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Jannis

An old M27 with some new data added

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Back in 2013 i captured a nice image of this nebula that i was very pleased with. However, it strongly lacked red as my unmodded 550D filtered it all out. 

So here the other day, trough some fog, i managed to capture some Ha data with the help of the QHY5L-II-M and a Baader 7nm Ha filter with the explorer 200. 
Exposures were limited to only 60 sec as i was capturing unguided, and even then i had to throw away half my subs (i really need to have my mount chacked and serviced...). 
Captured using Firecapture, with gain set at 1000, and peltier cooled the camera to about -20c. 

RGB data from 2013: 1 hour 45 min @ ISO800.
Ha data from this week: 47x 60 sec. Gain 1000.

I think the Ha data helped a lot to bring out more red color and details. What do you guys think?

Original RGB from 2013:
m27-sgl.jpg

Ha data from the QHY5L-II-M:
M27 47x 60s Ha.jpg

New HaRGB:
m27-revisited-akam-sgl.jpg

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The HA makes the edges of M27 Burn- very nice. How did you add the HA?- let me know I'm always looking to compare notes. I use PixInsight Pixel math to merge the HA directly into the red channel but I know there are other ways.

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Thanks. :)

I only use Photoshop to process my pictures. To blend in the Ha data, i first extract the red channel from the RGB and open it as a new picture. I then add the Ha as a new layer. After roughly adjusting the levels and curves, i duplicate the Ha layer, run a light (usually 2-10) high-pass filter on it, set it to overlay and merge it down to have a Ha layer with some increased sharpness and details. I then duplicate it again, and used a mix of lighten and screen (with layer masks applied to not burn out the core) when merging it with the R-channel. 

After this i simply copy the new HaR-channel and paste it back into the R-channel of the RGB picture. 

There might be many other ways to do it, and i have no idea is this is a good or bad way to do it, but it seems to have improved my picture significantly at least. :)

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