[Scythels]

Dear JoJu,

 

I believe you misunderstand what I am trying to say. 

 

 

20-24 MP FF? Come on, you want to bother with minor bread crumbs? Aren't you aiming to higher spheres?

I'm referring to design criteria for many camera lenses.  With camera lenses, it is good practice to design the lens for the sensor it will be mated to.  Obviously this is complicated for ILC lenses, but the 20-24mp FF chip pixel size is fairly typical for camera lens specs. 

 

Here is a 60mm f/1.4 lens design in progress at f/1.4. 

 

http://i.imgur.com/oSMvhFX.png

 

The 30-40lp/mm region is what is "of interest" regarding sharpness for a 20-24mp FF chip.  The dotted line is the diffraction limit.  "Good" lenses are within about 50% of this at decently high spacial frequencies (80 - 120lp/mm is my personal ballpark for f numbers between 1.4 and 4).  Here is the lens again at f/8:

 

http://i.imgur.com/FrkmdqO.png

 

Over most of the sensor, this appears as sharp as is possible. 

 

Here is a very high performance lens working at f/0.9:

 

http://i.imgur.com/URuhQeB.png

 

In case you can't see that this is a real, aberrated lens because of the performance, here is out to 500lp/mm:

 

http://i.imgur.com/sHWPgLV.png

 

This is top-tier performance. 

 

Here instead is something more "common" for "good" lenses:

 

http://i.imgur.com/YPmpwBo.png

 

This piece cost $1500 USD equivalent when it was sold. 

 

So you can see, "general camera lenses" perform rather poorly and there is enormous room to improve.  "Giants" like the 135 aposonnar, or canon 300/2.8L II, or the 400/2.8L II are maybe 60-75% of the way to the performance of that f/2.7 lens I showed. 

 

I am very frank with my opinions.  If this offends you, tough luck =)  I need not be "nice" to any manufacture, I'm not on any of their payrolls and see no reason to treat camera lenses as if they are better than they actually are. 

 

 

As for 35/1.4A vs 35/1.4L - ever cared to take a look at the price tag?

Does it matter?  Obviously in the grand scheme of things it does, but they are not priced in different classes and the extra for the 35L doesn't place it in a class such that it will have tighter tolerances because of the expected customer base (i.e cinema, scientific, or other market with high expectations).  The 35A has twice the variation of the 35L.  If you really want I can dig up the old data and show it to you numerically, but I suspect you have already plugged your ears.

 

 

So, why aren't you quoting Roger properly?

I'm avoiding quoting Roger because there are some things I have been told under NDA and some things I have read on a blog post, the same as you.  It is a defense mechanism to avoid giving out information under NDA.  This is why I also will not disclose the name of the manufacture of the $4500 lens above, or which mfg uses a bookshelf to do QC, and so on. 

 

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bonus factoid: the automotive sector of the photonics industry is currently approximately equal in size to the entire camera industry:

 

http://www.osa-opn.org/home/industry/201...QyjqOHHrL9