Pentax K-3 II Field Test Part II
Rounding out our head-to-head of the enthusiast flagship twins
By Mike Tomkins | Posted: 04/27/2016
Some months back, I kicked off my review of the Pentax K-3 II with my first field test, in which I looked at its daytime image quality, in-camera geotagging complete with compass, and gave an in-depth rundown of its clever Pixel Shift Resolution function which boosts per-pixel resolution for static scenes. (And I gave you a handy tip on how to use it for scenes with a modest amount of motion, for good measure.)
As you could probably tell from that field test, I really enjoyed shooting with the K-3 II, much as I had with its excellent (and closely-related) sibling, the original Pentax K-3. Both cameras share most of their internals, with the main difference being the lack of a built-in flash in the K-3 II, a change made to allow the addition of the built-in GPS receiver and compass. There's also a uprated image stabilization system, a boost in continuous autofocus tracking performance, and of course both the aforementioned Pixel Shift Resolution and star trail-neutralizing AstroTracer functions.
My original intention was to follow up with my second field test in short order, but several factors -- some editorial, some personal -- conspired to delay this second field test. (My sincere apologies to those of you who've been waiting!) Thankfully, your wait is finally at its end.
My AstroTracer problems continued, but it's certainly worked for others
The initial reason for the delay was due to my attempt to get to the bottom of the AstroTracer function, which as I mentioned in my initial review, I found to be rather hit-and-miss. When it did work, the results struck me as quite impressive, but unfortunately I found the function failed for me more often than not, with no real rhyme or reason that I could discern.
After several round trips of four or five hours apiece to the nearest area with really dark night skies that I could find, waiting quite some time in between for ideal viewing conditions between weather, the moon and my own availability late at night -- and having gone as far as to have the entire camera exchanged for a new unit with Ricoh's kind assistance -- I had to admit defeat.
I'm not an experienced astrophotographer, although it's a field I'd rather like to get into if I can find some like-minded friends. (Being alone in the middle of nowhere on a gravel road with a half-hour drive to the nearest phone signal and surrounded by goodness knows what wildlife was, for a city kid like me, a rather unnerving experience. Yet despite my concern, being able to see the Milky Way with my naked eye for the first time was simply unbelievable.)
I tried literally everything I could think of, ensuring that the camera was calibrated per Ricoh's own instructions, and at a significant distance away from any metallic objects including my car. I tried calibrating with and without lenses attached to the camera, and triple-checked that my tripod and head contained nothing that could be magnetically disruptive. I tried a selection of different prime and zoom lenses from the very wide to the moderate telephoto and everything in between, and with widely-varied shutter speeds. And I tried shooting in all sorts of directions, just in case this was the issue.
Nothing I did could get reliable results, however, and the few shots I did manage to get where star trails were frozen were pretty much all at home through broken, light-polluted skies -- nothing I'd want to share here as representative. So instead, I suggest taking a look at what others have managed. PentaxForums has a 90-second exposure which is quite impressive, and PCMag also managed to get reasonable results.
Perhaps the most inspirational examples of AstroTracer in action that I could find, though, were shot with the earlier Pentax K-5 and its optional GPS accessory, which is essentially built into the higher-res, more capable K-3 II. French photographer Stephane Poirier has some truly spectacular images shot with that combination on his website, and I thoroughly recommend looking at these as an example of what's possible if you've better luck (and knowledge of astrophotography) than I.
I'm just sorry I couldn't manage something similar myself, much as I'd have loved to. Perhaps at some point I'll get to the bottom of things, and be able to update this with my own examples. I certainly didn't want to delay concluding my review any longer than I've already done, however.
I had more success testing continuous AF tracking
Moving on to other topics, I found much more success testing the K-3 II's autofocus system. Compared to the earlier K-3, Pentax noted at launch that the K-3 II's autofocus algorithms had been improved, specifically for the case of a subject moving directly towards or away from the camera. As it happened, this was basically what I'd tested in my review of the earlier Pentax K-3, and so I replicated that test with the very same lenses and the newer body at the same go-kart track in Pigeon Forge, Tennessee.
When reviewing the K-3, I'd chosen this location because it had the fastest karts I'm aware of in my area, and offered a nice shooting location within feet of the end of a lengthy straightaway, giving the karts plenty of opportunity to get up to their top speed. (Officially, that's said to be somewhere around 40mph, although having timed the karts and checked the length of the straightaway, I think something like 25mph would be closer to the truth.) And the nice thing is that since everyone's racing, the karts are run pretty consistently at or near their top speed down that section of track.
I didn't have a lens with an SDM motor on hand, so instead used my PENTAX smc DA 18-135mm f/3.5-5.6 ED AL [IF] DC WR lens -- which uses a swift, near-silent DC focusing motor -- to represent a lens with built-in AF motor, while my PENTAX smc DA 50-200mm f/4-5.6 ED WR lens represented the screw-drive side of the equation. Both are consumer-grade optics, so you'll want to bear that in mind when browsing image samples: You can't expect pro-grade control over aberrations and the like from lenses in the US$200-500 price range, but in terms of AF performance the results were pretty good.
Just as I found in my K-3 review, when set to continuous high mode with continuous autofocus in focus priority release mode, the Pentax K-3 II stayed pretty much rock-steady at a burst capture rate of five frames per second, just very rarely managing four our six frames in a given second. And this was the case regardless of whether I shot with a lens using the body's screw-drive autofocus motor, or one with its own internal focusing motor. And if I switched to a new subject mid-burst, the camera quickly and accurately racked to the new focus distance, locking focus correctly before grabbing the next frame without skipping a beat.
And again, just as in my K-3 review, I'd say that better than 90% of my Pentax K-3 II shots at the go-kart track were either sharply focused in the right place, or vey close to it, with the overwhelming majority being spot on. For the remainder, any lack of sharpness seemed to be more down to motion blur than to potential focus issues -- unfortunately, in prepping for the shoot I forgot to switch the program line to sports for faster shutter speeds. Mea culpa!
Having grabbed close to 700 frames of on-track action with the K-3 II, I'd say its autofocus tracking performance is certainly (and not surprisingly) the equal of that in the K-3. Is it better, though? Well, that's a bit tricky to say without being able to do a side-by-side test of both cameras, and preferably with an even faster-moving subject. Sadly, I didn't have access to an original K-3 body during my review, so I couldn't make that side-by-side comparison.
Subjectively, I'd say that the K-3 II seemed to be perhaps a little better than I remember the K-3 managing, but that difference wasn't enough that I was completely sure it wasn't just the placebo effect. Certainly, it wasn't sufficiently faster that I'd pick one camera over the other. And honestly, I wouldn't be surprised if the K-3 has quietly inherited the same updated algorithms anyway, if only so Ricoh could avoid having to manage testing and updating two forks of the same firmware.
The K-3's version 1.02 firmware update from February 2014 promised "optimized performance of continuous shooting when setting AF.C mode". It's quite possible that's the same change which was alluded to in the K-3 II announcement, and the comparison was being made to the K-3's performance at launch. If so, then the updated firmware was already on my K-3 when I did my last kart racing shootout, and so the two cameras would have been expected to have near-identical performance, just as they did in my real-world test.
Intermission: The Pentax K-3 II can (within limits) make your ND filter redundant
Having wrapped my autofocus testing for the day, I decided to shift to nearby Gatlinburg, Tennessee, a colorful -- if somewhat kitschy -- nearby tourist town that struck me as offering some good shooting opportunities during and after sunset, so I could stretch the K-3 II's high-sensitivity legs a little. Here, I wasn't expecting to see anything noticeably different to the already-great performance turned in by the original K-3, since both cameras share basically the exact same imaging pipeline, but I know our readers want to see some real-world testing nonetheless, and was happy to oblige.
I had a little time to kill before sunset, though, and so on the drive up from Pigeon Forge, decided to stop and get down to the river for a little while. I found a pretty attractive spot a short walk from a car park, and brought camera, lenses and tripod along with me. Clambering out onto a large boulder in the river, I switched to my PENTAX smc DA 10-17mm f/3.5-4.5 ED (IF) Fish-Eye lens -- an optic which I really want to start using more often -- and set the camera up at a low angle on the tripod, yielding a nice composition of some gentle rapids in the river.
I really wanted to blur the flowing water out in the foreground with a slow shutter speed, but even at base sensitivity and stopped down a fair way, I couldn't get a slow enough shutter speed for the look I was after. I didn't have a neutral-density filter on hand, and nor does the 10-17mm lens have filter threads to accept one anyway. And I didn't want to soften the image by stopping down much further, nor was I keen to lose highlight detail by overexposing the image and then dialing the exposure back in post-processing.
But one of the features of the Pentax K-3 series cameras offered a nice solution, and one that works well so long as there aren't any isolated subjects with a steady, linear motion that would leave a trail in the image. I simply set the K-3 II to multiple exposure mode using the average composite method. (That is, the camera would take the average of all values for any given pixel across all images in the multiple exposure series, rather than adding their values together.)
The result: Deliciously creamy flowing water from a 200-shot series, while the rocks and trees remained tack-sharp. Honestly, I could've gotten a very good effect even from fewer frames, but I had time to kill and figured why not let the camera run for a little while to get the smoothest effect possible. I've used this trick before, and it can also be used to reduce noise levels in the image if you want to boost shadows, or to shoot at higher ISO to get a fast shutter speed if your subject is sometimes being obscured prevening a longer shot at lower sensitivity.
It's a useful tool to remember, and really only stumbles if there is, say, a light trail from a single moving subject which would become a dotted line, due to the shutter having to recycle in between frames.
Just as expected, high ISO results were much like those of the K-3
By now, sunset was near, and it was time to move onto Gatlinburg for the last of my day's shooting. You'll find a selection of my shots across pretty much the whole sensitivity range, all shot handheld, throughout this field test, and there are more in my gallery. And to make a long story short, results were much as they were from the K-3, which is to say very good indeed.
As regards the Pentax K-3 II's improved Shake Reduction system, honestly I didn't notice much difference myself, but then I never had any complaints with that in the original K-3. I could already hand-hold impressively long exposures with that camera, and the same is true of its closely-related sibling.
Shooting in low light, focus remained swift and confident, and white balance, too, was for the most part pretty good. And noise levels even in out-of-camera JPEGs were very good at up to ISO 6400 equivalent, while ISO 12,800 was good in a pinch, but quite a bit noiser. I'd avoid straying beyond that point unless there's no other option and you're willing to live with very limited print sizes, though.
Closing thoughts
And that brings me to the end of my second and final Pentax K-3 II field test. With all said and done, would I choose the Pentax K-3 II or its flash-equipped, GPS-optional sibling, the K-3? That would be a very tough call indeed, were it not for one feature. For me, the presence of the Pixel Shift Resolution function makes that decision. If you shoot many landscapes, still lifes, or other subjects that are completely static (or very close to it), it'll probably do the same for you.
The lack of an internal flash in the K-3 II is easily dealt with by picking up an affordable external strobe, and this will prove far more capable than the internal popup strobe would have done anyway. And if you're buying an interchangeable-lens camera, chances are you've got at least a small bag with you to carry a spare lens or two, so putting a flash strobe in there as well will be no big deal.
And if, as I do, you like to have your photos geotagged as they're shot to make it easier to filter through them and find the shots you're after once you're back home, the presence of a built-in GPS rather than a chunky, somewhat pricey external GPS accessory (more so than an entry-level strobe, anyway) will also help make your decision for you. On the other side of the coin, if you don't geotag your photos and don't shoot many static subjects, there's not a lot that you'd prefer in the K-3 II over its earlier sibling, and the presence of a popup flash will likely be of more importance for you.
Either way, both of these closely-related cameras are very powerful and capable tools indeed, and if you're already a Pentaxian, ready to jump mounts from another brand, or just getting started on your DSLR journey, either the Pentax K-3 and K-3 II will serve you very well. And just as in my review of the earlier camera, I've had a whole lot of fun shooting with the Pentax K-3 II!
Follow Imaging Resource