[ManuH]

Here's a quick example of that - the following shot was taken as I was just standing over my little guy, at 35mm, f/1.8 on FF. Now, this looks just like a typical shallow-DOF shot, but in fact to get that exact shot on aps-c you'd need to be shooting a 23mm f/1.2 lens wide-open - and they don't make one of those.

Yes, fast wide angles are one of the good reasons to want FF. The fastest wide angle for pentax is the FA 24mm f/2. That's not wide enough anyway. Below 24mm, they're all f/2.8 min. On FF there are 24mm f/1.4, an APS-C would need to be 16mm f/0.9 ... And even 16mm f/2 doesn't exists. It means a full 3 stops advantage for FF.

[rparmar]

Believe me, they are sharper than on APS-C

I was becoming convinced by your reasoning, but none of your evidence shows what you hope it will. Oh, and random posts saying "LOL" do not constitute an argument. Neither do references to the Titanic.

[Clavius]

I was becoming convinced by your reasoning, but none of your evidence shows what you hope it will. Oh, and random posts saying "LOL" do not constitute an argument. Neither do references to the Titanic.

I agree with rparmar.

With most FF images I've seen in this thread I keep thinking: "Nice image... Just a pity the DOF was selected way to thing though."

[Emacs]

I was becoming convinced by your reasoning, but none of your evidence shows what you hope it will. Oh, and random posts saying "LOL" do not constitute an argument. Neither do references to the Titanic.

You seem to be too sluggish. The only things that were completely objective in this thread are graphs about lenses resolution and the explanation why the lens with larger focal length usually have higher resolution figures at the common part of the frame with the one with lesser FL.
These two reasons would be enough for me to be convinced FF lenses are usually superior over their APS-C counterparts.

[Rondec]

Yes, fast wide angles are one of the good reasons to want FF. The fastest wide angle for pentax is the FA 24mm f/2. That's not wide enough anyway. Below 24mm, they're all f/2.8 min. On FF there are 24mm f/1.4, an APS-C would need to be 16mm f/0.9 ... And even 16mm f/2 doesn't exists. It means a full 3 stops advantage for FF.

I suppose. This is one of those situations where it is a question of what you want. I seldom shoot really wide and particularly with regard to portraiture, I find that the distortion these lenses tend to produce makes them not conducive to making people look their best. This is true for both full frame and APS-C cameras. When I shoot wide angles, it tends to be landscapes and I stop down to get things in focus.

There is an art to narrow depth of field photography and most people don't have it. I don't think I have it and tend to look at my images shot this way and wish that I had stopped down a little more and gotten everything sharp.

[jsherman999]

I agree with rparmar.

With most FF images I've seen in this thread I keep thinking: "Nice image... Just a pity the DOF was selected way to thing though."

Keep in mind that with FF, you can always stop down to match the aps-c DOF - you can't always go the other way.

Really, no-one should need a thread like this to 'teach' themselves about FF - all the info is available out there on the web in much better form. If you don't see the potential benefits (or drawbacks) by understanding equivalency and what that would mean to you as a shooter, which often comes from more shooting experience, then you're stuck in this mildly confrontational "show me why it makes a difference!" mindset in threads like this.

It is what it is: 1.3 stops more DOF control at equivalent FOV/DOF, one to three stops better ISO performance depending on body matchup, bigger viewfinder, more forgiving on lenses, and then peripheral things like much faster AF. It's going to be up to you as a shooter to determine if those things are useful to you, how/when you'd use them, and then how much you'd pay extra for them.

Simple.



.

[rparmar]

I'm not sure how this moved to a 'what pros want' comparison

Fair enough. Maybe I can make my point a little clearer. It's all about being pragmatic and playing to the Pentax strengths, which I see as being compact high quality primes, excellent ergonomics and weather-sealing at a reasonable price point. If you want the biggest system, best pro support, longest glass, fastest AF, highest resolution, etc. then you should be looking elsewhere... and paying the appropriate price.

Likewise it is obviously not a Pentax strength to produce the fastest lenses, because they've released only one faster than f/2 in the digital era (IIRC). Now, one can rail against this reality, but I prefer they stick to their strengths. Otherwise the brand will disappear in short order.

There are very few reasons and very few shots that require faster than f/2.8 on full-frame, call that f/2 on APS-C. Faster lenses are severely optically compromised, since aberrations increase by a factor of nine for every stop faster. In order to battle that you need bigger and more expensive lenses, which is not something most Pentax users are going to be enthusiastic about. Anyone want a system full of 5K primes (like Leica)?

I find that odd, I'm often scrounging for every bit of light I can get in a lot of indoor situations. f/1.8, 1.7, 1.4 and even 1.2 are welcome to me, with regards to both shutter speed and subject isolation.

Well, me too, but I am also struggling to get shots in focus. Faster than f/2 and the law of diminishing returns sets in, since the technology in place cannot accurately focus at wider apertures than that. Everyone knows the Pentax fast 50s that top out at f/1.8 are better than those that go to f/1.4. The nicest rendering of the bunch is the FA43 Limited. And the sharpest 50mm is the slowest.

Oh yes, I own two f/1.2 lenses, because I do like experimenting. But my argument in this thread has little to do with my own preferences, only what I think is wisest for the company. Perhaps that was not obvious.

By the way, I deny the claim that you need faster than f/2 for subject isolation. That depends on a host of other factors that you, as photographer, should be controlling. Likewise you don't need faster than f/2 for shutter speed, now that high ISOs are commonplace.

I have stated very clearly I would love a full frame or medium format camera. I have never once argued against 35mm as a superior medium to APS-C. But since I cannot even afford a K-5 I'd be presumptuous to call for a camera I can afford even less! Yet certain forum posters expect Pentax to bankrupt themselves delivering hardware they'd never actually buy. Whether that's a $4K full-frame or a 600mm lens.

What I really want is very fast AF lock, very good ISO performance, followed by good DR and more DOF control.

So this begs the question: What's wrong with your D700?

[mccarvindh]

So this begs the question: What's wrong with your D700?

Cannot mount the Pentax Limiteds?

[rparmar]

The only things that were completely objective in this thread are graphs about lenses resolution and the explanation why the lens with larger focal length usually have higher resolution figures at the common part of the frame with the one with lesser FL.

I made no statement about being "objective" so I cannot understand the relevance of your response.

These two reasons would be enough for me to be convinced FF lenses are usually superior over their APS-C counterparts.

You are confusing the sensor with the lens. The FA77 is the same no matter what sensor it is on. It doesn't magically change its properties. Maybe what you prefer is the difference between film and the digital sensor. But that's a different thread.

By the way, your graphs were useless -- a shame you didn't first consult some English engineers for advice. You failed to hold parameters constant while varying just one. You cannot compare three different lenses on two different sensors and expect the comparison to tell you anything.

You seem to be too sluggish.

I am looking to have my mind changed with evidence, since it's one of the few ways I learn. You seem to disparage this impulse. This says a lot more about your character than mine.

[rparmar]

Cannot mount the Pentax Limiteds?

Likewise a Pentax cannot mount the cheap and excellent NIKKOR AF 85/1.8D, AF 50/1.4S, AF DC-NIKKOR 135/2, etc. Nor any tilt/shift lenses. Etc. Etc.

I suppose by this logic one should buy an MFT camera and a bunch of adapters. Which is what I did, actually! But I somehow doubt the people arguing for a larger sensor would instead go to a smaller one.

[ManuH]

I suppose. This is one of those situations where it is a question of what you want. I seldom shoot really wide and particularly with regard to portraiture, I find that the distortion these lenses tend to produce makes them not conducive to making people look their best. This is true for both full frame and APS-C cameras. When I shoot wide angles, it tends to be landscapes and I stop down to get things in focus.

There is an art to narrow depth of field photography and most people don't have it. I don't think I have it and tend to look at my images shot this way and wish that I had stopped down a little more and gotten everything sharp.

*YOU* don't need FF. But all things being equal FF is obviously better. After all, APS-C is just a crop of a FF sensor. A FF sensor just has to be cropped to do what an APS-C sensor is producing (provided that they have the same pixel pitch and overall performance, the picture will be identical). On the whole FF provides more resolution and more SNR, these are facts yes. But do the differences really matter? Some people are happy with 4/3 or even some high end P&S.

The only problem with FF is that all the predictions of FF overcoming APS-C are still wrong. Canon and Sony are still investing a lot in APS-C. FF cameras release are slow to come. Nobody seems to care and the current hot things are the small mirrorless cameras, none using a FF sensor. Maybe the next Canon/Nikon move will change that but I'm not optimistic at this point.

[ManuH]

By the way, your graphs were useless -- a shame you didn't first consult some English engineers for advice. You failed to hold parameters constant while varying just one. You cannot compare three different lenses on two different sensors and expect the comparison to tell you anything.

Why not? He's not trying to do a fair comparison. He's trying to compare the *end result*. The MTF scores are absolute numbers after all.

[jsherman999]

Fair enough. Maybe I can make my point a little clearer. It's all about being pragmatic and playing to the Pentax strengths, which I see as being compact high quality primes, excellent ergonomics and weather-sealing at a reasonable price point. If you want the biggest system, best pro support, longest glass, fastest AF, highest resolution, etc. then you should be looking elsewhere... and paying the appropriate price.

What many of us have been calling for is a smallish-form FF body with WS to shoot the already-small FA Limiteds and some new optional lenses. This stays with what many see as Pentax's strengths. Also, whatever Pentax does in FF doesn't make their small/rugged/WS strength in aps-c go away.

Likewise it is obviously not a Pentax strength to produce the fastest lenses, because they've released only one faster than f/2 in the digital era (IIRC). Now, one can rail against this reality, but I prefer they stick to their strengths. Otherwise the brand will disappear in short order.

Was this really a strength, or just a choice made from necessity and lack of resources? Additinal K-mount funding from Ricoh could mean slower/smaller DA lenses plus faster, slightly larger FA-style lenses - for both FF and aps-c shooters.

Well, me too, but I am also struggling to get shots in focus. Faster than f/2 and the law of diminishing returns sets in, since the technology in place cannot accurately focus at wider apertures than that. Everyone knows the Pentax fast 50s that top out at f/1.8 are better than those that go to f/1.4. The nicest rendering of the bunch is the FA43 Limited. And the sharpest 50mm is the slowest.

Not sure what the point is there actually or how that ties in. FF allows you to shoot an uncompromised f/2.8 lens for example and enjoy the DOF you'd see at f/1.8 on aps-c. The superb FA 43ltd doesn't become any more compromised on FF, yet it becomes equivalent to a 29mm f/1.2 lens with respect to FOV/DOF. You may not want to shoot it wide-open, but that f/1.2 equiv would be available to you if you did.

Oh yes, I own two f/1.2 lenses, because I do like experimenting. But my argument in this thread has little to do with my own preferences, only what I think is wisest for the company. Perhaps that was not obvious.

For me, it's both, honestly. I think it's going to be even harder to compete at the aps-c price/performance tier than it has been in years past. If Pentax mostly lives there, without a strengthened K-mount, we may be in trouble. IMO.

By the way, I deny the claim that you need faster than f/2 for subject isolation.

Depends on the situation and what you're going for.

Likewise you don't need faster than f/2 for shutter speed, now that high ISOs are commonplace.

I often do. You may not for what you shoot, but I like having a lot of stops available in my options bag, gained from aperture and/or ISO.

I have stated very clearly I would love a full frame or medium format camera. I have never once argued against 35mm as a superior medium to APS-C. But since I cannot even afford a K-5 I'd be presumptuous to call for a camera I can afford even less! Yet certain forum posters expect Pentax to bankrupt themselves delivering hardware they'd never actually buy. Whether that's a $4K full-frame or a 600mm lens.

The single best argument against FF is the cost, even more than the size, IMO. You'll get no argument from me there, it's fun to shoot, not fun to pay for

So this begs the question: What's wrong with your D700?

It doesn't mount the FA Limiteds. (only half kidding.) EDIT: someone beat me to it.

Seriously though, I would have rather bought a Pentax FF if it even came close to matching up. It also represents to me yet another missed opportunity for Pentax, a continuation of a kind of lack of institutional will that's led to Canon/Nikon surging ahead of them in the past 30 years.

Canon and Nikon hold no magic, they've just invested more and took more risks over the years. Now maybe Ricoh can really bring Pentax fully back to the table. My hope.



.

[rparmar]

Why not? He's not trying to do a fair comparison. He's trying to compare the *end result*. The MTF scores are absolute numbers after all.

Please read what I wrote again. You know, the bit you quoted, where I pointed out it was not a fair or scientific comparison in any way.

[rparmar]

Seriously though, I would have rather bought a Pentax FF if it even came close to matching up. It also represents to me yet another missed opportunity for Pentax, a continuation of a kind of lack of institutional will that's led to Canon/Nikon surging ahead of them in the past 30 years.

Canon and Nikon hold no magic, they've just invested more and took more risks over the years. Now maybe Ricoh can really bring Pentax fully back to the table. My hope.

If Ricoh can bring out a Pentax 35mm sensor camera at a reasonable price without sinking the brand, great! But my evaluation is that a company with such small market share would only lose money on this attempt.

Canon and Nikon have not taken more risks. They simply got further ahead with the whole AF thing and then solidified their position through not taking any risks whatsoever. It's a perfect example of a market tipping point. Pentax have as much chance of taking them on as Beta did of clawing back from VHS tape. The market is not kind, fair, or logical. It rewards brute force far more than it rewards innovation.

And with that I think I've said everything I can on this subject. Until the next similar thread.