[Guest]

I notice I end up never finding reviews of newer third party lenses on the Nikon side. I end up turning to the canon section and reading those reviews, and assuming (probably incorrectly) that they'll fare the same on a Nikon camera.



Just curious, why is it easier for the reviewers to do canon reviews? Do you guys just happen to have more access to these lenses?



I'm not complaining because I know you guys do this stuff in your spare time (and I certainly appreciate your opinions) - but I'd just like to understand the inequality. Would it make it easier if more Nikon shooters donated lenses to you for testing?



-Curriguy

[Guest]

[quote name='curriguy' timestamp='1289902020' post='4196']

I notice I end up never finding reviews of newer third party lenses on the Nikon side. I end up turning to the canon section and reading those reviews, and assuming (probably incorrectly) that they'll fare the same on a Nikon camera.



Just curious, why is it easier for the reviewers to do canon reviews? Do you guys just happen to have more access to these lenses?



I'm not complaining because I know you guys do this stuff in your spare time (and I certainly appreciate your opinions) - but I'd just like to understand the inequality. Would it make it easier if more Nikon shooters donated lenses to you for testing?



-Curriguy

[/quote]

Well lenses will not fare the same but compartivly.

Sharpness: The general charcteristic will be the same regardless of whether a lens is used on a Nikon or Canon camera.Eg the differnce between center and border performance will be comaparable. Of course absolute resoulution numers are not the same since differnt sensor produce different absolute mtf curves. However if the resolution of lens A is better than that of lens B on Canon you will know that lens A is also better than lens B on Nikon.



Vignetting. Nikon's APS-C sensor is slightly larger than Canon's, so vignetting is a bit more pronounced in the corners of Nikon Cameras. If you shoot jpg, overal vignetting appears to be stronger with canon,however as canon aplies a steeper tone curve to the image.



CA

is different, because photozone measures it in pixel width. Thus with a more pixel dense sensor, Ca will be larger, the more pixels a sensor has.



Distortion

Should be almost the same. But again, because of the slightly larger dimensions of the Nikon sensor, a lens can distort slightly more on Nikon than on Canon.



Overal, Id say the canon tests provide a very good and reliable guideline to guess a lenses perfomance on a Nikon camera. Just dont start comparing absolute numbers across systems. This is bound to fail and not necessry anyway.

[Klaus]

[quote name='curriguy' timestamp='1289902020' post='4196']

I notice I end up never finding reviews of newer third party lenses on the Nikon side. I end up turning to the canon section and reading those reviews, and assuming (probably incorrectly) that they'll fare the same on a Nikon camera.



Just curious, why is it easier for the reviewers to do canon reviews? Do you guys just happen to have more access to these lenses?



I'm not complaining because I know you guys do this stuff in your spare time (and I certainly appreciate your opinions) - but I'd just like to understand the inequality. Would it make it easier if more Nikon shooters donated lenses to you for testing?



-Curriguy

[/quote]



Well, we've just tested 3 Nikon lenses. :-)



But seriously - the Canon and Nikon tests are performed by different editors (at different locations).

Being the site owner I'm more into this, of course, and I'm currently performing the Canon tests.



That said - the Nikon APS-C tests were based on the D200 and during the last half year or so we simply faded this out for obvious reasons.

Markus just got the D7000 so this section will be refreshed again. If the progress turns out to be too slow I will do some Nikon testing as well.

[Tiz]

Wouldn't it be interesting and somewhat innovative to test a view good lenses (e.g. highy quality standard zooms from Canon, Nikon, Olympus, Sigma, Tamron (old 17-50)) with the same body (e.g., Olympus EPL-1 or Sony NEX (although this would exclude FT lenses))?



Obviously, this would not tell us a lot about corner performance on the designated bodies. But the sharpness results would be interesting.

[Klaus]

[quote name='Tiz' timestamp='1290011521' post='4213']

Wouldn't it be interesting and somewhat innovative to test a view good lenses (e.g. highy quality standard zooms from Canon, Nikon, Olympus, Sigma, Tamron (old 17-50)) with the same body (e.g., Olympus EPL-1 or Sony NEX (although this would exclude FT lenses))?



Obviously, this would not tell us a lot about corner performance on the designated bodies. But the sharpness results would be interesting.

[/quote]



Sounds academic to me. You tend to have a Nikon or Canon body but not both.

Besides it's technically not possible - you cannot stop down Canon EF lenses on non EOS bodies.

[Tiz]

[quote name='Klaus' timestamp='1290014247' post='4218']

Sounds academic to me. You tend to have a Nikon or Canon body but not both.

Besides it's technically not possible - you cannot stop down Canon EF lenses on non EOS bodies.

[/quote]



Agreed. It would be somewhat academic because it would only answer the question whether there are significant differences between Canon, Nikon etc. glass. In other words, the test might merely help to decide for or against a specific lens mount. That's why I suggested to test only a few good lenses.



Stopping down the EF lenses for the test would not be an issue. I am sure you have an old EOS body. You can stop down the lens and thereafter put it on the EVIL test body.

[dave9t5]

[quote name='Tiz' timestamp='1290014913' post='4219']

Agreed. It would be somewhat academic because it would only answer the question whether there are significant differences between Canon, Nikon etc. glass. In other words, the test might merely help to decide for or against a specific lens mount. That's why I suggested to test only a few good lenses.



Stopping down the EF lenses for the test would not be an issue. I am sure you have an old EOS body. You can stop down the lens and thereafter put it on the EVIL test body.

[/quote]



Testing a bunch of "highy quality standard zooms from Canon, Nikon, Olympus, Sigma, Tamron" would not tell anything about the "differences between Canon, Nikon etc. glass" because you can't generalize from the performance of a bunch of middling zooms (even high-quality ones are forced to make specific compromises depending on the how the designer weights the importance of the many variables (center, edge, sharpness, CA, vignetting, distortion, size, weight, range, etc)).



Conversely, if you narrow your test to comparing say 50/1.4 primes, which might be considered the 'entrance-exam', it still won't tell you which manufacturer makes a good zoom/tele/WA/etc.



Finally, unless you are planning to either develop your own back based around a certain lens-mount or are stuck on film, comparing lens mounts is useless because you need something on both sides of the lens mount, not just glass on one side.

[Tiz]

Not sure whether this is correct.



Example: if I know that the Canon 17-55 IS is 50% less sharp than the famous Zuiko 14-54, I can also conclude that the Canon 70-300 IS is less sharp than the Zuiko 50-200 zoom. This is because the test figures for each lens mount system are already available and comparable.

[popo]

[quote name='Klaus' timestamp='1290014247' post='4218']

Sounds academic to me. You tend to have a Nikon or Canon body but not both.

Besides it's technically not possible - you cannot stop down Canon EF lenses on non EOS bodies.

[/quote]

I heard of a trick, but never tried it myself until now and it works at least on the 50mm f/1.8 II. It is to set the desired aperture on a body as normal and activate it with DoF preview. Keeping it down, disconnect the lens. Sure enough, the aperture remains set in place.

[mst]

[quote name='Tiz' timestamp='1290024748' post='4221']

Example: if I know that the Canon 17-55 IS is 50% less sharp than the famous Zuiko 14-54, I can also conclude that the Canon 70-300 IS is less sharp than the Zuiko 50-200 zoom. This is because the test figures for each lens mount system are already available and comparable.

[/quote]



No. You can not conclude, and they are not comparable.



Apart from that: even if they were, what practical conclusion do you think you could draw from that?



-- Markus