5se Vs 8 inch Dob.

[Theninjagecko]

Ignore the tracking of the 5se.

I believe the extra size of the dob would allow higher mag to see planets/moon as good if not better than the nexstar 5se + is fairly good for DSO's too.

If both scopes had the same size mirror then obviously its chalk and cheese but I believe the larger dob should out perform a 5se.

What are your thoughts?

[Kai]

What is the Focal Ratio of the Dob ??

[Theninjagecko]

What is the Focal Ratio of the Dob ??

Lets say F5

[Theninjagecko]

I think they might even be even stevens for planetary, but then you got the extra capability of the dob for dso's, so all in all, the dob should be the winner.

[Kai]

Then i would say the 5se would be better on Planets and the moon because of its native F10 thus nullifying the extra size of the Dob.

imo thats the reason that most plantery imagers use SCT's

[Kai]

If you want Dso's the the Dob will win , If you want both then go for a 8 inch SCT and get a Focal Reducer

[Theninjagecko]

Then i would say the 5se would be better on Planets and the moon because of its native F10 thus nullifying the extra size of the Dob.

imo thats the reason that most plantery imagers use SCT's

I thought it was because they are smaller and easier to mount ?

Been discussing this with my friend, I just don't see how the F10 of a 5 inch mirror would nullify a 8 inch f5 the 5 just doesn't collect enough light to be using such hi mag.

by his, and your logic, an 8se would be better than a 12 inch newt/dob for planets.

I've only seen C14's image as well as a 12 inch newt for planets.

What sparked this thread was me telling him my skywatcher 8 inch dob blew my mak 127, that sparked him off saying "i got what i paid for". I replied that celestron, meade and skywatcher arnt that far apart, orion stands out with the quality of the optics.

He also said "but not in so many words" than a etx 125 is better and worth the 2x price tag of the mak 127, but im yet to see an image from one to even come close to a mak 127 :\

[Theninjagecko]

If you want Dso's the the Dob will win , If you want both then go for a 8 inch SCT and get a Focal Reducer

then it wont pic up as much detail because of the smaller mirror.

[Theninjagecko]

its a 5sct/mak vs 8 newt/dob remember. not an 8 vs 8, for the price of an 8se you can get a larger newt/dob.

[GazOC]

Then i would say the 5se would be better on Planets and the moon because of its native F10 thus nullifying the extra size of the Dob.

imo thats the reason that most plantery imagers use SCT's

Got to disagree mate, other things being equal the bigger mirror will resolve more detail (conditions permitting). The focal ratio of the 5se does not offset the aperture of the 8" Dob.

Planetary magers like SCTs because they are compact and give good native image scale being f10 but the actual effect on the quality of views the scope gives from being f10 isnt the consideration.

[John]

I've owned a couple of 8" dobs (Revelation and Skywatcher) and an 8" SCT (Celestron). I liked them all but the views through the dobs were just as good as those through the SCT on a variety of objects and at times just a little better I thought - possibly due to the smaller central obstruction that the F/6 dobs had.

I've also owned a 5" SCT (Celestron again) which was great for it's compact size but could not really compete with the 8" aperture scopes in any department.

John

[Rob]

Seeing has a big role here.. larger scopes WILL suffer more if the seeing is bad. Your best bet for great planet views would be an ED100 / ED120. The bigger mirror will win hands down on DSO work. Seeing also has less impact on a 4" refractor.

Rob