stacking NB and RGB

[blink138]

hello members just getting my imaging train up and running again and i would like to know a few things
i have a baader 7nm narrowband 2 inch with my 60da
do i expose until the red channel is in the middle of the second column a la normal RGB?
the exposures and iso are very long and high for this
DSS normally will not stack different iso and exposure time, how is this done and how do i mix them?
regards
pat

[MrB]

Hi Pat,
Yep with NB filters on OSC, the exposure lengths go way up.
With Ha I do 15, 20 and 30 min subs usually, staying at ISO400 or 800 if possible.
When checking the histogram, make sure you are looking at the histogram for the red channel only (another press of the 'Info' button on the Da). If you only check the overall histogram, the red channel will end up overexposed and you'll have blown highlights.

I've never tried to combine Ha+RGB, so can't advise.
As for DSS, I'll also leave that to someone else, I tried to use it for a while and hated it.

[blink138]

thanks simon
pat

[rustigsmed]

hi Pat,

wouldn't you stack your Ha and RGB separately (DSS) then copy and paste the Ha red channel into the red channel of the RGB using appropriate blending? (Photoshop)

You may want to do a star mask beforecopying the Ha over...

keen to see how it turns out!

Rusty

[blink138]

i have read that you replace the red channel in the RGB with the Ha data?
but i still do not know how to achieve this
pat

[rustigsmed]

what photo editing software do you use?

You could replace or combine so the red is a HaR channel.
Why not try both and see what the difference?

[blink138]

i think that is what i will attempt to do russel
i only have the dss and PS elements, however i put a post here on iis about astro softwear and a lot of people say the pixinsight is the way to go
i will look into this programme a little more vigorously in the near future as it is imaging time again!
pst

[rustigsmed]

Photoshop will blend it easily, I assume elements has the 'channels' heading but yes I'll be getting onto pixinsight soon also ... Although I still think a lot of people use ps in conjunction with pixinsight.

Looking fwd to seeing the result!