[davewaldo]

Hi everyone!

I finally got a chance to test my curved rod barndoor tracker I made this week. I had heaps of fun last night making 2-3 minutes exposures for the first time! Overall I'm happy with the results however I have two issues I can see.

1. As you can see for the shots I've attached, the stars are drifting downwards (this image is of the CRUX area and is near paralel to the horizon and looking SE). So I'm assuming this is an alignment issue however I'm not sure how I need to change it. The method I used to setup was as follows:

I used a compass to orientate the barndoor south, corrected for magnetic deviation and made sure the base was level. This would ensure the altitude angle was correct for my latitude. I then made several 2-3 min exposures.

This was the best one. I'm guessing to fix this alignment I need to angle more to the left or right.

Issue #2 is a bit more confusing...

Not only are the stars drifting but they also appear as wiggly lines. This tells me my tracking speed is not constant. However I have tried both motorised and manual tracking with similar results. So I'm thinking that maybe as i turn the nut on the threaded rod it is not advancing at a constant speed. As though it is warped or something. I think this because if I do a 2 minute exposure I will get two peak wiggles, 3 min exposure 3 peak wiggles etc.

What do you guys think?

Cheers

Dave.