A work in progress ...NGC 253

[ZeroID]

NGC 253, Sculptor Galaxy. 2 hrs 36 mins over two nights so far. Hoping to get a few more hours on this yet if the weather cooperates. Slightly elongated stars as I have a guiding oscillation problem at present, RA hunting E\W a few pixels over a 4-5 second period. Working on it.

[Placidus]

Coming along nicely.

Two things that can cause the hunting: too much guider gain, and incorrect balance. One wants the balance to cause the scope to want to move ever so slowly to the east when you release the clutch. If it wants to move to the west when you release the clutch, you'll get east-west lurching.

A rare one: When our MI-750 fork mount was first delivered, it suffered from another cause. It was built to work in the Northern hemisphere. In the southern hemisphere, the RA worm gear would climb up the face of the big bronze RA gear, and then slip back down again. In the Northern hemisphere this did not happen because of the way the pressure loaded worm carriage was built. Rather than sending it back to California at enormous expense, we modified the carriage by adding some additional bearings to hold the carriage down. That fixed it.

Best,
Mike

[ZeroID]

Hi Mike, looking into that already Changed the weight\bar length ratio yesterday, hopefully I'll test that tonight. Also checking SCP alignment although that should be pretty good unless I've bumped it somewhere.
Already been playing with gain in PHD2. Just hoping I haven't got any worm gear contamination or such. Might have to pull it all down again.

Cheers
Brent