Saturday, September 23, 2017

helped member image

Geneviève was interesting in imaging through the C14 with her DSLR camera. Earlier in the month we had discussed using the equipment in the Geoff Brown Observatory (and at the time I was not to be supervising). I said then if it was OK with the supervisor, I was OK to help. Now that I was the supervisor, I told her we were OK to proceed as long as no one else had booked telescope time. There were no takers. That said, I did have a few things I wanted to look at. And I wanted to show Rhonda some favourite DSOs.

9:05 PM, Friday 22 September 2017. Geneviève brought her gear into the warm room. She had a list of targets. Dumbbell, NGC 6826 aka Blinking planetary nebula, Orion Nebula. We checked locations and simulated views in SkyTools. Checked the elevation and meridian. Did Google search. Dumbbell was good, near Cygnus, high, it was just crossing the meridian. The Blinking was in Cygnus but small. Very small. We simulated the framing with a 2x doubler (mine) and 4x (RASC's). We looked at images from Burke-Gaffney and Hubble. Dumbbell was it.

We talked about computers as she's shopping for a new one. At first she was thinking about Surface Pro. The associate at a store gave her many suggestions including ASUS. Discussed her personal and work needs. I wondered if I would have to go with a gamer style portable computer in the future for fast response with my work apps along with modern connections and the ability to do some medium to light-advanced image processing on the road. Alienware computers would be a good option but they are very expensive.

Told Geneviève my preference for "working:" sitting in the warm room (on this occasion, away from the bugs), capturing images on one computer, and focusing remotely with another. Asked if she had the Canon software on her computer. She headed to the house.

9:37 PM. She returned with computer.

She did not have proper red film; she used two small sheets of red plastic overlapped.

Geneviève showed me a couple of software CDs (the camera instruction manual and the software instruction manual) but they didn't sound right. That's all she had. She shared she had the EOS Utility installed from her old camera. I suggested we try it as it might work fine. Connect the camera and let's see what happens.

Accidentally tripped the camera a couple of times, with the flash firing. Lightning in the warm room!

9:55. She got the EOS Utility running. I had Geneviève hit the Live View button. Had her take the lens cap off and move the camera about. It was working fine. We found the button to toggle off the focus region rectangles. I explained we would not need her intervalometer as EU would do that.

Again, I told her that I liked working in the warm room with the two computers and if she wanted to do that, we'd have to hook up things via the subterranean cable and drop another cable. Or she could sit on the observatory floor near the pier and do things on her computer and use the Optec hand paddle. She chose the warm room option. We made space on the south counter.

I offered my 2-inch nose piece as Geneviève only had a 1¼.

We connected my high-speed USB-ethernet adapter kit to the underground cable.

Asked if she had a DC coupler. No. Asked if she had a battery grip. No. Battery charged? Yes. She also had a spare battery. We connected her camera at the pier, fired up EU, activated the Live View, and tested it by shining a light in the lens.

We set up the remote focusing. I plugged in the custom serial-RJ adapter to the RASC computer (as it was not currently connected to the Paramount ME). Dropped the 6-wire into the observatory and connected to the hand paddle. Launched the app on the Dell machine. Didn't work. I wondered if the hand box was in automatic mode. I found it in manual. Weird. Reseated the connector and tried again. It worked. (Forgot to put the focuser in the middle of the range.)

Richard said were about to lose the sky. Hurry. Hurry hard.

Slewed to a bright star, γ (gamma) Sge. Advised Richard to not back up.

We mounted the camera. Took out the mirror diagonal and ocular. Attached the t-ring and t-adapter to the body. Installed the camera in the focuser drawtube. Gently and progressively tightened the three screws. Looped the strap over another 'scope. Tethered the camera to the big OTA. Camera timed out so we powered it back on.

We checked the Live View Shooting. We shifted the apps on her computer screen so she could see the camera control panel with the Live View. The exposure was at 1/1000. Showed her how to change it. The ISO was at 5000 which was fine for now. I explained that Exposure Simulation would only go so far but should still work for us.

10:36. Clouds prevented us from seeing the star. We paused. I took the opportunity to head to the work room to get some duct tape. It was clearing to the north. Yeh.

We taped down the RJ cable to prevent tripping. I would have preferred double-wide. Tony illuminated the scene with his new red flashlight from Amazon.

We focused. We could see a faint, large donut on the screen. I adjusted the focus using the SCT knob, sliding the primary mirror, crudely focusing, focusing coarsely, while Geneviève monitored the computer. I started by turning the control clockwise until we got a small dot. Went back and forth, following her commands, a bit to make the point as small as possible. We transitioned to the electronic focuser.

In EOS Utility, I wanted to zoom in but the button was not active. After trying some controls, I looked up the issue in Google. Learned we had to turn the Face Detection off; went to Quick Mode. We were able to open the zoom window. Then go to 200%. Centred with the arrows or dragging. Noted the seeing conditions.

Explained that we had 7000 ticks to work with on the Optec TCF-S, we were at 1455 now, and we documented that. Talked about the granularity. She liked the view around 600. We changed the granularity to 50 from 100 and she continued adjusting the focuser. She landed at 820. Suggested a test shot so we could zoom in even more. Suggested 10 or 20 seconds. She chose 10. We checked her ISO range: it went up to 12 800. We chose 1000.

Shared that Richard and I used Backyard EOS and it offered a number of tools to aid in focusing including Full Width Half Maximum.

When I restarted SkyTools after a fatal error, I discussed the offset we'd need to use. It was significant on this occasion as the telescope pointing was way off.

I noted that her EU showed the mirror lock setting. Suggested we didn't need it for our long exposures.

Geneviève took a test shot. I suggested the Quick Preview was not useful—we closed it. We saw the Digital Photo Professional launch automatically. We opened the last photo into a large window. We displayed the Tools panel. I said to drag the brightness slider all the way so we could see lots of stars. We compared the camera frame to my SkyTools window and confirmed we were in right area. I didn't need to turn the FOV rectangle. We shot again at 20 seconds. Zoomed in to 100%. Ignored hot pixels. I thought it was very good focus. We turned the Optec software to automatic mode, using the temperature sensor.

11:18. We acquired Messier 27. Or thought we did. We had to guess the offset. I used Slew to Cursor. She took another long exposure. We wondered if it was cloudy. Sailu told us it was clear near Cygnus. We brightened the last shot; we stretched it too. We did some plate solving visually. We stretched the image some more and spotted the nebula on the top edge of the frame. Slewed a bit. Took another shot. It was nearly perfectly centred.

Rhonda visited, met Geneviève, looked in the TV 101, noted the large fuzzy.

We prepared to take long exposures. 30 seconds wasn't enough; I wanted to double the data. I showed the Timer function in EU. We programmed a 1 minute exposure and set the interval a few seconds longer. Left the number of exposures at 10 with the intention of cancelling after the first shot. Ran the timer. It closed the shutter after 30 seconds. It seemed to me the camera was following its exposure time and not using the software setting of 60 seconds. I was looking for the bulb setting in the exposure values given my 40D experience: I moved past 30 seconds and the bulb mode was shown. When I learned that the 70D has a B mode on the dial, I had Geneviève set that on the camera body. Of course, once reflected in the software, it worked. The EU removed the exposure values from the control window which made sense. A slightly different experience than what I am used to.

The fun part now. Hurry up and wait.

We checked the test shot. It did not seem as good to me; it was dim. I asked to check the Info (from the File menu). 18 seconds. Nope. Re-shoot. We were a little confused about the times. I thought it was using a long delay before shooting the first time... The image downloaded. It was a minute exposure. Good colour, good focus, but some trailing. We changed to a 2 minute shot with a 3 minute interval. I looked closely at the timing box. Oh. It was working right! At the start or trigger point, the shutter opened and counted down, as shown at the bottom of the timing box; the countdown timer at the top was for the next shutter activation.

Showed to Sailu and Geneviève my star trace and that the telescope moves. Vibration, wind, periodic errors.

The faster shot was better, less trailing. But I recommended gathering many light frames in case some showed trailing.

11:50. We set up the image capture. One minute exposures, a 15 second gap, 30 shots, no delay. Go! Coffee time. Encouraged her to set an alarm.

12:05 AM, Saturday 23 September 2017. We returned to the GBO.

Checked the weather conditions for the Davis unit on site. The outside air temperature was 20.3°C, the humidity 84%, barometric pressure 1017.0 hPa, 10 minute average wind speed 6.4 km/h, wind direction south. She updated her log notes.

Geneviève noted the focuser value was at 914, up from the starting point.

She asked about another target. I reminded her that we wanted to do some visual observing after this.

We discussed targets good in September. Richard suggest the big globulars like M13 or M92. Too late. And the Owl Cluster. I pointed out that constellations near the zenith at midnight included Lacerta, Cepheus, Cygnus, Pegasus, Andromeda, and Cassiopeia. She asked about the Whale; I thought it out of season.

We showed Richard the stretched frame. He liked it. Pointed out some of the nebulosity.

12:29 AM. Two more shots to go. Her alarm went off.

The imaging run finished.

Prepared for darks. I suggested she remove the camera from the 'scope, install the body plug, and set it beside the pier. Then she could gather 15 or so dark frames. We dismounted the DSLR. I reinstalled the visual equipment.

Geneviève said she had already captured M13, last June.

Showed her The Evening Sky Map document I had downloaded. Suggested it was good for knowing well-placed constellations and telescopic targets from the relevant list. Said she could print it or download the PDF. Cautioned her about low targets. She saw the Whirlpool and the Helix. Yep, interesting. Whirlpool is better in the spring though. She asked about the Saturn Nebula. Small.

We discussed the size of objects. I suggested she Google them, do so research, to determine their size. From SkyTools, we learned that the Dumbbell is 8 arcminutes in size. It almost filled the camera frame. I quickly checked the dimensions in the software. Her camera was about 12 by 19 minutes of arc. The Blinking in contrast is 27", half an arcminute; it would be tiny in the camera.

12:54. I did the SkyTools software pitch. The Nightly Observing Light Generator, using the date and time and location and instrument, is perfect suggesting things to look at or image.

1:07. The dark run was done. Hot pixel data gathered.

We discussed flats (for dust, etc.) and biases (electronic noise). For future consideration. Richard had recently purchased a light pad for tracing, the same type that Steve was using, with very even illumination.

Asked if she could turn her screen brightness down.

She and Richard considered targets. Geneviève referred to the TESM list. She spotted the Trifid. It is big, 28'. Her frame would only get a portion. The Omega aka M17 aka The Swan she thought nice. 11' in size. Magnitude 6. Sets at midnight. An early summer object. Anything in Sagittarius is best viewed in July. The Crescent Nebula, 20 by 10'. Magnitude 7.4, about the same brightness. Transits at 9 PM. The Bode galaxies (e.g. M81) were higher up and brighter than the Crescent (aka The Brain).

1:45. We checked the sizes in SkyTools. The Crescent would require carefully turning the camera body to fit it. M81 was at its lowest point for the year. March and April would be best. The Crescent, right in the middle of The Swan, was very high earlier in the evening. Checked the meridian line. 9:30 would be the perfect time to start. Astro-twilight was an hour or so before that.

Geneviève asked about a galaxy up high. I pulled up the RASC Finest NGC list, filtered on galaxies, above 2x. Found 10 candidates. NGC 891 in Andromeda. I showed my BGO shot from a year ago. Late evening object, 3-ish it peaked, over the 2x at 11. NGC 772 in Aries, another late night target. Faint and kinda small but neat features in it. I reminded them that my images were 60 seconds but from a 24-inch big gun. NGC 185. I imaged it a year ago. Mag 10. Interesting stuff in the core. NGC 936. Small. NGC 6946 or the Fireworks. Mag 9.8. Peaks at 10 PM. NGC 6503. Edge-on. Detail in the arms. I imaged it in May. Very early evening. 7331. With the Fleas? Yes. Super bright core. Nice spiral structure. Good at midnight. NGC 1023. Another Arp, a pair of galaxies. I imaged them a year ago. Faint. We thought some of these suggestions from RASC were nice.

She wondered about imaging several objects, something at 9, 10, 11, midnight. Whoa. Keen. I reminded her we might need to share the 'scope tomorrow. More members coming up. Asked her to prioritise.

Geneviève tore down her camera. Reminded her to take the USB cable proper. Explained that the EOS Utility likely prevented the images from being stored on the camera.

She was keen to stack the images tomorrow.

She headed to bed. Thanked me for the help.

No comments: