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Quote: Too late!I had the smart tool for altitude, so decided to try the compass for azimuth. I was hoping for 2 or 3 degrees max, figured it was only $40 if not. I did not quite expect 8 degrees. At any rate, given both devices, I mounted them on my scope last night and took it out to the driveway. I had more confidence w/ the inclinometer (smart tool), as others have used it successfully. W/ the wayfinder I had several concerns: 1) accuracy, 2) backlight, and 3) directionality. For accuracy, concerns were justified. I calibrated the wayfinder and then used the magnetic declination setting to zero on polaris. I then tried to use the two to find things, with mixed success. My first attempt, M31, was off by 3 degrees of azimuth. M76 was found in the eyepiece (40mm, about 1.5 degrees). M92 two degrees off. Several stars were within a couple degrees azimuth, but two were four degrees off, and one was eight. Interestingly, when I finally rotated all the way around, polaris was only one degree off. I'm speculating that the "map" of the surroundings the wayfinder makes during calibration is off. Perhaps this was because I didn't do it evenly enough or some such. Another interesting point that didn't occur to me until afterwards was that I think the error was always in the same direction (of azimuth). If so, this would significantly ease the process. After all, searching in one dimension is much easier than searching in two. As far as the smart tool, it was always within two or three tenths, at most. My second concern was the wayfinder's backlight. Turns out this is not bright, is easily disabled, and actually somewhat useful. The wayfinder has to be mounted down on the rocker base, so it's a bit hard to see from up near the eyepiece. Situation might be different when I get to a dark site. My last concern was directionality, by which I mean that the wayfinder is designed to be mounted on a dashboard, facing forward. Facing the compass in the directy my mount is facing would mean mounting in on the "back", i.e., I'd have to get off the chair and walk around the scope to read it. I put the wayfinder on the side of the scope, meaning that it's 90 degrees off, PLUS the magnetic declination. The wayfinder's magnetic declination can be set up to 99 degrees, which would seem to be enough. However, it didn't seem that way, I seemed to need more like 105. So I left it at 95, meaning that I have to add 10 to each azimuth I look up on the computer. No big deal. Overall, it's good enough that I'm willing to spend another couple of evenings trying to work out the kinks. If I can't, I'll mount the wayfinder in my car and add a printed azimuth circle to the base (which will be a bit of a pain). Cheers, pete |