PHD guiding settings

[LouisJB]

Hi,

Just wondering. So I've had guiding working when using the little 130P and it's been great. The guiding is through an ST80, the mount is an HEQ5 pro.

I've not had a chance to try with the 200, but tonight I got as far as starting calibration at least before having to give up as clouds came over and it lost the star and was reporting poor signal, but it also said calibration failed, disabling dec.

Maybe this was due largely to the clouds, but my question is really,

should I be using different settings between the scopes. If so, how would I know what I should change?

Or doesn't it matter, since the guider scope, guider camera and mount are the same as before.

[Thalestris24]

Hi,

Just wondering. So I've had guiding working when using the little 130P and it's been great. The guiding is through an ST80, the mount is an HEQ5 pro.

I've not had a chance to try with the 200, but tonight I got as far as starting calibration at least before having to give up as clouds came over and it lost the star and was reporting poor signal, but it also said calibration failed, disabling dec.

Maybe this was due largely to the clouds, but my question is really,

should I be using different settings between the scopes. If so, how would I know what I should change?

Or doesn't it matter, since the guider scope, guider camera and mount are the same as before.

Hi LouisJB

I'm no expert but I don't think it should matter too much which scope you're ST-80 is attached to. If you do a search on here you should be able to find some examples/tutorials re: settings. I actually use a 9 x 50 finder guider - also with a QHY5L-II. Initially I used it to guide my ST-80! Then I attached the finder guider to a 150pds and it still works fine.  From what I've experienced the guide camera seems more sensitive to exposure than focus so you maybe have to try a few exposure settings. Also, I set the camera gain to 70 which seems to work ok - it's quite a sensitive sensor. Try and pick a star with fairly good S/N. Clouds are a bummer! Even high clouds that you can hardly see can affect things as can light pollution though PHD seems pretty robust. You've probably seen the PHD window vary in brightness quite a lot from moment to moment. Well it does on mine! I'd like to see if I can fit a lp filter on the guider somewhere. I've only been using my guider setup this week so using a guide camera is very new to me. Hopefully we'll get there! 

All the best

Louise

[r3i]

If you're using the same camera + guide scope configuration with different imaging scopes, then you don't fundamentally need to change your PHD settings to get it calibrated and guiding. 

However the longer FL of your 200P will place more demands on your whole setup, and some tweaking of the parameters in PHD such as aggression etc. may (or may not) improve the guiding performance.

As Louise said, a nice clear guide star needs to be available throughout the calibration operation.  Try to aim for 10-15 calibration steps - this is the generally recommended number (you increase or decrease the calibration step size to do this).

[LouisJB]

thanks for all the advice. Good to know that fundamentally nothing needs to change.

I realise my HEQ5 pro defaults to guiding rate x0.5 and previously I've remembered to bump that to 1x before guiding. Last night in a rush I forgot (also forgot to connect guider cable up first, so that didn't work too well!).

In the past I've been able to guide through clouds, but last night thick ones came over and all was lost, during calibration, so it's not really very definitive.

Think I need to try it out again on a clear night. Used to guide really nicely with the 130P, I know the 200 is bigger etc but I hope it will guide well enough still using that.

Louise, as you've been using the QHY5L-II (is sensitive isn't it, it images M81 and M82 in PHD when guiding in that area!) - can I ask, have you tried it at full res video for planets?

I can get mine to produce about say 20fps at 800x600, as soon as I try to go higher it seems to die with 0 frames and maybe lock up such that I have to restart it.

have you tried it like this and experienced issues or it working? I blame drivers, but it might also be the mac/VM combination. I'll try on a different laptop sometime, maybe it will work if I upgrade to a new macbook pro - like I need a good excuse!

[LouisJB]

BTW, should the HEQ5 default to guiding rate 0.5x? Seems like I'd prefer it at 1x and control the aggressiveness from PHD, how do you go about this combination?

[Thalestris24]

BTW, should the HEQ5 default to guiding rate 0.5x? Seems like I'd prefer it at 1x and control the aggressiveness from PHD, how do you go about this combination?

Hi LouisJB

Not sure on that... I'm sure there are more knowledgeable and experienced peeps on here that can advise better than me. But, fwiw, here are my current EQMod and PHD settings.

They're probably not optimal but they work ok with my setup. I'll have to have a tinker when I get the chance but if it's not broke, don't fix it! I'm a PC person so can't make any comments about Macs or their drivers...

I'm using a 9 x 50 finder guider so haven't used the QH5YL-II in a standalone mode. I could fit it to my ST-80 as you've done but I'm not sure how best (= cheap!) to attach the ST-80 to the 150pds.

I just processed some images of M44 - my fav cluster. I'm more into DSOs, especially star clusters and hope to image some galaxies too when I can get the opportunity to do longer exposures.

Cheers

Louise

[todd8137]

Hello I think it's hard to say use " use these or this set of settings " ,as if your mounts not got good polar align then my settings might not be any good give this a look

http://www.rosecityastronomers.org/resources/pdf/GuideToGuiding.pdf

Cheers pat

[LouisJB]

@Louise

Awesome, thanks a lot for that.

I'd be interested in your defaults on the HEQ5 pro, I think it's in the 'settings' menu -> 'guiding' (or maybe it's called tracking) and mine is 0.5x by default, but as I mention I've been changing it every time to 1x. What are you using be default?

I've never seem that EQMOD ASCOM page, am I even using ASCOM (I'm so clueless I'm not actually sure) - I just have QHY5L-II guiding port connected direct to HEQ5 ST-4 guider port.

Thanks for the PHD settings, very useful, I'll check what I have and try adjusting any params that are different if it's not working well.

I totally agree, if it ain't broke don't fix it.

BTW, I fitted my ST80 on-top of 200 (and 130) for just a few pounds. Price of a dovetail the same length as the lower one you're using. Drill two holes in it. Fit the ST80 rings to the bar by bolting from the underside of the bar into the rings. Then fit the bar on-top the 200 rings with standard bolts. I can get a pic if it helps, bolt sizes were odd but IIRC 1/4 whitworth and M5 are the two sizes in use there (with skywatcher stuff anyway).

It's not adjustable, but thats really a good thing as it's solid, rigid, so no flex etc

Also I've found it always picks up several stars to guide on, so I've never needed to adjust where it is looking (to-date anyway)

@Pat

thanks for the link. I always do do a decent polar alignment through the polarscope, enough so as I found out last night that I can get 45s with no guiding and no trails. I know you can get much better, but I think that is then accurate enough to then auto-guide with, without loads of problems due to overcorrection. 

[Thalestris24]

@Louise

Awesome, thanks a lot for that.

I'd be interested in your defaults on the HEQ5 pro, I think it's in the 'settings' menu -> 'guiding' (or maybe it's called tracking) and mine is 0.5x by default, but as I mention I've been changing it every time to 1x. What are you using be default?

I've never seem that EQMOD ASCOM page, am I even using ASCOM (I'm so clueless I'm not actually sure) - I just have QHY5L-II guiding port connected direct to HEQ5 ST-4 guider port.

Thanks for the PHD settings, very useful, I'll check what I have and try adjusting any params that are different if it's not working well.

I totally agree, if it ain't broke don't fix it.

BTW, I fitted my ST80 on-top of 200 (and 130) for just a few pounds. Price of a dovetail the same length as the lower one you're using. Drill two holes in it. Fit the ST80 rings to the bar by bolting from the underside of the bar into the rings. Then fit the bar on-top the 200 rings with standard bolts. I can get a pic if it helps, bolt sizes were odd but IIRC 1/4 whitworth and M5 are the two sizes in use there (with skywatcher stuff anyway).

It's not adjustable, but thats really a good thing as it's solid, rigid, so no flex etc

Also I've found it always picks up several stars to guide on, so I've never needed to adjust where it is looking (to-date anyway)

@Pat

thanks for the link. I always do do a decent polar alignment through the polarscope, enough so as I found out last night that I can get 45s with no guiding and no trails. I know you can get much better, but I think that is then accurate enough to then auto-guide with, without loads of problems due to overcorrection. 

Hi again

Not sure what you're referring to - which menu? As I understand it the mount will automatically track at a sidereal rate by default. It should track what you're pointing to quite well (as yours seems to) but, yeah, dependent on polar alignment. PHD just makes corrections because the tracking isn't perfect so constantly making corrections (guiding) allows you to take longer exposures. My setup is with eqmod via a Hitec-Astro Eqdir cable. I use Stellarium to locate objects of interest and then to slew to the object. PHD then maintains accurate tracking by locking on to a star via the guide cam and sending corrections to the mount interface if the tracking drifts. Strictly, when it drifts. I use APT to control my canon 1100d. Everything works well together via the Ascom drivers. I think you can guide directly through the ST4 port but I've not done that. I think when I installed PHD didn't specifically have the QHY5l-II as an option so I installed as an Ascom compliant camera.

It may not be a good idea to copy my PHD settings (the defaults should work anyway) but if you do, make sure you have saved the original ones.

Thanks for the info re mounting the ST-80. I'd have to buy a drill first...

Cheers

Louise

[LouisJB]

Ahh right, I think I'm not using ASCOM at all, I downloaded a beta version of PHD that supports QHY5L-II direct, maybe that's in the main version now, I'll have to look for updates. I've had guiding working for 6mins +, but that was with the little 130P, so it remains to see how tolerant it is with the bigger tube and with the longer focal length...

I also use stellarium to control the pointing (via USB->serial->handset socket) but tend to use the handset when outside as the mount is goto anyway.

The menu is in the HEQ5 pro settings menu, think it controls the sensitivity of the guiding port, perhaps if you're not used the st-4 port you never noticed or needed it - possibly that's what all your ASCOM settings do instead.

So I think our setups are slightly different in that I'm not using ASCOM at all, but anyway that shouldn't matter much to guiding itself.

Think what I really need is a good clear night. I'm also much into DSOs and I've been taking some long subs on various targets. But since it was either full Moon and / or cloudy lately I tried video stacking of Jupiter and also better shots of the Moon most recently. The supernova in M82 got me targeting DSOs again, now I have the better tube and a coma corrector the weather really has decided not to play along yet.

I only got the GSO 200mm at Christmas and not had clear nights to try it properly, as with anything new, always a new learning curve to work out it's characteristics. So far the HEQ5 has been handling it just fine though, which is a good sign.

Hopefully one clear night an hour of experimentation I'll have it sussed again and it will be working like it was on the 130, fingers crossed.

thanks for the help.

[Thalestris24]

Hi again LouisJB

Ahh, right. I think I was beginning to realise.... Yeah, I don't use the hand controller at all. Mine is the Syntrek version and the hand controller isn't menu-driven so I was confused! However, if you're using the ST4 port then I think you have to select 'on camera' for the mount in PHD. I suspect that PHD takes over control and you don't need to use the hand controller either but maybe someone else here can confirm that - or not!

Cheers

Louise

[LouisJB]

Hi,

thanks. Yes, well I've had guiding working, so I must have done that or something like it (can't exactly remember) - but I think as I didn't need to use ASCOM I avoided it at the time. I don't generally plug into the controller unless I need to use stellarium to move the mount, which isn't really necessary for me in practice and just adds extra wires from the laptop,

So many options, guiding can be a black art - still I was getting good results, other than the effects of a larger tube (another +4kg) I hope it will work just fine again.

cheers, Louis