You don't need a telescope

Me too. That's why I asked. That's quite a neat technique. Thanks.

luigis wrote in post #15494555
To Align the AT I use another strange method. First I align the mount and the camera using any bright star or planet, I center the star in the AT polarscope and also in the camera.

Then I do a rough align and start taking 1-5 minutes exposures (depends on the lens) and check if the star trails are centered in the camera, if not I make a correction and repeat. Since the camera and the Mount were previously aligned when the trails are dead center in the camera the mount is pointing exactly to the celestial pole.

I live in the South Hemisphere so no Polaris here.

That looks like a variation on drift alignment.

SteveInNZ wrote in post #15492164
That's interesting Lugis. Would you mind posting an example of the TIFF that you feed to DSS ?
It's always interesting to hear different approaches to solving the same problem.
How do you polar align your Astrotrac ?

archer1960 wrote in post #15495220
That looks like a variation on drift alignment.

Yes, drift alignment also works you can use live-view at 10X and the zoom box as a reticle to place a star and see where it drifts.

Great shots Luigis, quick question... I'm thinking of buying a motorized mount like the Celestron CG-5 GT GOTO as I assume with the Astrotrac you'd have to know where to point your camera after you've done your polar alignment?


A shot of the moon I took in 2010 and post processed to an inch of its life in LR.
1/80, ƒ/8, ISO 100, 400 mm

On the night of the 21st the Moon, Jupiter, Pleiades, and Aldebaran will all be in a tight circle. I'm hoping for clear sky that night, but for me I don't think it will happen. Good luck to those that can get pics. Here's a link to see.

http://www.skyandteles​cope.com/observing/hom​e/187468741.html

Excellent Moon, superb exposure and I really like the color. Beautiful photo.

On your question: The astrotrac is sandwiched between two tripod heads, typically a Manfrotto 410 or 405 below the mount and a ballhead on top. You use the 410 to polar-align the mount and then you use the ballhead on top the AT to point the camera at your target of choice.

It I wasn't clear remove my UV filter.

cainey wrote in post #15508636
Great shots Luigis, quick question... I'm thinking of buying a motorized mount like the Celestron CG-5 GT GOTO as I assume with the Astrotrac you'd have to know where to point your camera after you've done your polar alignment?


A shot of the moon I took in 2010 and post processed to an inch of its life in LR.
1/80, ƒ/8, ISO 100, 400 mm

m81 and m82- 250mm, f5.6- 21mins worth of exposure piggybacked

luigis wrote in post #15511144
Excellent Moon, superb exposure and I really like the color. Beautiful photo.

On your question: The astrotrac is sandwiched between two tripod heads, typically a Manfrotto 410 or 405 below the mount and a ballhead on top. You use the 410 to polar-align the mount and then you use the ballhead on top the AT to point the camera at your target of choice.

It I wasn't clear remove my UV filter.

Thanks Luigis
I think I may go with a motorized mount then, I know the night sky fairly well but I'll take the easier option.

luigis wrote in post #11180763
Another one:

Nikon 14-24 F2.8 on 5dII, 10 stacked shots each 1 minute.

You're a bloody genius mate.

04yellowf150 wrote in post #15514132
m81 and m82- 250mm, f5.6- 21mins worth of exposure piggybacked

Great shot with 250mm Yellow. Were you aware you've partly cropped a third galaxy, NGC3077, on the bottom edge towards the right side? It'd be worth widening the crop slightly if you have it on the original.

Madweasel wrote in post #15515546
Great shot with 250mm Yellow. Were you aware you've partly cropped a third galaxy, NGC3077, on the bottom edge towards the right side? It'd be worth widening the crop slightly if you have it on the original.

Here is the big image. I see that 1 distant galaxy but according to stellarium it was the NGC 2976 galaxy. I do not know why there is a circle where its lighter, any tips on that? I dont know if its my processing or if its glare from the moon hitting the telescope tube??

Chad,
On the wider shot, you have two extra galaxies in the image, one at 1 o'clock and the other just past 5 o'clock(6 o'clock on the overall image). As for the vignetting, I used to get that when I used a focal reducer with my telescope, not sure why you are getting it though.

Single 10sec shot, 5DC with 100mm f/2

Haven't had the chance to take the mkIII out shooting stars yet, I can't wait to try it though.

IMAGE LINK: http://www.flickr.com/​photos/tomfuller/82721​59821/

IMAGE LINK: http://www.flickr.com/​photos/tomfuller/82732​25110/

04yellowf150 wrote in post #15516519
Here is the big image. I see that 1 distant galaxy but according to stellarium it was the NGC 2976 galaxy. I do not know why there is a circle where its lighter, any tips on that? I dont know if its my processing or if its glare from the moon hitting the telescope tube??

NGC2976 is the one upper centre of your wide image, but that one wasn't in your crop. The one I pointed out in your first image is at 5 o'clock from M81, and that is NGC3077.

The vignetting is what you get when you stretch the contrast. It's caused by natural vignetting of the lens. The best way to get rid of it is to incorporate some "flats" in your stacking. So far I've not done that either, and I end up trying to process it out, and crop the worst bits out of the image.

Madweasel wrote in post #15516849
NGC2976 is the one upper centre of your wide image, but that one wasn't in your crop. The one I pointed out in your first image is at 5 o'clock from M81, and that is NGC3077.

The vignetting is what you get when you stretch the contrast. It's caused by natural vignetting of the lens. The best way to get rid of it is to incorporate some "flats" in your stacking. So far I've not done that either, and I end up trying to process it out, and crop the worst bits out of the image.

Ditto.