The Double Cluster
Oct 11, 2015 03:13:44 #
Here is a look at the Double Cluster. You can find it directly beneath Cassiopeia.
There are a lot of stars in this portion of the sky. This was taken on a crop sensor camera using a 70 - 200mm lens at 200mm @ F2.8 and ISO 1250.
The first shot is a 5 sec shot I had gotten when I was testing my position since the clusters are too dim to see without the camera. (Wikipedia says that the clusters can be seen with the naked eye - not in my backyard!).
The second is a 30 sec shot. At 30 sec, there are so many stars captured, that the clusters almost blend into the sea of stars.
I have added a 13 sec shot. In this one, there were some really thin wispy clouds that were going over as I shot it, and they are impacting the image a bit. This shot is not processed in DxO Optics Pro like the first two, and it is not bringing out as many stars.
I might add that focus was extremely critical for images like these. I had turned on the focus magnifier to it's highest power and ever so carefully adjusted the focus so that star diameters became the absolute smallest I could get. The focus point was so critical that just touching the focus ring could know it off of this critical focus. With F2.8, I could pick a number of stars to focus on, and I picked a dim one as it is the most revealing of the critical focus point. The dim stars actually disappear outside of the focus point. The bright ones tend to get fatter. With a dim star, you focus for the star to become its brightest.
There are a lot of stars in this portion of the sky. This was taken on a crop sensor camera using a 70 - 200mm lens at 200mm @ F2.8 and ISO 1250.
The first shot is a 5 sec shot I had gotten when I was testing my position since the clusters are too dim to see without the camera. (Wikipedia says that the clusters can be seen with the naked eye - not in my backyard!).
The second is a 30 sec shot. At 30 sec, there are so many stars captured, that the clusters almost blend into the sea of stars.
I have added a 13 sec shot. In this one, there were some really thin wispy clouds that were going over as I shot it, and they are impacting the image a bit. This shot is not processed in DxO Optics Pro like the first two, and it is not bringing out as many stars.
I might add that focus was extremely critical for images like these. I had turned on the focus magnifier to it's highest power and ever so carefully adjusted the focus so that star diameters became the absolute smallest I could get. The focus point was so critical that just touching the focus ring could know it off of this critical focus. With F2.8, I could pick a number of stars to focus on, and I picked a dim one as it is the most revealing of the critical focus point. The dim stars actually disappear outside of the focus point. The bright ones tend to get fatter. With a dim star, you focus for the star to become its brightest.
Double Cluster, 5 sec
(Download)
Double Cluster, 30 sec
(Download)
Adding a 13 sec shot
(Download)
13 sec shot - NIK Viveza 2 to the rescue - removed effect of the cloud
(Download)
Oct 11, 2015 03:16:08 #
Oct 11, 2015 03:26:16 #
Nikonian72 wrote:
Thank you, Douglass. I almost think that 30-sec was too long, since it picks up so many stars that the double cluster is almost lost.Your second image is most impressive. :thumbup:
Oct 11, 2015 16:53:43 #
Nice job of PP Jim H. I really want that Lens to fill my inventory of Tamrons.
Oct 11, 2015 17:31:55 #
CraigFair wrote:
I really like them. I have two: the 24-70 f2.8 and the 70-200 f2.8. I can't find fault with them. But they are heavy!Nice job of PP Jim H. I really want that Lens to fill my inventory of Tamrons.
I use them as much on my full frame camera as I do on the crop sensor cameras. They work great on both.
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