Any updates on this thread?
Comparisons between SDLv3, SDLv2 and HDFT...
- for sharpness/resolution
- contrast and colour tones
- brightness
- FOV
- eye relief
- ease of use with glasses
Got an MM3 ED50 with HDFT zoom. Thinking about an upgrade on the eyepiece?
Nick
I recently purchased a MM4 60 GA ED/45 Travelscope + HDF T 15-45x Eyepiece. I bought it to give me a smaller and lighter alternative to my old Pentax PF-65 (plus Vixen 8-24mm eyepiece). I was expecting the Opticron to not be as good as my Pentax (even though 15 years old), but just lighter and smaller, so I decided to get the less expensive HDT eyepiece.
Well, it turned out that I like the Opticron a lot better than my Pentax, so I was kind of wishing I'd gotten the SDLv3 eyepiece instead (since the Opticron was going to be my main scope now).
Well, I can resist anything but temptation, so I bought a used SDLv3 (for $250 in perfect condition). So I now have both. Since I wear glasses, eye-relief is critical to me. One of the small complaints I had about the HDF eyepiece was that the ER at minimum zoom was actually too much, causing black-out problems. Then, when I zoomed in, it fairly quickly lowered the ER so that it was then somewhat less than I wanted (only somewhat, but noticable).
I had looked at the specs and the HDR is shown as having an ER of 22mm-17mm. This seemed to match what I was seeing with the scope. I know from experience that 18mm is the sweet spot for ER for me, and that 20 is a little too much.
The SDLv3 ER is shown as 20mm-18mm. So, hey, that seemed better and the reason I splurged and bought it. I can say having used it that it does seem better in just the way I wanted. I DO have some black-out problems at minimum zoom, but not as bad, and when I zoom in, the ER lowers some and is just about perfect for me, remaining so for the rest of the zoom.
As far as sharpness, brightness, and field-of-view, it is hard for me to say because I only have the one scope body (so it's hard to compare), and there's nothing that smacks you in the face as being different in these areas between the 2 eyepieces. I guess the SDLv3 seems somewhat wider but it's not significant, IMHO. They are both very nice.
One other thing - the HDF has the oddest twist eyecup design - turning it clockwise makes it go UP (huh?). The SDLv3 works the way every other twist eyecup I have ever used - clockwise goes DOWN, counter-clockwise goes up (ya think?!?). Another nice thing about the SDLv3 eyecup is that pushing down on it will not make it go down; you have to slightly lift up on it and then turn it clockwise to make it go down (you have to get used to this). This prevents you from collapsing it in use (although I use it fully down already).
So I can see why there are varying reports about whether the SDLv3 is worth the extra cost. If you wear glasses, I think it is. Otherwise, I think the HDF is about as good. Even with the ER being important to me, I don't think I would have spent the money for a new SDLv3, which is over $400 nowadays in USA (although it would have been cheaper had I bought it when I bought the body, so that would have been the way to go, in hind-sight). I got lucky finding it used and I think still worth doing.
Hope this helps.
