The target will be 19 degrees east of the 98% waning moon, so that will make clean skies important. The duration is a good long 2.2 seconds, mag drop=3.2 in V so we may still see some signal at the bottom
Alt=30 Az=120 in NW Aquarius, straight down 20 degrees below Altair
Weather looks good. no clouds, and the Ft Ord profiler shows the marine layer is being pushed downward, now at about 900 ft, so 1600 ft at Karl's should be safe. Coastal areas not, though.
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Spent the evening at Karl's on asteroid hardware and software conversation, then set up at "water truck turn", all 3 of us, to get this event. It'll be a useful exercise to see how well the timings agree, and compare to the PyOTE determined confidence limits. We all 3 got positives.
The star was very dim and the sky was quite bright due to the full moon not far away and the low altitude. This is why I felt it best to not spend extra time and gas money trying to get different chords, since I thought each of our chords would be only marginally significant when analyzed.
I had to integrate almost too long to keep the sky itself from saturating. Had to choose carefully to not saturate pixels in ref stars. I had to do manual time stamps in PyOTE as I got "No 1PPS" errors coming and going randomly, and the histogram of pixel values was quite high with the nearby moon and block = 8 frames = 16x setting. But at frame = 2580 when the event was supposed to happen, I got a clear clear enough full disappearance. I recorded via Startech. Everything worked this time. I learned that my Orion Dynamo battery when pulled on AC, has a periodic fan which makes it sound like Darth Vader. But, it worked and stayed on for the entire time.
Reductions; I had to narrow the mask to 2.4px to get a better signal. At 3.2px like I default to, I was getting many single-frame drops to zero, High sky noise I believe. So, when the sky is bright, it's important to narrow the mask as much as possible. PyOTE said my blocks were 8 frames = 16x setting. While the event came at the right time, it has two deep integrations with a more normal brightness integration in between. Double occultation? Unlikely, and probably just normal noise.
I note that the drop was only 1.3 magnitudes, not 3.4 magnitudes.
magDrop report: percentDrop: 71.0 magDrop: 1.342 +/- 0.910 (0.95 ci)
DNR: 2.24
D time: [06:19:55.4040]
D: 0.6800 containment intervals: {+/- 0.1654} seconds
D: 0.9500 containment intervals: {+/- 0.6409} seconds
D: 0.9973 containment intervals: {+/- 1.5112} seconds
R time: [06:19:57.0040]
R: 0.6800 containment intervals: {+/- 0.1654} seconds
R: 0.9500 containment intervals: {+/- 0.6409} seconds
R: 0.9973 containment intervals: {+/- 1.5112} seconds
Duration (R - D): 1.6000 seconds
Duration: 0.6800 containment intervals: {+/- 0.2722} seconds
Duration: 0.9500 containment intervals: {+/- 0.8233} seconds
Duration: 0.9973 containment intervals: {+/- 1.8759} seconds
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I got a 1.8 sec event for Poldimeri, 16x on Laguna Creek rd, July 1. The curve has an odd shape, sharp drop D then curving slope R, not sure if it's just noise or what. The background was noisy due to a 98% moon 19 deg away and 16x is not a good resolution. Since all three of us were recording at the same spot, it will be interesting to compare. Maybe Karl's 32x recording can be salvaged.
RN: I note that like mine, Kirk's mag drop was only 1.3 magnitudes, not the predicted 3.4 magnitudes. Perhaps a new binary star poorly diagnosed in this difficult event??
magDrop report: percentDrop: 69.2 magDrop: 1.277 +/- 0.740 (0.95 ci)
DNR: 2.25
D time: [06:19:55.1247]
D: 0.6800 containment intervals: {+/- 0.1435} seconds
D: 0.9500 containment intervals: {+/- 0.4773} seconds
D: 0.9973 containment intervals: {+/- 1.2205} seconds
R time: [06:19:56.9932]
R: 0.6800 containment intervals: {+/- 0.1435} seconds
R: 0.9500 containment intervals: {+/- 0.4773} seconds
R: 0.9973 containment intervals: {+/- 1.2205} seconds
Duration (R - D): 1.8685 seconds
Duration: 0.6800 containment intervals: {+/- 0.2408} seconds
Duration: 0.9500 containment intervals: {+/- 0.6847} seconds
Duration: 0.9973 containment intervals: {+/- 1.4852} seconds
Difficult to find the field in the full moonlight and small FOV, but eventually succeeded, just befoe the event. He saw a positive on screen, as I did. I confirmed the positive on playback.