[kkx]

Hi,

I just realized that if I choose a PK/A mount UWA (or any PK/A lens), for my K-5, I will not be able to use it on the 5D.

The aperture level will block the mirror.

Some lens have the level protector too, but these can be remove (most of the time, either destructive or not), but the metal level will still cause problem.

I can remove or cut down (I always avoid destructive options when possible) the level for PK/M lens, but to loose the auto aperture function is a pain.

I prefer A lens when I use my K-5, so much easier and I have correct exif.

Apart from PK/M, M42 and adaptall lenses are the one two that I will have no problem sharing.

This is bad news for me. Was really looking forward to get more PK/A lenses (UWA or others).

Do anyone have experience on this? Can I file down the level a bit (just enough avoid the 5D mirror, but still enough to engage the aperture mechanism in the K-5 body?

If I have access to the correct machine/tools, I could make my own PK/A to EOS adaptor, that rotate the lens 180 degree from what the current common PK/A to EOS adaptor does. To place the aperture level on the bottom right conner of the EOS mirror box instead of the top left conner. I did a simple test, you just about able to clear the mirror without any mod on the aperture level.

Bummer. If anyone can help I will be really grateful.

-kk

[lytrytyr]

Do anyone have experience on this? Can I file down the level a bit (just enough avoid the 5D mirror, but still enough to engage the aperture mechanism in the K-5 body?

Here's a link for Pentax FA Limited lenses on the 5D:

??????????? | Flickr - Photo Sharing!

Might try contacting Yasunari Nakamura.

[wlachan]

The only worthy UWA for Pentax DSLRs is the DA12-24/4 but it won't work on EOS FF. Just get yourself the Zeiss ZE 21/2.8 for your 5D and leave Pentax for something else.

[selar]

I just realized that if I choose a PK/A mount UWA (or any PK/A lens), for my K-5, I will not be able to use it on the 5D.

Sigma 14mm F2.8 EX Aspherical Rectilinear Lens Reviews - Sigma Lenses - Pentax Lens Review Database

Was also made in Canon mount (with USM), so you might want to go the other way, i.e. buy in Canon mount where FF is available.

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Last edited by selar; 07-22-2012 at 04:37 PM.

[ChipB]

You might also consider the Tamron Adaptall-2 SP 17mm lens - it's got mixed reviews, but you can use it on either platform. Don't know about EOS, but you can get an Adaptall-2 PK/A adapter so would have metering on your K-5.

There happen to be two on eekbay right now - one with an EOS adapter.

Side note: I have a LOT of Tamron Adaptall lenses and have yet to be disappointed, but I've never used the 17mm so can't comment on it.

[kkx]

It is true that adaptall is the most convenient to share between the two system.

I will get full PK/A functionality with a PK/A adaptor (already have one with a 90mm macro).

So, I have decide to try out the Tamron 17mm first. One is on its way, should be here next week.

As for the other suggestions, thanks. I will keep them in mind. With all the limitation, maybe I should give up about sharing lenses between K-5 and 5D2.

Trying to aim at different usage for each system might be a wiser thing to do. Still trying to figure this things out.

Thanks for all reply, really appreciate it.

-kk

[kkx]

Unfortunately a Zeiss lens is just too expensive for me at the moment. I wish I can try it out. it must be very good on a FF body.

[kkx]

Here's a link for Pentax FA Limited lenses on the 5D:

??????????? | Flickr - Photo Sharing!

Might try contacting Yasunari Nakamura.

Very nice result using FA limited lenses on 5D. These sort of result is what encourage me to try multiple systems. But I think (maybe I miss something) Nakamura modify the lens to be use on 5D only. If I were to use them on K-5, these lenes will most likely be acting like a PK/M lens (I have mod my K-5 with a shorted A-pin).

-kk