[Wired]

Heres a round of questions that may raise new questions:

1) Are you planning on using Legacy glass or new glass?

2) If using Legacy glass, why do you want a ultra-high resolution sensor where the glass may not be able to keep up?


Nikon users ran into this same problem with the D800 series, the old D series glass wasn't upto the task of handling the higher resolution of the D800. Even the 135mm f2.0 DC has issues rendering under the D800 unless everything is technically perfect.

I think that if we get 36, 42, 50, 70, 99mp cameras that the minute one tires to mount up M series or FA series glass they will be seriously disappointed in what they see. Leading to many people dismissing the cameras as a bust,

[y0chang]

We have no idea what sensor they are gonna use. What I would like to see is...a 24 or 36 mp BSI sensor. We would could get 10 fps or better with a giant buffer. This would fit the pentax mantra and make the FF a K3FF. Since pentax used a odd 20 mp sony sensor in the ks series, this is within the realm of possibilities. My guess is right now they are developing multiple options and that is why they aren't announcing the final specs. Also Sony hasn't even produced production models of the sensor, and the step between concept and production is a pretty steep when you are talking about the technology involved.

[repaap]

Heres a round of questions that may raise new questions:

1) Are you planning on using Legacy glass or new glass?

2) If using Legacy glass, why do you want a ultra-high resolution sensor where the glass may not be able to keep up?


Nikon users ran into this same problem with the D800 series, the old D series glass wasn't upto the task of handling the higher resolution of the D800. Even the 135mm f2.0 DC has issues rendering under the D800 unless everything is technically perfect.

I think that if we get 36, 42, 50, 70, 99mp cameras that the minute one tires to mount up M series or FA series glass they will be seriously disappointed in what they see. Leading to many people dismissing the cameras as a bust,

I will be really sad if my takumars and helios will not be perfect on new FF!
(Edit: I forgot smiley)

BTW there have been great examples from member pinholecam, with his sony A7...so I would be quite comfident that some FA lenses will be just fine if even older lenses have been so.

I'll buy couple modern Zooms and primes along new pentax FF. But I think that I'll have fun with most of my lenses that I own already. With good enough quality.

---------- Post added 06-29-15 at 16:59 ----------

New lenses and release of 'complete' set at once would sound like a proper reason fir delay.

[D1N0]

2) If using Legacy glass, why do you want a ultra-high resolution sensor where the glass may not be able to keep up?

Maybe corner performance especially at wide angles. But aberrations will be relatively smaller on FF and pixel size is bigger than (with 24mp) and the same as the K-5 with 36mp. A 42mp sensor would mean the same pixel size as about 18mp on aps-c. Resolution of good legacy glass will not be more of a problem as it is on the K-3.

[Wired]

Maybe corner performance especially at wide angles. But aberrations will be relatively smaller on FF and pixel size is bigger than (with 24mp) and the same as the K-5 with 36mp. A 42mp sensor would mean the same pixel size as about 18mp on aps-c. Resolution of good legacy glass will not be more of a problem as it is on the K-3.

what about resolving power?



at the end of the day it doesn't matter. Us forumites get too caught up in the technical all the time. We just need to get out and shoot

[reytor]

My great great granmother told me last night (while in sleep) that the Pentax FF will not use Sony sensor! Pentax engineers went to Samsung and they got the 2018 version of their xfpdbflicp (extrafinepixeldensitybackandfrontlitinchipprocessing) sensor! :O

[D1N0]

what about resolving power?

My point is that a lens needs less resolving power on a FF when the sensor has the same number of pixels as an aps-c sensor. Because the pixels are larger, which makes them easier to resolve. Thus the true test for a lens is not number of MP but pixel size in micron.

[Wired]

My point is that a lens needs less resolving power on a FF when the sensor has the same number of pixels as an aps-c sensor. Because the pixels are larger, which makes them easier to resolve. Thus the true test for a lens is not number of MP but pixel size in micron.

the math hurts my head. I'll just go back to shooting

[sholtzma]

When one says "older lens designs" might not work so well on the FF, what does that mean? There were redesigns along the way, right? K series is not FA series. So, is lumping all older designs together fair? Could K series lenses not perform as well, but FA series (or at least some FA) perform well enough?

[D1N0]

Depends on the lens. Most newer F and FA have better coatings than older designs, but many FA/F zooms are mediocre at best. Just look at the lens reviews. Lenses that are rated well on aps-c will most likely do well on full frame. There is a big unkown and that is their edge and corner performance.

[reh321]

My point is that a lens needs less resolving power on a FF when the sensor has the same number of pixels as an aps-c sensor. Because the pixels are larger, which makes them easier to resolve. Thus the true test for a lens is not number of MP but pixel size in micron.

the math hurts my head. I'll just go back to shooting

You are right. Conceptually this is not easy. You almost have to experience this for it to become real. As an example, I use an adapted Sigma 70-300mm lens on my Q-7. I'm getting reasonable pictures, but they are not sharp 12 Mb pictures, where each pixel uniquely reports one precise area. Why? Because that Sigma lens is designed to hit a larger target, where there is a certain distance between the pixels. The pixels on the Q-7 sensor are closer than that, so in some sense a ray that would hit a single pixel on an APS-C sensor hits several neighboring pixels on the smaller Q-7 sensor.

[jeff knight]

Depends on the lens. Most newer F and FA have better coatings than older designs, but many FA/F zooms are mediocre at best. Just look at the lens reviews. Lenses that are rated well on aps-c will most likely do well on full frame. There is a big unknown and that is their edge and corner performance.

You are dead right about edge and corner performance being the "big unknown" when transitioning from a crop camera to FF. I suspect that there will be more than a few people who discover that their favorite lens is not so good across the frame.

As for looking at lens reviews... We have a great review database here, but some of it is very flawed. For example, look at reviews for the Pentax F 28-80. 80% of the reviews on that page are not even for the lens pictured, but for vastly inferior uncoated kit lens version. That page is a joke and should be fixed! There are many 3rd party lenses with deceptive reviews. How can you really judge the quality of a lens with just one copy? Reviews can be very helpful but I endorse the find-out-for-yourself school of thought.

[reh321]

You are dead right about edge and corner performance being the "big unknown" when transitioning from a crop camera to FF. I suspect that there will be more than a few people who discover that their favorite lens is not so good across the frame.

As for looking at lens reviews... We have a great review database here, but some of it is very flawed. For example, look at reviews for the Pentax F 28-80. 80% of the reviews on that page are not even for the lens pictured, but for vastly inferior uncoated kit lens version. That page is a joke and should be fixed! There are many 3rd party lenses with deceptive reviews. How can you really judge the quality of a lens with just one copy? Reviews can be very helpful but I endorse the find-out-for-yourself school of thought.

The "lens reviews..." pages you pointed to are professional ones, not the uneven amateur contributions. Of course, there is always a possibility that they got an unusually good or bad lens, but I have always found them to be useful. I would certainly always look at those before risking my own money on one.

[repaap]

The thing is, that lot's of older lenses will be good enough. but to pixel peep and all of that there lies a problem, which occurs already with our APS-C K-3 and previous models. In some peoples heads. Disappointments will happen anyway. But is that quality enough, we will have to see, and think that, what is enough...

[sholtzma]

So, perhaps as we move forward, we need different kinds of evaluations of lenses: will they work well on a pre-K5 model? Will they work well on a K-5? A K-3 series? A full-frame series?