Skywatcher Exloprer 190MN or Celestron Edge HD 8"?

[RobertI]

Hi all,

For around £1000 the 190MN looks like a really nice scope for both wide field imaging and visual. For another £300 the I could get the Celestron Edge HD 8" with a focal reducer.

I think the light gathering power would be similar as the Celestron has a large central obstruction.

Assuming I am not too concerned about portability is the Celestron worth the extra money?

I would use primarily for imaging with occasional visual.

Any comments appreciated.

[Gina]

To me the most interesting part is the processing - bringing out all the hidden detail and making a pretty picture of it.  I don't find the data collection all that enthralling though checking the the subs as they come in is quite interesting.  But I only check the first few usually though when there's a good clear dark night and I get going early I check every so often and watch that the guiding is going alright.  However, a lot of my imaging I do while I sleep leaving the gear to take care of itself and hoover up the photons.

As I've said before - I also get great pleasure from making and modifying my own equipment.

[Komet]

Hi all,

 the 190MN looks like a really nice scope for both wide field imaging 

The MN190 -  wide field? 

eh?

[ollypenrice]

Forget 'light gathering' for astrophotography. It isn't entirely meaningless but it needs to be seen in a rather complicated context involving focal ratio and pixel size. Just saying 'This scope has an extra inch' is not in the least bit indicative on its own.

You say you can get the Edge HD with reducer for an extra £300. Are you sure about this? The Edge HD needs Celestron's dedicated reducer which is pretty costly on its own. The old style flattener reducer is no good on the Edge, which already has a flat field.

The MN190, on form, is a stunning beast but it is just that, a beast. It's big, even for an NEQ6. Possible without doubt but not on all nights. Wind would be out of the question and setup is a serious business if you are not in a permanent base. It also needs to be sorted out. It will never be a plug and play scope. It has a bigger flat field image circle than the reduced Edge so what's your chip size?

A metre of focal length doesn't give you a wide field. This term is usually used for focal lengths below about 600mm, though there's no hard definition. If you are a beginner, wide field has lots of advantages, being easier to guide for a start. For this a small apo refractor is ideal. Ignore the 'light gathering' bit. I'd call this a reasonably deep M45 ad it came from 85mm of aperture. http://ollypenrice.smugmug.com/Other/Best-of-Les-Granges/i-WQXKB6Z/0/X3/M45%20COMPOSITE%20FL-X3.jpg

Olly

[Mr Bergman]

I can only agree with Olly; I have the 190MN with a NEQ6pro, which I transport and set up EVERY time skies permit. It´s doable, but it´s huge and works as a sail in wind:-) Hovewer, a great scope for imaging! 

[RobertI]

Thanks for the replies guys. I have to say despite being a visual astronomer for many years, it's taking me time to understand the significance of focal length/focal ratio/aperture when it comes to imaging. Olly, I understand you point about small APOs - I will carry on learning the art of imaging with my tiny APO refractor for now.