RA calibration failed: Star did not move enough

[Sarek]

I was repeatedly getting this error last night when trying to get my guiding set-up working with an ASIAiir Mini. From memory I think the movements after 60 steps were something like 15?  

Are there any recommended settings to overcome this? My current settingss are :

Calibration step: 500ms

Max Dec Duration: 300ms

Max RA Duration: 300ms

[bottletopburly]

What mount , are you using Eqmod ? What pulse guide rates have yet set them at , if on default 0.1 set to at least 0.7 for both .

[900SL]

What focal length and camera? Calibration step may be too low. I use 5000ms for wide angle 

[alacant]

The settings don't make sense.

Perhaps best to start again. Enter only what you are asked. Change nothing.

Cheers 

 

Edited January 20, 2023 by alacant

[Sarek]

6 hours ago, bottletopburly said:

What mount , are you using Eqmod ? What pulse guide rates have yet set them at , if on default 0.1 set to at least 0.7 for both .

HEQ5 and using Eqmod. I just checked the guide rate and its been set at 0.5x so I could go up to 0.75x?

[Sarek]

3 hours ago, 900SL said:

What focal length and camera? Calibration step may be too low. I use 5000ms for wide angle 

ZWO 120mm mini, setting the focal length at 128mm (32x4)

[Sarek]

17 minutes ago, alacant said:

The settings don't make sense.

Perhaps best to start again. Enter only what you are asked. Change nothing.

Cheers 

 

I got these from a You Tube tutorial. I can't remember what the defaults were

[bottletopburly]

Here’s how mines set at

[900SL]

You have set the parameters too low. I remember one of the youtube so called experts recommending  values that were way out. 

 

 

 

 

 

 

[900SL]

11 minutes ago, Sarek said:

ZWO 120mm mini, setting the focal length at 128mm (32x4)

Try 2000 ms for calibration step and 1000 for ra and Dec. You've used values more suitable for long focal length off axis guiding

[Sarek]

1 minute ago, bottletopburly said:

Here’s how mines set at

Thanks. For now I'm going to try a pulse guide rate of 0.75 , 2,000ms for calibration step and 1,000 ms for the Max RA and Dec durations. Now I know these are the key settings I can hopefully  fiddle until I get it right

[Sarek]

2 minutes ago, 900SL said:

Try 2000 ms for calibration step and 1000 for ra and Dec. You've used values more suitable for long focal length off axis guiding

Perfect. I'll try that. I think I was impatiently playing around with settings after watching tutorials but because of cloudy nights never got a chance to try it out for real until this week.

[Sarek]

I managed to get it working! Thanks for all the tips chaps

Accuracy varies but it's mostly settled at around 1.9.  I don't know if that's good or not?  

[bosun21]

45 minutes ago, Sarek said:

I managed to get it working! Thanks for all the tips chaps

Accuracy varies but it's mostly settled at around 1.9.  I don't know if that's good or not?  

What scope are you using on your HEQ5? You should aim for around 1 or less. I was getting 1.1-1.3 with an EQ5.

Edited January 21, 2023 by bosun21
Typo

[Sarek]

9 hours ago, bosun21 said:

What scope are you using on your HEQ5? You should aim for around 1 or less. I was getting 1.1-1.3 with an EQ5.

I'm using an Evostar 72ED. Later in the evening I switched to guiding on a much brighter star and it was getting down to those levels - sometimes below 1. Almost all other settings I fiddled with made no noticeable difference once it was going.

I am surprised how much it varies. Got peiords of relative stability then it wandered up and down again.  I had my rig set up on the patio decking and I've learnt that stepping out onto that creates a lot of disturbance!

[WolfieGlos]

I have just upgraded to the HEQ5 and have been using it for the first time this week, and I have exactly the same equipment as you other than I have a canon 800d. Same county too oddly! 

I too had to set the RA and DEC rates high, I set them both to 0.9 and phd2 worked immediately. Mine runs very smoothly, no subs scrapped all week from trailing, a mixture of 90 and 240s exposures. Was the guiding stability due to just the decking movement? Mine has only varied on two occasions; when the mount got to the meridian and stopped, and whilst dithering.

[bosun21]

2 hours ago, Sarek said:

I'm using an Evostar 72ED. Later in the evening I switched to guiding on a much brighter star and it was getting down to those levels - sometimes below 1. Almost all other settings I fiddled with made no noticeable difference once it was going.

I am surprised how much it varies. Got peiords of relative stability then it wandered up and down again.  I had my rig set up on the patio decking and I've learnt that stepping out onto that creates a lot of disturbance!

Changes in the seeing conditions can affect your guiding accuracy.

[900SL]

As can wind. And set your tripod on something solid. On a deck is asking for issues with deflection and vibration.

Mine will pick up light footsteps anywhere near

[900SL]

Oh and one I forgot. If for some reason you are trying to calibrate near the pole, you might not get enough star movement. Stars obviously appear to move at different rates across the night sky.