Last night I was up again on my own time, to try to get some images to improve a time lapse sequence I took some 3 years ago - nearly my first one. You can click on the image to the left here to see it. Mistakes were made, and I've learned a lot in doing these over the years. The problem is that if I want to catch the Pleiades rising over the working VLBA radio dish in the foreground, it would have to be this week before the moon gets too bright. By next dark-of-the-moon, the star cluster would already be above the horizon at twilight.
After some car issues, I got up there just before sunset and rushed to get set up. But there are still issues - as twilight faded and I was adjusting exposures, the effect of the 5-day-old moon was greater than I expected. Also, about 30 minutes into the sequence, the radio dish stowed itself and didn't move the rest of the night. It will make for a dull video, I suspect. But having the moon provide some ambient light was a plus, and I continued this one long enough to also catch the Hyades cluster. Other changes included shooting shorter exposures (faster lens) at a quicker clip to reduce star trailing and jumps between frames, but I also used a longer focus lens, so star trails are still there. And I also used another camera with a telephoto to catch some other "events", so edited in, it may add some interest.
This last wide frame at left shows how the Pleiades and Hyades cluster barely fit in the field as they rise into the sky over the 80 foot dish. The view thru the telephoto shows the Pleiades rising over the secondary mirror of the radio telescope - unfortunately, the dish was so close, the stars are slightly out of focus - but the slightly fuzzy stars better show off their subtle colors. Interestingly, even in the 12 second exposures (at F/2.8), the slight glow of the cluster's nebulosity can be spotted to it's lower right!
And finally, taking a sequence of similarly short exposures of the big domes on the peak with the telephoto, I inadvertently captured a trio of star clusters rising past the 4-meter dome. At left here are the domes of the 4-meter Mayall Telescope to the left and Steward Observatory's 90" Bok Telescope to the right. The two fuzzy patches to the left of the big dome are M-36 (below) and M-38 (upper left), and to the upper right of the dome is NGC 1893. The coming Fall and Winter observing seasons features lots of clusters like these.
Oh, and the original gif that inspired all the above is shown here. Note that gifs have limitations in number of colors, so they can appear a little noisy, so forgive me - I'm trying to do better!
So I got some interesting still shots - you'll see it here first if anything interesting shows up in the time-lapse sequence...
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