[opendtv] Mark Schubin on HD lenses

http://www.tvtechnology.com/article/69556

This article focuses on the effects of diffraction, caused by small lens
apertures (high f-stop number), on the maximum possible contrast
achievable. For any given lens resolution spec, small lens apertures
cause diffraction and limit contrast. The greater the lp/mm spec of a
lens is, the more pronounced this diffraction-limited contrast ratio
becomes.

So once again, this points to bigger sensor area being the way to go.
Bigger image area means larger aperture for a given f stop reading,
which results in reduced diffraction of the light. Not to mention,
affordable HD lenses.

Here's a perfect example: the new Canon EOS 5D Mark II. It's a consumer
product, with affordable lens line. Yet, get this, the image area is the
full 24 X 36 mm of 35mm still cameras, and this one offers 22 Mpel
resolution. I think that's a record.

Since most 100 lp/mm lenses are not that good across the entire frame, I
think the 22 mpel sensor is probably about as good as it need to be,
even for really good lenses.

Bert
 
 
----------------------------------------------------------------------
You can UNSUBSCRIBE from the OpenDTV list in two ways:

- Using the UNSUBSCRIBE command in your user configuration settings at 
FreeLists.org 

- By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word 
unsubscribe in the subject line.

Other related posts: