Pentax K to Nikon adaptor?

[eClix]

Hey everyone,

I have been trying to find out if there is something I can get that I can use my old Pentax lenses on my Nikons. I miss them .

[cyclohexane]

I know of Nikon F to Pentax K adapters, but not the other way around...

[dougjgreen]

The problem is, Nikon's flange to film plane distance is 1.04mm longer than Pentax's (46.5mm vs. 45.46mm). So, any Pentax lens that was adapted to fit on a Nikon mount would not be able to focus to infinity

[Nikonfreak]

Here's the real question... What would Pentax K lenses offer a Nikon body that you'd want to use them or adapt them to use on a Nikon body?

Julio

[eClix]

Well the reason I ask is I learned on Pentax, I have lenses, it sadens me that they go unused. They are great lenses, I will alway like Pentax for their simplicity.

[cyclohexane]

What would Pentax K lenses offer a Nikon body that you'd want to use them or adapt them to use on a Nikon body?

Pentax has made (and continues to make) some pretty good lenses, and if one has glass doing nothing, it never hurts to see if there's a way to use it. Personally, I'm always on the look-out for lenses I can jam in front of my cameras if they'll give me a different feel than the Nikkor and other F-mount options.

[Nikonfreak]

I was wondering if there was some lens that Pentax made that Nikon didn't have an equivalent or something that could be used as an instead... kind of like the Canon 200 f/1.8 ... wouldn't it be neat to use that on a Nikon body?

I just don't know how you'd get it to work and if you were just going to go all manual, the Zeiss lenses are out there.

Pentax made some decent gear and it's sad to see them go, but I don't know how much of a market would exist for a Pentax K to Nikon F mount converter even if someone could make one.

Julio

[cyclohexane]

Again, the lens flange problem is why we can't use Canon glass on Nikons, but we can use Nikkors on Canon (the 17-35mm f/2.8D AF-S looks great on the Canon full-frame bodies).

Zeiss glass for most Contax mounts can't fit Nikon, again because of the distances involved. Hasselblad Zeiss does fit with an adapter, and works with matrix metering if you input the data in (as reported to Digital Darrell; I can't substantiate this). I want to pick up a Hasselblad adapter and stick one of their "odd-length-on-35mm" lenses (probably a nice used copy from KEH or eBay) in front of my D2H, but the adapter's fairly expensive. Of course there's the Zeiss ZF stuff, but those are awfully expensive for what you get; aside from the build quality and the long focusing throws (bad for photojournalism), I've seen no evidence that the AF Nikkors are inferior to them.

On the 200mm f/1.8L...

Nikon makes the 200mm f/2.0 VR, which is only 1/3 stop slower, and is considered superior to the Canon lens. The Canon 200 f/1.8 is slow-focusing when compared to modern L glass, lacks IS, and involved toxic glass elements (someone said it contains lead). As far as I know, the Nikkor is sharper, lighter, has better bokeh, is sharper, and doesn't run afoul of environmental regulations for manufacturing. For portraits on DX, it's a bit long... we just need those sensors Nikon's testing that Thom Hogan mentioned as being full-frame to find their way into production Nikon bodies; might as well do it sometime in the near future, as the D2X/S is pushing into diffraction's hell zone where it shows up very clearly due to the photosite size/pitch.

[dougjgreen]

Pentax made a SUPERB 15mm f3.5 lens that I have seen several that pros had adapted to the Nikon mount, at significant expense.

Also, I'd say that the Pentax 50mm f1.4 has always been better than Nikon's.

[eClix]

My uncle has Pentax AF 45mm f1.9, I really like it.

[cyclohexane]

I'd say that the Pentax 50mm f1.4 has always been better than Nikon's.

Well, Nikon's 50mm f/1.4 isn't exactly spectacular; I've got one AIS one, and one of the reasons I'm keeping it is because it's a matched lens to a LE body I own. I didn't see any evidence that it was any better than the 50mm f/1.8 lenses I've been shooting with, except for the 2/3 stop extra light. The best 50mm Nikkor was the 50mm f/2.0.

[dougjgreen]

Originally Posted by cyclohexane

The best 50mm Nikkor was the 50mm f/2.0.

Yep, absolutely. IMHO, the 50mm f1.8 is slightly sharper than these old f2.0 lenses, but the bokeh of the older slower lens is unmatched - I use a home AI'd old 50mm f2 Nikkor-H that I picked up at a camera fair for $10, and it's one of my favorite lenses.

[eClix]

I dunno, I am very happy with my 50 1.4, I think to say 50 1.8 or 1.4 or the older 2.0 is sharper than another is splitting hairs. I have used all three and they are all good glass as far as I am concerned .

[dougjgreen]

Originally Posted by eClix

I dunno, I am very happy with my 50 1.4, I think to say 50 1.8 or 1.4 or the older 2.0 is sharper than another is splitting hairs. I have used all three and they are all good glass as far as I am concerned .

I agree that comparing the relative sharpness of these various 50mm lenses is splitting hairs, but not the bokeh. IMHO, the 50mm f2.0 is much the best of them on that score. The early 50mm f1/4 Nikkor-S also was noticeably lower in contrast than the various f1.8 and f2 lenses.