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Gary Martin

Gary Martin

Llanelli, Wales

Which is the 2x on the 70-200 f/4L?


One taken with the 400 f/5.6L and I'm not sure it's obvious which is which.


I will read the comments with interest. (Bokeh removed in both as it was a clue)


other sizes: small medium original auto
comment
Gary Martin01-Jul-2005 14:10
I never print out Jim so it not a factor for me. I sent Terry Watson the 100% crops so he might be able to give you his findings.
Jim Thode01-Jul-2005 05:55
Gary,
I was writing my comment and did not see your comment till after I posted my comment.posted. I agree, for web posting at a reduced size, the quality of the lens is much less apparent. However, then viewing at full size or printing larger sized prints the quality of the lens will be more critical. I still would be interested in a 100% crop so we can see the real thing.
Jim
Jim Thode01-Jul-2005 05:45
I say that B is the prime and A is the 200 + 2X based entirely on what saw when you posted the whole group yesterday. The 200 + 2x was smaller then the 400 and Doug also mentioned that the 200 is shy of 200. As far as sharpness goes, it is pointless to compare these reduced images. The quality of this post is poorer then the original (reduced images) that are posted at: http://www.pbase.com/tirc/misc
It would be interesting to see a 100% crop comparing the 400 prime and 200 +2X
Gary Martin01-Jul-2005 05:19
OK the idea wasn't to catch people out, but reading the comments below and on the list, it is clear that no one is SURE which is which!

So in the real life situation, where we tweak contrast, usm etc to improve our pics before uploading, there's not much (if anything) to choose between.

That was the point I was trying to get over.

For the record: A was 2x and B the prime!
Jennifer B. 30-Jun-2005 23:09
I think I am in the minority but I think A is the 70-200+2x and B is the 400. A looks just a little bit sharper. I will be interested in finding out which is which.
Joe Lasker30-Jun-2005 22:20
I'd say A is the prime, though it's harder to tell with how much you've boosted the saturation. Also, you used AF? A seems to be focused on the back wall, and B on the monkey or the bear. The yellow button on the bottom right should be sharper on A, and that's throwing me off. The plane of focus is different in each one, and on the edges where the difference would really show, B is focused closer to the orange bear and the yellow button, the two things I feel I would show the biggest difference.

Or, I could be totally clueless. :)
Digital Rebels30-Jun-2005 22:18
A has better sharpness, greater contrast and cleaner colors so I'll jump on the 'its a prime' bandwagon. However B is a slightly tighter crop and the 70-200 is known for being a bit shy of 200mm at full zoom so that suggests that A is the zoom. If it is, then we need to find a reason for the better saturation on A. A looks a bit darker which might be part of it but that still leaves A as looking sharper. I assume these are both 100% crops (not stated) or the whole concept of a test is worthless.
Doug Smith
Jvan Photography30-Jun-2005 21:33
I think A is the 400mm and B is the 2x on the 70-200 f/4L. A is much sharper, what you would expect from a prime lens. It is a bit more contrasty also something I would expect from the 400mm lens.....hopefully I am correct :-)

Jvan Photography30-Jun-2005 20:52
I think A is the 400mm and B is the 2x on the 70-200 f/4L. A is much sharper, what you would expect from a prime lens. It is a bit more contrasty also something I would expect from the 400mm lens.....hopefully I am correct :-)

Guest 30-Jun-2005 19:44
B is the 400 and A is the 70-200 2x (based on the green of the pants. Do I win a 2x TC .

Jim M
Guest 30-Jun-2005 19:32
My guess is that A is the 400 mm lens and B the 200 mm lens with extender. Image A looks a little more 'pronounced'. ..
chao, Gina