erick
30-04-2007, 11:04 PM
Many thanks to Steve (Janoskiss) who very kindly lent me two eyepieces for my recent week away, after I had posted seeking comments on a better 9mm eyepiece. I had figured that a shorter focal length eyepiece should be my first eyepiece upgrade (when I could afford it).
Steve lent me an 8.5mm Pentax XF and a 13mm Orion Stratus.
I read what all you experts say and am embarrassed to try and say anything from my position of very little knowledge and experience, but I can only tell you what I can.
All I have to compare with are the Bintel 9mm and 15mm Plossls ($39 retail each) that come "packaged" with the telescope (8" 1200mm focal length reflector). (see attached photos - excuse the rubber o-ring plus "yellow tac" on the 9mm - that gets it close to parfocal with the 15mm :P)
Not surprisingly, I much preferred using the Pentax and the Orion to these Plossls. It was a delightful surprise the first time I looked into a wide field of view, compared to that of the Plossls. I felt so much less constrained and could easily find the right place for my eye in both eyepieces to enjoy a clean and bright view of the whole field. Given they retail for at least 5 times as much, I would have been disappointed if I hadn't said "Wow!", which I did!
There were a few times the seeing was good enough that I was able to get to a 2x Barlowed (using Bintel's 2" ED Barlow) 8.5mm lens which had the magnification up over 280x. At that point, my inexperienced eye/brain was working hard to pull enough photons out of the eyepiece, but I know I did spend a while studying and enjoying the images I was seeing - I didn't give up early - so I must have found it satisfactory. I didn't get onto the planets (or I think seeing was very poor when I tried Saturn) but I recall looking deeply into 47Tuc and enjoying the detail.
I did notice, however, that I only used the Orion on one night. The second night I took it out, it sat mostly unused and the last night it didn't even come out. It was the bulk and weight of the eyepiece, not the quality of view or eye relief. Though I wasn't comparing the same focal lengths, I could not see why I would select the bulk and weight of the Orion over the slender elegance of the Pentax. Yes, I know it is a good bit bigger and heavier than the Plossls, but it never really felt that way as I handled the eyepieces in the dark - nothing like the Orion.
I suspect I'll be in the market for one of these 8.5mm Pentax XFs when I have the funds available.
I warned you - I didn't know much! But there it is. :)
Steve lent me an 8.5mm Pentax XF and a 13mm Orion Stratus.
I read what all you experts say and am embarrassed to try and say anything from my position of very little knowledge and experience, but I can only tell you what I can.
All I have to compare with are the Bintel 9mm and 15mm Plossls ($39 retail each) that come "packaged" with the telescope (8" 1200mm focal length reflector). (see attached photos - excuse the rubber o-ring plus "yellow tac" on the 9mm - that gets it close to parfocal with the 15mm :P)
Not surprisingly, I much preferred using the Pentax and the Orion to these Plossls. It was a delightful surprise the first time I looked into a wide field of view, compared to that of the Plossls. I felt so much less constrained and could easily find the right place for my eye in both eyepieces to enjoy a clean and bright view of the whole field. Given they retail for at least 5 times as much, I would have been disappointed if I hadn't said "Wow!", which I did!
There were a few times the seeing was good enough that I was able to get to a 2x Barlowed (using Bintel's 2" ED Barlow) 8.5mm lens which had the magnification up over 280x. At that point, my inexperienced eye/brain was working hard to pull enough photons out of the eyepiece, but I know I did spend a while studying and enjoying the images I was seeing - I didn't give up early - so I must have found it satisfactory. I didn't get onto the planets (or I think seeing was very poor when I tried Saturn) but I recall looking deeply into 47Tuc and enjoying the detail.
I did notice, however, that I only used the Orion on one night. The second night I took it out, it sat mostly unused and the last night it didn't even come out. It was the bulk and weight of the eyepiece, not the quality of view or eye relief. Though I wasn't comparing the same focal lengths, I could not see why I would select the bulk and weight of the Orion over the slender elegance of the Pentax. Yes, I know it is a good bit bigger and heavier than the Plossls, but it never really felt that way as I handled the eyepieces in the dark - nothing like the Orion.
I suspect I'll be in the market for one of these 8.5mm Pentax XFs when I have the funds available.
I warned you - I didn't know much! But there it is. :)