Nikon D800E with 14-24

Started Jul 16, 2012 | Discussions thread
Marianne Oelund Veteran Member • Posts: 7,240
A few distorted concepts

PatFahey wrote:

Well... yes and no. I don't want to keep beating this dead horse,

I never would have guessed.

but many times changing a single parameter alone might not be identifiable.

It would be pointless. They do not need to change anything; it's easy enough to write a true lossless algorithm.

Nikon's algorithm may be truly lossless. My point is that we have no way of knowing. And if you are not short of storage space, or time, why risk it?

Oh yes, we have a way of knowing. The C source code for the decompression algorithm is publicly available.

I suspect that the OP's problem is more tied to the angle that the light is hitting the sensor. A lens as short as a 14mm -- even with a retro-focus design -- is going to create a pretty steep angle at the corners of the sensor.

Ray angles at the sensor are strictly a function of the lens aperture (possibly ameliorated slightly by telecentric design), not the lens focal length.

So diffraction that might not be noticeable at F8 on a 24mm lens, appears a lot worse at f8 at 14mm. Think of shining a flashlight at a wall at a 90deg angle. Now swing that flashlight to 45 degrees. See how much bigger the "error" becomes?

You're confusing object space with image space. Diffraction softening, like the ray angle at the sensor, is strictly a function of the lens aperture. It is not a function of the ray angle w.r.t. the optical axis, where the ray enters the lens.

Correcting (or managing) that is something that Leica has done fairly well on the M cameras with directed micro lenses.

Directed microlenses address peripheral vignetting, not lens aberrations, and not diffraction softening. Are you not aware that Nikon also use directed microlenses?

What is it they say, any angle over 15deg is generally unacceptable? The 14-24 at 14 could be approaching (or passing) that mark.

The 14-24 is an f/2.8 lens. The image-plane ray angles are much more modest, than for an f/1.4 lens.

Post (hide subjects) Posted by
(unknown member)
MOD TOF guy
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow