Thursday, July 4, 2013

Getting back outside

bounty by S Migol
bounty, a photo by S Migol on Flickr.

I've got the Greens
(not blues)

Beets and cucumbers from the garden.

This is what I've been doing recently, getting plants to grow in the back yard.

The image to the right shows what I pulled yesterday.
 The image to the left shows the kale that we'd been using earlier in the year.  It needed to rest and recover before it went to seed. 
 This is a long view down the garden space showing the raised beds that we're using.  In the scene is the beds of kale and carrots, behind are beets and leeks, and behind that are tomatoes.

...and then there's Bad News

I injured my foot on Monday and thus will not be attending the GSSP star party.  Was able to sell my tickets so it's not a big loss.

Instead, I've set up the scope in the backyard and am enjoying the chance to get some more sky time.

I tried a different method of polar alignment last night.
  1.  Alignmaster was OK but it still suffers quite a bit from backlash introducing errors.  I think that it is the quickest to get aligned if backlash is minimized.  I set TVC to 45 for testing.  Advantage of the Alignmaster is that it can give some control over where the ending star is and thus AZ vs ALT adjustments can be set.  I didn't do this last night but might try tonight.
  2. Gemini's PAC software also works well -- and seems to understand the way the backlash works.  Disadvantage is that it will do a deflection in a part of the sky where either AZ or ALT adjustments mean little apparent change.
  3.  Did the drift alignment with the DSLR like Marek does - 10 seconds to do a spot star, then one minute in RA at guide rate and then another minute back.  Gives a nice V shaped line.  This allows a clear, measurable reduction in the drift.  Takes about 6 minutes per adjustment.  Getting close enough already is important for this technique as it would be a pain to have to keep adjusting when very far off.
The DSLR method may be the fastest after all.  With the PHD showing a bright star, it makes it easy to measure the drift changes.  No backlash issues, either.

Last night, after all these efforts, I was able to see that for ALT, the drift was pretty good - minimal change in the 2 minute exposure (taken at 9 DEC).  For AZ, there was about a pixel (or 1.9 arcsecs) of drift in 2 minutes.  Maybe more.  Thus, in 20 minutes, there was noticeable rotation in the exposure.