4" Refractor or 5" Mak?

I have a problem! I want a second scope...I have the 80mm Stellarvue AT1010..but I want more aperture and some portability...thus, whatever I get will sit on a Unistar Mount....

I'm wondering if a 120mm Achromat will put up equally good images as a 127mm Mak? Both are the Orion scopes(i'm on a budget also). Which would you recommend?

I've also considered the Stellarvue 102 Achromat...but for 795.00, I figured I'd be better off with more aperture/less cost...

Any help would be super appreciated!!

I would go for the Mak since it will outperform an inexpensive 120mm achromat on the planets. Despite all the claims of reduced color views with minus violet filters, etc. an achromat that size won't match the Mak in planetary performance. Since you already have widefield covered you won't have to worry much about the long focal length of the Mak. It would also be easier on an alt azimuth mount like the Unistar (less of a lever arm and less adjusting to different eyepiece positions).

Joplin

Dan, I agree with you and Brian about narrow fields of view. I was only looking at the Mak out of desperation to save money(see my last post to Brian)...I think the narrow FOV will drive me crazy with the Mak.

As you'll see in my post to Brian, I had been planning on getting the 8" Reflector Eq setup...but figured i'd check into just getting a refractor or mak OTA and placing it on my Unistar Mount to save 2-300 bucks.

So far, my desire for aperture is winning out..but it doesn't hurt to make sure of other alternatives.

Robert, have you considered a 6 inch reflector on the unistar? It should probably handle the long tube 6 incher from Orion, and it should save you the money you're looking for. Or maybe find a shorter tube 6 inch OTA on Astromart. That would give you your added aperture, and portability as well, plus save you a lot of money. They usually can be found at a bargain. Just a thought.

Dunno about the Orion Apex, Dan, but back in 2001 I bought a TV102 to upgrade from the ETX125 I already had. Before selling the ETX I made the mistake of viewing M31 side-by-side with the two scopes. Much more to see in the ETX. Consequently I still own them both.

For lunar, planetary & double stars, what I see in one I'll normally see in the other. TV102 may have a slight edge on double stars. On such DSO's/globular clusters as are suitable for 4" to 5", the ETX rules. Never really minded the narrow FOV either. Did like the ETX's good performance with garden variety plossls and such.

If it came to keeping one, it would probably be the ETX.
But then I'd prefer a good pickup truck over a BMW.
Bob