Tuesday, February 15, 2011

bad seeing (Toronto)

I wasn't expecting a lot. Still, I thought I'd meet with a bit more success. It proved to be a bit frustrating this session. Atmospheric conditions? High wind (er, high winds high up)? My eyes? Observing over hot rooftops and chimneys? All of the above?

12:24 AM. I tried my hand-made Bahtinov focus-mask. One word: amazing! It's true. It is outstanding. Unmistakable. I'm a convert. I'm a disciple. It makes it so easy to focus! There is no doubt now when focusing. This will be so useful for photography.

Now, all that said, it's a bit of a hassle with the dew shield installed. I had to flex the disk and wriggle it down the shield. It is partly because the plastic shield is tapered at the front. It is also slightly tighter on the inside now that I've installed the flock paper.

I wonder if it might be easier to do focusing first, before you've installed the dew shield. Will need to noodle on this a bit. If a focus change is required more than once in a session, it will be fiddly. Perhaps this is an advantage to "draping" the mask on the front of the 'scope. Huh. I could try it in front of the dew shield...

Regardless, it was astonishingly easy to focus.

OK. Official observing time now!

Looked through the large gap in the trees to the west. Orion was setting, Sirius was just above the treeline. Monoceros should be above. SkyTools3 suggested double star J 717 A. I tried starhopping from Sirius via β (beta) Mon but couldn't do it in time. Struggled a bit with the ST3 software; refused to use Stellarium to help. Damn faint stars in The Unicorn. In the end, it was too low a target. OK. Something high up then!

I'm still really struggling with how ST3 presents the "telescope" 3 panel view. This is probably the view I should use when starhopping but, tonight, for me, it is useless. It is not showing nearly the number of stars I need. I abandoned it and just worked with the Interactive Atlas and Context Viewer windows.

I heard a different note from the mount motor. Normally, when the clutch is disengaged, there is a light chatter from the motor. When it is under load, the chatter goes away, leaving only a whir or soft electric grind sound. Now it was making a chattering noise all the time. It made me think, at first, that the clutch was not tight. It was engaged. I wondered if it was increased loading due to the cold temperature. Made me wonder at the condition of the grease in the old beast. Maybe I should freshen it up...

1:37. I tried to split SAO 16732, aka Σ3125, in Ursa Minor, off the bottom edge of the pot. Successfully starhopped to the target starting at γ (gamma) UMi. ST3 showed a gaggle of stars, along the route, around RA 15 14 39, dec +68 21 28, but I didn't see anything. I also saw the wide double Σ1958 nearby (mag 9.58 and 10.3 stars about 29.6" apart). But I could not split 3125. ST3 said they were mag 10.31 and 10.3 and 2.1" apart. Ooh. Tight. I tried the baader planetarium 36mm, Celestron 26mm, and Tele Vue 9mm eyepieces (56x, 77x, and +200x respectively) without luck.

1:47. Viewed Saturn. It was delicious in the baader Hyperion-Aspherical ocular with its wide field. The planet was very bright. Cloud bands could be easily seen. The northern region seemed a homogeneous tan. Couldn't pick off any variations.

Noted a medium bright point just over 1 ring-width to the right, a very faint point less than 1 rw on the left, and a very bright point further left. ST3 informed me they were Rhea (east), Dione, and Titan (west). A couple of bright stars below.

Dione came and went. As the seeing changed, I'd lose sight of the mag 10.5 moon. It was easy to spot with the Tele Vue Nagler Type 6.

My feet were a little sore. I wanted to sit at the eyepiece. I hadn't done so with any of the targets so far (expect when working with Polaris). It was a tight fit, given the spot I had selected for the the tripod, beside the BBQ and the tripod. I had to wriggle up to the mount and then pull the chair in behind me. But it proved futile. Kept touching the tripod with my left leg. The chair was very slippy with ski pants. So I kept sliding forward.

That reminded me that I never got round to the adding the sawdust layer to the seat! Damn. Shoulda done it as soon as I collected the stuff from the CAO last summer! Now I had no idea where the Spar Varish was... Loser.

My feet were bothering me. I needed a place to sit. Ideally, a chair at the kitchen table would have been perfect. When I clear it of renovation bits and tools, it will be great for this. I pulled a lawn chair into the kitchen and plopped down. Aah. Warmed up a light as I played with ST3.

Kept returning to Saturn. It wasn't a great view. It was almost impossible to see the Cassini Division. I tried and tried to tag Enceladus and Tethys on the right side of the rings. The 222 magnification was a little soft.

2:49. I split HD 129600 aka Σ1871 in Boötes. But it was not easy. Yes, it was another tight double at 2" separation but probably accomplished due to their brightness. I thought them equal brightness and a bluish colour, both, similar. ST3 said the mags were 7.26 and 8.16.

I wondered if the conditions were off. Was the seeing poor?

And then the Velcro end on the eyepiece heater strap broke off. Damn. It finally went.

Took another look at Saturn and then threw in towel.

And, finally, did my "quick" shutdown. Removed all the wires and tossed them in a chair. Dismounted the OTA and laid it in the kitchen. Removed the mount and laid it in the kitchen. Brought the tripod, intact, extended from the porch. Did not knock anything over. Done.

Thought briefly about leaving the 'scope outside at ambient temperature to again speed future use.

Trundled to bed.


Only 5 objects were viewed for the evening, including Polaris. Huh. Not a lot.

The view of Saturn was a little murky.

The focus-mask testing proved the highlight of the evening!

Oh. And the tracking was bang on. Despite the burden on the motor. That was pretty cool.

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