[rumplestiltskin]

I own a K5IIs and it works fine; no issues. Owned it for almost three years. While I try to resist pixel-peeking, sometimes it gets the better of me and I've been thinking about adding a K-1. But close to $2K is a heavy load to lift. Then I starting thinking that the Fuji X-series do provide a bit better IQ but, OMG, are those lenses costly!

So here's what I'm thinking and I would certainly listen to advice from K-1 owners: I own a bunch of K-mount lenses; one is an APS-C (18-250 Sigma which has been my "one lens" with my K5IIs on vacations) but the rest of them (which I do not use very much) are as follows:

- Pentax 50mm f2.8 FA
- Pentax 50mm f2 KA (manual focus)
- really old but smooth Vivitar 70-210 f4.5-5.6 KA (manual focus)
- Tamron 28-80 f2.8 (auto exp/focus)
- Sigma 28-105 f2.8-4 (auto exp/focus)
- Sigma 28-200 f3.5-5.6 (aufo exp/focus)

Why so many of the "28-..." variety? Cheap and allowed me to jump into an auto-focus zoom lens (with greater+ reach). Frankly, I do not use the Tamron nor Sigma 28- lenses any more as the 18-250 does it all.

If I bought a K-1, all of my lenses (except the 18-250 Sigma, of course) are full frame. So, with the not-insubstantial initial cost of the K-1, I already own a bunch of full-frame lenses. The Sigma 18-250 ends up staying on the K5IIs so it becomes a large "bridge camera" as I probably don't have a need for any other lens there. The Sigma 28-105 would probably end up as my daily "one lens" with the 50mmFA doing macro work. I'd have the 28-200 when a longer reach is required.

I should also mention I was gifted an old Spotmatic setup with a bunch of SuperTak screw-mount lenses so, again, more full-frame lenses (albeit manual).

So here's the crux of my question: I know the Sigma FF's are not the sharpest (and I may be being generous) but considering the extra size of the K-1 sensor (and resulting # of pixels), would that not offset the reduced sharpness of the lower quality lenses (lower than genuine Pentax)? I can spend $3000-4000 for a Fuji XE-2 with some lenses but wouldn't the K-1 with my existing lens perform as well?

Advice appreciated.

Thanks,
Barry

[biz-engineer]

Lesson learned from the Pentax K1, the larger the sensor the more expensive the whole system, better limit cost by careful choice of the lense(s) (using less lenses, but making better use of the sames lenses). Actually, a lot can be done with one lens only (and a camera body, of course).

[i_trax]

I had a K-1 for a while , the Tamron 28-75 2.8 my mostly used FF zoom, very happy with the results,
never heard about Tamron 28-80 f2.8
kind regards
jack

[vitc]

Since you are pretty happy with the camera itself, why not to replace the soft lenses with sharp ones? Pentax makes a lot of good APS-C glass, and it's not expensive, especially if you buy used. You'll benefit from their compact size, which matches the compact K5Ii body, more convenient zoom ranges, and possibly full weather proof setup. If I had the same choice, I'd take 16-50/2.8 + 50-135/2.8 + couple DA Limiteds. All together they would cost about as much as bare K-1 body.
Please keep in mind that K-1 is bigger and heavier than K-5, and might require extra investments, like memory cards/computer upgrade/newer software.
I have both cameras (K-1 and K-5II), and still cannot let K-5 go. I really enjoy its compact size, and take it when travelling overseas.

[D1N0]

The D FA 28-105 F3.5-5.6 is not very expensive but very excellent. You could get that lens once the shock of investment in the K-1 wears of. The FA 50mm 2.8 macro is a very sharp lens. Will do well on the K-1. If that Tamron is in fact the 28-75 F2.8 it is also a good enough lens for the K-1. The Takumars you can adapt to the K-1. Takumars are good lenses and a few of them are very good.

[BigMackCam]

So here's the crux of my question: I know the Sigma FF's are not the sharpest (and I may be being generous) but considering the extra size of the K-1 sensor (and resulting # of pixels), would that not offset the reduced sharpness of the lower quality lenses (lower than genuine Pentax)? I can spend $3000-4000 for a Fuji XE-2 with some lenses but wouldn't the K-1 with my existing lens perform as well?

Barry - the K-1 sensor's pixel density is more-or-less the same as the K-5IIs. Hence, you can expect performance at the center of the frame to be almost identical to your K-5IIs in terms of resolution and how "sharp" things look when using the same lenses. Of course, the field of view is much wider with the full-frame K-1 because of the sensor size, and that will utilise a greater area of the image circle. The border / edge performance of those lenses on full-frame will likely be worse than you're used to seeing on the K-5IIs.

Regarding your comments on pixel-peeping images... With respect, I'd say it's your lenses rather than your camera that are limiting you right now. The same lenses used on the K-1 won't give you any better IQ at the pixel level. Of those you've listed, only the Pentax FA 50mm f/2.8 and (when stopped down a little) Tamron 28-75 f/2.8 are going to give you really sharp images. Rather than changing cameras, you might consider investing in some better glass; I think you'd be amazed by the improvement. A K-5IIs with a really good lens will considerably outperform a K-1 and mediocre lens any day of the week.

I'm not trying to discourage you from buying the K-1; but only buy it if you want or need a full-frame sensor. It's quite different from shooting APS-C, and has both advantages and disadvantages depending on the application.

[Kiwipixter]

Sell your Tamron and Sigma 28-105 to fund for the D FA 28-105 DC WR, you'll not regret it. For not much $$$ you'll get all the bells and whistles of a modern lens, WR, DC motor, HD coatings etc.... And it is very sharp, even sharper than my DA 70mm. Imagine having a Ferrari, would you run it on low octane gas and 20-year old tyres?

[clickclick]

Try to figure out what your favorite/most frequent focal lengths are and how that would translate over to the K1 e.g. do you shoot wide or telephoto more? Something in between? Also, what about low light? I love my K1, but still use my K3II more than I expected I would when I bought the K1. If I'm looking at the telephoto side, I go back to my K3II with the D FA 150-450. When I'm shooting roughly under 100mm, I am going with the K1. If it's a low light scenario, it's the K1. If I'm on the go, I have to think hard about size and weight, and the K3II and some smaller/lighter lenses is very appealing - walking the dog the other day I wanted a camera - took the K3II with the 16-50 mounted and the 55-300 stuffed into a large pocket on my shorts.. Different tools for different jobs - perhaps think of the K1 as an expansion of what's in your kit and not a replacement.

[TER-OR]

Since you are pretty happy with the camera itself, why not to replace the soft lenses with sharp ones? Pentax makes a lot of good APS-C glass, and it's not expensive, especially if you buy used.

This.

There's nothing your K5II can't do. Look for a DA40mm pancake. It's inexpensive and very sharp. I use my DA21 more often, it's great in close quarters but the 40 is less costly. Plus, pancakes. The DA35 f2.4 is inexpensive and quality optics. I don't have one, it overlaps too many other lenses in my lineup. I can't recommend the DA21mm enough, it's really fun on ASPC, has loads of contrast, "true" normal view - looks like you're looking with your eyes. Yes, I know it's not mathematically "normal view" but it certainly delivers that perspective on the monitor. Plus, it's quite sharp and focuses closely.

Those manual 50s are very sharp, but you have to do the work.

If all your lenses are lackluster, you may have some fine focus adjustment to do - though that's tricky with zooms.

[VoiceOfReason]

The K1 will give you better images, but you're being limited by your lenses right now, not your camera. Sell off your Sigma 28-105 and 28-200, lenses. Double check your Tamron, and if ti is the 28-75 f/2.8 then keep it. Get the Tamron 70-200 f/2.8 to match the other if it is the 28-75 f/2.8. Keep the 50 f/2.8 macro, and sell the 50 f/2 and 70-210. Use that money to buy a good Tamron or Kenko FF compatible 1.4 tc, then enjoy. If you're really wanting a walk around lens either get the Pentax DFA 28-105 or find a Tamron 24-135.

Another option is to sell those same lenses, check the used market here, and snag the Pentax DA* 16-50 f/2.8, DA* 60-250 f/4, and DFA 150-450 which will cover all you need.

[mcgregni]

It doesn't sound to me as though you need a new camera. Getting a K1 is a waste of money for pairing with the glass you have I feel. With good lenses plus good techniques, the K5IIs is capable of images as 'sharp' as anyone could ever want.

I agree with the suggestion to sell lenses and get the D FA28-105mm ....plenty of us, (me included, on a K7!) use it on APS-C and it is excellent and versatile, just as good as a prime in many configurations. The advantage is that you are ready for a K1 in future should you decide you need the extras that it provides. I'd also think hard about more specialised lenses to suit your preferred subjects ....e.g. a 70, 77, 85 for portraits, 100mm macro (perhaps for portraits also) or a wide angle like a 14 or 15mm.

The fact that you have been using a superzoom mostly suggests that you are not a 'Full Frame photographer', or at least not someone who needs the larger format or the expense of it. Using more specialised lenses that fit more distinct subject types, and exploring more that way, is going to end up with you getting better images, more so than a new camera. Get lenses that are FF compatible and the jump to a K1 or its successors in future will be easier.

[eminker]

Barry - the K-1 sensor's pixel density is more-or-less the same as the K-5IIs. Hence, you can expect performance at the center of the frame to be almost identical to your K-5IIs in terms of resolution and how "sharp" things look when using the same lenses. Of course, the field of view is much wider with the full-frame K-1 because of the sensor size, and that will utilise a greater area of the image circle. The border / edge performance of those lenses on full-frame will likely be worse than you're used to seeing on the K-5IIs.

Regarding your comments on pixel-peeping images... With respect, I'd say it's your lenses rather than your camera that are limiting you right now. The same lenses used on the K-1 won't give you any better IQ at the pixel level. Of those you've listed, only the Pentax FA 50mm f/2.8 and (when stopped down a little) Tamron 28-75 f/2.8 are going to give you really sharp images. Rather than changing cameras, you might consider investing in some better glass; I think you'd be amazed by the improvement. A K-5IIs with a really good lens will considerably outperform a K-1 and mediocre lens any day of the week.

I'm not trying to discourage you from buying the K-1; but only buy it if you want or need a full-frame sensor. It's quite different from shooting APS-C, and has both advantages and disadvantages depending on the application.

Definitely agree with BigMackCam and Ter-Or on the advice to whether to pull the trigger on a new K-1.
I've been shooting with a K-5 and K-5iis (bought a second used body so that I don't need to change lens as much) and everything boils down to the glass. if there's a particular reason/application where a FF sensor would be a help or a necessity, definitely pull the trigger. For me, its photographing historical houses, travel and lots of landscapes. The K-5iis does exactly what I need it to do even though I can definitely make a good case the FF K-1 would be great on landscapes. I'd rather continue to get my technique and experience in before moving to FF. Novice technique + marginal glass + FF still equals not so great photos. Just my $0.02 .......

[jatrax]

As most everyone else has already said, it is not the camera but your glass. Outside of the FA 50mm f/2.8 you have rather slow consumer zooms. Changing to a K-1 and using that glass is NOT going to improve anything. So if you want to move to the K-1, which is an amazing camera, you should also budget for the DFA 28-105 or the DFA 24-70.

Maybe a good idea would be to get the DFA 28-105 now, and see what it does on the K-5IIs. You will then have a very good modern zoom that you can use now and will be FF capable if/when you make that move.

[shardulm]

Sell all your lenses or the one you like most or find most versatile and get into the DA* line up. Once you taste the IQ you will never go back to non-star * optics. I know that is equally expensive but for the price of K-1 you may be able to fit in a DA*16-50, DA* 50-135 (a beauty) and a DA-L 55-300 to cover all the FLs and get superb IQ each time every time.
Don't buy K-1 and expect the old lenses to shine (well they will to an extent) but good glass is good glass and bad glass is bad glass at the end of the day. Like one other poster mentioned K-1 has the same pixel density as the K-5iis. Besides all your FLs will get a 1.5 times boost from FOV perspective. If you are seeing a future upgrade inevitable then venture into primes, an FA77 or an FA31 or a DA*55 which will be a long term investment. Begin investing in good glass first and wait up for the FF upgrade until you are ready. K-5iis is no slouch by any means. A friend of mine (a huge Canon 5D series fan) always gets uncomfortable (well jealous pretty much) when he sees the images from my K-5iis and DA* 50-135 combination (and he refuses to see images from K-1 for the obvious reason or goes silent when he sees some). K-5iis squeezes out every once of sharpness from the lens. But if the glass isn't sharp... then.. well you hit the glass ceiling (pun that is).
On a suggestive note: There is only one worthy keeping from your list and that is the Pentax 50mm f2.8 FA. I assume its a Macro. because Pentax does not have an FA50@2.8 that isn't a macro.

Its like.. what location is to real estate, glass is to IQ.

[Adam]

Sell your Tamron and Sigma 28-105 to fund for the D FA 28-105 DC WR, you'll not regret it. For not much $$$ you'll get all the bells and whistles of a modern lens, WR, DC motor, HD coatings etc.... And it is very sharp, even sharper than my DA 70mm. Imagine having a Ferrari, would you run it on low octane gas and 20-year old tyres?

This. It definitely doesn't make sense to use sub-par lenses on the K-1 and the 28-105mm is one of the best values you'll find among modern lenses. Your FA 50mm and Takumar primes should be fine to use; I'd skip over the other lenses and just use the D FA 28-105mm until you're able to update your collection of primes and longer lenses.