The astro bug has bitten: rookie Andromeda

I read the stacking tutorial over in the discussion section and wanted to give it a try. I think my first attempt went better than my second!

I already posted my first in the discussion thread. Two nights ago I used the Tamrom 28-75 f/2.8 at 75mm, f2.8, ISO1600, 13" each x 22 light frames + 23 dark:

IMAGE LINK: http://www.flickr.com/​photos/nathmath/498567​3376/

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Nice shots! I'm learningmyself. What do you mean by "light" and "dark" frames?

I was wondering the same... what are light and dark frames. I have an answer in my head, but would rather hear it from elsewhere lol

A light frame is an exposure of the stars. A dark frame is an exposure at exactly the same settings, particularly with regard to shutter speed, but with the lens cap on.

What the dark frame does is highlight hot pixels and noise generated by the long exposures used in astrophotography, which is why it is important to use the same shutter speed and preferably at the same temperature.

Stacking software used to put them all together can use the information provided by the dark frames to reduce/remove the hot pixels and noise from the light frames, resulting in a cleaner image.

Badger49456, very nice, I'll try this with my 15-85 lens at 85mm.

Where is "SL Michigan"?
I show SE Michigan in my profile, but live by M59/US23 area, overhead is sorta dark but nearer horizon I get light pollution effects.

[edit]
M31 directly overhead (almost) 5am, I'm shooting now!

Pretty good for 2 second exposures. You should be able to go longer without star trailing...

Sorarse wrote in post #10912191
A light frame is an exposure of the stars. A dark frame is an exposure at exactly the same settings, particularly with regard to shutter speed, but with the lens cap on.

What the dark frame does is highlight hot pixels and noise generated by the long exposures used in astrophotography, which is why it is important to use the same shutter speed and preferably at the same temperature.

Stacking software used to put them all together can use the information provided by the dark frames to reduce/remove the hot pixels and noise from the light frames, resulting in a cleaner image.

Thanks. That means I can create my dark frames now and stack them? lol

Badger49456;
I'll pp my shots and put into own thread, but you got me outside early this morning...so sharing in your thread.

Located M31, this is 1 of many test shots took @ 15mm trying to center it onto the frame. Centered above the peak of our home.

turkleten wrote in post #10910833
Nice shots! I'm learningmyself. What do you mean by "light" and "dark" frames?

ashleyhanetphotography wrote in post #10911210
I was wondering the same... what are light and dark frames. I have an answer in my head, but would rather hear it from elsewhere lol

Thank you! And thank Sorarse for the explanation.

mtbdudex wrote in post #10912312
Badger49456, very nice, I'll try this with my 15-85 lens at 85mm.

Where is "SL Michigan"?
I show SE Michigan in my profile, but live by M59/US23 area, overhead is sorta dark but nearer horizon I get light pollution effects.

[edit]
M31 directly overhead (almost) 5am, I'm shooting now!

Thanks, mtb. SL is Spring Lake, on the west side of the state. There is a bit of light pollution over here with Muskegon and Grand Rapids being the biggest contributors, but it is possible to make out the Milky Way on good nights.

Edsport wrote in post #10912635
Pretty good for 2 second exposures. You should be able to go longer without star trailing...

Thanks Edsport. Even at 3 seconds I thought I saw some trailing with 180mm, but it might have ended up so negligible that I probably should have extended the exposure.

mtbdudex wrote in post #10913107
Badger49456;
I'll pp my shots and put into own thread, but you got me outside early this morning...so sharing in your thread.

Located M31, this is 1 of many test shots took @ 15mm trying to center it onto the frame. Centered above the peak of our home.


Then as I had almost centered, went to take a shot at 50mm, this effect happened....lens creep!
That what happens when you shoot almost straight up.
Kinda cool, almost Star Trek looking...

I'll do DSS and post in my own thread later....

Not gonna lie, I like the effect!

small world, my sister and brother in law live in spring lake, we visit them 2 times/year.
Love the west side, yea you have more dark skies then where I live.

The second shot is never going to work well, 2'' is just not enough for an untracked shot. Averaging 500 2'' shots is not the same as averaging 20 50'' shots.

The first shot is quite good, I think the background is clipped as the sky is never so dark, the WB seems to be off with a strong red cast in Andromeda and there seems to be plenty of hotpixels around. You can try with some bias/offset frames to see if that helps, just take them at the same ISO1600, lens cap on and 1/8000 speed. Maybe that helps.

Cheers
Luis

looks really good

Went out again last night with the 28-75 at 2.8, 10 second exposures this time and ISO 1600. I finally got an intervalometer which makes life easier. I really need a decent tripod and a tracking mount!

IMAGE LINK: http://www.flickr.com/​photos/nathmath/503755​6006/

What software is used for stacking and can you provide a link?

primnumbers wrote in post #11012352
What software is used for stacking and can you provide a link?

I think it's Deep Space Stacker.

Here's the link for the free download for the freeware:
http://deepskystacker.​free.fr/english/index.​html