300/5.6 CAT
I picked up a Spiratone 300/5.6 mirror lens on eekBay for $5.50. I'd never seen one and this one was sold as parts, couldn't resist. All it needed was a good cleaning. Major PITA on a CAT, I discovered. :-( Actually even clean it's still a terrible lens, but BOY oh BOY is it fun! Tiny, and really LONG on the D. Anybody know if any one makes a good 300/5.6 CAT? Don
Re: 300/5.6 CAT
Hi Don, as I understand it, due to the optical arrangement proper alignment of a catadioptric or pure mirror lens is very sensitive to error. As the optical path is folded upon itself so much, a slight aligning error gets magnified several times. That surely doesn't help in building a good cat lens. And it might have been also misaligned from factory or previous owner. AFAIK I have read good things about the Tamron SP 350/5.6 catadioptric, but I never tried it myself. Good light! fra
Re: 300/5.6 CAT
I've seen a few new 300mm cats, they might be better, but I doubt it. Hey for $5.50 you shouldn't complain, they sell for a $300-$400 new. Don Sanderson wrote: I picked up a Spiratone 300/5.6 mirror lens on eekBay for $5.50. I'd never seen one and this one was sold as parts, couldn't resist. All it needed was a good cleaning. Major PITA on a CAT, I discovered. :-( Actually even clean it's still a terrible lens, but BOY oh BOY is it fun! Tiny, and really LONG on the D. Anybody know if any one makes a good 300/5.6 CAT? Don -- I can understand why mankind hasn't given up war. During a war you get to drive tanks through the sides of buildings and shoot foreigners - two things that are usually frowned on during peacetime. --P.J. O'Rourke
Re: 300/5.6 CAT
Tamron makes a pretty good 350/5.6 that's only about 3 inches long. Warren
Re: 300/5.6 CAT
Anybody know if any one makes a good 300/5.6 CAT? How about a Pentax 300/5.6 ? http://www.cetussoft.com/pentax/mirrors/30056.jpg Or, a Pentax 500/8 ? http://www.cetussoft.com/pentax/mirrors/5008.jpg heh-heh Fred
Re: 300/5.6 CAT
AFAIK I have read good things about the Tamron SP 350/5.6 catadioptric, but I never tried it myself. I wouldn't be surprised. I think that the Tamron SP 500/8 is the best 500 Cat I've ever used (and the only 500 cat I still have). My three favorite cats are the VS1 450/4.5 Aspheric Cat, the Tamron SP 500/8 cat, and the VS1 600/8 Solid Cat. Fred
Re: 300/5.6 CAT
F I wouldn't be surprised. I think that the Tamron SP 500/8 is the F best 500 Cat I've ever used (and the only 500 cat I still have). F My three favorite cats are the VS1 450/4.5 Aspheric Cat, the Tamron F SP 500/8 cat, and the VS1 600/8 Solid Cat. In an old test I might still have hidden somewhere in the dark corridors of my harddrive, very highly were praised the catadioptric lenses from telescope manufacturers. They were the best tested. Although I don't think lens tests give much about the lens, it is still for some consideration. After all, a telescope maker should know how to make good optics and how to grind mirrors to 1/3 wavelength precision ;-) Good light! fra
Re: 300/5.6 CAT
Anybody know if any one makes a good 300/5.6 CAT? How about a Pentax 300/5.6 ? http://www.cetussoft.com/pentax/mirrors/30056.jpg Or, a Pentax 500/8 ? http://www.cetussoft.com/pentax/mirrors/5008.jpg heh-heh Fred The Pentax 300/5.6 is a disaster. It was meant to be used as an angled spotting scope but came with a T-mount adapter to permit its use on a camera. Low saturation, very hot spot, etc. I sold mine as soon as I got my first results. I'm not sure it was made by Pentax. Pentax was not engraved in any metal part if I remember well. The Pentax name is on a sticker. Andre
