M51 - The Whirlpool Galaxy - HaRGB - WIP

[martin_h]

Star control here ....... http://stargazerslounge.com/topic/223750-star-control-the-u235-method/

[Martin Meredith]

I love the gorgeous mono shot in post 10. Why not just stick it in a frame and forget about the hassle of colour?     

Semi-seriously, maybe I'm weird but give me Burnhams over Deep Sky Wonders, or the Palomar plates over Hubble any day….

Martin

[Gina]

Don't forget that Deep Sky Stacker can also create a starmask suitable for importing into a layer mask in PS.

Here's how to create a star mask in PS

http://www.dens-astropics.org.uk/page%2021.htm

I didn't know DSS could create a starmask   Thank you for the link

[Zakalwe]

I didn't know DSS could create a starmask   Thank you for the link

http://deepskystacker.free.fr/english/userguide.htm#creatingstarmask

[Gina]

Thank you everyone   I'll check out those links

[Gina]

Clear tonight so adding to the Luminance though I think I also need to add to the RGB.

I've taken one sub and processed it in Photoshop.  Curves, Levels, Noel's Make Stars Smaller x3, Noel's Deep Space Noise Reduction x2.  Cropped to around 1200 px square and saved in PNG format.  Seeing seems a bit worse.  I had a good go at focussing.

[ollypenrice]

Don't apply noise reduction globally, I'd say. It will blur seven bells out of your good bright data. Only apply it to the faint stuff. This is where layers come in. Sharpen what's bright (but not stars) and, if really necessary, noise reduce what's faint. 

Olly

[Gina]

Thank you Olly   That's very useful   I didn't realise noise reduction would blur my data.  Must do layers

[ollypenrice]

Call it what you will, NR is a blurring process. Colour NR can be less invasive because it also involves reduced saturation on small scales.

As ever, the only clean NR processes are more data and dither.

Olly

[Gina]

Thanks Olly   I have now collected 38x10m Luminance subs unbinned and now changed to capturing RGB.  I may collect more Lum another night.  I'm wondering whether to go for longer subs and mask off the saturated centre parts.

Here's the 38 L subs stacked in DSS and processed in Photoshop using curves, levels, a touch of sharpening and Noel's Make Stars Smaller x2.  Cropped to be just less than 1200px square (size limit here) and saved in PNG format.

[nightster]

I am loving this thread. Watching each piece fall into place. Better than an hour long drama on television. Come over to my house tonight, I'll make the popcorn. We will watch Gina capture and assemble M51 in LRGB.

[Gina]

Thank you Jeff, that's very nice

[Adamar98]

I'm also loving this thread. The things you learn from having a nosey at a picture. It's coming along great.

[Gina]

Thamk you Adam

[Gina]

Following on from the Luminance last night I captured 12 Red, 11 Green and 10 Blue all 10m binned 2x2 and this morning flats for the luminance - 36 0.001s unbinned L filter giving an ADU around 44,000.  Scope in Home position with white T shirt over dew shield.  Works just as well as a flat screen and a lot cheaper

[Gina]

Been trying Denis Isaacs' method of star masks but it's not working for me   There seem to be some differences from the version of Photoshop he used and what I have (mine is CS5).  I've been through his instructions and ended up with a totally white image   I'lll try something else...

Later... The use of the Magic Wand just seems to flash the image - can't see the point.  So I tried creating am image with the stars only and seemed to succeed but the mask consisted of 3 layers.  I'm confused - maybe I'm getting too old for this complicated processing

[Gina]

Persevering...  I took the aligned luminance stack and loaded it into DSS.  Then created a star mask which seemed to work.  Only thing is, the star mask image looks like it's either reversed left to right or rotated 180 degrees vith respect to the original image loaded into DSS   A large star to the right in the original is on the left in the star mask

Now if only I could remember how to use masks...

[Gina]

Given up on masks for now and decided to do what I could without.

[nightster]

Teamviewer for remote control?  It supports Linux! I will definitely be checking out that one as would be nice to monitor and control from indoors.

[nightster]

Love the yellow/blue contrast with the brown dust.   What focal length did you use on this?

[Gina]

Thank you   Focal length was 1000mm.

[Gina]

Been examining my data and I definitely need more to bring out the halo round M51B.  When we get the next clear night I'm planning to increase exposures to capture the halo and then, when I've sorted out masking, I should be able to blend in the halo with the rest.  Forecast is not good for the next week or so but what do they know?  Things change!

[toxic]

that is looking great Gina

[Gina]

Thank you Chris   It's coming on - so far so good