How can the Pentax 40/2,8 be so small?

[jpfisher]

Originally Posted by BlackXList

Almost sliding off topic here, has anyone tried that Canon 40mm? opinions?

Super small, very sharp, and relatively cheap. ($150 at B&H right now!)

The only downside is the focus-by-wire design--if the focus motor goes, it's a dead lens. If I owned a Canon EOS system I'd buy one in a second.

I've also shot with the Pentax 40mm XS (bundled with the K-01) a little bit and more extensively with the 43mm Limited. The latter is one of my favorites--fast, compact, and it feels like a real lens--I'm looking forward to using it on full-frame digital via an adapter + EVF when the "M" is released.

The latter doesn't do me much good on film (my Pentax bodies are too old to control the aperture), but was happy enough with its performance on APS-C. Glad to know what it can cover a 35mm frame.

[ruby.monkey]

Originally Posted by jpfisher

Super small, very sharp, and relatively cheap. ($150 at B&H right now!)

The only downside is the focus-by-wire design--if the focus motor goes, it's a dead lens. If I owned a Canon EOS system I'd buy one in a second.

I've also shot with the Pentax 40mm XS (bundled with the K-01) a little bit and more extensively with the 43mm Limited. The latter is one of my favorites--fast, compact, and it feels like a real lens--I'm looking forward to using it on full-frame digital via an adapter + EVF when the "M" is released.

The latter doesn't do me much good on film (my Pentax bodies are too old to control the aperture), but was happy enough with its performance on APS-C. Glad to know what it can cover a 35mm frame.

Are you referring to the 40mm XS? Because the 43mm (like all the FA Limited lenses) offers manual aperture control.

[jpfisher]

Originally Posted by ruby.monkey

Are you referring to the 40mm XS? Because the 43mm (like all the FA Limited lenses) offers manual aperture control.

Yep--the latter "the latter" should read "the former" -- my bad!

[titrisol]

The Pentax 40 is a great lens IMHO
It is a 5 lenses, 4 group design....


I guess 40mm is a natural length that can be a pancake, but it is not the only one

The Tessar was a pancake of its time....

[tunalegs]

Originally Posted by titrisol

The Pentax 40 is a great lens IMHO
It is a 5 lenses, 4 group design....


I guess 40mm is a natural length that can be a pancake, but it is not the only one

The Tessar was a pancake of its time....

TBH I don't think "pancake" has any technical meaning. It is just a nickname for lenses with very short barrels. Many of the older CZJ Tessars had a built in hood, so the barrel was not any shorter than used on faster lenses, but the exact same glass also came in short "pancake" style barrels at various other points in time. When double gauss designs became the standard for SLRs, it was typical to put triplets and tessars into large barrels to make them look more modern. Half the length of this Steinheil lens is just a built in shade for instance:

Steinheil Edixa-Auto-Cassaron by berangberang, on Flickr