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Monsoon Season Ending;
Moon Imaging Tests, Critter Visitor

Posted: 24 September 2015

Sunday, 20 September 2015, surprisingly dawned clear (forecasts had cloudy skies as another storm system was approaching), but it was windy at times. However, true to the forecasts, the sky began clouding up mid-day. The rain arrived Monday morning, 21 September, with a total rainfall of 0.68" by midnight. Cloudy skies continued on Tuesday, 22 September. I checked the POD for leaks and there were none. The resealing job I did at the pivot joints on 7 September worked. But the monsoon wasn't quite finished with us for the season (15 June to 30 September). A little before noon on Tuesday I looked towards the west and saw this nasty storm approaching:

Click or tap on image for 180° panoramic photo

When it arrived a few minutes later it dropped 0.3" rain in about 15 minutes. Once the storm departed the sky began clearing. With the chances increasing that I could open the observatory Tuesday evening, about 1600 MST I went to the observatory to clean off any residual water from the dome, but it had already evaporated by that time. The inside was dry, as expected. Shortly after my check another storm to the southwest brought extensive cloud cover as sunset approached, ending my chances to open the observatory that night. Wednesday, 23 September, dawned clear, with a clear sky forecast for Wednesday night. Some cumulus clouds did appear during the daytime but were mostly gone as sunset approached.

Open: Wednesday, 23 September 2015, 1815 MST
Temperature: 90°F
Session: 859
Conditions: Mostly clear, humid

1822 MST: sunset. Viewed Saturn at 83X and 222X in the 8" LX200-ACF telescope. Seeing not ideal. 1830 MST: viewed the Moon, 83X and 222X, but although the Moon was higher in the sky than Saturn, seeing was still not good. Humidity was high, causing part of the poor seeing.

The main purpose of this night's session was to do some imaging tests of the Moon to determine how best to image it during the upcoming Perigee Total Lunar Eclipse on Sunday evening, 27 September. Since the Moon would be unusually close to the Earth I wondered if I would need to use a focal reducer on the telescope. My first test was with the iPhone 5s, afocal 77X (26mm eyepiece), using my new Orion SteadyPix Universal adapter (review forthcoming). The Moon was visible in the 26mm eyepiece field-of-view (FOV) and the iPhone camera was able to capture the entire disk (barely):


As the Moon gets a little closer over the next few nights and more illuminated as it approaches full phase, it is likely that the focal reducer would be needed if I decide to use the iPhone for eclipse imaging.

I also took these iPhone photos, afocal 222X (9mm eyepiece) with the SteadyPix, of the northern and southern regions of the Moon:



As I was ending the iPhone Moon imaging I noticed I had a visitor in the observatory, and a rather large one:


Next, I did some FOV checks using the D7200 DSLR at prime focus of the 8" telescope. I first tried using a visual back + diagonal but could only get about 1/2 of the lunar disk in the FOV. Added an extension to the visual back, which added a little more disk but still not the entire Moon. I removed the diagonal and tried extension + visual back and visual back alone. Neither allowed the entire lunar disk to be in the FOV. This full-frame D7200 DSLR photo, 1/640sec, ISO 400, was taken using the focal reducer + extension + visual back (no diagonal):


So, as I expected, I will need to use the focal reducer if I decide to image the eclipse with the DSLR.

1918 MST: the spider had disappeared. Wonder where he/she went.

1935 MST: final look at the Moon, 83X.

Close: Wednesday, 23 September 2015, 1950 MST
Temperature: 74°F
Session Length: 1h 35m
Conditions: Clear, but humid

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