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Use of Televue 60mm APO as an astrograph

Started by ivanong, 02/05/2005 07:15PM
Posted 02/05/2005 07:15PM Opening Post
Recently I acquired a Televue 60mm APO. I have enjoyed many nights of grab-'n'-go observing with this little scope and have been very impressed with the optics. For example, Rigel is a very easy split with a 9mm Nagler, clean and very pleasing. Saturn at high powers yields nice views of Cassini's Division and The main Southern Equatorial belt with hint of minor coloration of other belts. There is a crispness to the optics that makes you fall in love with this little scope.

Yesterday, I was in the Blue Ridge Mountains and decided to try the Perseus Double Cluster with this scope. I used a T-ring 1.25" adapter and my Canon 20D. Exposure was 4 min, manually guided.
I wanted to evaluate whether this scope will be a nice 360mm wide field imager. Tonight I processed the images through photoshop and I am rather disappointed. Look at the obvious elongation of stars on the peripherals, I estimate 40-50% of imaged area is not acceptable. This cries out for a flattener but I doubt anyone makes one that can be used for this model. Maybe Borg adapters and Tak's 60C reducer/flattener?

The other thing that makes me hesitate about using this as an Astrograph is the lack of a rotating focurser like Takahashi's Camera Angle Adjuster. Framing a shot by loosening the 1.25" compression ring immediatley required refocusing through my laptop software, so that is not good as the routine gets old quickly. Once again I believe a Borg rotating focuser may be employed as they have a 1.25" adapter for that.

I would conclude that the Takahashi FS-60C is a much more suitable scope for imaging than this, but then that should be fairly obvious given the accessory support that Tak has.

The Televue was primarily designed as a grab and go visual scope, and it certainly lives up to its billing there. Another use may be for birding photography. The draw tube/helical focuser will make for rapid terrestial photography.

Clear Skies,
Ivan


Attached Image:

ivanong's attachment for post 22048
Posted 02/06/2005 08:14AM | Edited 02/06/2005 08:15AM #1
It's a nice shot nonetheless Ivan...
I can definitely see that a field flattener would be necessary for this scope, in order to take advantage of the full fov (imaging-wise)... but the contrast & detail are great already! (I wonder if anybody out there would have one compatible with your setup already...)


Thanks for sharing! wink

Ivan Gastaldo 8)
Coconut Creek, FL

Ivan's Observatory
Lat 26N 16' 48" Long 80W 10' 48"
[COLOR="Red"]Personal Website:[/COLOR] http://www.ivangastaldo.com

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