One Channel; Dozens of Bites

Another camping trip to Lac qui Parle State Park is over and it was a partial success. Let's start with the good news first: I got the blue channel data I needed:

Blue Channel of IFN

This is based on 1.72 hours of total exposure. Blue is usually the weakest channel in terms of signal and to me this looks decent. I'll try to get about the same exposure time for green and red. The strongest blue signal seems to be in the area just below Polaris; this may make that area whitest, which would be in agreement with what I've seen in other images.

[ Compare this to the luminance channel image in the previous post. Blue looks much less contrasty, right? Consider that the blue channel has only 1/3 (or so) of  the luminance signal, and that the above is based on 69 subs compared to the luminance's 177 subs; you can roughly figure this has an equivalent exposure of only 1/8 of the luminance. It didn't get lifted nearly as far above the background, so less contrast. ]

See the copyright notice? That's because my little blog is now getting scraped two or three times every day. Probably not because it's worth scraping, but simply because it exists. I can't really do much of anything that's effective to stop it without adding a CAPTCHA-like layer that would force everyone to choose which squares are motorcycles, or traffic signals, or whatever bots can't easily distinguish. I don't like those things, so I won't subject others to them.

Now the unfortunate part of the trip. The first night's imaging ended prematurely when somehow PHD2 became convinced it was using my imaging camera as the guide camera. This wreaked havoc with things: I started getting repeated timeouts, and a couple of the frames suffered from strange excursions probably caused by calibration mismatch due to different focal lengths. I shut down the sequence and tried troubleshooting, but it was simply not happy. It was already 1:30 A.M. so I decided to give up and get it worked out the next day. Here's what the misguided guider was doing on two of the frames:

Excursions along one of the guider axes.

This was clearly along one of the guider's axes. The guiding display of corrections looked like a strong square wave. 

The next day was unpleasantly warm (almost 90 F and dead calm). I redid PHD's hardware profile and collected the new dark/bad pixel frames it demanded. Things seemed to work; there was a steady stream of images. It also needed a new calibration, something I could only do once it was dark. As dusk fell the mosquitoes attacked in force. My Coleman shelter worked reasonably well to protect me, but all this reconfiguring was making me repeatedly get in and out of the protected area, each time allowing dozens of hungry mosquitoes in. Neither the usually effective Ultrathon or DEET products kept them off me. It was not fun.

There were thunderstorms already west of me in South Dakota, the last satellite images showed high blowoff from them headed directly my way. The forecast was for rain and possibly severe weather around 5 A.M., meaning I'd have to break down everything and pack it away before turning in. 

Between all that and how the bites on my arms and hands were welting up I decided to pack it in and  get a good night's sleep. As it turned out there was rain but the severe stuff went elsewhere. I was glad to have bailed on the night. 

I don't think I'll be making any more mid-summer trips to the park, it's just too buggy for this imager. What a change it was from the previous month's visit!

I'll only have some of the July new moon to see about collecting the red and green frames as my wife is having her second knee replacement done on the day of the new moon. I'll probably just wait for the Northern Nights Star Fest at the end of August, as that should be cooler, darker, and will have longer nights. Or, if that's completely clouded out the Iowa Star Party in October or any clear, dark nights I can get out to Eagle Lake.

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Tariff Watch: The Rokinon lens remains in stock at B&H at $449. This price is 22% above the February pre-tariff price, which is very close to the current tariff of 26% with South Korea.