Unnatural geometry of "field-flattened" binoculars? (1 Viewer)

Henry:

I recall a photo you posted some years ago, about the edge distortion or lack of with the Swarovision.

That would be good to post again. There are advantages to the flat field optics. There are differences,
Nikon started it with the SE series, then the LX, HG, and the EDG. These are very pleasing to most users.

Allbinos is a good source for their observations of the many kinds of distortion, in their reviews.

Jerry

Zeiss has done well in my experience with the SF.

Hi Jerry,

Here are some threads with photos of distortion in Swarovisions and others, including a Nikon SE and EDG.

http://www.birdforum.net/showthread.php?t=161309

http://www.birdforum.net/showthread.php?t=175077

http://www.birdforum.net/showthread.php?t=237219

http://www.birdforum.net/showthread.php?t=308250

http://www.birdforum.net/showthread.php?t=313034

No photos in the last one, just my description of the distortion I saw in a Zeiss 8x42 SF.

IMO Albinos is one of the worst sources for information on distortion. They seem to be aware of the existence of only one type, pincushion. They treat it as a defect rather than a design choice and they use a subjective and unreliable method to "measure" it.

Henry

henry link said:

IMO Albinos is one of the worst sources for information on distortion. They seem to be aware of the existence of only one type, pincushion. They treat it as a defect rather than a design choice and they use a subjective and unreliable method to "measure" it.

Henry

Click to expand...

Indeed, and it can affect a binoculars final rankings.

If they were ever to test the Canon 10x42L you would have the binocular scoring a 9 or 10/10 in the category 'Blurring at the edge of the FOV' because it's a flat field design and perhaps 3/10 in 'Distortion the distance of the first curved line from the field centre'. The reality is Canon optical designers know exactly what they are doing dialling in pincushion.

These WWII German rangefinders would be interesting to look through. Coastal battery and AA 1943

henry link said:

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IMO Albinos is one of the worst sources for information on distortion. They seem to be aware of the existence of only one type, pincushion. They treat it as a defect rather than a design choice and they use a subjective and unreliable method to "measure" it.

Henry

Click to expand...

Thank you, Henry, I think you are absolutely right.

Canip