First Attempt at a Galaxy - NGC 5239 Southern Pinwheel
This is my first attempt at a galaxy
NGC 5236 Southern Pinwheel Galaxy
Moon was still up at around 15 deg when I started at 12.30am so the first 10 or so subs had heaps of moon light. Finished imaging subs around 3.30am , set my darks and went to bed
40 x 3 minute subs
10 x 4 minute subs
20 x darks
ISO 800
PHD2 guiding ( 1.00 to 1.40 arc sec error )
Canon 600D stock ( sensor temp was 32 deg still very warm )
Stacked in DSS
Processed in Startools
Can’t wait to image this galaxy again at the next dark and a cooler night to give the DSLR a chance
Good first try Martin. The noise is horrendous; I suggest that as you are guiding, and therefore the stars remain pretty much stationary, that you
dither [as recommended by Rowland in another thread].
The colours are a bit odd, M83 is predominantly blue with little vivid patches
of Ha red dotted about here and there.
raymo
Yes it’s full of noise , long hot DSLR subs with the moon glaring behind me and a warm night not a good combination
Oops with the colour , I used M51 instead of M83
What the heck , have it a go , can only learn from this and improve
Thanks for the comments and dithering is next noise reduction feature to try
Cheers
You've captured some nice detail there Martin. The colour will be an easy fix, a good start to your galaxy collection, I'm sure your next one will be a huge improvement - not to say your first isn't good, in fact it's very good. Great start and keep them coming!
Looks great Martin, with the noise use less is more in the life module at about 35%. It'll help get rid of the noise, as well as on final noise reduction bump the pixel up to 10 plus. Once it's done that use the smooth tool a little to smooth it over, it doesn't harm the detail of the galaxy.
Thanks Mick and Karl
I kept at ISO800 to keep the read noise down but with longer subs you expose more detail but gain more noise so it’s a catch 22 , it wasn’t a good night ( morning) to image anyway, horrible I fact but gave it a go anyway
I usually use default setting 4.5 for noise reduction and bump up the read noise compensation but should try to be more aggressive with the noise reduction, although there is a limit as you can start to lose good data if you push to far
I also lassoo’d the galaxy core when I used wipe but I found no difference between isolating it from Wipe or including it Wipe ?
Galaxies are another beast not like nebs and clusters
Heaps more to learn but I’m happy with this first Attempt
Thanks again
Cheers
Nice Galaxy capture. Yes it's noisy but you knew that when you posted in you original post that the sensor temp was high.
The way I see it, we could all wait for the perfect image that never really comes along or we can all post our progress and enjoy the journey together. I prefer tha latter
Thanks Ryan
This time reprocessed again in Startools
Re cropped
Restretched
Wiped
Life module using use less more @ 25%
Colour - corrected for M83
Noise reduction increased to 8
Looks a bit cleaner than the original but not as sharp as it’s been cropped and resized etc
Still more work to do
I think it was 200% or 250. Most images I bump it up, I don’t normally use the default setting of 100%
I should write down my workflow or take photos as I work through for future reference on similar images
Thanks Alex
Appreciate it
Can’t wait until we get a dark sky next week ( no moon ) and a cooler night for the DSLR that should help with noise and allow me to adjust ISO and exposure time to capture improved subs and more subs
It’s really exciting to capture your first galaxy, their dim little buggers !
Thanks Roy
Yes if you can find it , frame it and capture heaps of longish subs with good focus and guiding you will surprise yourself
Be prepared for a late night/ early morning at the moment
I probably will wait a few weeks until I try to image it again in the dark with no moon around earlier in the night
Good luck
Thanks Tony
If I knew what I know after processing this image I would have started around
2.00am as the moon glare was almost gone and the night was slightly cooler
The image may have been a tad less noisy
You should have seen the image when I opened it after my first stretch , blue haze with all sorts of rubbish and big halo in the background , you could hardly see the galaxy it was a whitish blue blob
Startools did a great job of cleaning it up
Yes the 600D suffers in summer but it’s still a great camera, ongoing to keep using it for a while yet before venturing into CCD territory
Thanks again