EQMOD pulse guide monitor graph

[Russe]

Hi guys,

Ever since I started playing with the RA sensitivity slider in EQMOD's pulse guide monitor I've become more able to stabilise my guiding and have finally breached my personal wall of 300s. Finally pin point stars at 600s.

I've read the usual EQMOD tutorial where it explains the basic curve shapes and managed to get away from the sawtooth appearance. But what I realise now is, what am I actually aiming for? A line more on the east side or more on the west?

Anyone got an opinion on the matter?

[swag72]

My opinion on the matter is to look at the subs you are getting first and foremost. If you are getting round stars at 600s then there's no reason you can't get them at longer exposures. Clearly what you are doing is right, so don't become a slave to the guide graph.

If I showed my guide graph people would probably say that there is no way I can get 30 minute subs looking at that and the errors that I get - But the proof is in the pudding and despite everything that the mountainous graph would suggest, everything is nice and round. My EQMOD guide monitor is equally frightening, I don't even look at it now!

Again, only my opinion, but we, as imagers, seem to spend a lot of effort in tweaking graphs night after night and never actually produce anything or look at what we can produce within the parameters we have.

I'm sure others will disagree with me, but get out there and collect data - Become a slave to the guide graph at your peril

[red dwalf]

my graph looks pants but i get good results also, it shot up the other night when first got going, twice, then settled to a lovely looking graph although saw tooth in shape it stayed reasonably flat

[r3i]

my graph looks pants but i get good results also, it shot up the other night when first got going, twice, then settled to a lovely looking graph although saw tooth in shape it stayed reasonably flat

I think PHD needs a little time to 'settle' after starting up.  A jagged graph just goes with the territory when imaging at a long FL. 

I've also tried playing with the RA & DEC sliders in EQMOD and I 'think' they help to get a slightly smoother graph but it needs more checking out.

[chrisshillito]

If you have a 'constant' drift error, as would be the case most setups, then a perfect guiding response would be to issue a constant correction. This would appear as a flat line in the eqmod pulse guide monitor. Whether the line lies to the east or west of the centre line mattere not - if the line is flat the guiding system is working optimally. If the line is flat and at the centre line then you don't need guiding at all!

Please be aware that poor guiding control (oscilating graph) doesn't mean a decent image can't be captured - the oscilations might be sub pixel.

As other have said, the ultimate measure of guiding performance is the quality of the subs being captured not the flatness of guiding graphs.

Chris.

[Russe]

Thanks guys! The battle of getting passed 300s subs is wearing my nerves thin. If I can't guide passed 10min I won't buy a better camera. I've worked on flex and now started playing with the settings. Hopefully my results will improve...

[Carina Lass]

If you keep refining your processes, they will imporve.

It's this one thing that makes us keep going - that perfect pinpoint star with a black backdrop on a 15 minute sub......

My graphs used to look like a Norwegian fjord. The stars were round (but a bit bloated.)

My graphs are now flat and the tiny stars that never registered before are now like little slots in the sky!!! You CANNOT WIN.

F10 is not kind.