[osv]

As others say... I have used them on a Sony A7r and they look just fine. Which is why I don't really get some of the quips by sites like DPReview where they question how "all these ANCIENT Pentax lenses will hold up" as if some people haven't already been using every single one of them adapted to either full frame mirrorless or even on Canon full frame.

exactly... certainly wrt the fa31, it's already been done on 36mp a bunch of times, i've probably posted over a dozen links on this forum, showing tests of that exact combo.

what ff lenses look like on any crop camera is only part of the picture, you can't rely on that.

[clackers]

Also, DxO stated that some DA lenses are not capable of reaching the full potential of K3 sensor.

Which ones? Link please.

[kp0c]

You'll probably find that 31mm is not wide enough on FF and 77mm is not long enough. (28mm and 85mm are my favorites on film)

I my books the FA43 will be the most useful of the FA Ltds on FF.

Phil.

Same here! The 43mm is such a versatile lens. I use it al the time on my MX (That and the m-28 3.5 travels everywhere with me.) I owned all three of the fa limited and it's the only one I kept. I now have the 21mm, the 43mm and the 70mm. On ff, the 43mm would be similar to the 31mm on crop that a lot of people really like, me included. When I buy the K-1, I'll for sure hunt down a 31mm for landscape and wide angle portraiture.

[Apapukas]

Which ones? Link please.

My bad, they used K5 not K3.

For example 15mm Ltd:

"While its control of distortion is remarkable, its resolution is a bit weak, which is a shame, since it means that photographers will not be able to take full advantage of the Pentax K5’s 16Mpix sensor". (From conclusion)

Pentax SMC DA 15mm F4 ED AL Limited review - DxOMark

[clackers]

My bad, they used K5 not K3.

For example 15mm Ltd:

Well, there we go.

If you're happy with the little DA15 on the K5, you will be on the K-1.

You will have to use crop mode, the pocket rocket doesn't cover the FF image circle.

[Nicolas06]

My bad, they used K5 not K3.

For example 15mm Ltd:

"While its control of distortion is remarkable, its resolution is a bit weak, which is a shame, since it means that photographers will not be able to take full advantage of the Pentax K5’s 16Mpix sensor". (From conclusion)

Pentax SMC DA 15mm F4 ED AL Limited review - DxOMark

We speak of a tiny UWA that among other thing has maybe the most flare resistance of any lens out there. This guy not made for resolution but is still quite sharp on center.

[Conqueror]

It will be interesting to see the FA 31mm stopped down a bit on a K-1 with Astrotracer enabled...

[pinholecam]

what will the 31/55/77 be like on FF?

trying to understand how these might work on FF - what they will be similar to... (the resultant FOV mainly)

imagine border sharpness might be down a bit on the 55 and 77.. may not be a big deal though

I started this Club/Thread exactly because I got very sick of all the nay saying and armchair theories that Pentax "cannot make it".
https://www.pentaxforums.com/forums/122-lens-clubs/247282-pentax-lenses-ff-club.html


The FA limiteds are fantastic lenses even on FF digital.
I use a A7 modified with no AA filter and thin filter mod, so its resolution is pretty good already.
Do note that since the FOV+working distance changes, it CAN change the dynamics of how you use the lens.
I've ended up really liking the 77ltd even more, having the 31ltd become a super versatile one lens (rather than just a niffy 50mm FOV on apsc), and the 43ltd fall out of grace somewhat because what was a 'shyish'/fast 60mm has become a more aggressive 43mm for street photography
So whether it will work better/worse/no-change will certainly depend on the individual.


As to the "accusation" that 36mp will be harsher.
It all depends on how the user uses it.
In fact the context is often wrt either off center wide open or stopped down performance.
Some guys are just not that realistic imo when it comes to the former (how sharp do they want, when a lens is wide open?? )

If its stopped down, most lenses 28mm and up will be no issues.
Old UWA may not be as good off center or on the edges/corners (and filter stack + sensor type plays a role here too).
But then, to be fair, Canon has never had a great UWA for edge performance in its 17-40L; 16-35/2.8L and L vII either. (neither cheap, small nor old lenses)


So in summary, from me, if its 28mm and above and the lens was good on apsc up to the edges (for stopped down work), use with confidence.
Most good lenses when used on FF wide open, center will still be sharp and the off center (rules of thirds area) where most subjects will be placed are still sharp enough.
Only when the lens has a known design characteristic that is mainly central sharpness until stopped down a bit (eg. Sonnar; Biotar, etc designs) will the off center (rule of thirds area be less sharp) wide open.

[Digitalis]

Canon has never had a great UWA for edge performance in its 17-40L; 16-35/2.8L and L vII either.

The Canon EF 11-14mm f/4L is a step in the right direction to remedying this, however at 11mm the degree of distortion correction needed makes you lose a few mm of FL.

[Nicolas06]

From experience, a sensor with more pixel improve overall sharpness more than buying a sharper lens, at least for common range.

In all case having more pixels will only allow to get more details if the lens can resolve it and do not change much otherwise. If a lens was delightful on a 16MP sensor, no reason that suddently the picture like to look crap on a 36MP sensor. At worst, the lense will not leveral aoo the details but in practice, most lenses will.

I agree here this is bit different as the lower magnification of the FF will help the lens outresolving the sensor in the center but that the border performance is somewhat unknown. For most lenses once closed dow this should be no problem.