Thoughts on which imaging rigs to concentrate on

[Gina]

Flame and Horse's Head in Orion with 200mm f4 lens and 400mm f5 Esprit 80ED scope.

Edited January 31, 2020 by Gina

[Gina]

M42 will fit nicely in the FoV of the Esprit.

[Gina]

Returning to the Heart and Soul, while these didn't fare well as a pair with the dual lenses, they do work as separate objects in the 200mm lens and Esprit 400mm scope.  The Esprit can be "twinned" with an ST80 for a dual imaging rig.

Edited January 31, 2020 by Gina

[Gina]

With the camera turned 70° rather than 90° the framing for the Heart Nebula is much better.

[Gina]

Now I want to sort out how to arrange dual imaging rigs and guiding.

With telescopes it's clear - one on each mount of the dual mounting bar.  Though I have just the one Esprit 80ED, the humble ST80 is same focal length and an achromatic scope is alright for NB with the very narrow wavebands, so an ST80 is adequate second imager.  I also have a pair of Evostar ED80s both with focal reducer/flattener.  The FL becomes 510mm and f6.37.  In either case one scope can have an OAG for guiding.

Edited January 31, 2020 by Gina

[Gina]

With widefield imaging rigs it's not so clear-cut.  My earlier thought was to make a double bracket to take two cameras side by side but now I have the dual mounting bar there's a simpler option.  Copy the current WF imaging rig and put one on each mount.  One can use the 8 position ZWO filter wheel and the other the ZWO EFWmini with 5 positions. 

There then remains the question of guiding.  Seems an OAG is not practical with lenses.  Reason is that the back-focus of these vintage film SLR lenses is 45mm whereas that of the FF is 55mm.  This means the distance from OAG prism to sensor is only 30mm rather than 40mm and the guide camera can't be got close enough to focus.

Edited January 31, 2020 by Gina

[Mick H]

Gina I think a triple rig would be ideal 😉

Watch as moths fly out of Gina's purse

Edited January 31, 2020 by Mick H

[Gina]

Another rethink on arrangement for dual imaging with guiding, resulting from a suggestion from Wim, for which I'm grateful.

I now plan to use a 15" Losmandy-style dovetail bar at 90 degrees to normal with an imaging rig at each ends and guider in the middle.  This photo shows the arrangement though with just one imaging rig ATM.

Edited February 2, 2020 by Gina

[Davey-T]

Had similar but larger scale on the iEQ45 once, helps with balancing as  you can slide the bar sideways.

Dave

 

[Gina]

Since Ekos can only handle one imaging system currently, separate instances of KStars/Ekos are needed to handle dual imaging.  It does handle a separate camera for guiding.  Each imaging camera will have it's own RPi for capture and focussing the lens.  These will have different Computer Names for identification from KStars/Ekos.  Each will have it's own Ethernet connection from an Ethernet switch on the pier.  One RPi unit will just connect to camera and focuser whilst the other will also connect to the mount and guide camera.  It isn't considered necessary to provide remote focussing for the guide system.

My experience with dew heaters has shown that (at least in winter) I never run with the dew heater turned off so I see no need to have remote dew heater control.  If I don't want dew heater control, it will simplify both hardware and software.  The current WF rig does have this control but the second RPi and HAT can do without it.  I can just ignore the dew heater control on the current RPi control unit and connect the dew heater directly to the 13.8v supply.  In other words all three dew heater would be connected to the main supply via a fuse and maybe a toggle switch (or I could simply remove the fuse if dew heaters are not needed).

The photos below show the RPi plus HAT (Hardware Attached on Top) which was originally designed for use with the Esprit 80ED Pro telescope but now used with the WF rig.

[Gina]

Since Ekos can only handle one imaging system currently, separate instances of KStars/Ekos are needed to handle dual imaging.  It does handle a separate camera for guiding.  Each imaging camera will have it's own RPi for capture and focussing the lens.  These will have different Computer Names for identification from KStars/Ekos.  Each will have it's own Ethernet connection from an Ethernet switch on the pier.  One RPi unit will just connect to camera and focuser whilst the other will also connect to the mount and guide camera.  It isn't considered necessary to provide remote focussing for the guide system.

My experience with dew heaters has shown that (at least in winter) I never run with the dew heater turned off so I see no need to have remote dew heater control.  If I don't want dew heater control, it will simplify both hardware and software.  The current WF rig does have this control but the second RPi and HAT can do without it.  I can just ignore the dew heater control on the current RPi control unit and connect the dew heater directly to the 13.8v supply.  In other words all three dew heater would be connected to the main supply via a fuse and maybe a toggle switch (or I could simply remove the fuse if dew heaters are not needed).

The photos below show the RPi plus HAT (Hardware Attached on Top) which was originally designed for use with the Esprit 80ED Pro telescope but now used with the WF rig.

Edited February 4, 2020 by Gina

[Gina]

Seems to be an intermittent problem with the ASI120MC-S that I'm using for guiding.  It shows as changing between a normal image and this

The rig is pointing southwards to a far hill with trees and the wiggly line is where the land/trees meet the sky.

Edited February 4, 2020 by Gina

[wimvb]

1 hour ago, Gina said:

Since Ekos can only handle one imaging system currently, separate instances of KStars/Ekos are needed to handle dual imaging.  It does handle a separate camera for guiding.

Do you run ekos on the Pi, or on a laptop/pc? Whatever you use, you can control the other camera from pixinsight. Just connect to the remote pi, and use the ccd process. It's fairly straightforward. 

[wimvb]

1 hour ago, Gina said:

Seems to be an intermittent problem with the ASI120MC-S that I'm using for guiding.  It shows as changing between a normal image and this

The rig is pointing southwards to a far hill with trees and the wiggly line is where the land/trees meet the sky.

Strange. Could it be thrown off by the overall brightness? How does it perform when it's darker? 

[Gina]

3 minutes ago, wimvb said:

Do you run ekos on the Pi, or on a laptop/pc? Whatever you use, you can control the other camera from pixinsight. Just connect to the remote pi, and use the ccd process. It's fairly straightforward. 

I run Ekos on my Linux Mint tower indoors.  I have been on the INDI forum and got info direct from the author.  I want to use Ekos for autofocus and plate solving etc. 

[Gina]

6 minutes ago, wimvb said:

Strange. Could it be thrown off by the overall brightness? How does it perform when it's darker? 

I don't know how it performs when it's darker as I've only been testing for an hour or so.  Exposure does seem to be very critical.

Edited February 4, 2020 by Gina

[wimvb]

Ok. Pixinsight can do platesolving of course, but not autofocus. It seems that development of the INDI modules in PI has stalled. 

[Gina]

I have been investigating connections as these are a common cause of intermittent faults.  Compared the USB3 input port on the ASI16000 camera with that on the ASi120.

 

 

[stash_old]

As far as I am aware you can Virtual Linux on the same Mint Tower - subject to memory and processor speeds and run either Ekos/Kstars or CCDciel in the virtual set up. Will still need 2 RPI running Indiserver.

OR

YOU MIGHT just be able to run CCDCIEL + Ekos on the Tower (No virtualisation needed) and have 2 RPI running Indiserver.  One Indiserver would run Mount,guiding,platesolving,camera A,focusing while the other would just run Mount simulator , Camera B and Focusing.  You just point Ekos and CCDCIEL to different Indiserver IP addresses.  This should work as I think the Indiserver  config files are held on the Indiserver computer (i.e. not the tower).  Thats the theory 🙂

[DaveS]

Urk, that doesn't look good. I had problems with a SX FW some years ago that turned out to be a missing centre block, though the contacts were still there. Sent it off to SX for repair and everything was OK afterwards.

[JamesF]

2 hours ago, Gina said:

 

That doesn't look great

I wouldn't have thought it would be too hard to replace though?

James

[Gina]

I'll take a look tomorrow.

[wimvb]

3 hours ago, stash_old said:

Will still need 2 RPI running Indiserver.

 

3 hours ago, stash_old said:

One Indiserver would run Mount,guiding,platesolving,camera A,focusing while the other would just run Mount simulator , Camera B and Focusing

Is this really necessary? Indi is distributed, ie N x M solution with any number of servers and any number of clients. I haven't tested this, but I wouldn't be surprised if only one rpi is needed.

Also, check this link

https://indilib.org/develop/developer-manual/100-3rd-party-drivers.html

Edited February 4, 2020 by wimvb

[stash_old]

3 hours ago, wimvb said:

 

Is this really necessary? Indi is distributed, ie N x M solution with any number of servers and any number of clients. I haven't tested this, but I wouldn't be surprised if only one rpi is needed.

Also, check this link

https://indilib.org/develop/developer-manual/100-3rd-party-drivers.html

Gina said "Since Ekos can only handle one imaging system currently, separate instances of KStars/Ekos are needed to handle dual imaging.  It does handle a separate camera for guiding.  Each imaging camera will have it's own RPi for capture and focussing the lens." and I concur that if you want to run 2 concurrent imaging camera's (i.e. NOT 1 imaging and 1 guiding which is ok) it is my understanding that is not possible at the moment because of Ekos !- perhaps  @RadekK could confirm or deny this !

You can as you point out run many Indiservers in a "Chain" but there will be one master and the rest will be slaves as I understand it - I have done "chaining" using multiple PI's and this works. In effect Ekos thinks its talking to one Server as I understand the chaining process.

Ok the master server can contain many devices and Kstars/Ekos has a profile so the 2 Kstars/ekos would have different devices defined in the active profile.   The following mentions this and Gina was part of the discussion and I presume had further PM's with the Dev's.

https://indilib.org/forum/ccds-dslrs/4256-multiple-imaging-camera-s.html 

Easy test Gina could run 2 Ekos/Kstars Plus 1 Indiserver with all the devices set up  🙂 

Dont know if anyone has done it it yet

 

 

[stash_old]

Dont know if this helps or not but Gina did you read this thread ? https://indilib.org/forum/ccds-dslrs/3255-using-3-cameras-at-once.html?start=12 - Bet you have 🙂