How does STARTRAVEL 600mm f5 compare with Sigma 500mm f4.5? (1 Viewer)

http://www.pulsar-optical.co.uk/prod/telescopes/sky-watcher/short-tuberefractors/startravel-120/az3.html

This cost <$500 while Sigma 500mm f4.5 cost >$3000. This huge telescope is like a 8 feet big guy fighting against a 3 feet dwarf (comparing the size of lens). I really doubt the Sigma lens has better image quality than this cheap telescope (One member has performed an experiment of Sigma 50-500 against scope and found out scope wins). Also, this telescope has direct DSLR connection.

Thus, if it is not for portability issue (when one only uses it in his backyard), why would one not choose this <$500 telescope?

No AF, no aperture, likely metering of the camera will not work ........
And all this has nothing to do with image quality.

ITs comparing apples with oranges. It doesn't make a lot of sense in most aspects.

The comp. of the 50-500 and the digiscoping set-up you mentioned falls into this bracket. Sure if you need magnification nothing beats digiscoping. Digiscoping can produce great images, but it has its limitations.....

baofeng said:

http://www.pulsar-optical.co.uk/prod/telescopes/sky-watcher/short-tuberefractors/startravel-120/az3.html

This cost <$500 while Sigma 500mm f4.5 cost >$3000. This huge telescope is like a 8 feet big guy fighting against a 3 feet dwarf (comparing the size of lens). I really doubt the Sigma lens has better image quality than this cheap telescope (One member has performed an experiment of Sigma 50-500 against scope and found out scope wins). Also, this telescope has direct DSLR connection.

Thus, if it is not for portability issue (when one only uses it in his backyard), why would one not choose this <$500 telescope?

Click to expand...

That is an achromatic telescope with no aperture control and no AF capability. If you ignore the ergonomics for a while, the IQ from that scope is not going to be even close to what you can get from even a reasonably priced lens like the Sigma 150-500 OS.

There are ED or APO scopes with 102-110mm aperture that could provide IQ that are comparable to Sigma 500mm f/4.5 (at least at the center of the frame). These scopes may cost less than half as much as the Sigma 500mm f/4.5 but they would also have no AF support, no aperture control, and they will be heavier and more difficult to use.