Thursday, June 08, 2017

testing framing and spacing (Bradford)

With the clear skies, I wanted to conduct some imaging tests in advance of the solar eclipse. I could use the full Moon for gauging the framing and spacing.

I prepared the equipment needed. Tripod and hex quick-release plate. The DSLR Canon 40D camera body. I decided to try the 18-55 kit zoom lens at 55mm based on Espenak's multiple exposure photo from the 1994 November event. He had used a 50mm Nikkor. I sent the zoom level, turned off the automatic focus, and manually focused to infinity.

Fred had shot the Sun every 5 minutes in his portrait shot. I liked the spacing. So I programmed the intervalometer for 5 minute intervals. I set the exposure length to 15 seconds knowing the camera would override. I set the start delay to 10 seconds.

I installed the battery grip and loaded it with one charged battery. I tested the external power source DC coupler. I grabbed an extension cord.

I considered dew heating. Environment Canada said the evening low temperature would be 7°C with a dew point of 8.6°C (from the 2:20 report). The humidity was standing at 46%. Not bad. Still, I readied the gear: 2-inch wrap on the lens, custom controller, NOCO battery with hacked power leads.

Espenak said he used ISO 100 and f/5.6. I did a bit of searching. One person said to not go slower than 1/125th of a second to avoid motion blur. And then I found details of the Looney 11 rule. Set your f-stop to f/11, then match the shutter speed to your ISO.

I considered matching Fred's old film sensitivity but then settled on ISO 200 and 1/200. Programmed the camera Manual mode settings. Verified daylight white balance.

Then I remembered the mirror lock! So I dove into custom settings and, in conjunction, programmed a 2 second self-timer action.

Checking the evening's timing. Sunset at 9:03, sunrise 5:31. Moonrise at 7:07, moonset 5:24. Remembered we were in evening ISS flyovers. Found at event at 10:52 PM with the space station flying toward the Moon.

6:10 PM, Wednesday 7 June 2017. I had everything ready to go.

9:43. Shot my first image.

9:46. Found the camera off. Shot my second image manually.

9:50. Shot another photograph.

Moon shot with zoom at 55mm

9:51. Checked the camera rig. The camera was off again. Weird! I wondered if it was not getting power.

Rhonda liked my blinky LED ice cube things under the tripod.

I moved the AC power to a different socket in the extension cord. Got it sorted...

10:18. Rhonda heard the camera clicking. Yeah!

10:38. The camera was still working OK. Checked it. Explained to rho how I had programmed the intervalometer.

11:27. Rhonda reported the Moon was out of the view. I didn't think to check the time, how long the run was, when I started. [ed: About an hour and 15.]

Checked SkyTools 3 Pro to see if it was before or after the meridian. I found it was not there yet. Meant it was still climbing.

I considered zooming out and conducting another run. Rhonda helped.

11:33. Set the kit lens to 35, reframed Luna, crudely focused, shot a random shot, and let the intervalometer resume. Checked the power supply on the dew heater: OK.

11:35. Started the second run.

Moon shot with zoom at 35mm

12:53. Heard the camera click.

1:10. Stopped the imaging run. Checked the NOCO lithium-ion battery. OK at three quarters full.

1:18. Brought the imaging rig inside.

1:25. Checked the photos quickly, on the back screen. Looked like I got lots of data. Good.


Forgot to shoot darks again!


Stacked the 55mm and 35mm series.

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