Any 2* mm f/1.* lens for Pentax?

[emr]

I was just browsing a book I bought about photography of astronomical and weather phenomena. One of the writers mentioned that for night time photography in the woods (dark woods, stars, northern lights and such stuff), he tends to use lenses that are of 20 or 28 mm FL and have apertures starting with "1". That guy is obviously a CaNikon shooter, but reading that part I started wondering if there's anything like that for Pentax. Even older MF lenses.

Is there?

EDIT: SMC Pentax-FA 31mm F1.8 AL Limited comes close...

[RawheaD]

Well, Sigma 30mm f1.4 comes close. Pentax FA* 24mm f2 comes close. Vivitar had a 28mm f1.9, I believe. They also had 24/2 and 28/2.

Vivitar Series I 28mm f1.9 (M42 mount)
http://m42.artlimited.net/lens_detail.php?lid=378

[Marc Sabatella]

Was he talking film (35mm) or digital (APS-C)? If the former, you would need something quite a bit wider to get the same FOV that he was talking about. As for aperture, I would assuem the need for extremely large apertures is not so great in doing those kinds of shots - you'd be shooting on tripod, presumably, and a longer shutter speed would be no big deal unless you were shooting telephoto and star trails became a more noticeable issue. Bbut then, I don't this sort of thing enough to have written a book about it :-)

But taking the advice at face value, the Pentax K28/2 and A28/2 are probably the most reasonable choices in terms of price and available (KEH.com usually has at least one in stock).

[wowtip]

Sigma EX 24/1,8 DG ASP Macro
Sigma EX 20/1,8 DG

[emr]

Thanks, everyone. Marc, that was a good question and it seems he's mainly shooting film these days.

It's interesting that those mentioned lenses that actually fit the description are all third party ones. One would've thought that Pentax wanted to cover such lens type also.

BTW, here's a sample of what he shoots in case you're interested.

[RawheaD]

OH yeah, I'd forgotten about the Sigmas. If you want to do what that guy's doing, you do want fast lenses, and as wide as possible, so I think the Sigma 20/1.8 would be a great choice.

[Blue]

Back in the day, Minolta had a 35mm f1.8 Rokkor lens.

[Taikonaut]

Looks like Canon has 28/1.8....I am wondering why we need such a large aperturen in wide angle lens? I am very happy with my M28/3.5.

[Blue]

Originally Posted by Taikonaut

Looks like Canon has 28/1.8....I am wondering why we need such a large aperturen in wide angle lens? I am very happy with my M28/3.5.

The Minolta would likely be more straightforward to adapt to Pentax mount.

[muustuus]

This could be handy.

K 20/1.4 AL

.muus

[Blue]

Originally Posted by muustuus

This could be handy.

K 20/1.4 AL

.muus

There may be 2 copies of that lens on the entire planet is the only hitch. One has to wonder why the never put it into production.

[Andi Lo]

Originally Posted by Blue

There may be 2 copies of that lens on the entire planet is the only hitch. One has to wonder why the never put it into production.

Why are you so sure on the number two? I would guess that you own one?

[Blue]

Originally Posted by Andi Lo

Why are you so sure on the number two? I would guess that you own one?

I wish I had copy #2. I'm guessing that somebody in the prototyping shop made themselves up a personal copy.

[nater]

Originally Posted by emr

I was just browsing a book I bought about photography of astronomical and weather phenomena. One of the writers mentioned that for night time photography in the woods (dark woods, stars, northern lights and such stuff), he tends to use lenses that are of 20 or 28 mm FL and have apertures starting with "1". That guy is obviously a CaNikon shooter, but reading that part I started wondering if there's anything like that for Pentax. Even older MF lenses.

Is there?

My favorite lens in this category is the Sigma 28mm f1.8 EX Aspherical DG DF Macro. Great lens.