10-07-2010, 12:37 AM
[quote name='Brightcolours' timestamp='1286386779' post='3538']
Enjoyable again, as always. Thanks for the effort!
[/quote]
Glad you liked it Brightcolours. Thanks for the feedback...
[quote name='Brightcolours' timestamp='1286386779' post='3538']
A few remarks though:
* I think it would be a bit more informative to test both at f1.4, to see actual differences in same circumstances.
[/quote]
I gave this a lot of thought before doing the f/1.2 vs. f/1.4 comparison. When I'm comparing sensors, I always opt to resize the one with more MPs down to the size of the smaller one (e.g. similar to DXOMark's "print" SNR) because if someone's considering say a 12MP sensor, they're happy to live with a 12MP image. By resizing the larger (>12MP) one down to the same size, resolution requirements are still met but you can also reduce the noise that troubles sensors with more pixels (per unit area).
In the case of the 85L's image quality, there's nothing really it lacks against the 85G when it's wide open at f/1.2. It's even a bit sharper in the center if you look close enough. The two lenses do have slight differences (at max aperture) but these will most definitely not show up when doing anything other than a scientific shot. In other words, there really is nothing to gain by shooting the 85L @ 1.4 because the f/1.2 effect (DOF, speed) is a lot more prominent in the final shot than any IQ differences. Plus it also means more work for me <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='
' />
[quote name='Brightcolours' timestamp='1286386779' post='3538']
* Your bokeh tests are not the best for showing how a lens performs... A test with a more busy background will be more conclusive about the quality of bokeh to expect in normal usage.
The lenstip samples and subject matter hint at a much more "busy" bokeh rendering from the new Nikon compared to the Canon.
[/quote]
Yes, it would have been interesting to have chosen a scene with an even busier background for the whole frame bokeh test but what I have is still a fairly busy background (although completely blurred) and you can still see how the lenses compare against each other. The focusing distance for that shot was a bit over 1m, which is around the distance you'd be with a 85mm for a head and shoulders portrait. I did mention in that particular test's description that the 85L's bokeh seems a bit smoother and it seems to coincide with what you came across on that site.
Bokeh does change depending on the focusing distance, being in front or behind the focus and where it is on the frame. It's quite difficult to accurately test for all these combinations + the different types of bokeh subject combinations (point lights, low/high contrast, high/low frequency lines, etc.). That's about 144 test combinations right there <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='' />
[quote name='Brightcolours' timestamp='1286386779' post='3538']
It has been a while seeing a holden commodore <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/wink.gif' class='bbc_emoticon' alt='' />.
[/quote]
lol... it's an old one too
Thanks again for the comments.
GTW
Enjoyable again, as always. Thanks for the effort!
[/quote]
Glad you liked it Brightcolours. Thanks for the feedback...
[quote name='Brightcolours' timestamp='1286386779' post='3538']
A few remarks though:
* I think it would be a bit more informative to test both at f1.4, to see actual differences in same circumstances.
[/quote]
I gave this a lot of thought before doing the f/1.2 vs. f/1.4 comparison. When I'm comparing sensors, I always opt to resize the one with more MPs down to the size of the smaller one (e.g. similar to DXOMark's "print" SNR) because if someone's considering say a 12MP sensor, they're happy to live with a 12MP image. By resizing the larger (>12MP) one down to the same size, resolution requirements are still met but you can also reduce the noise that troubles sensors with more pixels (per unit area).
In the case of the 85L's image quality, there's nothing really it lacks against the 85G when it's wide open at f/1.2. It's even a bit sharper in the center if you look close enough. The two lenses do have slight differences (at max aperture) but these will most definitely not show up when doing anything other than a scientific shot. In other words, there really is nothing to gain by shooting the 85L @ 1.4 because the f/1.2 effect (DOF, speed) is a lot more prominent in the final shot than any IQ differences. Plus it also means more work for me <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='
' />[quote name='Brightcolours' timestamp='1286386779' post='3538']
* Your bokeh tests are not the best for showing how a lens performs... A test with a more busy background will be more conclusive about the quality of bokeh to expect in normal usage.
The lenstip samples and subject matter hint at a much more "busy" bokeh rendering from the new Nikon compared to the Canon.
[/quote]
Yes, it would have been interesting to have chosen a scene with an even busier background for the whole frame bokeh test but what I have is still a fairly busy background (although completely blurred) and you can still see how the lenses compare against each other. The focusing distance for that shot was a bit over 1m, which is around the distance you'd be with a 85mm for a head and shoulders portrait. I did mention in that particular test's description that the 85L's bokeh seems a bit smoother and it seems to coincide with what you came across on that site.
Bokeh does change depending on the focusing distance, being in front or behind the focus and where it is on the frame. It's quite difficult to accurately test for all these combinations + the different types of bokeh subject combinations (point lights, low/high contrast, high/low frequency lines, etc.). That's about 144 test combinations right there <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='
' />[quote name='Brightcolours' timestamp='1286386779' post='3538']
It has been a while seeing a holden commodore <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/wink.gif' class='bbc_emoticon' alt='
' />.[/quote]
lol... it's an old one too
Thanks again for the comments.
GTW