I've got both, myself. Here's my two-cents' worth:

Image quality is about the same. The KP has higher pixel density, so I think they come out about even in that comparison. But the K-1 is going to be able to make bigger prints just because it's wider and taller.

K-1 has "astrotracer" built-in. KP can do it but it takes an extra-cost attachment.

K-1 has two card slots, KP only one (which affects your ability to proactively guard against the failure of a memory card, since K-1 can write to both or split JPEG off from raw).

I use battery grips with both, and the KP's optional ability to use the K-1's battery in the grip is a plus as to time to shoot prior to battery death. Never had a problem with either, though.

The K-1's limited to FF lenses as a practical matter, while the KP can use either FF or APS-C lenses.

The KP is lighter in weight, and to my hands, better ergonomically (esp. w/the interchangeable grips).

I don't use the green button, make movies, or do continuous "flap-flap-flap-flap-flap" sports/bif shooting. I think the K-1 is more flexible and adaptable, because the KP is basically a subset of the K-1's functionality. I like the K-1 best for portraiture and landscapes. The KP is terrific for macro & street shooting.

[gaweidert]

When I got my K1, I pretty much put my K3, K5 and K5-IIs aside. The KP has always intrigued me but not enough to open the wallet to get one. Of my APSc cameras only my K3 gets out and then rarely. The K5 is gone. I certainly have no problems with the images made wit the KP that have been posted on this site. It is a very capable camera.


When I got my K1 the images amazed me. They have a certain something to them. You can crop to your hearts content. Awesome dynamic range. I am awaiting the new Pentax APSc model to see what improvements Pentax has built into it. I do have money set aside if it will fill a need. It may become my wildlife and action camera. My only real problem with the full frame models is the shutter shake issue and this is not unique to Pentax.

[fs999]

I purchased a K-1 because the KP didn't come out at that time

[Papa_Joe]

Last year I decided to move on from my K10D, as it had developed a constant backfocus.

Initially I wanted to buy a K1, but after trying one I decided to buy a K-70.
The K1 is a wonderfull camera and it works well together with legacy lenses. But I found it to bulky. After trying it for half an our my wrist hurt for the rest of the day. I then knew I would still need a APS-C camera. I really did like the KP, but for me it's features were not worth the additional pricing over the K-70 especially as I was not sure if I would stay with Pentax.


I am very happy with the image quality, autofocus and all the other technical features of the K-70. It's a bit to small, but that is ok.
But I really do not like it's user interface. You have to look onto the screen and into the menu every time a setting has to be changed. I thus would now recommend getting a camera with shoulder display, if you are used to one. The KP is not better then the K-70 in this regards.

Why did I want a K-1: Better ergonomics (the K-70 has proven this point right). Still visible better IQ in higher ISO. Open aperture is really a different thing on full frame. Use a 2.0/35 mm or a 1.7/50 mm on the K-1 and watch the difference. I bought a 1.4/35 for my K-70 and it comes really close, but it's not the same.

Why did I prefer an APS-C camera: Better handling. Price. Only 24 MP and that is still to much for my usage. I would prefer a 24 MP full frame instead of a 36 MP.

I will work my way into the K-70 and then in one year I will think about a full frame again, perhaps it will result in a K-3 II then.

[Ray Pulley]

I was all set on getting the K-1 in the near future once the latest model came out and brought the prices down a bit on the original K-1 but I've recently discovered the most underrated camera of all time, the KP. I've been reading up on it as much as I can but there's not a lot of info out there, not even on Youtube.

I'd like to know what made you decide to get the K-1 over the KP. I'm torn between the two. In the older days (Nikon D700) a full frame offered way better ISO performance but in this day and age the smaller senors do a great job at high ISOs. I know that the K-1 has better bokeh over the KP, but when I travel I bring my FUJI GSW690II and shoot at f/16 so I don't need bokeh. I'm actually selling my medium format cameras because the cost of the film and developing and processing is adding up.

Well, ultimately, image quality is always #1 for me, and the K-1 with the larger sensor is one of the best cameras in the market in terms of IQ.

Otherwise, my holy trio (31,43,77) have always been under-utilized on crop sensors, so now they can get more work where they belong. My Tamron 28-75 f2.8, which had been sitting on my shelf since the film days, is turning out to be a pleasant surprise on the K-1 as well, producing much sharper images than I expected.

Also, the K-1 gives me the best of both worlds where I can still shoot my DA lenses in crop mode with results roughly equal to the K5, which was pretty good in terms of IQ.

I have a K3ii, so if I were to buy another crop camera, it would be whatever Pentax comes up with next, assuming it has significant improvements in some areas, especially AF tracking.

[JerzyJ]

I’ve chose K1ii over KP mainly because:
1. Better screen, I use it often, love to make landscapes in portrait orientation with a lot of foreground, also easier when doing macro.
2. Battery life, almost two times longer in K1, important for me while backpacking for few days with no chance for charging it. Also less problem with changing battery in bad weather. When you add cost and weight of spare batteries and grip for KP, K1ii with 200€ discount was easy choice.
3. Astro tracer- always wanted to try it out!
4. Got a bit scared when few people started to complain about KP weather sealing, WR is the most important Pentax feature, however I always considered it as last resort and tried not to test it. I protect my camera with extra gear.
5. Image quality and resolution, I’m awful pixelpeeper.

[PentaMiCL]

I am currently in the phase of only wanting to use one focal length and in this state, it's more about which camera the best lens can be mounted on. I love my K-70 (and I have no doubt I will love the KP more) but the K-1 would let me use a more attractive option for the focal length (35mm equiv.) I want. So... if you have a similar situation, maybe you can pick the lens you want to use the most first and automatically have your answer. Just a thought.

[bilybianca]

My version of an answer:
When I bought my first digital Pentax, I already had some of the "Green Star" lenses. When I realized that my shining new *istDS had a sensor smaller than the old film negative, I decided to continue buying "full frame" (funny, in the film era we called 24X36 small image cameras, as opposed to 6X7. 645 was "medium format") because I was convinced that all manufacturers, including Pentax, would release full frame when sensor prices had gone down a bit.
What a wait! 10 years! And meanwhile they released the camera I dreamt of, the K5. I have, use and adore that camera, but I also preordered the K-1 as soon as I had tried the only one available in Scandinavia.
To this day I only have one DA lens, the 14mm. But it sits idle on the shelf.
I'm not pixelpeeping, or get into lengthy discussions about the miniscular differences in tisortat. But I enjoy the feel of both my camera bodies. The *istDS has retired and is now a museum item on display in my study.

Kjell

[universalfocus]

I have a K-5 and had a K-50. I thought about getting first the KS-2, then the K-70 or later the KP, but I didn´t buy any of those and went for the K-1 instead, because of the dual SD-Card slots, the bigger battery (same as in the K-5), the larger grip and better balance with bigger lenses. I really like my K-5, but a follow up for the K-3 wasn´t there then, and the K-3 didn´t seem up to date anymore when I had the money for a new camera (I get a new camera about every 5 years, but 1 or 2 new lenses each year).

[kiwi_jono]

I got the K-1 primarily because I wanted to use my FA lenses with their native field of view and in any case the KP did not exist yet. The FA limiteds are fantastic on the k-1 and certainly it a big step up from my k-5 and DA limiteds. Personally I have found even the DFA 28-105 is surprisingly good given the sharpness even with 36MP resolution (and plenty of possibility to crop and scale images) - obviously not the best lens for shallow depth of field though. The k-1 also feels the perfect size in my hands
But that all said the k-p looks like a good around compromise and makes for a more compact system. I'm happy with the size of the k-1 but because of the FA limiteds.

[31 Limited]

I too have both. K1 was purchased first because I had all the legacy lenses I would ever want, and it has not disappointed. Also, the KP had not been released yet. I came from the K5iis and the size of the K1 was at times just too much for what I wanted all the time. I got the KP to supplement the K1, but I find I use the KP more than the K1. Still love both.

[MJKoski]

8K. Since D800E I have demanded 8K resolution from my main camera system. I have K-1 for full-spectrum photography, be it infrared, UV or everything (KolariVision IR-Chrome filter). Infrared makes full use of pixel-shift where I can have clean red channel. Large sensor brings light collection advantage and it really counts in infrared.

Other than that, I use Zeiss .ZK and converted .ZF lenses a lot. And print very large.

Nothing really wrong with KP and certain limiteds, for example 35mm ltd macro. I used that combo a lot.

[noelpolar]

Definately K1 over KP any day of the week as a hobbiest thing...... unless one has some specific reasons for the KP. Enough info above to work out if you have any such reasons. Anyway.... get a K1 and see for yourself..... no pentax lover, on their death bed, will regret not getting a KP..... but 1 in every 10 will regret not having owned a K1. This has been researched..... results currently being peer reviewed before publishing..... people on their death bed are notoriously unreliable at the peer review stage..... probally should not have relied on them for the review.....

[Rondec]

So, it has to be understood that the K-1 came out quite a bit before the KP, so for many of us it wasn't one versus the other. But I was waiting for full frame -- partly for performance (particularly low iso dynamic range) and partly because of the lenses I already owned. I already owned the DFA 24-70, 70-200, FA 31/77, DFA 100 macro and DA *55. Many of those lenses are "nicer" on full frame. That is to say, the FA 31 is an average-ish 50 mm lens on APS-C, but a really fun wide angle on full frame, the FA 77 is a nice portrait lens on both APS-C and full frame, but the working distance is a little bit long on APS-C.

Honestly, I would choose based on what lenses you own and plan to buy. I think you can be satisfied and make great images with both.

[savoche]

I guess I wanted the larger sensor. Wanted, not needed. I had quite a few FF lenses already. Besides, the K-1 uses the same batteries as my K-3. And I like having dual card slots. The sensible choice for me would still be a KP, though. The even more sensible option would be to just stick with the K-3 - as I had planned to do until a used K-1 showed up at the right price and at a time when I thought I deserved something special