bought my self new Bintel 2" Quartz dielectric Diagonal
Is there any diference between WO and bintel in performance wise
The both Quartz dielectric Diagonal with 99% reflectivity but WO cost twice as much as Bintel
Hi Alex, I would not know how good the Bintel diagonal is , but I have the WO one and its very , very good , Lovely fit and finish and it just dissapares when using it .
Brian.
I have had quite a bit of experience with quite a few different diagonals. The first point I would mention is to make sure you have the right type suited to your particular scope in terms of whether it is a prism or mirror. Remember - Takahashi largely make prism diagonals for a reason so it isnt a simple matter of mirror is always better.
With this initial caveat mentioned in my own experience there isn't much optical difference in any of the low to medium level (i.e. price) diagonals. The differences only really become manifest when you start spending the big bucks for an absolute top end diagonal. In terms of reflection and flattness etc I haven't really be able to discern anything between a quartz GSO or quartz WO etc. The fit and finish with carbon fibre side plates and swan logos are certainly nicer on the WO products over the GSO. However, as far as doing the actual optical job I wouldn't lose any sleep over either a GSO/Bintel or WO/Orion as one being better than the other.
If you want piece of mind in thinking you are buying the best and getting everything/every photon you can from your diagonal then buy a top end diagonal as it will prove to be a life long investment.
Finally, with the top end diagonals the differences IMHO really only boils down to two factors - 1) fit, finish and construction 2) Quality control. With the former you can expect a solid one piece housing construction with perfectly blackened edges everywhere and no rough edges or cheapy compression rings etc. On the latter point you can have more confidence that if "your" diagonal was, by some rare remote chance, actually subjected to any of the high powered optical tests of reflectivity and flattness it would indeed meet the advertised/represented specifications of the manufacturer.
One difference between the diagonals is clear aperture, which is only important if you're using eyepieces with field stops greater than 42mm. The GSO/Bintel has about 46mm clearance while the WO has 40mm; the WO would noticably vignette a 41mm Panoptic (field stop 46mm) for example.
I've used both and have to agree with Tony and Dan.
In practice (vignetting aside) there is no discernable optical difference - indeed the mirrors may well come from the same factory in Taiwan.
The WO certainly has better finish, but I like the Bintel for its low weight.
Hi Alex, In my opinion, if you have two identical telescopes side by side in the middle of a paddock in a dark sky, one scope with a WO diagonal and one with a BinTel diagonal, optically 99% of people couldn't/wouldn't be able to tell the difference (apart from said vignetting). And I think that goes for most comparisons of cheap vs. top-end optical accessories (perhaps primary mirrors aside).
Hi Alex, I would not know how good the Bintel diagonal is , but I have the WO one and its very , very 
good , Lovely fit and finish and it just dissapares when using it .
