My Problem with PhD2

Check what's in the ASCOM driver and also what is set in NINA. I suppose you control PHD2 through NINA, don't you? By the way there is no such a thing as underexposure in AP.  Just more or less (read-out) noise.

Hello Mossyback
I will spare you a long story about my relationship with PHD2 and it is definitely not good.
I have been in this hobby for about 8 years and PHD2 has always been a mystery to me.
When you spend about 45 minutes setting up your setup before the sun goes down and when it is then possible to go out to start when darkness falls and spend another 30-45 minutes for PoleAligment Focus…etc and when you are finally ready for imaging and guiding is the last thing in the process…then PHD2 often comes with all sorts of technical things and matters and you really just want to start it to go to bed so why bother with all sorts of technical things!!!!
This spring I have invested in the Mgen 3 Autoguider System and I must say that it lives up to its reputation in terms of simplicity and it is almost ridiculously easy to use and now you can spend time on everything else other than scratching your head over PHD2 and its technical world.
What I want to say is that PHD2 in my experience is almost manual in everything and the differences between PHD2 vs Mgen3 is that in Mgen3 you can choose full automation of all the processes and just have to press the Guiding button.
I wish for everyone that the Mgen3 system was not so expensive because then more people would go that way.
morian

Yes of course, but something seems logical to some and not to others.

I have the exact same setup and only get a message about the guide rate (sorry, away for a bit so I can't check the exact message) but I answer whatever the message says and it calibrates just fine.  Make sure you are choosing to use directdrive as the guide method - not pulse guide.  The is the method that Bisque recommends.  I've never gotten pulse guide to work and it might be that it doesn't work.

Also keep in mind that the MYT tracks very well, so be gentle with aggression settings and I tend to use long-ish exposure times, sometimes as long as 5 seconds.  If you're too agressive, you actually get worse-shaped stars.

HTH,

Ron

I had the message from Phd2 when setting up a new mini pc that the new HEQ5 mount was not moving quick enough. So I checked for cable snags and thought everything OK. So I ran the calibration anyway and the guiding was very bad. But then I found a U tube video about changing the pulse guiding setting in Phd2 from the default of 0.1 to 0.5 to improve the guiding by increasing the pulse guiding. So I re ran the calibration and the message that the mount was moving to slow did not return. After that the guiding was the best I have ever had it, not missing any subs in 6h of 5 min subs. So I guess when running my rig previously on a laptop with default set to 0.1 I use to have throw out 20% of my subs due to bad guiding. So I am not sure why the default pulse guiding is set at 0.1 instead of 0.5 when if left the guiding is not going to work in most cases.
Hooe this helps

Thanks for all the responses.

Next Steps:

Check settings in ASCOM
Check settings in N.I.N.A.
Check settings in TSX
Run The Wizard for my gear setup
Check that mount is running Sidereal in both TSX and N.I.N.A.
Check aggression and exposure times in PhD2

I'll then run Calibration and see what happens. I'll report back as soon as I get a clear night.

Thanks for the help.

Hank

I don’t know if you got an answer. 
I can guide in the same target indefinitely and never ever have a sub to throw away because if poor guiding. 


try going into your hand controller set guide rates to 50% sidereal it might be something like 0.5  anywhere between 50-70% 

Good PA alignment , PA drift alignment or NINA. I use Sharpstar and video feed from my camera ToupTek camera with a simple driver you can get video. Takes under a min to get excellent PA. 

Go in to set up wizard let it run for 600s
stop it wait for backlash measurement. This will help get your guide settings in the ball park.

(Learn what all measurement mean at the end of set up wizard. It’s very easy if your stuck screen shot paste into chat Gtp. Ask what does this stand for. )

I don’t have a lot of backlash in my mount so I don’t apply the backlash compensation but it may work for you. 

I offset my OTA slightly normally nose heavy and offset the RA ringer so the motor is always lifting RA . If your OTA is on the east side of your mount offset the counter weight to the west. Not crazy amounts! Just a bit or the telescope will oscillate and guiding will fight that. (Butterfly effect)

The above is the absolute foundation of guiding First principles 

Guide settings is where the art form comes in and true for all guide software just some do it differently than others. 

Make sure your guide scope imaging scale size is set properly. I use OAG and guide at the same resolution as my imaging camera. My imaging resolution is just slightly better than average local seeing conditions. 

Minimum move is har far the star can move before a guide command is issued. The number here is relevant to image scale. Depending on PA gearbox error is how small you can set this. It might even change slightly night from night depending on seeing conditions. It’s like the damper in the suspension. Agression setting is like spring stiffness you don’t want that too high obviously. You need to play with this to work out the relationship. The hysteria setting is like smoothing out the sine wave by making predictions based on past behaviour. This setting is the period of time used to make the average correction. There are other advanced settings which you will need to read and understand. 

Image exposure time can smooth out bad seeing is and average actually error. I tried to guide at 2-3s exposure. If you are aligned well then it is only high frequency you are smoothing out like mechanical defects. 

and some nights seeing can be so bad you think your gear is broken and it’s all worthless and a waste of money. If nothing seems to be working look at how much the stars twinkle. Twinkle a lot no point in doing long exposure photography… 

clear skies good luck !!

Hi Hank, calibration asisstant has the option to guide on one parameter only. So maybe you gave this option ticked.