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uhb1966

After action report - first and second night with my new gear (and no polaris for polar alignment)

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Night 1-first light
Took me from 2100 to 2330 to set up all the software. Another Hour to setup scope, USB-2-serial, etc. No direct sight to polaris. Put up only rudimentary polar alignment (with compass), then astrotortilla for plate solving. Problem: as i had a massive polar alignment error, i was on target, but with a severe tracking error- exposures of only  5 seconds already showed star trails. Did a nice shot of M42 (orion nebula) nevertheless.

(2 months break due to exceptionally bad weather)

Night 2
No astrotorilla available as VM software did not start. Setup only 15 minutes, but another 45 minutes to remember how to connect camera correctly to scope (was out of focus because i had a extension in-between that was unnessessary). Setup again roughly to north with compass. Entered coordinates, date,time. Start three star alignment. 4 out of 5 suggested stars covered by house. Repeated 2 times, always the same invisible stars . Sweared. Tried 2-star align, the same. Tried 1-star align-success, much bigger list to choose from for alignment stars. Wondered why on earth the programmer did these inconsistencies. Selected first star, slewed. Far off target. Finally realized that finder scope not correctly attached. Corrected this. Slew speed way too low- another 10 minutes until realized that "rate" button sets slew speed also during alignment. Success. Slewed to second star, aligned. Back to first star and realigned. Back to second star - directly in the crosshairs, mount tracks perfectly (at first sight). Relief. camera mounted and connected to laptop. Start taking images. Relized that there is still some error, but significantly lower than on first try (Okay up to 10-20 seconds). Shot images for hours until Orion reached trees. Happy

Next up: the mystery of tracking with second cam+PHD.... If i live to see the day that we have good weather again.

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good stuff, you got somewhere at least.

3-star align is annoying isn't it - stars I've never heard of, and are almost always behind a tree or even on the horizon, and almost always followed by 'alignment...   failed'

I 2-star align nowadays

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I only do a 2-star align. I've been told the 3rd star is to prevent cone error, whatever that is!

You sound like you've had the same experiences as me, but at least I could see Polaris! How mobile are you? Could you join an astro group and go out with them? I don't do any AP in my garden now as I go out with my group. As soon as there's a clear sky there's a group-wide email 'call to arms'. And you have all the help you need.

Alexxx

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Hi

Astrotortilla is a great time saver if you can get it working! Don't forget - it has a polar alignment tool. You need to be able to see east-ish or west-ish, and south-ish :) 

Provided you've managed to adjust your PA to within your fov, you can optionally use a little tool called Polefocus to help adjust it finer :)http://www.scopefocus.info/polar-alignment (download is at bottom of the page, far right).

Louise

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Night #3:

Setup and polar alignment only 45 minutes, although i had to polar align three times due to cable problems... and then the clouds rolled in, 2 hours early (According to clear outside!)

But hey, i still could observe Sirius 15 minutes visually, and learned something important: the sky does not have to be of pristine clearness; the scope seems to be able to penetrate at least very thin clouds :)

I wonder why it makes me feel so calm and relaxed when i have watched the stars for some time?

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