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12-05-2012, 10:35 PM   #16
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QuoteOriginally posted by Shanti Quote
would a 200 F2.8 with 2xTC = 400 effective 600mm or a
2x200 = 400, hehe. focal length doesn't change but this would correspond to a 600mm lens on full-frame.

QuoteOriginally posted by Shanti Quote
thanks Adam, is is still available this lens ? and alot of the old ones are WR a bit, at least some OLY were from the good ole days.. The better low light focus of K5II is needed here,so probably I choose that one,as not sure how much better the S will be from what I have seen on the reviews/samples
If you're asking about the K500mm, it was discontinued in the 70's. You can get it second hand for $500-700.


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12-06-2012, 02:08 AM   #17
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I'm enjoying my IIs so far, I'm sure you would too.
12-06-2012, 06:59 AM   #18
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QuoteOriginally posted by Adam Quote
2x200 = 400, hehe. focal length doesn't change but this would correspond to a 600mm lens on full-frame.



If you're asking about the K500mm, it was discontinued in the 70's. You can get it second hand for $500-700.
?? a 2X TC doubles the focal length or did I miss something? question is which combination gives best IQ
12-06-2012, 07:21 AM   #19
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QuoteOriginally posted by Shanti Quote
question is which combination gives best IQ
Any solution using a TC is inevitably going to take a IQ hit.
Depending on the TC, some lens features (eg SDM AF) may also not work.
Approach the TC issue with a lot of careful research.

12-06-2012, 08:48 AM   #20
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QuoteOriginally posted by Shanti Quote
?? a 2X TC doubles the focal length or did I miss something? question is which combination gives best IQ
Adam was saying that a 200mm lens stays a 200mm lens no matter what. Using a TC and/or a crop sensor body you're just taking a smaller part of the field of view. Don't worry, many people say it like this.

Now, on topic, any prime lens with a TC will usually have better image quality than any of the Sigma zooms you mentioned. On the other hand, you should try to keep your maximum aperture under f/5.6 for better AF, light gathering ability and the option to stop down a bit (for sharpness). The only lens that meets these is the 200 2.8 with a 2x converter: 2.8*2=5.6 (here you can do it like this ) which would also be very useful without the TC.
12-06-2012, 09:39 AM   #21
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Using a TC is different than cropping; the lens will be a 200mm, of course, but the lens + TC will be a 400mm.
12-06-2012, 09:20 PM   #22
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QuoteOriginally posted by Giklab Quote
Adam was saying that a 200mm lens stays a 200mm lens no matter what. Using a TC and/or a crop sensor body you're just taking a smaller part of the field of view. Don't worry, many people say it like this.

Now, on topic, any prime lens with a TC will usually have better image quality than any of the Sigma zooms you mentioned. On the other hand, you should try to keep your maximum aperture under f/5.6 for better AF, light gathering ability and the option to stop down a bit (for sharpness). The only lens that meets these is the 200 2.8 with a 2x converter: 2.8*2=5.6 (here you can do it like this ) which would also be very useful without the TC.
Hi Giklab now I have 600mm effective FL with my Oly gear,but lacking resolution & low light capabilities, so I hope the 200 2.8 w/TC will give me the same FOV,with much better IQ.I also think of the 60-250, but w/TC maybe not so good as you say here. As $ is limited I want to make the right choices if possible
12-08-2012, 02:26 AM   #23
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QuoteOriginally posted by Schraubstock Quote
Not sure if I agree, my 60-250 has never let me down as far as image quality is concerned. I have never used the DA*300 so I can't tell but I doubt it is significantly better then what I get from my 60-250. See sample below.
Trust me, a good 300mm prime still is better. But it's great that you're satisfied with the 60-250 - many people really love that lens.

My "curse" is that I own a number of good primes (plus the DA*50-135) in that range, and I've compared many images. It's just not quite as good as the others. I can't decide if I'll like it enough to be worth the trade-off in order to get the convenience of the zoom. I'm afraid it may lack that little extra bit that makes someone really notice a photo, even if they don't know why.

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