ed80 or 100

[rolls05 (Roland)]

Howdy. After taking advise and checking out hundreds of posts and pics Ive settled on a heq5 goto mount. I'm happy to go ed80 or ed100. I'm gonna be wanting nebulas and suchlike but also big chunks of milkyway. Not so much planets. Advise would be much appreciated.

[cometcatcher (Kevin)]

To take images with you mean? Either would do. The ED100 would usually have a bit longer focal length and therefore magnification. But either are good for wide fields.

[loki78 (Jon)]

Either will do you really. Have a look on

http://www.12dstring.me.uk/fov.php

It will give you an idea of the field of view of various scope/camera combinations. You can also factor in barlows/focal reducers. There is a database of popular targets to give you examples from. So have a look at the ones you would be typically chasing and marry them up with the scope focal length (in your case either ed80's or 100's) and see what your preference is

[loki78 (Jon)]

Sorry, wasn't sure if you want visual or imaging so,

http://www.12dstring.me.uk/foveyepiece.php

is the visual version with scope/eyepiece combos rather than a camera.

[LewisM]

ED100 is good. ED80 to me is BETTER. The visual and the photographic quality of an ED80 was just that bit better IMHO than the ED100 I had. The ED100 was good - the ED80 is SUPERB (and the only Skywatcher scope I have kept out of quite a few)

[rolls05 (Roland)]

lovely stuff. Yes,photography is what i'm after primarily. Thats a good site there Jon. Thanks for that. Thats kinda what I've needed all this time. Lewis,thanks .After checking that site and noticing pics of members who have either scope ,it seems to me that the fov is similar but the ed80 pics do seem sharper,brighter somehow. Fair comment? 'cause the 80 would do me if only for the price. Way cheaper than the 100. Would the 80 be kinder on the tracking side of things? I wont be wanting (affording) guiding at all. Cheers.

[cometcatcher (Kevin)]

Usually the ED100's focal length will be slightly longer, so tracking will be easier with the ED80. Check the specs though because every scope is different. The shorter the focal length, the less critical tracking will be.

If you do get a refractor you may also need to factor in a field flattener. This will also affect the focal length as some have 0.8 reduction.

[rolls05 (Roland)]

Thanks Kevin. The 80 is 600mm (f7.5) The 100 is 900mm (f9) ; Ok ,now I get it. Think of the scopes as zoom lenses for my camera, longer the zoom harder to track and stop stars from ob-longing as it were. Yes, ed80 is looking good. I can get the ed80 heq5 combo from Aus. Hundreds cheaper than here in NZ. So looking forward to it. Thanks again guys.