Saturday, July 05, 2014

conducted many experiments (Blue Mountains)

Ian W, supervisor, arrived in the early afternoon. Proceeded to set up his big custom Dobsonian.

9:25 PM, Friday 4 July 2014. It was warmer tonight. And the mosquitoes were out!

Looked at Jupiter. It was barely detectable.

9:43 PM. Viewed Saturn and Titan.

10:04. Tony and I chatted about the upcoming painting. He suggested a water-based acrylic.

10:14. Viewed ν (nu) Sco.

10:22. Ian thought he could see the AB split. Not me. I could not cleanly split them. But it was certainly not round. Damn, he's got good eyes. C and D were split by a hair. A and B were a pale yellow. C and D much dimmer, very pale blue, maybe. Neat field stars, HD 145554 and HD 145631, near by. Bright.

We thought the C14 collimation off a bit.

10:48. Ian and I tried to split ζ (zeta) Her. No luck in the C14 or his 20-inch. Interesting...

I wanted to do some imaging "experiments" tonight. First, some double stars.

Headed off to 59 Serpentis. It is listed in the RASC coloured doubles. They describe it as yellow and green! SkyTools 3 Professional notes it as a triple but the AP pair has a separation of 0.3 arc-seconds. Yikes. The AB sep on the other hand is reasonable: 3.9.

12:47 AM, Saturday 5 July 2014. Finished imaging the double star 59 Ser (the light frames). Started taking 10 darks. I wondered if I had discovered something interesting in these images... Something in the area. It didn't look like I split the A and B stars in the images. Overexposed perhaps.

[ed: Image shown in a different post.]

1:02 AM. Finished the darks gathering.

Headed to the Observing Pad. Now I wanted to try out Risa's iOptron tracking device.

1:23 AM. Downloaded the SkyTracker manual. Started working through the steps. I wanted to do it all completely on my own. A little challenging but I figured it out. I'd rewritten the manual...

Did some wide-field Milky Way stuff. Was trying to capture comet Catalina.

Just as my run finished I swung to the north-west and imaged the Iridium flare! Neat.

Headed back to the observatory. Using Ian's hefty dovetail camera bracket, I attached the Canon DSLR to the C14 tube for some piggyback imaging. Another experiment.

3:59. Tried to image NGC 6946, the Fireworks Galaxy, with my old, big, heavy, Vivitar Series 1 lens. First time ever doing astrophotography, made possible by the Fotodiox M42 adapter. The sky was brightening...

4:02. Checked the weather conditions. Wind 4.8, high 14.5, 10 min 4.8, from the west, temp 13.7, hum 66, baro 1023.1.

4:23. Did darks. Closed the roof. Put the dehumidifier on.

4:32. As I walked to the house, I saw Venus rising. I also spotted a star to the right. Ah. Aldebaran.

4:36. In bed.

Unwound. The night had been a bit scattered but I had a good amount of fun trying things.

For a long time I have wanted to test and evaluate my old camera lenses. I loved using the 70-210mm Series 1 zoom lens with the old Pentax film bodies. I'm really curious if it can render good images at night. I also have the fixed 100mm portrait lens by Vivitar. It might be good. And I have one fast wide field. Tonight, I finally put the zoom on. But it was a half-baked test.

I think the better thing to do is a dedicated evening, that is, try each lens, one after the other, shoot many images of different subjects. That'd mean less fiddling with dismounting the refractor, etc. Do it all in one evening. "Old lens test night!"

I'm also betwixt with these tracking devices. The SkyTracker, the Polarie, the new Star Adventurer. All are tantalising. I don't know why but it is so tempting to get one. Yes, they are expensive. And I suspected they would be non-trivial to set up. And I was also really curious how good one's polar alignment would need to be.

It was really interesting working with Risa's iOptron, very educational. It was not trivial to set up. I was cognisant of the time. It's not a couple of minutes. It's maybe a good 30 minutes, once you have it down, to do it right. Which, intriguingly, is about the time it takes to set up the old Vixen Super Polaris. Yep. I keep coming back to that.

It'd be silly, I think, to get a tracking device, when I already have a "lightweight" equatorial mount. The Vixen SP should be able to do an excellent job of tracking underneath the DSLR. It can even run on batteries (or could)! So that's the crux of the matter. That's what I should be testing. I'm getting distracted by gadgets!

A good evening.

One more dark. Yeh.

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