Imaging with the 130pds

[alacant]

1 minute ago, Jim Smith said:

was at 0.7

That's fine.

Post the phd2 log if you like.

[Jim Smith]

3 minutes ago, alacant said:

That's fine.

Post the phd2 log if you like.

Thanks. Guide and debug logs attached.

 

PHD2_DebugLog_2022-05-04_220035.txt PHD2_GuideLog_2022-05-04_220035.txt

[Bibabutzemann]

2 hours ago, Jim Smith said:

Thanks. Guide and debug logs attached.

 

PHD2_DebugLog_2022-05-04_220035.txt 5.15 MB · 2 downloads PHD2_GuideLog_2022-05-04_220035.txt 126.34 kB · 2 downloads

im pretty positive your mount never received the guiding commands which are displayed in the log. 

The up and down of the RA is the periodic error (peak to peak is arround 13min), the linear north movement of the DEC is the polar allignment error. This is a graph you would get when you run the guiding asstistant while guiding is turned off.

Also the periodic error seems to be pretty big for an AZ EQ5. Is this a new mount?

[Clarkey]

4 minutes ago, Bibabutzemann said:

im pretty positive your mount never received the guiding commands which are displayed in the log

Certainly in the later logs, but the first guiding log (after the calibration) seems to be guiding initially. At about 22:13 it seems to stop guiding. Looking at the text log, guiding is stopped at frame 68.

[Clarkey]

Thinking about this a bit more I was wondering how you are guiding - I assume a directly from the PC using a EQDIR cable. If so, it looks to me like a dodgy connection. Every so often the mount tries to correct then stops again (in addition to the normal PE).

[Jim Smith]

1 hour ago, Bibabutzemann said:

Is this a new mount?

About 6 or 7 years old I think.

[Jim Smith]

1 hour ago, Clarkey said:

Thinking about this a bit more I was wondering how you are guiding - I assume a directly from the PC using a EQDIR cable.

Yes...Lynx Astro FTDI EQDIR USB Adapter for Sky-Watcher Mounts to Windows 10 laptop running PHD2, EQMOD and Sharpcap.

[Jim Smith]

Here is my new set-up with the longer, Losmandy dovetail bar. (Since fitting the Telrad finder, I had a lot of trouble finding good positions for the tube rings that also allowed me to get balance with the original Vixen dovetail with it's screwheads poking out the bottom. Also, it was green!) This should be much more stable and might help with my autoguiding problems. I also need to think about organising the cables a bit better. It's too easy for them to catch and rub at the moment.

[spillage]

@Jim Smith

How is the balance of the scope when you release the clutches? I would route the cables from the scope down the dec and along the ra if you have enough cable to allow dec full movement. Not sure if you are aware how much rotating the scope in the tubes also helps with balance.

 

*Might be worth loosing the telrad and using plate solving instead.

Edited May 7, 2022 by spillage

[alacant]

3 hours ago, Jim Smith said:

might help with my autoguiding problems

Nice.

A few ideas:

• Fit a rigid rail to tie the top of rings. Mount the guide telescope to that.
• Black shower cap.
• Balance: Rotate the whole tube in the rings ~180º so that the camera is toward the ground.
• Cables: yeah. A nightmare. The best we've done so far is Velcro at a fixed position on the side of ra. Still thinking...
• Lose the finder; plate solve.

Cheers and HTH

Edited May 7, 2022 by alacant

[Jim Smith]

7 minutes ago, spillage said:

@Jim Smith

How is the balance of the scope when you release the clutches? I would route the cables from the scope down the dec and along the ra if you have enough cable to allow dec full movement. Not sure if you are aware how much rotating the scope in the tubes also helps with balance.

 

*Might be worth loosing the telrad and using plate solving instead.

I took the photo after loosening the clutches and balancing in RA and DEC. It balanced just fine as shown. 

I probably need longer USB cables. Are there special light, flexible ones that can be used?

Good point about rotating the scope. I can see how balance would change if you did.

I like the Telrad for "sanity" checking that the scope is pointing in about the right direction!

Once I have autoguiding working I'm going to take a look at dithering...plate solving could be after that...

[barbulo]

 

1 hour ago, Jim Smith said:

Since fitting the Telrad finder, I had a lot of trouble

57 minutes ago, Jim Smith said:

I like the Telrad for "sanity" checking that the scope is pointing in about the right direction!

Why would you need a finder having the capability to plate solve? Moreover, if it hampers the balance…. (I’d just get rid of it). 

[Jim Smith]

14 minutes ago, barbulo said:

Why would you need a finder having the capability to plate solve?

At the moment I have not yet researched plate solving. I do not know what I need or how it would work with other software. But fear not, it is on my list of things to do!

[barbulo]

1 hour ago, Jim Smith said:

I do not know what I need or how it would work with other software.

Your setup and imaging software such as APT, N.I.N.A., Ekos…

[Jim Smith]

7 hours ago, alacant said:

Rotate the whole tube in the rings ~180º so that the camera is toward the ground.

Done! Yes, that is a better arrangement for balance and cable runs. Thanks.

[Pitch Black Skies]

7 hours ago, alacant said:

Fit a rigid rail to tie the top of rings

Can they be bought or is something we need to do ourselves?

[Pitch Black Skies]

7 hours ago, Jim Smith said:

Here is my new set-up with the longer, Losmandy dovetail bar. (Since fitting the Telrad finder, I had a lot of trouble finding good positions for the tube rings that also allowed me to get balance with the original Vixen dovetail with it's screwheads poking out the bottom. Also, it was green!) This should be much more stable and might help with my autoguiding problems. I also need to think about organising the cables a bit better. It's too easy for them to catch and rub at the moment.

You can power your guide cam with a very short cable running from your main cam. One less cable to worry about snagging.

[Clarkey]

8 minutes ago, Pitch Black Skies said:

Can they be bought or is something we need to do ourselves?

I have used a bit of box section aluminium along the top before now. Works fine and a lot cheaper than astro kit.

[alacant]

48 minutes ago, Pitch Black Skies said:

Can they be bought

An aluminium box section is fine, as is a narrow dovetail plate. So long as it's rigid. Whatever you have lying around. Go for functionality rather than good looks.

Edited May 7, 2022 by alacant

[Jim Smith]

15 minutes ago, Pitch Black Skies said:

You can power your guide cam with a very short cable running from your main cam

??? My guide cam doesn't have a separate power cable.

[Jim Smith]

2 minutes ago, Jim Smith said:

??? My guide cam doesn't have a separate power cable.

Or does the main camera act like a USB hub?

[Pitch Black Skies]

2 minutes ago, Jim Smith said:

??? My guide cam doesn't have a separate power cable.

Hi, I mean instead of the usb going from the guide cam to the laptop, you can just route a usb from the guide cam to the main cam.

[barbulo]

2 minutes ago, Jim Smith said:

??? My guide cam doesn't have a separate power cable.

The only cable. Your imaging cam is a two-port USB hub. 

[Jim Smith]

5 minutes ago, Pitch Black Skies said:

you can just route a usb from the guide cam to the main cam.

I wonder if I could route my EQDIR cable from the mount to my main camera too?

[Pitch Black Skies]

22 minutes ago, Jim Smith said:

I wonder if I could route my EQDIR cable from the mount to my main camera too?

Unfortunately not, that has to go from the mount to a computer.

If you had the ASIair you could route the EQDIR from the mount to that. It's a really tidy set up.