Monday, June 15, 2020

tried imaging, viewed doubles (Bradford)

Quick report: will be replaced with detailed log entry later...

Viewed some double stars from Sissy Haas's book.

Performed a drift alignment with SkyTools and the Celestron Micro Guide. I saw the pointing was off about 2 degrees and slow drift in photos. But I might have over corrected... But I also totally forgot to redo the star alignment after the new polar alignment. Crikey! 

Tried to image NGC 6520.

Bad seeing again.

Had a big glitch with SkyTools. It froze and I had to reboot the computer. Static? Jostled cable?

§

Mid-day, I headed out back. Found the inside of the tent, according to the Oregon weather station, 40.5 degrees when I opened it! North door, east door, rolled back the observatory fly, cracked the top screen and flap to blow out hot air.

1:19 PM, Sunday 14 June 2020. Rhonda visited, said she really enjoyed seeing Jupiter last night. She was glad she had been able to stay awake. Thought I could work on a better observing plan for rho.

1:22 PM. Another beautiful day. The hot air was exiting the tent. The portable weather unit now showed 30.7°C. It was hard to read the dirty computer screen in the sunlight. Made a note to clean it.

1:37. Brought my bucket of bungees out. Finished off my coffee. Commenced searching for my small carabiners, so to easily secure and release the outer fly. Found two new unused ones in camera bag. But I couldn't remember where the others were, hadn't seen them in recent memory. Finally found them, surprise, surprise in the outboard pocket of the (new) tent bag! I'd still like some S-Biners like what Nite Ize offers.

Sunlight pouring in the west window made it a bit difficult to see. And it was getting warm. 

2:55. Put the Black Cloak of Dome up, outside the tent, with some clips. Nice. Too bad the tent window didn't work the other way. If the flap and zipper were inverted, then you could block out light more effectively. Doesn't work bottom-up. The overall design of this tent is pretty amazing all things considered but that window is a weak link.

Back inside, fired up SkyTools 3 Pro on John Max and activated red mode so to darken things on the desktop computer.

Did some research for Rhonda. M13 or Messier 13 has 300 000 stars. Its radius is about 73 light-years. I tried to research the density of stars in our neighbourhood and inferred the numbers. Learned that in the core of a globular, many stars are about 1 ly apart! Wow.

Made a note to do sewing! I wanted to have the fabric cover done for my custom dew heater report.

§

8:49. Returned to the tent after (my) dinner, after checking in on Rhonda, watering her, feeding Tucker, taking the laundry down.

Stumbled across three DEET bottles in "summer season" bag. Can you have too much? Decided to burn a coil tonight. Easily done with the matches in the bag, woo.

Worked on some double stars for the observing list. Nothing too difficult, so fairly bright, maybe around 30 or 40 arc-seconds. Consulted Haas's book and my lists. Spotted some typos and errors in my double star life list pages. Considered what made for pleasing views in the small 'scope, good splits in the ETX 90mm. I found some telling entries:
  • 36.7": nearly equal stars, quite wide at 48x but attractive
  • mind you, I made it to 2.2" with the Meade MCT
  • 20.9": on the AL binocular list, wide pair at 48 power, nice but faint
  • 11.3": tack sharp, good seeing, a tight double, nearly equal
Perhaps the sweet spot was 10 to 20 seconds of arc. Added about two per well-spaced constellation. Good stuff.

10:04. Finished two-star alignment. Better numbers than yesterday but still off by about one arc-minute on one axis.

Rhonda arrived looking like she was heading out for a winter excursion. With traveller. We talked about aloo gobi. Mmm. I should learn how to make that.

Showed her the red LED string control box and had her push the mode button. 

I used the Celestron Micro Guide. Hit the limit on in-focus so just went ahead with the defocused diffraction pattern. [ed: Totally forgetting, at the time, to move the mirror for focusing, duh.] Later showed Rhonda the rings upon rings. Like ripples on water. She noted it wavering and shimmering—that was the air seeing amplified.

Even through I was pretty close to the pole, I wanted better pointing and less drift. Started the drift alignment process with SkyTools 3 Professional in Real-Time mode. The app immediately slewed and I could see some stars. I wondered which was the target but then realised it didn't really matter. Choose anything nearby. Checked both axis (after disconnecting and reconnecting). 

Carried on observing. [ed: Totally forgot to restart the mount! DOH! This meant I was not, in fact, taking advantage of the drift alignment corrections all night! Ha.]

10:35. Told rho I had looked up some interesting double stars. From double stars for small telescopes.

Tried the sync command again. No joy. Oh well. Carry on.

Chose HR 5568. A long slew started... on the other side of the meridian. I didn't want to flip. 

Chose a target in Serpens Caput, a mag 7 star, but I didn't know where I was—HD 142930. Used a bright star to get my bearings and located the double. Faint. "Oh. Nice one." A tight pair. Shared the view. Rhonda said they were fuzzy. And drifting to the left. Huh? It was way off. I re-centred. Found the sidereal tracking was off; turned it back on. Did the computer do that? Or me? Faint for sure but great colours, yellow and orange. Same brightnesses. 

She thought the one on the right was warmer, citrus-y, top one was blue-y, white, cold-white. The brightest one on the left was blue. Hold on. She was mistaking a wide field star for the partner. Let's reset. Tight pair, top orange, bottom brighter, "twice as bright" she said. I estimated one magnitude.

I looked again. Upper one orange, for sure. 

Increased the power. Talked about eyepiece design and that they should be neutral. Colour of doubles was mostly human perception. Too close and the colours blended; too far and the viewer is not left with strong impressions. There was a sweet spot. And you can't have green!

We didn't think they were so colourful. Not good seeing, again. Thought I saw something... Software freaked out. Was this the static problem that I had seen before?

We chatted about names, things reopening, aching muscles, frost warnings, local building supply stores, while I rebooted the computer. Heard animals quietly moving around in the yard. Warned about stepping on or pulling cables. Rhonda remembered me having red lights in the tent...

11:05. Whoa. I spotted another pair! Extremely faint. Averted. Left. Two in the view! Thought I saw something to the north as well... No colours. PPM 162075. At a different angle to the first pair.

I noticed Antares. That got me thinking about my imaging target. Rhonda went to make some tea.

11:15. Slewed to Antares to get in the 'hood and to help focus. Crazy-low candidate. Time for more wires! Got out all the camera gear: 40D (with kit lens installed), USB cable, bayonet t-ring, t-adapter, body cap, lens back cap, DC coupler, power supply, and power cable. Grabbed a cap for the mirror diagonal. Had to take out the red keyboard light to free up a USB port. Mounted the camera. Connected to the computer, extinguished EOS Utility, and launched Backyard EOS. 

When rho returned I showed her a shimmering out-of-focus Antares, bad seeing in action. Looked like a light on a cop car.

I focused using the HFD (half-flux diameter) method (having heard it was better or more robust in bad seeing). 7.0, 6.9. I think I saw some drift, grrr. [ed: Dumbass.]

Rhonda asked about Jupiter events tonight. Yes, there was another shadow transit, by Europa this time, and the Great Red Spot, but around 2 o'clock.

11:46. Slewed to a bright star. Planned a test exposure at 5 seconds, high ISO 1600, verified RAW, two shots. Round stars. OK. Up to 10 seconds. Still round! I was surprised given I had not aligned on Polaris nor performed a drift alignment routine.

Just remembered that I had "fixed" my weather centre input for BYE. Wondered where the file was. I scanned the desktop but didn't see it. [ed: It was there.] Did a Windows search and finally found it, a file called my_wx.txt in the D drive, astronomy folder, and the BYE photos sub.

Not a lot of mosquitoes. We checked if the coil was still burning. Nope, done. Got out another coil.

Rhonda called it an evening. A school night and all.

12:00 AM, Monday 15 June 2020. Checked the conditions: 45% humidity, 11.5°.

All photos ISO 1600, daylight white balance, RAW format of course. No edits applied, no dark subtraction, and so on.

12:07. Imaged HD 145876 in Ophiuchus, very near Yed Prior or the bright δ (delta) star. It's near the top-right of the image. North is up, east is left. Bumped from 10 seconds to 20.

stars with HD 145876

Considered getting the weather info from the web. Ugh, too awkward on the old Windows box. 

12:10 AM. Took the weather data from the smartphone and set the temperature and humidity. 10 degrees, 61 percent. It rolled into BYE after a few seconds.

It seemed I had some time to kill so I thought I could try to capture some interesting doubles.

Continued shooting.

12:13. Imaged θ (theta) Ophiuchi. In the first two images, the drive hadn't settled so there's was some significant drift. Gear slop. Blue-white star with orange HD 156992 to the north-west. [ed: nova.astrometry.net could not plate-solve this but I figured it out.]

blue-white theta Ophiuchi

Switched to camera mode in SkyTools. Discovered I was in general or "simple" mode in SkyTools and that's what was blocking some items earlier. Switched to photography mode. NGC 6520 was included again.

[ed: Those nearby stars are not officially part of the double that is CHR 182 where the B partner is a mere 0.3" away.]

Disconnected, reconnected, slewed, panned.

Continued shooting.

Panned.

Continued shooting.

It looked like the open cluster would be clearing the trees soon... Cold. Headed inside for clothing. Returned. 

Continued shooting.

I couldn't figure it out the field...

12:31. I still had to wait for the target to clear the trees. Closed the window facing west.

Disconnected, connected, slewed a short distance, centred.

Continued shooting. Chuckled at the result. Tight, unequal double.

12:36. Imaged double HR 6681 in Serpens, aka HJ 2814, a suggestion from Haas's book. Tried 15 and 20 seconds exposures. [ed: Plate-solved in nova.astrometry.net as HD 163336.]

double HR 6681

North is up, east is left. Blue-white primary and a grey dim secondary to the south. Great pair. [ed: That's the B star. The HJ double actually has three stars. The C is opposite B, 2 or 3 times the distance. It is extremely dim.]

Disconnected, connected, slewed a short distance, centred.

Took a single shot.

Panned again, using the finder scope.

Took a shot.

Disconnected, connected, slewed a very short distance, centred.

Disconnected, connected, slewed a long distance.

Disconnected, connected, slewed in both axes, centred.

Took a single shot. 20 seconds.

Took another shot. 10 seconds.

Disconnected, connected, slewed a very short distance, panned.

Disconnected, connected, slewed a very short distance.

This was gonna be tough without good pointing. [ed: Silly rabbit.]

Disconnected, connected, slewed a long way. Into Sagittarius. Time to get serious.

It should have been in the open now, in the notch between the trees.

1:02. Moved the TV table.

Panned around a bit.

Took a shot.

Panned.

Took two single shots. Fire truck! Drifting.

Shot again.

1:06. Tried to manually identify the field in Sagittarius. I finally figured it out! Imaged HR 6766 at 20 seconds, north is up, east is left. [ed: Plate-solved again, with the bright star IDed as HD 165634. A little over 1 degree south-east of the cluster!]

Disconnected, connected, made a very tiny slew. 

Shot again.

I was a little west of the previous position, a touch north. But needed to go further... The window of opportunity was closing as the target moved inexorably toward the thick deciduous tree. 

Tried to gauge the pointing offset.

Disconnected, connected. Did another tiny slew.

Shot.

The image was being darkened by the tree! "Come on." I was feeling pressure, running out of time.

Disconnected, connected. Did another tiny slew. 

Nope. Still not on the cluster.

Scuppered! Ran out of time. Gah. I had been so close! 

Tore down the camera gear and reinstalled an eyepiece.

Disconnected, connected, slewed, panned.

Returned to HR 6681 in Serpens Cauda.

1:24. Up (north) and down for me. Very nice at low power. Easy split. Yellow and orange. A and B were no problem. I did not see an obvious C star. The seeing was really bad. Loaded a more powerful eyepiece. C? Maybe with averted. Twice the distance?

Switched back to eyepiece/visual mode in ST3P.

Spotted a faint colourless double to the south, with averted vision. The software said this was ARA 7. Same orientation.

The planning app was showing too many stars. Adjusted the light pollution, temperature, and humidity settings which helped.

There was a little triangle of stars to my left (actually south-west) with GSC 6250-226 at magnitude 11.4 and GSC 6250-612 at mag 12.6. I took in many other faint field stars. Curious, the C star was mag 11.5 so should have been possible.

1:30. Spotted Jupiter and Saturn through the tree.

Considered my next target on the same side of the meridian. Chose an object in Lyra.

Small airplane flew overhead while I centred.

1:45. Viewed HR 7033, aka STF 2372, an entry from Sissy's book. Wide pair with the low power eyepiece. Yellow and blue. Yes! I also got the faint C star to the east. Score! [ed: Mag 11.4.] I did not attempt the P star at 0.1".

Saw a small ring of five stars that reminded me of Auriga. Lovely field.

Noticed a triangle nearby. Triple. Below. To the east. Super-faint. Really faint. One of the apices harboured a double: SEI 572.

Out at the edge of the field I saw another faint pair, aiming toward HR 7033. That was SEI 573. The eastern star was brighter.

OK, next?

Disconnected, connected, big slew. Whole lot of nothing. Once again, lost.

Reconnected again, slewed, centred.

Disconnected, connected, slewed.

Disconnected, connected, slewed, panned.

Tried the sync command again in SkyTools.

Connected. Slewed. Struggled. Panned.

2:11. Finally made it! To the east. Triad. A and B were obvious. Bright star was yellow. Yellow and blue? Nearly equal brightness. West star was very slightly dimmer. Oriented nearly perfectly east-west. B slightly to the north. [ed: Grrr. I did not note the name. Is this HD 150340?]

[ed: OK. A triad of faint stars to the east, a triangle way off to the west (low power), stars similar magnitudes with a delta of 1, west star is dimmer, nearly EW with B a bit to the north, marked as Observed, one of a dozen entries not processed, from a short list of 3 candidates. Sounds like HR 8101 aka STF 2769. ST3P says mag 6.7 and 7.6, PA 299, sep 17.9", in Vulpecula, down low. From my double star programme, v3. Is it good? I thought so.]

A little triangle way off to the west.

Headed to Pallas, asteroid number 2, near Collinder 399. Spotted double HD 182570, really tight, yellow and blue. I did not see the third companion. That struck a cord. I had seen it yesterday...

I wanted to see the little rock in the software so I turn on the minor planet display. Then I turned on the minor planet option for the supplemental database. Oh oh... It started slogging. I was worried I had locked it up. Rolled back. Whew. I continued to struggle with the software. And snap! That's it. I couldn't take it anymore.

Packed up.

2:36. Exited. Unrolled the fly, installed some carabiners. Zipped up. Headed back to the house.

2:42. Back inside.

§

Oh. I suddenly remembered that I was missing some red light in the tent. I didn't have a spare string of red Xmas lights any more, they were all used up inside. Previously I had put a string in the arch of the tent which made it easier to see. That's what Rhonda was referring to...

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