[Brightcolours]

One of interviews with Zeiss said that correcting distortion in post helps to design much smaller lenses.


I think that was one of the main reasons why m3/4 mirrorless lenses in normal and wide range are so much smaller than APS-C mirrorless lenses where only few of them have similar distortion figures

Which interview was that?

 

The main reasons why MFT lenses in normal and wide range as so much smaller:

1. The focal lengths are smaller.
   
2. The flange distance is less than half of what it is for DSLR mounts
   
3. The apertures are so much smaller
   

[Guest]

Which interview was that?
 

Can't google it now it was some years ago

[Guest]

 

1. The flange distance is less than half of what it is for DSLR mounts
   

I'm comparing mirrorless to mirrorless.


Many APS-C pancake lenses have bad distortions as well.

Fuji 18mm, Samsung 16 & 20mm, Sony 20mm.


Fuji 35/2 isn't a pancake but still with a focus on small size and distortions are bad there

 

[Klaus]

The thing is - a barrel distortion of 6+% limits the border resolution to roughly "good to very good". "Excellent" is just not possible when using the corrected image.

[toni-a]

Dunmo how much it's important in the filed since I never used a rectilinear lens with 6% distortion, however I am using 24-105 on film, it has 4% distortions yet, that has never been a problem maybe because I don't do architecture.

I always set distortions correction off, however dunno if 6% is much more than 4% and is really visible in non architecture shots.

In real life with distortion correction off is anything visible ?

Klaus in the review could you post some non corrected shots with alongside the corrected version ?

Believe me guys life is much easier in film world...

[Brightcolours]

I'm comparing mirrorless to mirrorless.


Many APS-C pancake lenses have bad distortions as well.

Fuji 18mm, Samsung 16 & 20mm, Sony 20mm.


Fuji 35/2 isn't a pancake but still with a focus on small size and distortions are bad there

 

What does pancake have to do with anything, though? Many pancake lenses do not have bad barrel distortion. The many Pentax DSLR pancakes, the Canon 24mm f2.8 and 40mm f2.8 DSLR pancakes, the mirrorless Canon 22mm f2 pancake to name a few.

 

Lenses from the past which are small have no very bad distortions either. It is just that now some lens designers and brands take liberty with distortion in the lens design because they can hide it with correction in JPEG conversion.

 

My very small Canon EF 35mm f2 does not have excessive distortion either.

[eggybread]

6.15% distortions at 12mm ...

thats for the old Pana 12-60mm f3.5-5.6 though right, not the new f2.8-4 ?

[Guest]

Aren't the borders more important at the wide end than the long end ? If so why do they design the lenses to have maximum distortion at the wide end. Is this a property of the angle or could they flip things and make the wide angle more linear and the long end more pincushion ?

 

The thing is - a barrel distortion of 6+% limits the border resolution to roughly "good to very good". "Excellent" is just not possible when using the corrected image.

I believe it is the current results from testing of this lens ...

 

thats for the old Pana 12-60mm f3.5-5.6 though right, not the new f2.8-4 ?

[Klaus]

Yes, the figure was about the new one.

[Brightcolours]

Aren't the borders more important at the wide end than the long end ? If so why do they design the lenses to have maximum distortion at the wide end. Is this a property of the angle or could they flip things and make the wide angle more linear and the long end more pincushion ?

 


I believe it is the current results from testing of this lens ...

 

thats for the old Pana 12-60mm f3.5-5.6 though right, not the new f2.8-4 ?

Uncorrected lenses are called "fisheye". The only uncorrected lenses you see nowadays that do not correct for fisheye distortion are very wide angle lenses, because those are for maximum effect (and of course maximum FOV).

An uncorrected lens never shows things as "pin cushion", that is an effect of over correction.

If you undercorrect at a wide angle, it shows up stronger than in longer focal lengths.