It's been clear and dry all week, except for the evenings when there is a thick haze....until last night!
I have had the telescope outside the whole time, just taking in the electronics (cameras, hand controller). The telescope has been set up on the three drilled 'dimples' and then left, having been calibrated, so it didn't take long to get it ready to image. Oh what it must be like to have the mount on a pedestal so its always ready to go!
However, haste waits for the unwary.
Because the moon is just past full and low in the SE, I decided to go for the Owl Cluster, NGC 457 (also known as ET, for obvious reasons). Scope was calibrated really quickly, focused (uh oh) and after centring the Owl Cluster in the guiding camera screen (uh oh), I set it to take 30 x 150 s exposures. It was tracking nicely, so I waited expectantly....
When I looked at the first image (reviewing them, an hour or so later), at first I wondered why my vision seemed blurred..... SO THAT'S THE REASON WE TAKE THE BAHTINOV MASK OFF AFTER FOCUSSING.....
Now, this could have been a good time to notice what the FOV actually was, but no, festina lente ..
An hour or so later, I remembered that when I had centred NGC 457 so carefully in the guide scope FOV, I hadn't checked the telescope FOV to see how they compared. Anyway, here is my 'half and owl' . At least I got the eyes! (top left and upside down, the eyes are the two brightest stars).
I have had the telescope outside the whole time, just taking in the electronics (cameras, hand controller). The telescope has been set up on the three drilled 'dimples' and then left, having been calibrated, so it didn't take long to get it ready to image. Oh what it must be like to have the mount on a pedestal so its always ready to go!
However, haste waits for the unwary.
Because the moon is just past full and low in the SE, I decided to go for the Owl Cluster, NGC 457 (also known as ET, for obvious reasons). Scope was calibrated really quickly, focused (uh oh) and after centring the Owl Cluster in the guiding camera screen (uh oh), I set it to take 30 x 150 s exposures. It was tracking nicely, so I waited expectantly....
When I looked at the first image (reviewing them, an hour or so later), at first I wondered why my vision seemed blurred..... SO THAT'S THE REASON WE TAKE THE BAHTINOV MASK OFF AFTER FOCUSSING.....
Now, this could have been a good time to notice what the FOV actually was, but no, festina lente ..
An hour or so later, I remembered that when I had centred NGC 457 so carefully in the guide scope FOV, I hadn't checked the telescope FOV to see how they compared. Anyway, here is my 'half and owl' . At least I got the eyes! (top left and upside down, the eyes are the two brightest stars).
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