Pentax K20D Report—Part I: Focus

By Carl Weese

Spring has arrived, my favorite time of the year, especially for color photography. This caused me to take a deep breath last week and decide to buy a K20D to expand my Pentax equipment set. I’ve recently had some print sales, big enlargements from K10D captures with the superb Pentax prime DA lenses, and I really wanted to see what a 46% increase in pixel count would do for such prints. The camera arrived Monday. We’ve had terrible weather all week—clear bright sunlight, blue skies, puffy white clouds—my least favorite shooting conditions. The good news is, this forced me to spend nearly three days doing purely objective technical tests before finally charging out into the field to try some real world pictures yesterday, despite the continuing pretty postcard weather.

In external appearance, the new camera could be the K10D 1.1. It looks so similar that the most obvious change is the welcome addition of a standard PC flash sync socket. But in terms of performance, the new camera is a lot more like version 5.0. There are so many improvements I’ll need several postings to list them, while so far I have not found a single “deprovement”—no changes I wish the engineers hadn’t made.

My first focus is, well, focus. Specifically AF performance. I hesitated several weeks before buying a K20D because the manufacturer’s literature states that the camera retains the K10D AF system. Since I found AF to be the K10D’s biggest weakness, this gave me pause. I’m happy to report that the AF is not the same, and all to the better. First, AF action with the lenses I’ve tried is faster, crisper. (Pentax may still say the AF is the same: I’m simply reporting my impression based on tens of thousands of exposures with the K10D and now 519 with a K20D.) AF accuracy is also improved. The K10D focus points were too much like broad patches for my preference: aim at a flower in front of a wall, and it would focus on the wall. Hold your hand out in front of the camera and point the AF patch at it and the focus will be perfect, but hold up just one finger and the focus will snap to the backgrounnd. Not a matter of back-focus, it was just blind to narrow objects that I would expect AF to recognize. The K20D consistently focuses on targets the K10D would miss.

Gate, Torrington, Connecticut

I shot three frames of this subject, de-focusing the lens between shots, and the AF, in single shot selective center spot, snapped onto the iron gate each time. The older camera would have invariably focused on the brick wall in back, requiring manual over-ride.

AF accuracy is further improved by a brilliant new feature: user-adjustable AF focus point correction. With the camera firmly mounted on a tripod, aimed at a focusing target (you can easily find one for download on the web) make several exposures, download to a computer and view at 100% magnification. If the focus is in front or behind the intended point, go into the camera’s menus and change the custom setting, then test again. Of five modern Pentax AF lenses I have handy, one required a hefty correction of +6 (out of a possible ten), one needed +2, another benefits from a tweak of +1, and two others are dead on the money as is. The camera recognizes the lens as you mount it and applies your custom correction factor. My understanding is that the camera recognizes the lens by type, not individual serial number so if, as in my case, the factor of +6 is set for my 21mm DA Limited, the same factor would be applied if I borrowed someone else’s 21, which would likely introduce an error. You can also set a factor for all lenses which in effect means a correction for the camera itself. Of course this feature is ripe for abuse. Careless or mistaken use of AF correction could easily ruin the performance of excellent equipment, so use with extreme caution. But oh boy, do I love this feature!

Speaking of quick and crisp, the new camera is rated for the same 3 fps sequence shooting speed as its predecessor, but the action feels faster and “tighter.” I almost never shoot sequences but I certainly want the shortest possible lag time from button push to shutter actuation. I don’t have equipment to measure this, but the new camera seems to release closer to NOW than the old one. It also helps when making a grab shot if the AF is fast and certain.

Heineken, Winsted, Connecticut

This is an example. I turned a corner, the delivery truck roared by, and I shot two frames, barely getting the camera to my eye. Auto focus, auto (program) exposure, just a little tweaking of the RAW capture in ACR.

Next time, changes brought about by the completely new, 14.6 MP CMOS sensor.

_______________________

Carl

Carl's website 
Working Pictures
WPII

Comments

[Adam Zolkover]

Nice impressions. I just upgraded from a K10D to a K20D myself, and am having much the same experience. AF was nigh on impossible in low light conditions with my K10D, but the K20D does an admirable job with a little bit of hunting, but not too much. Similarly, AF accuracy seems much better. I've had back focusing problems with my K10D that have gotten progressively worse over the past six months or so. But the K20D is spot on, no adjustments necessary, with all my AF lenses. I've taken fewer than 100 exposures with the K20D so far, but if it continues along these same lines, I suspect I will be much happier with the new camera.

[Ctein]

Dear Carl,

Have you got any before/after examples showing how much the image sharpness was improved by applying the custom focus corrections? It'd be nice to see 100% sections from the +6 and +2 lenses.

Geekily yours,

Ctein

[Charlie H]

Carl, I enjoyed looking at your work from Lenni, PA; let's see some more. Also, as a fellow Pentax user I am looking forward to reading your impressions of the 20D. Glad to see the AF has improved. ch

[Carl Weese]

Ctein, in fact I burned my test files to DVD, so I can dig out the tests that led to my correction settings. Soon but not immediately...

Charlie, there's lots more from the Lenni project and I do want to post. Maybe I'll get another installment up tomorrow.

[Bill Mitchell]

I bought a K20D (with their 18-250mm lens) the first day it was available from B&H, used it a week, and returned it after spending a whole frustrating Saturday trying to figure out unsuccesfully how to use my wonderful, exquitely sharp and contrasty SMCP lenses from the '80s.
I also had very bad news from my tax accountant (I was waterboarded by the IRS), so I now have a new Canon XSi which is a pound lighter and $1000 less expensive (with the kit lens)than the K20D.
Focusing the Canon is, by comparison, an absolute joy, but except for the weight and cost, IMO the Pentax is a much, much better camera.

[Geoff Wittig]

Hey, Mr. Weese. We (briefly!) met about six years ago in rural West Virginia. I was photographing Germany Valley on a hazy autumn afternoon with my (then) 10 year old son, from a road-side overlook. I was actually using a Pentax 35 mm film system at the time. You pulled into the parking area, and promptly hauled out what I recall was a wide format view camera. I finished shooting and packed up after I realized my son was tormenting you with questions about your funny looking camera as you were setting up a shot.

Small world!
Geoff.

[Matthew Miller]

Bill Mitchell -- for future reference, go into the Custom Settings and change Using Aperture Ring to "permitted". Then, use the green button to take meter readings.

[XebastYan]

As one of the two Admins of the PENTAX(SAMSUNG)DSLR Users Group over there @ flickr, the (not a real) problem by Bill Mitchell is one of the most posted probs and questions regarding Pentax DSLR's. Matthew Miller has told the correct way to solve it.
---------------------------------------------
Mr. Weese thanx for Part One, we are ready for Part Two. Nice work, nice words. thanx for testing and letting us know.
groove on
Xeb.

[Emm Jay]

Speaking of focus talented landscape photographer Darwin Wiggett just recently tested the AF on some top shelf Canon dslr's as well a Nikon D200. Manual focus won out over AF every time. Check out the results.
http://www.naturephotographers.net/articles0408/dw0408-1.html

[John Hanover]

Dear Carl,

As a K10d K20d owner I would fully concur with your findings regarding autofocus speed and accuracy between the two cameras. I have made similar posts recently to alert other users about this difference. I am secretly hoping that this is merely a firmware issue and that the emergence of the k20d will inspire Pentax to beef up the K10d firmware to allow similar performance. The K20d firmware is also superior in JPEG rendering and has many new customized features. My favorite is the ability to constantly display ISO in the viewfinder and LCD replacing the number of remaining shots. You get the remaining shot information upon power-on, power-off anyway.

Thanks for your always informative reports

[JohnBrewton]

Carl, thanks for the report. I've been sorely tempted to pull the trigger on buying one of these, but I'll wait for the rest of your experiences AND the introduction of the new 300 f4.

[Thiago Silva]

Hi,

I remember reading somewhere that the K20D gave the user the option to disable the "double check" characteristic of Pentax, which would speed up focusing time. But then I never seen it mentioned again. Do you recall seeing anything about it in the manual?

Cheers,

[Miserere]

Hi Carl,

As a happy K10D user, I'm looking forward to reading your views (those of an actual photographer, vs the tech geeks that test cameras at other sites) on the K20D. There are a few features I would love to have that the K10D lacks (like the customisable focus settings), but I cannot justify the price just for that.

However, I *DO* want the K20D to do well (as a camera and in sales numbers) because I'm looking forward to upgrading to the K30D in 18-24 months :-) Guess I should start saving money now.

My tech geek comment notwithstanding, I also second Ctein's request for comparison shots showing the improvement with the custom focus system.

[Erl Houston]

Carl,
Thanks for the first installment. I, too, eagerly await your future reviews. As a current user of the K10D, I am debating whether to upgrade. I am pleasantly surprised at your belief that the K20D focuses faster and more accurately.
Many thanks,

[Russ]

Your impressions regarding the improvements of the K20D over the K10D are the same as mine. For some reason, Pentax lists the K20D as an "evolutionary" upgrade to the K10D, but in almost all areas that count (AF, resolution, noise, high ISO capability, user tweaks, etc), the K20D is a major upgrade to me. I'm very happy I switched.

As for Bill Mitchell's problem finding out how to use manual lenses on his K20D, it's too bad that Pentax doesn't make that "enable aperture ring" (or whatever it's called) the default instead of making new users search through the manual to find the solution. As another poster pointed out, this is one of the most-asked questions of any new Pentax dSLR owner. Seeing as how Pentax (rightly) touts the ability to use any Pentax lens made on their dSLRs, you'd think this ability would be the default performance, not buried in a menu. I'm not even sure why anyone would turn off that capability.

Looking forward to reading the rest of your review.

[Meg Sixx]

i only just decided today i wanted to upgrade from my Nikon D40 to the Pentax K20D. your post has not only helped to inform me of what an excellent idea that is, but it has made me yearn.

[Mal Daughtree]

I've been an avid and staunch Pentax ME Super advocate, trying (in vain) to remain focused. But, as film, processing and digitising costs skyrocket, I have to change. Change is a good thing and my *NEW* K20D is the first digital camera not in a phone. The main selling point for me was that I could still use my lovely Pentax SMC lenses I've been using for decades, since 1981. Smooth, sharp and made of metal. HEHE !
The K20D is finally a worth successor to my faithful and still much loved ME Super. Like any antique the ME is one to preserve and pamper, but, the K20D WOW ! what a camera. I did take a little hunting to find the aperture ring permit setting, about an hour, but there was necessary required reading in between. It handles well and feels solid and smooth in the hand. Put a nice SMC 35 to 70 mm on it and from the the first shot, wham !! crisp images and lovely contrasts I am used to using film. Where to from here ?? I hope as long as an association with the K20D as the ME Super !

[Cateto]

Thanks a lot for posting, Carl!

Last year, after I purchased my K10D, I found your previous series of articles on it. All of them are bookmarked still today, and I learned a lot both on photography and on the K10D by reading these articles, written by someone who is not worried about numbers and pointless pixel peeping, but rather by actual photographs and how to take them.

[Sune]

Hi Carl,
you wrote :
"We’ve had terrible weather all week—clear bright sunlight, blue skies, puffy white clouds—my least favorite shooting conditions"

What sort of lighting conditions do you prefer ? I thought overcast weather sometimes caused dull gray colour pictures.

Always a pleasure reading your blog, looking forward to the upcoming parts.

kind regards

Sune/Jonson PL

[patti]

What a great source of info for my new Pentax K20D (which I have had for about 5 hours and haven't got a clue what I am doing. Bought it because 'it said' ALL my old lens' would work, and if it was not for Geoff, I would never have figured it out. Now it works, but the flash is WAY over exposed, so working on figuring it out. 30 years ago I was a freelance photojournalist, until my car was broken into and lost everything. First time since then I have ventured back into the 'real' world of photography, and will be reading a lot in the coming months. Thanks for all the great tidbits.
Happy clicking
Patti in Redmond, WA

[Graeme Catty]

Advice required. I intend to purchase either a K20D or a K200D shortly. As a new entrant to the digital SLR field, my question is: Should I buy the more basic (simpler to use?) 200D and grow with it as my knowledge increases, or buy the more sophisticated 20D from the outset? All the camera shop staff I ask give conflicting answers.

[Joshua Schroeder]

Thanks for the comparison. This focus issue on the K10D has been driving me crazy lately, so much so that I've been contemplating selling off all my Pentax gear and going Canon. Your K20D review certainly gives me more faith in finding a reliable body to pair with my substantial lens investments.

[Hoyt Maulden, Jr.]

OK team, I give up.
Where do I acquire an adapter/aperture ring so I can use my great 70s Super Takumar Pentax lenses with my new K20D? Let me in on the secret, please..... Hoya/Pentax is not forthcoming. WTF?

[Darrell Wright]

This is one of the best articles I have found for the Pentax K20D. Everyone else and their brother on the web bash the camera. But the image quality I have seen. I downloaded a few images from other reviews where they have high ise and ran them through CaptureNX and Dfine 2.0. I must say with the iso 1600, 3200 after removing the noise it looked awesome. I was a little disappointed with some online photos where the focus was a big problem, most images appeared smeared at the edges. My guess is the people doing the tests do not know what they are doing, or they have not figured out how to use the camera settings. It is either the K20D or XSI. About the same price now.

[Dave Russell]

Graeme Catty - I bought a Fuji finepix to learn about digital. From there went to the K20 with concerns it was too much. You don't have the pic icons but I found it easy to get around. In reality it's much better once you get it set up. My point and shoot girlfriend loves it.