Due to a recent vertigo problem (inner ear issue, hopefully short-term) I am unable to bend over a scope or finderscope in the dark (without consequences); so I needed a solution that enables me to sit at my observatory workstation for alignment, initial image framing, etc. Why not just use the imaging camera, after all some imaging people don't even use a finderscope, well because of the field of view issues with my DSLR especially on my longer focal length scopes. Yes it could be done, but I find a finderscope easier.
So my solution was to adapt an Orion 70mm f4 Multi-Use scope for video capture, to be displayed on my laptop in a finderscope window. I bought an ASI034MC camera - very basic but high frame rate and a bit better than a usual webcam. The Orion scope has a focal length of 279mm, a helical focuser, and comes with a couple of adaptors to add length to the tube if neccesary. I initially tried using a 90 degree diagonal that I had on hand, but was unable to achieve infinity focus, so I went with a straight through arrangement with a 1.25" extension tube (actually the top section of an old barlow without the lense elements). With that setup I was able to achieve focus and do some initial daytime testing on distance objects.
I have attached some photos of the setup. I need to do some night time star testing to tune the focus precisely and workout the video settings for the application. ASI offers downloads of the drivers and the capture app, so I am using that initially. But if someone want to recommend a good video capture app that works with ASI high frame rate cameras then I will try those.
Glen,
I use an ol' Zuiko 200mm lens and an ATiK16 as an electronic finder.
I just use PHD to provide the image - KISS
It works well for me, maybe you can do the same with the WZO?
Yeah Ken, I have had it working through Metaguide, so that,'s an option, just run a second instance for the guide camera. The advantages of the guide apps are the crosshairs or reticle overlay. I've got Sharpcap as well., and PHD2 on the same laptop. I will try them out tonight if I can.
Thanks Dunk, yes I have that in mind at some point. I have been reading through the BYEOS info on setting up Astro Torilla but I would need to upgrade to the premium edition of BYEOS. That's probably the ulimate destination. However, my expereince with the Astro Torilla plate solver on Astrobin shows that for long focal length images it can fail to solve - simply the field is too narrow for it to find a solution (this is only a problem with my RC08 due to the small field of view, and particular target objects without good reference stars/objects in the field.)
For now I have got the video finderscope working last night and following the KISS principle, ran it through PHD2 to get a target rectile on screen.
You might be able to plate solve on your finder/ZWO combo with astrotortilla rather than the main camera. The only trick is to make sure everything is aligned precisely and stays that way...
I am going to test it once the weather clears!! Raining for the next week here.
I used to find it very helpful plate solving through my 50mm finder to get my main scope "in the ballpark" for final alignment and platesolving. That was with pinpoint and Maxim however. Definitely do-able.
Rob,
Yes, a good electronic finder is a tremendous aid.
AstroArt5 has done a good job Plate Solving some of my trial images with the 200mm/ATik16 set-up - good enough to get the target star onto (or very close to) the spectroscope slit.
Recommended.
Thanks Dunk, yes I have that in mind at some point. I have been reading through the BYEOS info on setting up Astro Torilla but I would need to upgrade to the premium edition of BYEOS. That's probably the ulimate destination. However, my expereince with the Astro Torilla plate solver on Astrobin shows that for long focal length images it can fail to solve - simply the field is too narrow for it to find a solution (this is only a problem with my RC08 due to the small field of view, and particular target objects without good reference stars/objects in the field.)
For now I have got the video finderscope working last night and following the KISS principle, ran it through PHD2 to get a target rectile on screen.
Glen, you don't need the BYE integration for Astro Tortilla to work, you can use many of these tools independently without paying extra. As I've mentioned before, I use APT and happen to use the built-in plate solving in that, but it also supports AT. APT is fully featured and more reasonably priced, and of course there is a free trial available.
I don't use a finder any more..I just stick the camera on the scope and use plate solving to nail my target. Saves a lot of time and effort, and no bending the neck into awkward positions
Dunk I have APT but I can't see any plate solving related function in the menu system. Are there different features in different version or license downloads? How do you get it to work?
I will try plate solving with Astro Torilla with an image from the findersope camera as a first step.
Thanks
Glen
The plate solving is in the Gear tab, called Pointcraft...you need to Connect Scope for it to be able to move the scope through ASCOM (although that's not required to solve an image you have captured). Check out the User Guide section XXVIII, it's practically idiot proof to set up. Be sure to input the correct focal length for your scope in the Tools tab.
Although I had tuned AstroTortilla for my different scopes, I find Pointcraft just works more reliably in practice.
Well, just tested the system and it works brilliantly! I have a QHY5l-ii mono attached to a ZWO finder scope (280mmFL) and AT plate solved with very few issues. I did have to set the exposure time to 5 sec for it to pick up enough targets (seemed to do best >12 stars). I was up an running in about 5 minutes and didn't look through the finder scope ONCE.
Goto's were very accurate but I did have my finder/QHY aligned perfectly with the camera, and checked this before running AT. What a great piece of software!
