixels being smaller and the seeing is better here in Canberra than it was in Newcastle, so the details immediately around the paw pads themselves is increased over what the original Starfire only image showed.

Mike

[Rod771]

Great combination of data Mike! :thumbsup:

I have a question too. When adding new data to old do you integrate all individual subs together again or just combine the old master to the new master (or old master to new individual subs) ?

[strongmanmike]

Interesting question, I have done both depending on the quality of the data. When integrating higher res data with lower res data the key is to do it in a way that isn't obvious, usually the higher res data stands out and you will see this effect in some Orion region composites for example, the higher res data used for M42 or the Trifid stands out and can make the image look odd not to mention the diffraction spikes that are only in one set of data. So blending finesse is paramount :) In this case the data resolution difference wasn't huge so getting a natural looking blend was easier and the diffraction spikes present in the AG12 data set are not too obvious :thumbsup:

Mike

[cometcatcher]

I really like this one. Interesting that the FLI camera needs darks where the Sony doesn't.

[strongmanmike]

Glad to hear it :)



Just different chips, the 16803 is still a fairly clean chip (HERE (http://www.pbase.com/strongmanmike2002/image/123074113/original) is a 10min dark at -30C)but is a just little noisier than the Sony, I could probably just dither and median combine with it too but I never tried :question:...if I put the big Proline back on the AG12 I may try it just to see, of course the big 16803 chip does need flats due to vignetting.

Mike

[cometcatcher]

That's very interesting. There's still a few hot pixels left even at -30C. Goes to show how important cooling is. No wonder my DSLR sensor is horrendous at +30C.

[gvanhau]

Very nice result.

How do you compare the performance of the APO against the reflector?
Knowing the cuality of the AP refractors I think it outperforms the AG12 in terms of resolution or am I wrong?

Geert

[IanP]

Mike, it's beautiful image and exemplary processing !!!
:thumbsup:




@+30 deg these things produce "Picasso-style" images by themselves ...
:rofl:

[strongmanmike]

Of course that is a 16 Million pixel array... but in comparison the 6 Million pixel H694 has less than half a dozen hot pixels across it's entire surface!! :)



I was not expecting it either Geert but after having used both scopes for significant periods now and in mixed conditions across many of the same objects, I can confidently say, yes, the Astrophysics pedigree is indeed top of class but the AG12 even at F3.8 still outperforms it slightly in the overall resolution department, especially under good seeing conditions.

For example

Compare this AG12 image (http://www.pbase.com/strongmanmike2002/image/151629696/original) with this AP152 image (http://www.pbase.com/strongmanmike2002/image/101280698/original)

or this AP152 image (http://www.pbase.com/strongmanmike2002/image/129977473/original) with this AG12 image (http://www.pbase.com/strongmanmike2002/image/155066472/original)

The speed with which the AG12 gathers signal is very noticeably better than the Starfire too.



Cheers Ian, yes cooled CCD's are certainly very handy, especially in summer :thumbsup:

[RickS]

Nice, seamless blend Mike! It does look nice with a bit of space.

[strongmanmike]

Thanks Rick, yes NFW or WFW both have there pluses :thumbsup:

Mike

[Bassnut]

Crafted to your standards Mike, well blended.

[strongmanmike]

Thanks Fred, bit of fun processing :thumbsup:

Mike

[ReaPerMan]

Great image Mike. The additional hires detail is great. Love that FOV very similar to the 1 degree or so that I get on my 11000M.

Two thumbs up :thumbsup::thumbsup:

all the best

Paul

[DJT]

Nicely done, Mike. The blues came through well.

[astronobob]

Wow, your explaination is very understandable, what a grouse concept - the best of both views in the one Image. Definately worth the excercise then !!
Thanx for that Mike ...:thumbsup:

[prokyon]

Great work Mike, you know how to do. Fantastic colors!

[gregbradley]

Hybrid images are a great way to get extra life into an image which you have done here.

Greg.

[strongmanmike]

Thanks for checkin it out fellas, I'm quite happy with the finished product actually....must work out how to get the Starfire and AG12 running in tandem :question:...would be good to have both data sets for all objects :thumbsup:..the fields of view are rather different though so would need another bigger chip camera..hmmmm?? :confuse3: :)

Mike

[xelasnave]

There are few superlatives I could offer other than that is wonderful.alex

[strongmanmike]

Hey cheers Alex, nice to hear :)

Mike

[SkyViking]

A wonderful combine of your two great images Mike, the Cat's Paw looks really good here!

I was hoping to finally get some blue channel data for my own pending version, but only managed to collect 4 frames before clouds rolled in again :rolleyes:
But it's looking better tonight, so there is still hope :)

[strongmanmike]

Oooooh.. I see another collaboration possibilty :D

[tilbrook@rbe.ne]

That's awesome Mike!!:thumbsup::thumbsup:

How did you scale the two images to stack them together.

I usually use the suck it and see method in PS.

Must be a better way.:question:

Cheers,

Justin.

[strongmanmike]

Cheers Justin

I preprocessed the separate data sets and then coregistered the AG12 data set to the AP set in Astroart5 so they matched. I then created several versions of each with different levels of dynamic range and resolution and blended them all in together using layers in PS - that was the tricky bit, ie to get the blend looking as natural as possible :) I did the same with my recent Eagle Nebula hybrid image but it was more difficult because the AG12 resolution in this case was more noticeably better than the Starfire data

Mike

[tilbrook@rbe.ne]

Thanks Mike!:)

I've heard somewhere that you can stack images taken with different scopes but the same camera.
Need to look into this, haven't got Astro Art.

Cheers,

Justin.

[Stevec35]

I like it Mike. One of your very best IMHO.

Cheers

Steve

[strongmanmike]

It's not very difficult to do really, most if not all processing software should have a co-register function :shrug:



Thanks, glad you think so Steve :thumbsup:

Well done on your HM at the Malins too :)

Mike

[nandopg]

Hello Mike,
Looking to your image, which by the way is great, I can note some dark material spread out over the center of the paw.
I always had curiosity about it, although is very rare to see it in images posted in the net.
Then I decided to dedicate 2 nights to image this nebula and process it basically to avoid any compression of the dynamic range of the RGB and Ha data, as well as the LHaRGB data . I simply got a result totally different from that one normally is seen.
I don't want to bother you, but if you don't mind, would you please have a look on my outcome and let me know what do you think ? The link to the image is:
http://www.astrobin.com/full/106733/0/

Thank you Mike,
Fernando

[strongmanmike]

Hi Ferni :)

Hmm?..It looks ok to me, I just increased the colour a bit more than you and showcased the Ha emission. I assume that is an LHaRGB combine? How much Ha is in your image and how did you incorporate it in your processing?

Mike

[nandopg]

Hi Mike, thanks for your considerations.

Yes, the image has some Ha data blended to the luminance and red channels following the combination:
Luminance Final = 0.6*L + 0.4*Ha
Red:
0.6*R + 0.4*Ha for normalized pixels between 0.7 and 1
0.7*R + 0.3*Ha for normalized pixels between 0.5 and 0.7
0.85*R + 0.15*Ha for normalized pixels between 0.01 and 0.5

After the blending I did a new color calibration to make the star's colors right and got the image.

That was the procedure I used. Would you see something suspect or something that could be better done or differently?

Best Regards,

Fernando

[strongmanmike]

Geee..that's a tough one :question:...your blending ratios are actually similar to mine really, although I don't asign the different amounts based on normalised pixel weights, but I do make many variants that I blend together until it looks like an enhanced richer version of what my RGB data is showing me...probably not scientific but generally quite effective ;)

Mike

[troypiggo]

Love this nebula, love your rendition of it.

[marco]

Lovely Cat's paw Mike, great to see data from different scopes and time blending in so smoothly :) I like the color balance too..

Clear skies
Marco

[strongmanmike]

Cheers Troy and Marco, glad you both liked it :thumbsup:

Mike

[Paul Haese]

I like the wider field of view Mike. The image now incorporates some of those really nice dark nebulae around the Cat's Paw. Any thoughts on doing a full NB on it? Do you know if there is much OIII in the CP?

[RickS]

There's a very small amount of OIII, Paul, just in a few spots. I know because I've been collecting many hours of it ;)

[strongmanmike]

That's what I would have thought too...should be an interesting shot Rick :thumbsup:...man! you haven't posted a completed image for aaaages...me thinks some M E G A data (hear thunder! hear lightning!) is on the way I guess :lol: ;)

EDIT: Oh yeah you did - M51...but that was with a remote sit and sleep scope so doesn't count :P :lol:

Mike

[NOMH]

That's a great image Mike. A lot going on there and you did well with the stars, detail, and colors!

JB

[strongmanmike]

Thanks JB, in this age of doing exposures measured in days rather than hrs and using artistic narrowband data to create wonderful 3D images of nebulae, this image is just a nice simple true colour image of a deep sky field with all the basics of processing (with only a few tricks) addressed :thumbsup:

Mike

[Ross G]

Hi Mike,

I've been off the scene for a while so it's so nice to come back to beautiful photos like this one.

The Cats Paw is a great looking object and your photo shows it well...love the colour and detail.

It's good to see your high standards are still the best!

Ross.

[atalas]

Wow....that looks good even on my uncalibrated crap monitor! well done big guy.

[andyc]

Lovely detailed image (not that you seem to produce anything less!), and it was also interesting to read the snippets about how you combine the different datasets :thumbsup:

[strongmanmike]

Hello Rossco :hi: where you been at? Thanks for the kind words :)

Not a lot of variation in the colour of this one but there is some if you are careful with the processing :thumbsup:

Mike



Thanks Louie, who needs a calibrated monitor anyway? make for more fun :lol:

Mike



Cheers Andy glad you liked it

Mike