Originally posted by jocelys1 I had a bad experience with 1.7x and sold it. On the A*300, while I will get the reach, the 1.7x converter will not help with the resolution at the distance, which is why I thought the 150-450 might do a better job. Does that make any sense ?
If that's what happened, then it doesn't matter if it makes any sense, it just is what it it. My two DA* lenses works well with the 1.7, as do my Tamorn 90, Sigma 70, etc. Every high quality lens I've tried it with. So it's kind of surprising id didn't work with the A*300. But I don't know the lens,
Understanding folks saying a TC doesn't ad more detail. - PentaxForums.com
The biggest problem I've had getting detail with the Tamron 300 2.8 is lens movement. It's rare you have a chance to completely lock your tripod, and use the two second timer. The 1.7 exaggerates lens movement, 1.7x as well as increasing image size.
As to whether or not the 150-450 will do better, that would require some testing by someone who has both to work out what the parameters around that would be.
I guess the things buyer, you know the A*300 and 1,7 won't do what you want, the only question is will the 150-450? You should rent one. Or if your serious, find a company to buy from who will let you return it if it doesn't do what you want.
I'm not sure I've ever seen an image taken with this lens, so I don't even have a post to point you to. On the forum the A*300 is rated a 10, but we have no idea what that means except everyone who owned it thought it was an exceptional lens (all three of them) . Would they think that if they owned a 150-450? Who knows?
One did post images that are no longer available taken with the 1.7, so how bad could it have been?
I recently did som time with the A-400 and the 1.7. it would be hard to comprehend how the A*300 would be worse.
https://www.pentaxforums.com/forums/122-lens-clubs/55946-300mm-plus-lens-clu...ml#post3962692
Looking at these reviews from 2007 and 2008, I wish they could be redone by folks who have used more modern lenses. we know they were good 10 years ago, but over the last 10 years, the whole heavily corrected edge to edge sharp craze has really taken hold.