Here's a quick and dirty shot of Orion's Belt and the Flame/Horsehead Nebulae area using a few test frames that I shot for a 2 am demo of Deep Sky Stacker at Chris' (hotspur) fabulously dark-skied home. Comparing against prokyon's amazing image, I can see that a lot of the fainter nebulosity is starting to come through.
Details: 38x 59 sec subs at f/4, ISO 6400 using a Canon 5DmkII mounted on an Astrotrac. Darks and bias frames were shot and used in the stack, but I messed up the flats by accident.
I didn't polar align the mount properly (just eyeballed the SCP against the Milky Way and LMC/SMC) so the stars were already eggy at one minute (hence the crazy ISO).
In case any other fellow beginners are interested, I've posted a straight-out-of-camera sub that has no processing other than RAW conversion and resizing. I've also posted a screen shot of DSS when it was finished stacking. I imported the Autosave.tif file into Photoshop, stretched the histogram using Levels (48, 1.10, 125), added a bit of Saturation (+15), resized and saved.
Just for kicks, here's a straight-out-of-camera shot of the Flame and Horsehead Nebula through my 132 mm apo refractor taken in my light polluted back yard. Can anyone even spot the Horsehead?
Thanks Dave!
Like how you have the 'Start Button" in the top right hand corner!
(I have mine in the top left)
Anyhoe.....
Great that you have shown us ( newbies) the different stages of processing!
Dave, if you could do some sort of tutorial for the new comers here, in using DSS and your set up that would be great!!!!!
Thanx
Bartman
That's a really good idea - a very basic, step-by-step tutorial with lots of pictures for people new to using DSS (and stacking in general) with a basic dSLR set up.
I know that I was horribly confused with DSS to begin with (and I'm a software engineer!) but it becomes very easy to use with a bit of practice.
If it ever clears up around here, and I get a bit of free time, I'll give it a go.
Here's a shot of the Large Magellanic Cloud that I took while setting up for the comet on Christmas morning. The mount wasn't polar aligned at all yet, so I was limited to very short subs before star trailing occurred.
Details: 45x 10 sec, f/2, ISO 6400 with a stock Canon 5DmkII and Canon 135 mm f/2L mounted on an Astrotrac.
A lot of the internal/central structure is already visible despite such little data, but it wasn't quite deep enough to bring out the spiral arms properly.
That's a really good idea - a very basic, step-by-step tutorial with lots of pictures for people new to using DSS (and stacking in general) with a basic dSLR set up.
I know that I was horribly confused with DSS to begin with (and I'm a software engineer!) but it becomes very easy to use with a bit of practice.
If it ever clears up around here, and I get a bit of free time, I'll give it a go.
That image looks good Dave,well done!
Yes,a tut by yourself would be well received!.thanks for the little one you gave in observatory at 2.30am,while cloudy.
If you ever wish to use the scope and gear in my observatory with your 5d,you are most welcome.I also have another scope and tracking that goes outside that can be used.
Great to meet someone so keen!,Never had anyone arrive at 9 pm after a two hour drive and then leave before 7 am the next morning!,Great dedication.
I've been seriously considering dropping the gear and going with a simple astrotrac setup. So portable.
How do you find it to use? I'm thinking I would probably get out more if my setup was easier to lug out to the darker sites.
It has been fantastic this past week or so with the comet chasing in dark skies (here, here, here, and here).
My EQ6 is obviously a far more capable beast, easier to adjust (polar alignment, changing directions, etc) because of its size, and much cheaper, but for portability and wide fields the Astrotrac is brilliant. I really hate packing up the EQ6 at dawn (heavy lifting + sleepy = unhappy me) but the AT is light and easy. Worst case scenario, I can just lift up the whole thing and throw it into the back of my van.
I have the whole kit (mount, polar scope, wedge, pier, head) - I'm unconvinced by the polar scope and head at this stage, but the rest is great.
It obviously depends upon the focal length and exposure times, but at say less than 50 mm full-frame-equivalent focal length for less than 3 minutes, I find that it's enough just to eyeball the SCP.
With careful compass alignment I can get up to 1-2 mins @ 200 mm without trailing. Others have reported about 3 mins using the polar scope.
The longest exposure I've taken without trailing is 7.5 mins @ 50 mm using a quick drift align assisted by PHD (i.e. <= 1 pixel drift after 20 secs on my Orion ST80+StarShoot auto guider).
Thanks for the excellent info. My question wasn't very clear, but that was a bonus as I scored some extra info
What I meant to ask was what is the procedure for polar alignment like, is it fiddly or difficult. I take it you don't have the polar scope then?
I was thinking of a setup with a guider as well, and was looking to do wide field and up to about 200mm, maybe strapping lenses onto the front of a QHY8.
I'll start a new thread, as I'm dragging this way off topic.
