What Could Possibly......

[Tommohawk]

It's a clear night, the wind has dropped the forecast is good.... what could possibly go wrong?

Fingers crossed

[jrastro]

Don't jinx it...  

 

 

[Grotemobile]

All these have  gone . Totally clear on the South Coast.

That has put the mockers on it.

 

[baldeliftman]

Cloudy here weather man says clear at 23.00 fingers crossed. 

[Tommohawk]

Cheers guys - good luck!

[Stu]

Clear here currently, Jupiter looking good although, as ever, the seeing is a bit ropey.

[Uranium235]

Gear out and PHD ticking away nicely, forecast says I might get buzzed by cloud around midnight - but im hoping thats going to be wrong.

[wimvb]

If you miss 'em, we have plenty of clouds over here. But that's ok, nights are too light for imaging anyway.

Good luck imaging

[DaveS]

Running 2 hours of L on M101 with the 130P-DS after repair. PHD2 is showing one of the best graphs I've seen despite the balance being way out, and in the "wrong" direction. With the Astronomik CLS-CCD filter I can get 10 min subs at 1x1. Without it I'd be hard pressed to get better than 2.

[Uranium235]

Just popped out to tweak the focus, and Arcturus displayed a distinct fuzziness around it... hmmmm hopefully its just a bit of passing flluff as the majority of the sky seemed ok(ish). A bit twinkly, but still plenty of stars about.

[laudropb]

Raining here once again.

[Tommohawk]

37 minutes ago, DaveS said:

Running 2 hours of L on M101 with the 130P-DS after repair. PHD2 is showing one of the best graphs I've seen despite the balance being way out, and in the "wrong" direction. With the Astronomik CLS-CCD filter I can get 10 min subs at 1x1. Without it I'd be hard pressed to get better than 2.

hope that goes well. Am also on m101 but PHD2 giving grief. Dec not clever at all. How can it drift off so much... Its sawtoothing like PE but shouldnt have much to do. I tweaked the belt dive and high hopes, but looks like half the subs will be dud.

 

Any thougts on why Dec would drift so much? PA should be spot on.

 

[DaveS]

I don't know, but my first thoughts would be to check the balance, perhaps it's *too* good in dec? With the guiding going back and forth?

The other thing I would check is your PA again. Did you drift? and if so how close did you get it?

I realise you have probably been round the block in this, but I'm just throwing these out as something I'd double check if I was getting dodgy guiding.

[Tommohawk]

Hi Dave. Well I don't drift align if guiding. I just checked balance and its definitely weighted one way, so shouldn't  be any backlash. Very odd.... it seems to suddenly just wobble off, and them overcorrects. The pattern seems to repeat, but it can't be PE coz it shouldn't be continuously driving one way. Mystified.  RA is fine.

 

But it does answer the question.. "what could possibly go wrong?"

 

 

[Tommohawk]

OK, well hope everyone had a good night or two - seems the weather wasn't so clever further north, and I guess imaging must be a very seasonal affair if you're way north. But at least you get the Northern lights by way of compensation. 

Anyhow, despite guiding problems I managed to get a pretty good M101 - posted in imaging. 

I really cant see why the Dec gives such a twitch now and again - maybe cable drag, but looks OK. Funny thing is that the last couple of nights it was OK initially and then seems to get worse. Also I had a read-up on PHD2 and it seems the default "resist switch" algorithm may cause problems. I can see the sense of it - PHD isnt expecting significant changes so it waits for a few before sending a correction. Trouble is if there is an error, it doesn't correct till its too late and then overcorrects, and then the same problem on the other side. The "fast switch for large deflections" option is ticked, but it doesnt kick in soon enough.

So, next time I'll try the "hysteresis" option ... (what could possibly...)