Nikon DX lens on D700

[lsisaxon]

I could loan you one to try, but I am out of town right now. Let's see how this develops...

Just drop me a PM when you're back and we'll see how things go. MTF of the 17-35 doesn't look that promising.

 

[lastboltnut]

Hey Isisaxon, any reason why the old SLR lenses are not good on a FX body? The sensor size is the same as film, so the coverage are suppose to be the same right?

So am I. I thought all my dad's film lenses could be put to great use again with the FX body. Boy was I WRONG! ;p

 

[lsisaxon]

Hey Isisaxon, any reason why the old SLR lenses are not good on a FX body? The sensor size is the same as film, so the coverage are suppose to be the same right?

There are some good ones. But mainly the wideangles are those which suffered because on a digital sensor, there is a piece of AA filter and this required the rays to penetrate perpendicularly to get the best results. That's why the centre is always sharper because the rays are perpendicular. At the corners, depending on the lens, the rays are oblique and this may cause CA and blurness when passing through the AA filter. Also, when the rays strike the sensor element because it's also at an angle, there will be some reduction of light, the severity depending on the angle of incidence. Some sensors already incorporate microlenses to mitigate this.

This was made known to us when Nikon started the DX system. They decided that since there was a need to redesign wideangle lenses, might as well design it for use on a smaller sensor while existing lenses could be still be used in the sweet spot region.

 

[lastboltnut]

Oic, so this is the history. I am really keen to try and take out the AA filter. I have started a thread on this, but seems like no one here has tried it. So with the AA filter off, it will be better. Thanks for the info.

There are some good ones. But mainly the wideangles are those which suffered because on a digital sensor, there is a piece of AA filter and this required the rays to penetrate perpendicularly to get the best results. That's why the centre is always sharper because the rays are perpendicular. At the corners, depending on the lens, the rays are oblique and this may cause CA and blurness when passing through the AA filter. Also, when the rays strike the sensor element because it's also at an angle, there will be some reduction of light, the severity depending on the angle of incidence. Some sensors already incorporate microlenses to mitigate this.

This was made known to us when Nikon started the DX system. They decided that since there was a need to redesign wideangle lenses, might as well design it for use on a smaller sensor while existing lenses could be still be used in the sweet spot region.

 

[lsisaxon]

Oic, so this is the history. I am really keen to try and take out the AA filter. I have started a thread on this, but seems like no one here has tried it. So with the AA filter off, it will be better. Thanks for the info.

What you will get with the AA filter off is aliasing unless the lens resolution is that crappy. But beware also because in the stack is also an IR filter, so there will be some colour shift and the focal plane distance will be lengthened by a little bit because the apparent distance for glass is shorter than air, so there is a chance you might not be able to get infinity focus. Any dust problem will be a speck of clearly defined blob on the image rather than out of focus.

Olympus and Panasonic are using an even smaller sensor, so you can read their philosophy.
http://www.olympus-esystem.com/dea/technology/four-thirds/sensor-size.html

 

[lastboltnut]

Thanks again for the info.

What you will get with the AA filter off is aliasing unless the lens resolution is that crappy. But beware also because in the stack is also an IR filter, so there will be some colour shift and the focal plane distance will be lengthened by a little bit because the apparent distance for glass is shorter than air, so there is a chance you might not be able to get infinity focus. Any dust problem will be a speck of clearly defined blob on the image rather than out of focus.

Olympus and Panasonic are using an even smaller sensor, so you can read their philosophy.
http://www.olympus-esystem.com/dea/technology/four-thirds/sensor-size.html