[JensE]

The huge difference is that the K1 will focus instantly and accurate in situations the K5IIs would not. It makes a ton of difference in the number of keepers. Low light is a whole new experience with the K1 as well as shooting wildlife in brushy situations where the K5IIs tended to hunt for the focus subject.

Definitely, and especially when using continuous AF in low light. I was surprised how well it tracks in a gym even with the camera-driven D-FA100WR lens chasing wild players instead of wildlife.

[Fenwoodian]

What I find is an even bigger difference than full frame vs cropped frame is "with or without AA filter".

I see a HUGE and very visible difference. That's why I will never again shoot with a camera with an AA filter.

[audiobomber]

Color Depth, Dynamic Range and ISO performance all deteriorate when you use the K-1 in crop mode This is easily seen be reviewing DXOMark results, or by cropping any digital image.

[Rupert]

Color Depth, Dynamic Range and ISO performance all deteriorate when you use the K-1 in crop mode This is easily seen be reviewing DXOMark results, or by cropping any digital image.

That wasn't really the question, was it? We are comparing a crop shot to a crop shot. So what you are saying is that APS-C is inferior, which is not necessarily a true observation outside of the laboratory.

All crops are in some degree inferior to their original file size.......this is not exclusive to the K1 or any other camera made that I am aware of?

Regards!

[audiobomber]

That wasn't really the question, was it? We are comparing a crop shot to a crop shot. So what you are saying is that APS-C is inferior, which is not necessarily a true observation outside of the laboratory.

All crops are in some degree inferior to their original file size.......this is not exclusive to the K1 or any other camera made that I am aware of?

Regards!

You're right, I misinterpreted the question (it seems that others did as well):

"If you used a lens for APS-C cameras in the crop mode on the K-1, do you still get the same Color Depth, Dynamic Range and ISO performance that you get with it in the full-frame mode?"

The correct answer would be "Yes, everything is the same". The only difference would be in the amount of vignetting.

[Tan68]

Remember, the reason equivalists say APSC is so much inferior is because they insist on forcing the APSC frame to fit the FF (in terms of FoV and DoF) and only compare after this. And that gives APSC a massive disadvantage and makes it look worse by comparison.
...

The equivocal people do insist on matching field of view and depth of field.. Whether I equivocate or not, I agree. The picture is what matters and whatever-subject is what interests me so why shouldn't DOF & FOV & perspective be the same? Matching these when comparing across formats is the definition of a practical evaluation :^)

If we are comparing APS-C & FF, I might have to stop down the FF to get the same depth of field. I would have to raise ISO to get the same image brightness... I leave shutter alone because the speed I have chosen might be important to control motion blur. Often I am using the slowest shutter I can hold by hand.. either way, ISO goes up for the same picture.

In some cases, I don't expect to gain much advantage from the K-1. I like to take pictures in dim interiors. If I am constrained by shutter speed and I already have narrow enough depth of field with APS-C (function of exposure & not artistic blur), then things will be a wash as I close the K-1 aperture and raise ISO...

The advantage I expect to get from the K-1 would be using my lenses stopped down a bit for the same DOF. The lenses should perform better than they do nearly wide open on K-5.

I expect there to be an advantage where I am not constrained by shutter speed (for instance, stop K-1 down for same DOF as with K-5 and am able to slow shutter rather than raise ISO)

I expect there to be more options for composition. I don't carry many lenses and know I can crop away any advantages the K-1 would have and end up with the same performance as my K-5

[Gimbal]

If you don't use the entire sensor, you will not get the entire performance. It's that simple.

[Tan68]

If you don't use the entire sensor, you will not get the entire performance. It's that simple.

I agree with Audiobomber and Gimbal

[normhead]

My understanding of dynamic range is it's the relationship between the darkest and lightest part of the picture. So with 15 EV if you darkest part of the pictures was 5 lumens, the brightest part would be 5 to the 15th power lumens.

So unless I have this concept wrong it would be un affected by the size of the sensor. A two pixel sensor where one pixel was 5 lumens and the other 5 to the fifteenth power, would still have range of 15th EV would still have a DR 15 EV even though it was minuscule.

Same with ISO and colour depth. These are characteristics of the camera system that are not dependant on the size of sensor.

The only thing you can miss out on is some resolution. But when what you're talking about is a 2 times oversample compared to a 4 times oversample, even then the affects of more resolution are probably imperceptible. It has never been established exactly where it does become perceptible. A 20x30 inch print, 30x40 inch print? Most of us suspect that you took a K-5 image and printed it at 100 DPI, ( 60 inches y 40 inches) and a K-1 image and printed it at the same size, no one has actually demonstrated that the K-1 image would be preferable from more than a foot away.

Yesterday Tess and I ended up shooting pretty much exactly the same scene. Me with a K-1, her with a K-5. We used the same lens and field of view as well. DFA 28-105 her shooting at 37mm, me shooting at 58mm from within 20m of the same spot.

SO I'm going the other way. I consider it to be irresponsible to tell someone a K-1 images is the best image, until I see the parameters that verify that they have a clue what they are talking about and not just speculating. There is for sure a theoretical difference, but when does that difference become real world? I've never seen the question answered.

To me, all this stuff about FF being better is like discussing the size of bacteria and trying to extrapolate. If one bacteria is 10 times the size of another one, which one is more likely to cause a flat tire on your car if you run over them both? (OK that might be a bit extreme, but it's a demonstration of a principal.)

The two images.




There's been a lot of speculation that you gain something using the K-1 image. I'm going to go out on a limb here and say, until I see a verifiable demonstration of that, I'm going to declare that the difference is meaningless.

On my 2700 by 1600 inche screen they look identical, on her 3800 by 2000 pixel screen they look identical. Where is this magic point at which the K-1 advantage is demonstrable? Until that has been established, people who say the K-1 is better are just speculating, and misleading folks. It isn't better on a 3800x200 screen. Where does the "betterness" start? It's an important question, because if in fact it never starts, you can't really say it's better can you?

But here is the killer, at least for me, both images look much better on my low res 103 dpi 27 inch screen, than they do on Tess' 3800 x 2000 221 dpi 21.5 inch screen. The viewing size has more effect on perceived quality than resolution. There are parameters here that have not been explored by the on-line geniuses.

This isn't rocket science. And owning a K-1 has really reinforced what a load of crock folks have been spouting about how marvellous the added resolution between a 36MP file and a 16 MP file is, all these years. For most of these folks, they know there's a difference but they haven't actually seen it. And you haven't seen files like this before, because "everyone needs more resolution" people can't produce an image that demonstrates their point, despite having years to do so.

99% of the people on this forum never produce an image that needs to be more than 12 MP (we have sold 12 MP files printed at 30x20 inches). But 99% of the FF proponents on the forum will try and convince you that they are part of the 1% who might (though it's never been established) need larger files. It gets old.

We sell our prints at 30x20 inches, and my wife sees no need to upgrade from her K-5. There are things I like about my K-1, but it's resolution is grossly under-utilized. I like the camera, that so far that is largely because of the one stop ISO advantage maintaining the same DoF. Not the resolution per se.

The biggest difference in my mind right now, between a K-5 and a K-1 is you have to buy much more expensive lenses on the K-1 to get functionally the same thing.

[Rupert]

It gets old.

Yes it does! This is perhaps your best article on the comparison of APS-C and FF and the most convincing to all but those that refuse to accept either simple or complex logic.

Simply...I have a K1 because my K5IIs fell off a shelf and was badly damaged...so Mrs Rupert bought me a K1. What is demonstrably better is the Superb improvement int he AF system compared to my K5IIs. Amazingly better, in particular in low light or in locking on to the target in brushy scenes. Otherwise, my K5IIs was a wonderful camera!

I agree with Audiobomber and Gimbal

You would be correct if you said "You will not get the entire performance from am APS-C camera as you would from a FF camera." Then read what Norm just posted to understand what that difference is...and it is minimal for the vast majority of shooters.

If a FF camera makes someone feel like a "Big Boy" or an "Elite", then by all means get one! If you are already comfortable in your own skin and happy with what you have, you won't be "amazed" much by the K1. You might however, love that much improved fine AF system in the K1!

Regards!

[Na Horuk]

The equivocal people do insist on matching field of view and depth of field.. Whether I equivocate or not, I agree. The picture is what matters and whatever-subject is what interests me so why shouldn't DOF & FOV & perspective be the same? Matching these when comparing across formats is the definition of a practical evaluation :^)

But why not use magnification and pixel density? By fixating on DoF and FoV, you compensate by changing aperture and shutter, which also affect the image look. Ultimately, its better to accept the two formats are different and to know their advantages, so you can use them in the field. APSC usually gives faster burst mode, smaller camera, smaller lens designs, and is good for telephoto. FF has other advantages, mainly wider angle and bigger pixel sites, and usually has better bit depth (bigger sensor, better hardware to support it). Obsessing over making some numbers fit leads to insane discussion and no results.

But I don't mean to discourage anyone from buying a K-1 or a K-3 or whatever! Im all for people buying as many Pentax DSLRs as possible

[normhead]

But I don't mean to discourage anyone from buying a K-1 or a K-3 or whatever! Im all for people buying as many Pentax DSLRs as possible

I don't know why, but, I'm with you on this." If you'll use it and you have the money , buy it." seems to be my philosophy.

[Rupert]

I don't know why, but, I'm with you on this." If you'll use it and you have the money , buy it." seems to be my philosophy.

You got my vote on it too.....and if your camera falls off the shelf and is badly damaged......and Mrs Rupert offers to buy you a new K1, go for it, you have my blessing!

Regards!

[noelpolar]

mmm... brighter viewfinder, easier manual focus, flippy screen, natural fov for legacy glass, improved af, inprove dr over K3, and low light noise performance are the standouts for me. Extra res is nice when it can be brought to bare. A lot of that is a K3 v's K-1 one thing though..... not APSC v's FF (flippy screen etc)...I still feel the best TC for a K-1 is a K3!

[surfar]

the best TC for a K-1 is a K3!

Pentax make the best teleconverters....Q7/S1