28 replies to this topic

[wagg]

hi jeff, yes, i'm very partial to the sw's(being a proud canuck!)having said that, when i first purchased them i'd bought the 7.5mm not the 10. in my 10" f/5 dob it just didn't "look right", so i swapped for the 10mm(and barlow my 14). now that i've purchased a mak, the 127mm from synta i wish maybe i still had it! oh well, another reason for my sweety to roll her eyes when i tell her i "need" to buy a new eyepiece and proceed to delight her with my descriptions of planetary views, fov's etc!
so yeah, i love these 'pieces, especially the 14 and i can't wait for your impressions of the 18mm!
cheers, wagg

[Starman1]

I am in love with the concept of "zoom" eyepieces, but hate the execution thereof. I've owned an Orion, a Vixen, and a Zeiss, and I ended up selling them all. Why?
1) the incredibly narrow field of view at low powers
2) the poorer imaging performance compared to single eyepieces of the same focal length
3) the difficulty of rotating the eypiece to select a new focal length when the eyepiece was very cold (the Vixen was almost unmovable at 0 degrees)
4) None was free of added color at the edge of the field
5) The images were terrible at f/4.5
But, I still found the experience good because:
1) I could dial in the exact best magnification for the object
2) It meant I could change magnifications without changing eyepieces
3) It was a great experience on the Moon!
So, after I read David's review of the Speers-Waler 5-8mm "Zoom",
I said "Hmm! Answers the objections I had with the others (except price, but it's still cheaper than most big Naglers). Maybe....."
So I'm VERY interested in what you all have to say. Refocusing is no big deal. I still think it may be THE Zoom eyepiece.
David, thanks for your comments.
Don

[Tom L]

Don, I believe that both David and Tom stated that the FOV of the SW5-8 was maintained. Tom stated they weren't as sharp and had slight lateral color (Tom T, I'm trying to remember off the top of my head, if I'm wrong let me know) and David did not complain of it. It basically left everything up in the air about the SW5-8 and Jeff took the next step...and I'm close to it myself.

[Craig L]

Don, I believe that both David and Tom stated that the FOV of the SW5-8 was maintained. Tom stated they weren't as sharp and had slight lateral color (Tom T, I'm trying to remember off the top of my head, if I'm wrong let me know) and David did not complain of it. It basically left everything up in the air about the SW5-8 and Jeff took the next step...and I'm close to it myself.

I've posted this before, but briefly, the SW 5-8mm held its own with a Nagler 7mm T6 in terms of subtle detail and faint field stars that were just barely visible when I observed a comet last autumn. I also enjoyed the views of Mars as well. This EP is the best value out there for its focal length(s). It's also not a heavy EP, another bonus.

Cheers,

- Craig