Dual imaging

[LewisM]

OK, crazy idea for the day - just not sure if it will work computer wise...

I have 2 imaging scopes - one an f/5.6 refractor system using an ST-2000XM CCD and an ASI120MM guidecam. The other is an f/5 refractor using a DSLR. Mounted side by side on a goto mount.

So, can I run simultaneously say APT for the DSLR and MaxIM for the CCD for data acquisition, and then PHD2 for guiding...or is there going to be weird conflicts regarding downloads and data management trying to run all this?

EDIT: if I use the shutter-sensor pause (open shutter, but not start sensor until vibration stops) function to coincide with the download of the CCD it should work, provided I use the same length subs etc I would assume?

[glend (Glen)]

I don't see a problem other than ensuring neither capture app is trying to control the mount, ie no dithering. Let PHD2 do everything as far as guiding is concerned. Make sure there is no automatic connection between the apps and guiding. The issues will probably have more to do with laptop resources, including port availability, and hub sharing. I would imagine problems if both apps were trying to download and save at the same time. If you were running two separate laptops you would be ok i think. I run into issues with my guide camera and imaging camera conflicting unless i start the imaging camera first so that it gets the correct profile. A little HP Stream should be able to run APT, or BYEOS, ok.
Maybe a little Stick PC could be used for the DSLR with a second monitor. Interesting challenge.

[Atmos (Colin)]

If all three programs are running completely independently of one another there should be no problems save your computer being able to handle images being downloaded from all three at once. You can test this pretty easily though.
Have the DSLR and ST-2000XM taking bias frames while the ASI120MM is taking 1s exposures. If all three can run inside without the computer having an attack you should have no issues outside when downloads are less frequent.

[traveller (Bo)]

I have tried something similar Lewis,
I ran Maxim DL for my old CCD with PHD, EQMOD and Stellarium, while also doing widefield with my DSLR on a sky tracker through the same laptop using Backyard EOS.
Managed to get a few frames but problems started when both Maxim DL and BYE wanted to write to the same laptop at the same time or when one is writing and the other is attempting to write. Basically the laptop said No! and you will end up losing that frame or having programs crash, so back to square one.
One possible solution (which I haven't tried) is to write to different hard drives (as opposed to different folders in the same HDD) if you have dual HDD on your computer.
Good luck!
Bo

[alocky (Andrew lockwood)]

Hi Lewis,
I tried something similar, but gave up on it. I piggybacked an FSQ with a DSLR onto a 10" Newt with a mono ccd and off-axis guiding. The DSLR was being driven by an intervalometer to avoid USB or drive issues. Two reasons I gave up - the flexure in the system that the OAG perfectly guided out no showed up in the yak. Problem 2, every sub through the ccd that coincided with the DSLR shutter activating was ruined.
At shorter fl and with an independent guide scope it should work, but you can always bench test the sw and camera combination during the day.
Cheers
Andrew.

[Octane (Humayun)]

There be dragons.

H

[Slawomir (Suavi)]

It looks like Sara Wager is using a dual imaging platform: http://www.swagastro.com/dual-imaging-set-up.html

[Camelopardalis (Dunk)]

APT can cope with multiple cameras - check the user guide.

Essentially, you run 2 instances and there are settings for pausing both plans while dithering.

[LewisM]

Thanks Dunk - that is why I chose APT.

Having said that, never had good success with it and a CCD for some odd reason - unless the newer versions fixed this (haven't updated mine in about a year!)

[Camelopardalis (Dunk)]

Apart from an initial ZWO driver issue, I've not had a problem with it and my ASI1600 over 100+GB of acquisition....

[lazjen (Chris)]

Why limit yourself to dual imaging? Get all those scopes up and running collecting data at the same time.

[LewisM]

Originally Posted by Camelopardalis

Apart from an initial ZWO driver issue, I've not had a problem with it and my ASI1600 over 100+GB of acquisition....

Yeah, I know the ZWO frustration all too well! Once sorted though, it's smooth sailing.

Not as bad as the QHY drivers - never got a single QHY to work on my XP, Win 7 or Win 10 machines. EVER. It kept conflicting with the Atik drivers.

[Camelopardalis (Dunk)]

Originally Posted by LewisM

Yeah, I know the ZWO frustration all too well! Once sorted though, it's smooth sailing.

Not as bad as the QHY drivers - never got a single QHY to work on my XP, Win 7 or Win 10 machines. EVER. It kept conflicting with the Atik drivers.

Yeah I had all kinds of fun back in the day with my QHY, although they're putting out some tempting cooled cameras these days...MUST RESIST!!!

[tlgerdes (Trevor)]

I'm with H, it's like spinning plates on poles, with one hand tied. It​ can be done, but one wrong move and it gets messy quickly.

[Logieberra (Logan)]

Re SkyX, I'm quite sure that you can open two "instances" for this kind of setup, with different settings (saved) for each. I'm in the same boat - wanting to run RC (Atik) and FSQ (6D) at same time. TBc.

[JA]

Ever since reading of the DragonFly telescope array, the use of multiple telescopes has always taken my imagination - Well to at least 2 identical cameras for now, but still trying for a 2nd identical lens. Just missed one on ebay ....

My thoughts in relation to the associated software issues had always been separate laptops for data collection/download should always work. Although possibly 2 instances of the camera control/data collection program on one laptop might also work (DigiCam Control / Nikon ??). Ideally downloading in to the same folder, but if that's an issue use separate folders and combine them later (after imaging session). Using only 1 mount obviously only 1 program should control the motion if guided.

Best
JA

[PRejto (Peter)]

I spent nearly 5 years "perfecting" my dual scope setup; a TEC180 and TEC140 on an MEII. It is a can of worms but can give a satisfying result for sure. There are many problems!

1. Synchronizing exposures to allow for dithering. (http://astro.neutral.org/software/mu...t-TheSkyX.html)
2. Focusing two cameras.
3. pointing both scopes.
4. Obtaining similar FOV and resolution.
5. Differential flexure between the scopes (an unavoidable consideration!)
6. Automation (semi)

I solved all of these including DF by using AO on the second scope (without mount guide corrections being sent). Thus, TheSkyX provided basic guiding and dithering and the AO on camera #2 eliminated DF. I had special software written for me (available!) that synchronizes the cameras, sends filter change info, and automates the SX-AO to reset and continue between images. All of this is controlable using CCDAP5 in a normal fashion. Scope #2 is unseen by CCDAP5 but works in synchrony.

Most of my posts at Astrobin were taken with this setup:

https://www.astrobin.com/users/prejto/

My setup was the cover feature a few months back in Astronomy Technology. I'm happy to send a reprint to anyone interested. Just drop me an email to: prejto at oberlin.edu

Peter

[graham.hobart (Graham stevens)]

on Saturday I had the babyQ with FLI and OAG running through maxim, guiding the lodestar on PHD. Meanwhile I had cooled DSLR on APT with the FS 60 and on Nebulosity had my QHY8pro with camera lens doing its thing. I have also run two DSLRs with different instances of APT before. If you watch the cables and stagger down loads it seems ok.
In my view its maximising sky time as I only seem to get out once a month now.

[stefang (Stefan)]

There are a couple of options now of syncing more than 1 camera during imaging runs.

APT - AstroPhotography Tool - 18.70 EURO http://www.ideiki.com/astro/
Multiple Camera Sync in Maxim DL £50 (uses a Slave / Master setup) - http://astro.neutral.org/software/mu...ync-maxim.html

Sync'ing to ensure dithering occurs when the other camera is not taking an exposure is key. Its a difficult pipeline to get working, but when you do its WideField / Narrow Field bliss.

stefan

[Terry B]

I do similar all the time. I have one scope with the CCD taking pics for photometry and the other one with the spectrograph taking simultaneous spectra.
I do use 2 computers though to stop conflicts. The second one is a $300 lappy and is perfectly capable of running 1 camera and guider.