First L(Ha)RGB and some galaxies

[allan gould]

Had a ball on Monday night and finally recovered enough to have a go at processing my images. I was wondering how the QHY8 would go at 2x2 imaging of galaxies with my 5" ED APO refractor and how much I could get at 2x2 binning using a Lumicon Ha filter (Night Sky). Since the QHY8 was used with the IR filter in place this gives ~30-40nm effective Ha filte The moon was full bottle for the M42 shot (LRGB) colour shot native and L(Ha) done at 2x2 binning. I also photographed NGC253, NGC 613 and NGC1365 (plus companions) in moonlight and right into the light pollution of Brisbane.
Had an absolute ball as guiding was perfect after using Alignmaster. About 1 dec correction every 10 min. I need more depth to these shots but it was purely an experiment to see what happens with 2x2 binning(Nebulosity) and if I could do Ha and combine this with LRGB.
Comments welcome.

[AlexN]

Good going Allan. The M42 shot looks a little dim to me, but the colour balance seems good and the details are beautiful.

I've found with an OSC camera, Binning 2x2 for Ha is not the best way to do it.. by binning 2x2, you're getting all the bayer matrix colours (RGGB) in one pixel... If you take a 10min Ha sub Bin 1x1, then open the colour image up in Photoshop, take a look at the green and blue channels, they will be mostly noise, with a hint of information (because at 40nm you're letting in plenty of other light..) Binned 2x2, all the noise that would have plagued the green and blue channel will be trapped in the image with the Ha data...

Since I worked that out I take all my OSC Ha filtered data at Bin 1x1, stack the subs with full calibration frames, then when it gets opened up in photoshop, I will extract the Red channel only, and save that as the Ha data. I then combine that with my RGB data.

Here's an example shot of M42 I did in Ha last year with my QHY8 (Same Lumicon Night Sky Ha filter and the UV/IR filter giving me about 40nm Ha) That is 8x600s + 13x30sec with no darks, just flats and bias frames used, Bin 1x1 and R channel extraction..

[madwayne (Wayne)]

A very nice collection there Allan. I think your M42 is super, very natural and not over processed. Your dim fuzzy collection and labelling is right up there too.

Thanks for sharing them with us.

Wayne

[multiweb (Marc)]

That looks real cool Allan! My fav is the sculptor galaxy. So sharp. Real tidy. Top work.

[Craig.a.c (Craig)]

Love the pic of M42. All those "fuzzies" in the second pic is amazing.

[allan gould]

Originally Posted by AlexN

I've found with an OSC camera, Binning 2x2 for Ha is not the best way to do it.. by binning 2x2, you're getting all the bayer matrix colours (RGGB) in one pixel... .

Thanks for that Alex - yes its a little dim but I was primarily looking at 2x2 binning and was just interested to see what the filter could do. I agree that the G&B channels have just added noise to the Ha channel and next time will go the full bottle with the Ha.
I was also interested in the QHY8 capabilities with the 5" refractor. Too many objects and not enough time. I cant resist the temptation to flit from one object to another and just get some data. I guess that I have to be more disciplined and pick one object and just spend one night or several imaging that.

[AlexN]

with a permanent setup, there's no reason not to spend 3 nights per target.. Or even 3 nights collecting ha data during the full moon cycle and 3 nights collecting rgb data during new moon. It does appear that the qhy8 and the 5" work very nicely together..

[telecasterguru (Frank)]

Allan,

I am most impressed. This gives me lots to think about.

Frank

[renormalised (Carl)]

Very nice set of piccies...well done

[Hagar (Doug)]

Nice collection of images Allan, Good to see you have the QHY8 out of the box.
Very nice keep them coming.

[spearo (Frank)]

nice work
well done
frank

[peter_4059 (Peter)]

Great collection of images Allan. I particularly like the M42 - great effort.

Peter