lavoisier Posted March 12, 2011 Share Posted March 12, 2011 HiI have a 127mm refractor and a 200mm reflector and was just wondering which objects would be bset for each scope? Just so I can get the most out of each and plan my observing a bit, if these skies ever clear!ThanksPaul Link to comment Share on other sites More sharing options...
rowan46 Posted March 12, 2011 Share Posted March 12, 2011 it depends on your focal ratio fast scopes give wider views and thus are better for dso's slower scopes have a narrower fov take magnification better and consequently are better at planetary observing. Link to comment Share on other sites More sharing options...
lavoisier Posted March 12, 2011 Author Share Posted March 12, 2011 Sorry a bit lost there. Both are f1000mm. So does that give me an F5 for the reflector(Explorer 200P) and about F8 for my Evostar refractor?ThanksPaul Link to comment Share on other sites More sharing options...
GazOC Posted March 12, 2011 Share Posted March 12, 2011 The 127mm refractor will be hard pressed to beat the 200mm reflector on any object. Of course you don't have to collimate it or wait for it to cool down like you would with the reflector. Link to comment Share on other sites More sharing options...
dmahon Posted March 12, 2011 Share Posted March 12, 2011 The wideness of the view depends on the focal length of the scope - if the faster scope has a longer focal length (because it also has a larger aperture) then the slower scope would give a wider field of view. Link to comment Share on other sites More sharing options...
lavoisier Posted March 12, 2011 Author Share Posted March 12, 2011 I thought perhaps the refractor would have been more for lunar and planetary observing. Thanks to you all for taking the time and trouble to post. Paul Link to comment Share on other sites More sharing options...
GazOC Posted March 12, 2011 Share Posted March 12, 2011 I thought perhaps the refractor would have been more for lunar and planetary observing. Thanks to you all for taking the time and trouble to post. PaulI think the gap inbetween the 2 scopes will be less when observing planets rather than DSOs. Link to comment Share on other sites More sharing options...
Abb Posted March 13, 2011 Share Posted March 13, 2011 I prefer my Celestron 120 Omni refractor mostly for planet and lunar observations and my 8" Skywatcher Dob for DSO's although I have used them both for everything. I find everything in my Dob to be flatter than in the refractor. Link to comment Share on other sites More sharing options...
ollypenrice Posted March 13, 2011 Share Posted March 13, 2011 If the 127 is an apo you might prefer the planets in that, but since they share a focal length then they don't really complement each other at all well. Both do the same thing but the Newt has more aperture. If collimated it should win all round. Time to swap one of them for something very different, perhaps??To confirm, f ratio has no bearing on field of view. That is governed by focal length. At the same focal length the brightness will be higher at a fast f ratio because there is more more aperture.Olly Link to comment Share on other sites More sharing options...
lavoisier Posted March 13, 2011 Author Share Posted March 13, 2011 Hmmmmmmmmm...... food for thought. Thanks OllyPaul Link to comment Share on other sites More sharing options...
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