Widefield astro ?

[SAW]

Hi,

How would I go about processing wide field astro images if I was using my tracking mount to get multiple images of an object in the sky but I also wanted some of the foreground in the shot ? Would I do my normal tracked set of images for the sky stuff, a single image of the foreground and then combine the images ?

Are there any tutorials on this ? It's something I've wanted to do for ages but don't know where to start. I do plenty of deep sky imaging but never tried wide field with the foreground in the shot.

Thanks.

 

[IanSG]

I think the devil's in the detail - how much movement has the tracking introduced and how well lit is the foreground?  If you can get close enough, you could try taking a torchlight shot of the foreground or maybe try a day for night shot.  What were you planning on imaging - you mentioned "an object", but unless you mean the milky way I can't think of anything that would suit a wide field shot.  I've had decent results processing my wide field shots in LAB.

[John Rostron]

Other astrophotographers have run into trouble when including backgrounds in multiple sky images. The problem comes when aligning the images when stacking. The alignment algorithm can focus on the background-sky interface rather than the stars. I would advise removing the background from your images before stacking (or possibly blurring the background-sky interface). You can add the background in later should you wish.

John

[HeinzBie]

Hi SAW,

when you have plenty of time then go to the location you have selected for your milkyway shot (use Photopills and/or Planit Pro  on your mobile to optimize this decision) early, i.e. before it gets really dark, mount your camera and make some blue hour shots with focus on the foreground and low ISO. Wait until the stars get out and then make your milkyway shots as usual. At home stack your MW shots (with Sequator or DSS) and combine the result with the blue hour foreground shot, which is optimal as the colors will fit together without much tweaking.

I made this picture that way: https://www.instagram.com/p/B5bIty9BtSU/

Hope that helps and clear skies!