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Author Topic: Strange resolution numbers at f/2.8 (especially away from the center)  (Read 3310 times)

Offline simont

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This a comment for this page on the website
My previous message was a response to Xzeihoranth, but that's not too apparent from the formatting.

I also have one further question of my own regarding this lens test. I noticed that the measured resolution values at f/2.8 are really low, much lower than at both f/2 and f/4. Could this be a measurement error? If not, what could explain such behaviour and is it common?

Kind regards,

Offline cccx

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Re: Strange resolution numbers at f/2.8 (especially away from the center)
« Reply #1 on: February 19, 2012, 11:08:31 am »
Hi Simont, I agree it is strange, I would also be interested in knowing why this is.

However, it appears to occur on all the camera bodies they tested this lens with.

I was thinking it could be caused by any of the following reasons:

  • -a very 'different' testing methodology by DxO (perhaps taking into account more vertical resolution than any other lens testing site)?
  • -individual lens fault?
  • -lens design
  • -a measurement error by DxO (unlikely if it occurs on all camera bodies they tested)?

Note that the SLRGear test did not show any such behaviour:

The Lenstip review linked to by Xzei showed f2.8 to be one of the highest resolution apertures:

So there are some very different test results for this lens.