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How to use AstroArt 5 for guiding?


Gina

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I have had AA5 for some time now and would like to try it for guiding.  Unfortunately the manual doesn't match the software and I can't see how to get AA5 working with a Lodestar X2 and EQMOD ASCOM mount control.  I have been using PHD but having problems with it.

Could someone please guide me into using AA5 for guiding?

Thank you :)

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This is something I'd like to know as well. I can get AA5 to recognise my QHY5 II guide camera, but when I open the guide window after selecting a star all I see are rendom pixels. So I'm stuck using PHD.

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He does!

It is a palaver to get it going but great once it's running. I'm busy building outside now but I'll find a sec later to talk you through it. 

I like it.

Olly

Thank you very much Olly :)

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OK, here we go, from the toolbar;

Plug in - CCD camera, choose from the drop down and say connect. (When I use an Atik I check high priority but I don't think the Lodestar asks for this. 

Back to CCD window;

Settings, Bin 2x2.

Set exposure time and take a shot.

Draw box round chosen star.

Focus/Guide button. Focus button to use FWHM. Once focused, back to CCD conrtrol window,

Focus Guide button. Guide window opens with star. Don't touch it yet!!

In Control Panel press Setup then Telescope. In this telescope control window choose the right com channel for your camera in the drop down then in this same window press Guide.

Now you can go back to the guide window and click Connect Telescope.

Telescope control window, Press Automatic calibration. It will do the usual NS, EW routines. When it says it's done,

Guide Window, Mark Guide Star.

Phew! By this time you might be wishing to return to pushing here dummy, but the above routine becomes second nature and takes thirty seconds at most. Now for some features which I'll explain.

Guide Window, Statistics. This is brilliant because the scattergraph runs all night and records any bad hit. If there are none then you don't have to look for trailed subs anywhere. The graph is also very informative. A set of hits in two clusters slightly apart says 'backlash,' for instance.

Telescope Control Window. Some pointers;

Telescope Speed in RA and Dec refers to the speed at which the software thinks the mount moves in response to a command. If the mount is over reacting, tell the software that it has a higher speed and it will send smaller commands. So high numbers in Telescope Speed mean low aggressivity and vice versa. I find autocalibration gives an over aggressive setting so I often raise the speed numbers.

Sometimes AA's calibration gets the direction of correction wrong and it steers the mount off course. Just check Invert x or Invert y as appropriate.

Meridian flip, just Invert x after the flip.

In Guide WIndow, Current, you can disable one or both Dec inputs. Often useful in avoiding backlash issues.

That's about it. Your settings will be remembered for next time. 

It's a messy setup with a lot of little windows open but it gives transparent control over the parameters, which you can adjust in real time while guiding.

The scattergraph is such a useful tool. Personally I like it, but I've been using it for 8 years. I like PHD when it works but I don't feel so at home in adjusting it. This is what we like to see...

Capture-X3.jpg

That's the EM200 on blistering form.

Olly

PS There are drivers available on the AA5 website and the writers do respond to Emails.

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Made a start and found and installed the AA5 Lodestar camera driver.  Found camera fine and I was able to capture an image :)  Just a house on a far hilltop but so far so good :)  Proves camera is detected and can capture images - a good step forward :)

It's almost trotally overcast ATM so that's it for now.

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A clear area of sky in spite of rain forecast so I'm experimenting.

It's working :)  The corrections were far too agressive so I've upped the speed to the m\aximum of 50 and it still seems a bit aggressive.  Meanwhile I have the imaging system on a DSO and capturing NB data.

Here are some scattergrams.

post-13131-0-38823100-1412977278.jpgpost-13131-0-63748700-1412977226.jpgpost-13131-0-34585300-1412977264.jpg

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And this is the latest Ha sub of 5m unbinned.  Histogram stretched in Ps and resized for upload, saved in PNG format.  Second image is cropped without resizing so pixel for pixel.

This shows that guiding is working fine :)  RESULT :) :)

NGC 1499

post-13131-0-81695100-1412977862_thumb.ppost-13131-0-23334800-1412978139_thumb.p

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A huge thank you Olly :)  Your instructions worked beautifully.  I'm now not surprised I couldn't get it going before - that is certainly a highly circuitous procedure to get it working :D

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Gina,

Olly has done a great job of explaining the AA5 guiding. Many thanks, Olly.

I use AA5 with the C11/ reflective slit guiding (spectroscope) on the NEQ6pro with EQMod.

I don't have it set up right now but I do remember that the guide settings had to be changed in EQMod to improve the "aggression"

Hope this helps.....

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OK - reduced rate in EQMOD from 0.5 to 0.3 in both RA and Dec and it seems better.  Getting misty now so I've stopped image capture.  Guiding is still going strong though :)

post-13131-0-71416500-1412983348.jpg

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I don't use EQ Mod so I can't comment on how that works, I'm afraid. I guide through the ST4 system.

I'm assuming you're guiding at a long FL because the trace looks very wild indeed compared to what I'm used to seeing using 400mm guidescopes. The one I posted earlier was exceptionally good at 0.02 average, but 0.06 might be more typical.

However, it ain't the trace you hang on the wall and the subs look tight.

Glad you're back in business, Gina.  :grin:

Olly

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OK - reduced rate in EQMOD from 0.5 to 0.3 in both RA and Dec and it seems better.  Getting misty now so I've stopped image capture.  Guiding is still going strong though :)

attachicon.gifCapture 4.JPG

In this final trace, Gina, the mount spends most of the time under-correcting since almost all of the guide hits take place on one side of the line. There is no overshoot. This may well be no bad thing. A slight increase in aggresssivity (lowering the speed values a tad) might improve it further.

But just occasionally a wildly over-aggressive action occurs in both axes. It would be good to know why this is and what you can do to stop it. Backlash would be one possibility. The overshoots might be a swing across the free play in mesh. However, I'm not too sure that it will be this because recovery is so fast. The next correction is from the right place. WIth backlash the mount usually sits on the other side of mesh for a while before falling back to its preferred side.

One adjustable parameter I didn't mention is 'Dont guide when drift is less than/greater than... ' (and you put in a value.) The 'greater than' value is just intended to disable the guider once all hope is lost. It stops the guider vainly driving the mount all over the sky when the clouds come over.

The 'less than' is more critical. Mounts with low PE seem to prefer a slightly higher value in here. It means they get fewer commands and, therefore, are less likely to start overshooting and generating guide oscillations. It might be worth experimenting here, upping the value, maybe. This is all in the 

Telescope Control window.

Rather thick of me not to spot this at once but it's just struck me that both axes experience over corrections simultaneously. Now this is very odd and a huge clue. My two thoughts are 1) Something is snagging. A cable, etc. (Wouldn't that be nice and easy to fix!) Or, 2) Something electrically or electronically common to both axes is producing the spike. Power supply? Some kind of surge? Or could it be something in the way pulse guiding works? Chris Shillitoe's your man there. Or something in the Lodestar itself?

Interesting stuff, espeically since you have the luxury of thinking about it while it is still good enough for excellent subs.

Olly

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Thank you again Olly :)

My setup is probably a bit strange :D  I have an OAG on my MN190 with the Lodestar on that for guiding.  This was initially for imaging with the MN190 but I added the Esprit 80ED Pro on the top of the MN190 with a heavy duty aluminium bar on the top of the MN190 scope rings.  As I already had a guider on the MN190 I though I'd try it guiding for imaging with the Esprit and it worked fine.  So no need to fiddle around with a separate guide scope :)  So I'm guiding with a 1000mm FL guide scope and imaging with a 400mm FL frac.  Cart before the horse?  Maybe but who cares if it works :D

I'll try lowering the speed values a bit and see if there's an improvement and also look at 'Dont guide when drift is less than/greater than... '.

I don't think there's any cable snagging as I've taken pains to tie the cables appropriately.  The main bunch is in an umbilical with a zip sided nylon sleeve fastened at the ends to pier and scope dovetail.  Single cables are tied to whereever is available. 

Interference spikes are another matter.  This could well be an issue.  I have 3m power cables from the warm room power distribution box to the scope and mount and no suppression/decoupling at the scope end.  Alright, I own up - as an electronics engineer, that is a cardinal sin :D  But the rush to get something working and get some imaging in seems to cloud the mind :rolleyes:   I am going to make a new power and USB distribution box for the scope end anyway as I'm adding extra scopes and cameras to the rig.  The mount power could probably do with some interference suppression too.

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