Rosette HaLRGB with Tak FSQ106

[cventer]

Rosette Nebula taken over 2 nights a few weeks back from burbs of Melbourne

Finally got around to processing it. Did not get enought RGB data with FSQ so blended it with some RGB data from my Tak FS-102.

Scope: Takahashi FSQ at f5
Subs: 15 x 10 min Ha (Astrodon 5nm), 12 x 8 min Lum, 20 x 5 min RGB (Astrodon Gen 1)
Camera: SBIG ST2000XM
Guide scope: 50mm Finder Scope
Guide Camera: Orion Starshoot
Mount: Paramount MX

Processing: Calibation, Alignment, Normalisation, Data Rejection, Stacking in CCD Stack. Finishing in photoshop with, levels, curves, shadows/Highlights,Multi Layer High pass for large and small frequencies, Noise Ninja

Attached is HaLRGB small version, plus the 2.5 hours of Ha data.

Large Version HaLRGB at 1600x1200 Here

Hi res of Ha Here

All images uncropped. Did I mention how much I love this scope

[LucasB (Lucas)]

You must be enjoying that scope! Really like the Ha picture. Has nice detail!
Lucas

[Paul Haese]

Nice image Chris. Maybe just deal with the dark rings around the blue stars. Other than that looks good.

[Mighty_oz (Marcus)]

Very nice Chris, have u got a link to hi-res of the Ha ?
Too hot over here in Perth to image so i'm playing with t-point etc

[ballaratdragons (Ken)]

Terrific result Chris!
The detail is superb.

I can easily see the Cheetah Nebula

[cventer]

Originally Posted by Mighty_oz

Very nice Chris, have u got a link to hi-res of the Ha ?
Too hot over here in Perth to image so i'm playing with t-point etc

Sure here is Hi res of Ha Here

[gregbradley]

Very detailed and sharp Chris. You are extracting the performance out of the sharp optics there.

Greg.

[cventer]

Originally Posted by Paul Haese

Nice image Chris. Maybe just deal with the dark rings around the blue stars. Other than that looks good.

Thanks Paul,

Yeah agreed I overdid it on mimimum filter in the RBG layer. Trying to match different size stars from Ha and LRGB is allways a pain and something I have not figured out how to do properly yet.

[Paul Haese]

Originally Posted by cventer

Thanks Paul,

Yeah agreed I overdid it on mimimum filter in the RBG layer. Trying to match different size stars from Ha and LRGB is allways a pain and something I have not figured out how to do properly yet.

Yeah me too on some objects. Not all objects can be processed the same as far as I can tell.

[TrevorW]

Nice effort on this one

[Ross G]

Great photo Chris.

So sharp and deatiled.

Colours look great.

Ross.

[RobF (Rob)]

Wonderful crisp sharpness, but doesn't look you've had to try to pull it out at all. Great start with what sounds like a top rig.

[gregbradley]

Originally Posted by cventer

Thanks Paul,

Yeah agreed I overdid it on mimimum filter in the RBG layer. Trying to match different size stars from Ha and LRGB is allways a pain and something I have not figured out how to do properly yet.

Minimum filter is rather a destructive filter and its use is severely boundaried as a result.

Deconvolution on the r g and B subs or luminance or even the Ha is a better solution.

Try CCDStack and positive constraint 40 to 60 iterations.

You don't need to match star sizes with Ha anyway as you don't want Ha red stars bleeding through in the final image only the rgb stars.

So you use lighten mode for the rgb layer and that should mean rgb stars and colours should shine through or you use curves to boost them so they do break through the Ha layers set to red (perhaps only 50% opacity to suit the image and blue (10% opacity).

I have tried to match FWHM star sizes between LRGB masters and that can work but probably more important to match FWHM sizes between RGB (blue usually being worse FWHM values). That can reduce the colour halos you can see in some RGB images in stars. Luminance is typically lower FWHM values and that doesn't seem to matter to the final LRGB stars as far as ringing goes.

Greg.

[strongmanmike (Michael)]

The Ha is great Chris, some great detail there - amazing to think what can be achieved in this age of imaging from inside a large bright city ...good times

Greg has given some good advice there, I like to make various blends of data with the Ha and then combine with the RGB and then re blend again and again until the stars match. I did it almost perfectly on the Hubble palette version but I too had some residual halos in my Tunnel of fire, not really objectionable but there none the less.

Mike

[cventer]

Thanks all for nice comments and for advice.

Mike and Greg I will give it a shot to repro the color with some of those tips when I get some time.

Thanks

[Paul Haese]

Chris, just out of interest which Ha filter are you using? I got similar halos on the bright stars and I am using Astronomiks 12nm Ha filter. Those big halos look large reflections on my Ha subs.

[cventer]

Mine is astrodon 5nm

I dont have those in my Ha image though which I added a link to so I am pretty sure its my RGB processing