Matching Barlows

[Adrian]

Orion Shorty-Plus 2x barlow (same as Celestron Ultima) and Revelation (GSO) 2.5x barlow. Both of these are 3 element type so should give less CA than ordinary 2 element types. They are also shorty style so fit in my diagonal for visual.

I've mainly used the Orion for webcam planetary work and have just received the revelation to get a slightly larger scale image when conditions allow.

In my scope these give f20 & f25 (or in a 2" diagonal or a 100mm (ish) extension tube would give around f24 & f30)

But which is which?

The Orion costs £80 plus (I got mine second hand for £25 as the vendor had it as a Shorty, not a shorty-plus )

The Revelation costs £31 from Harrison Telescopes and has a safety undercut and compression ring (the Orion has neither).

If the view through the Revelation is as good as the Orion then I think it is a bargain .

[John]

I'll be very interested in how you find these compare. I've owned a Shorty Plus and the Celestron Ultima (which is exactly the same as the Shorty plus) and found them very good barlows. I was interested in the 2.5x Revelation for a while but read some adverse comments on it's performance so didn't bother with it in the end.