some success last night regarding the focus issue.
There were relatively clear skies, and I took the camera out. I got some test shots, showing the focus at 24 mm was acceptable, when done right.
Moreover, I discovered a technique. Using live view, I can expand the image to include one star and actually do a decent job of focusing on that when it is magnified. So I won't have to rely on shining a light on my focus ring, or having to have a table of proper focus points for each setting of the focal length.
However, the stars are oval.. Coma? It appears I did this at 85 mm. May want to try at 24. May be different.
Nice disk, overexposed by a lot. Would be interesting to see what I could do with the 300 mm.
Exposure here was ISO 2500, 85 mm, f/4.5, 1.o0 sec
Now, on to learning how to get a set of images to stack.
What ISO to use, what exposure to use?
And, time lapse movies. That would be good.
I think I will ask cloudy nights on this one.
It was interesting that a number of the overexposed frames had a reddish cast to the background. I do not understand. Some of the other frames, including some ground lights, had a slight bluish cast. I conclude that the reddish cast was the white balance. May need to attend to that. Especially going to get the Aurora. Wouldn't want that to be off.
There were relatively clear skies, and I took the camera out. I got some test shots, showing the focus at 24 mm was acceptable, when done right.
Moreover, I discovered a technique. Using live view, I can expand the image to include one star and actually do a decent job of focusing on that when it is magnified. So I won't have to rely on shining a light on my focus ring, or having to have a table of proper focus points for each setting of the focal length.
However, the stars are oval.. Coma? It appears I did this at 85 mm. May want to try at 24. May be different.
here is an image of Mars taken at 85 mm.
Nice disk, overexposed by a lot. Would be interesting to see what I could do with the 300 mm.
Exposure here was ISO 2500, 85 mm, f/4.5, 1.o0 sec
Now, on to learning how to get a set of images to stack.
What ISO to use, what exposure to use?
And, time lapse movies. That would be good.
I think I will ask cloudy nights on this one.
It was interesting that a number of the overexposed frames had a reddish cast to the background. I do not understand. Some of the other frames, including some ground lights, had a slight bluish cast. I conclude that the reddish cast was the white balance. May need to attend to that. Especially going to get the Aurora. Wouldn't want that to be off.
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