Guiding with KStars/Ekos/INDI

[Gina]

Been testing...  I can choose either the 1600 or the 174 for imaging.  Also for guiding and it grumbles if I choose the same camera for both 🤣

Edited February 1, 2020 by Gina

[Gina]

This is my indiserver command.

gina@rpi-wf:~$ indiserver -m 100 -vv indi_asi_ccd indi_asi_wheel indi_eqmod_telescope indi_rpibrd indi_rpifocus indi_asi_ccd_2

 

[wimvb]

I'm surprised the indi_asi_ccd_2 entry works, because this is not the name of the driver.

Here's my ekos profile:

As I wrote, I don't start the servers from command line, the ekos profile takes care of this. But I run Ekos locally on the sbc. You could try if this also works remote, with the drivers on the Pi, and Kstars on a laptop/Mac (set Host IP to your Raspberry Pi IP-address of course).

When I ran 2 sbc's, I had the imaging camera on one (called 'camrock'), and the guide camera on the other. I would start the drivers on the camera sbc with

indiserver -v indi_asi_ccd indi_asi_wheel

then I would start the mount/guider sbc with

indiserver - indi_eqmod_mount indi_asi_ccd "ZWO CCD ASI174MM-Cool"@camrock "ZWO EFW"@camrock

How to do this is described on the INDI site.

[Gina]

Hmmm...  The ASI 174MM gives an image with very small exposure and the lens stopped down to f16 but all I can get from the ASI 120MC-S is a plain white image.  This applies in both the imaging and guiding sections.  I bought the ASI 174MM for Ha solar imaging but I won't be solar imaging when DSO imaging so I could use the 174 ad a guide camera.

[wimvb]

Have you checked the gain settings for either camera? It's in the INDI control panel

[wimvb]

6 minutes ago, Gina said:

so I could use the 174 ad a guide camera.

Not with the 55 mm f/1.8 lens, I hope? This would give you an even coarser pixelscale. The ASI174 has 5.86 um pixels, vs 3.75 um for the ASI120.

[Gina]

The gain on the ASI 120 was 50, I've changed it to 10 and have an image.

[Gina]

Took the "_2" off the ASI_CCD driver and the asi120MC-S no longer works.  Though it is shown in the INDI Control Panel - KStars.  Strange!!

Edited February 1, 2020 by Gina

[wimvb]

Better put the '_2' back again, then. 😉

If there are multiple ftdi chips competing in indi, it's usual to do usb port mapping. I wonder if this works here as well. Just a thought.

[Gina]

Image back again.  Gain 10, exposure 1s, 55mm lens, aperture f16, view through window roughly south, light fading.

[Gina]

Here are 3 photos of different lenses on the ASI 120MC-S camera attached to a Losmandy-style dovetail bar with printed bracket.  55mm, 135mm and 200mm lenses.  To use the 200mm lens, it will need an extra bracket to hold the front of the lens to get sufficient rigidity.  Obviously the 55mm is lightest.

[wimvb]

With the guide camera hanging the way it does, you'll get differential flexure. The question is how much you can tolerate with your pixelscale. The 135 mm may be the best option. Can you add a support to that? 

[wimvb]

A thought; can you mount everything at 90 degrees to the plate? This will allow both imaging camera and guide camera to be on the plate. It would allow for better balance as well. 

[Gina]

16 minutes ago, wimvb said:

With the guide camera hanging the way it does, you'll get differential flexure. The question is how much you can tolerate with your pixelscale. The 135 mm may be the best option. Can you add a support to that? 

Yes, I can and already been thinking about it.  I made a mistake in my post though - that is a 105mm lens.  The 135mm is currently on the imaging rig out in the observatory.

[Gina]

20 minutes ago, wimvb said:

A thought; can you mount everything at 90 degrees to the plate? This will allow both imaging camera and guide camera to be on the plate. It would allow for better balance as well. 

Interesting thought.  Hadn't thought of it myself.  This would not work with the dual mounting bar that's currently on the EQ8 but could work directly on the EQ8.  I'll investigate.  Thanks.

[Gina]

Yes, I think this will work.  Imaging rigs on each end and guiding in the middle.  I have a Vivitar 400mm f3.5 lens which is lower quality than the Asahi Super Takumar 200mm f4 lenses and could be used for guiding.  I will need to modify the mounting brackets and reprint but that's no problem.

This shows one rig with 400mm lens and guider.

[Gina]

Brackets printed for the guider now printing the ones for the imaging rigs.

[Gina]

Printer is playing up - need to sort it out!  Ordered some M6 socket head screws which came today but the heads were oversize and won't fit into the dovetail!!  GRRRR!!!  😡😡

[Gina]

Ordered some "proper" M6 screws from ebay (GWR Fasteners - which I've used before) which should arrive Wednesday or Thursday.  Meanwhile, if I'm ready with everything else, I have M5 bolts and nuts.  I need to build another control unit plus casing and print focuser parts for other size lenses so still plenty to do yet.

Edited February 3, 2020 by Gina

[Gina]

On 01/02/2020 at 10:02, wimvb said:

Pixelscale 206*3.75/55 = 14"/pixel, roughly. I would say that you are very undersampled. I don't think phd will like that star profile. You could try to cheat phd by giving the guidelens a small defocus.

With a minmo of 0.2 in phd, you'll be looking at an rms of 3" at least. The imaging camera @200 mm will have a pixelscale of 3.9"/pixel. About the expected rms. With a slight defocus and a minmo less than 0.2, it just might work. Try it, and share the results here. I'm very interested to see if it works. 

@wimvb - I don't plan to use the 55mm lens for guiding so won't have the information as to whether it would work.  Could make up a test rig to see, if you or anyone else is interested.  Seems to make sense to start with something more likely to work well though.

Edited February 3, 2020 by Gina

[wimvb]

3 hours ago, Gina said:

Could make up a test rig to see, if you or anyone else is interested.

Thanks, but there's no need to go through that trouble for me. What fl do you intend to use? 

[Gina]

200mm for guiding and various lenses for imaging up to 200mm.  May try a pair of 55mm f1.8 for imaging again - got poor results before.  Otherwise, 105mm f2.8 and 200mm f4.

[Gina]

The ASI120MC-S seems to have an intermittent fault going from normal image to this :-

The wavy line is on the ground/trees to sky interface.

I also have an ASI 178MC camera which seems to work.  Focus is very critical even stopped down.

[Gina]

I thought of a possible problem with guiding.  Thought it might stop while the main image was downloading but it seems that knro has fixed this by giving guiding image download priority.  That's from KStars version 3.0.0.  I have 3.3.1.

Edited February 4, 2020 by Gina

[TerryMcK]

I've been playing around with the PI4, Astroberry, PHD2, KStars and of course Ekos for a couple of days. I found I had to have PHD2 loaded first but not connected to guidecam/mount.

Then I fired up KStars and clicked onto Ekos I could start all the services ok - click connect and all devices were connected. Then I found that PHD2 had automatically connected to the guide camera and mount (which I had preconfigured). Iassume Ekos does this automatically. As we haven't had any cloudless nights in these here parts (looking forward to Tuesday night 04/02/2020 though) I've taken a few darks while the guider was looping (both ASI cameras BTW) and found downloads worked fine without interrupting the guider.

I used to occasionally get camera disconnects on Windows for PHD2 with ZWO gear while imaging (download time outs). Then I found the solution was to use native driver for the guide camera and ASCOM for the capture software (APT on Windows).

Not sure if INDI has the same problems but not come across anything - yet...