||Orion ED 80mm f/7.5 apochromat
600mm focal length
Weight 5 lbs 11 oz. (2.58 kg)
||Orion ST80 80mm f/5
400mm focal length
|Video finder Scope
||Mintron 13V1C 50mm f/2 Pentax lens
The Orion 80 ED refractor (5
lbs 11 oz.) is a good quality apochromat well suited to the Canon 350D camera. It
has very noticeable coma (i.e. field curvature) around the edge of field, however when
cropping a 1280 pixel-wide image from the centre of a picture the coma is hardly
noticeable. Images show minor color (blue) fringing, but usually this is hardly
- I use a William Optics x0.8 field flattener/reducer which greatly reduces the
coma at the edge of field, at the cost of some very minor distortion in the centre.
The reducer speeds up the scope to f/6 and reduces its focal length to about 480mm.
It also increases the field of view.
D Fields of View ( 22.2 x 14.8 mm chip)
|600 mm natural
|480 mm (x0.8)
The Orion 80ED has a 2" Crayford focuser which is sturdy and
nice to use. It doesn't have a 10:1 micro-focuser, but I found it easy to focus.
The Orion 80ED is being replaced by the new kid on the block - the Orion 80 f/6
EON telescope which from all accounts is a much better scope for imaging. It's
got less coma, shorter focal length and a microfocuser. I want one for Xmas.
The Orion Short Tube (ST) 80mm is a nice little scope for the
money (very cheap). As a guidescope it is okay, however the focuser tube is only
1.25" and has a little bit of yield/wobble in it. I wouldn't recommend it for
imaging with, but as a guidescope it is good. As a scope for kids it would beat most
similarly priced department store scopes.