Just bought a 15mm BST Starguider EP. I already have a 12mm which is excellent, but not so good at the edge. The 15mm is much sharper than the 12mm at the edge. Is this normal with this lens or have I got a duffer?
Also you can unscrew the bottom element and swap them over, when you do this the 15mm loses it's edge sharpness and the 12mm is sharp. So it must be the bottom lens where the problem is.
The 15mm is superb, not the widest FoV, but really sharp. Excellent value for money. Highly recommended.
Sorted. my fault. when I got the 12mm BST there was a slight rattle, this was in the lens that wasn't quite tight enough inside the lower body. Like you do I took it out to see how it fits, put it back and tightened it up. However when I took a closer look at the lens and compared it to the new 15mm, it became obvious that I had screwed the lens in the wrong way. It's now back in the correct way and it is also a superb EP. Anyone with a spotting scope that takes these should give then try. They really are excellent. and only £49.
Also you can unscrew the bottom element and swap them over, when you do this the 15mm loses it's edge sharpness and the 12mm is sharp. So it must be the bottom lens where the problem is.
The 15mm is superb, not the widest FoV, but really sharp. Excellent value for money. Highly recommended.
Sorted. my fault. when I got the 12mm BST there was a slight rattle, this was in the lens that wasn't quite tight enough inside the lower body. Like you do I took it out to see how it fits, put it back and tightened it up. However when I took a closer look at the lens and compared it to the new 15mm, it became obvious that I had screwed the lens in the wrong way. It's now back in the correct way and it is also a superb EP. Anyone with a spotting scope that takes these should give then try. They really are excellent. and only £49.
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