Uploaded 9-Nov-09
Taken 3-Jul-09
Visitors 906

2 of 15 photos
Photo Info

Dimensions640 x 428
Original file size211 KB
Image typeJPEG
Color spacesRGB
Date taken3-Jul-09 11:45
Date modified3-Jul-09 11:45
Shooting Conditions

Camera modelNIKON D40X
Focal length20 mm
Focal length (35mm)30 mm
Max lens aperturef/3.6
Exposure1/1250 at f/8
FlashNot fired
Exposure bias0 EV
Exposure modeAuto
Exposure prog.Aperture priority
ISO speedISO 400
Metering modeCenter-weighted average
Digital zoom1x
7/2009 - Present (Short Focal Length)

7/2009 - Present (Short Focal Length)

This imaging setup shows both the main telescope (left), a Vixen ED80Sf, and the autoguiding telescope, an Orion ShortTube 80mm.

Attached to the guidescope (right) is the autoguider camera, a small CMOS device that is used to keep a guide star perfectly centered during long exposures.

I made the side-by-side mount myself from plate steel and a dovetail bar from Vixen. I also made the drawtube bracket on the guidescope to help secure it. If it moves, the resulting image suffers from flexure.

The main imaging camera is a Canon 40D modified DSLR. It was modified by Hap Griffin to remove the internal infrared filter thereby allowing better sensitivity to the red emission nebulae.

While it's difficult to see in this image, the mount shown is the SkyView Pro, but the actual setup uses a much beefier mount, the Orion Atlas EQ-G.

Vixen ED80Sf Telescope
Type: Apochromatic Refractor (APO)
Aperture: 80mm
Focal Length: 600mm
F#: f/7.5*

Orion ShortTube 80 Telescope
Type: Achromatic Refractor
Aperture: 80mm
Focal Length: 400mm
F#: f/5.0

* This scope is typically used with a 0.8x focal reducer making it image at f/6.0.

Orion StarShoot Autoguider
Type: Monochrome 1.3 MP CMOS Camera
Size: 6.66mm x 5.32mm
Resolution: 1280 x 1024
Interface: USB 2.0
Guide Port: ST-4