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发表于 2008-6-28 05:27
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Pentax K20D
If you’re thinking you’re going to get a small upgrade to its predecessor (Pentax K10D) then you’re definitely wrong!
The body looks almost the same but there are a few differences and let me explain them to you.
First there is a PC sync port that has an overload circuit incase you have a surge. Second there is a larger lever to access the weather sealed card door. The most obvious standout is the larger and much higher resolution screen… 2.7” 630,000 pixels (including sub pixels)! Pentax calls this 230,000 dots (each dot has Red Green and Blue pixels). Besides that the body is exactly the same and that is great because your BG2 grip will work just fine from your K10D.
Things that didn’t change… I’m going to get this out of the way really early and tell everyone that the AF sensor, AF drive motor, mirror assembly and associated parts are all the same besides a dampened mirror bay. This is really going to make a lot of users unhappy because a lot of people have frustrations with the AF system of the Pentax K10D including myself. I was explained the reason and here it is so it’s out there:
Pentax engineers had two choices when updating the K10D in order to stay profitable. One was to advance the AF system and mechanisms to bring it up and beyond the current cameras in the class. Second was to advance the imaging and allow it to be the most advanced photographic tool available. Pentax went with upgrading the imaging guts because having a better AF system and the older imaging end wouldn’t sell well enough. Every camera on the block has a newer AF system, but the imaging system isn’t anything that stellar till you jump to the full frame models. In my honest opinion I would also go with imaging vs. AF system any day, but that’s because in my mind the quality of the image matters more than how well the camera can focus/track/predict. I feel that this is the only area in which this camera fails to be the most astounding camera of 2008. Many camera reviewers will look at this and will probably point this out enough to bring the value of the camera down, but Pentax has a few tricks up their sleeves and I will explain this all later. I got this straight from the Pentax Japan engineers that were there training the US sales reps on the K20D.
So we still have 3FPS and we will still have the same low-light AF ability coupled with the same 11 AF points with 9 of those being selectable.
What has changed in the camera? Way too much for me to ever remember hence why I wrote this article ahead of time so I could make sure I have all the bases covered when the camera is announced.
The sensor… this sensor is most likely the most technologically advanced sensor on the market period. This is the very first high resolution sensor and actually breaks the quality of many lenses on the market. 14.7 effective megapixels… that sounds almost ludicrous! Many of you are probably thinking well small pixels right? WRONG! The pixels are actually the same size as the pixels on the Sony 12MP sensor that is in the Sony A700 and the Nikon D300! Now you’re all thinking that I’m nuts because there is no way Pentax has this sensor technology because nobody else has it. Sorry guys they do have this technology because they patented it and Samsung built it. We now have a high resolving sensor with high sensitivity! Somewhere a rep told me that each pixel has a base ISO1600 sensitivity, but this could be different or an interpretation. It’s basically magic like Ken Rockwell always says when he doesn’t want to understand how something works. Not only does this sensor have great sensitivity per pixel, but is self repairing! With a couple of button presses you can fix dead pixels on your sensor while you wait. Huh? You know those dead pixels that happen from time to time. Basically you’d send your camera in to be repaired and they’d send it back with that dead pixel mapped out of the equation. The K20D can do this for you in camera folks! So let’s sum this up… a 14.7MP, high resolution sensor, low noise, and self healing!
Since we are on the topic on the sensor lets talk about sensor dust. Pentax has there sonic method of dust removal, but have implemented a new advance in that. Think of it as taking a printed image and flipping it upside-down and on the white backing of the image the specks of dust are visible. Yes, it will find the dust and show it to you! Marvelous! This makes cleaning a breeze because you know where to look and if you have to look plus when you have that image on the computer you can find the areas to clone out that much easier.
The next step from the sensor is the capture ability. Well, it shoots 14 bit RAW images (the source material shows 12 bit and the documentation I was shown says 14 bit RAW so I will leave this with a biq question, but feel 12 bit is correct for now) that are just stunning to say the least. The sensor has a true color ability that gives you vivid images and plenty of dynamic range. Still shoots 3 frames per second… but it can also shoot faster than the Canon 1DMKIII in a special mode. How fast? Let’s just say 20 frames per second! It’s only at 1.6MP, but hey it’s a number and numbers sell right? I thought it was a gimmick at first, but then I started to think about certain applications where this may be a pretty neat feature. During a model shoot, switch to this mode and fire off a few seconds of this feature while you’re model is moving or interacting. Build a massive image in photoshop showing the movement row after row! I think it’s a dramatic effect and could be used for many different applications, including sports and wildlife.
Now we’ve moved to the actual image processing. If you hit the function button (Fn), then hit OK you will access the picture style settings. You start off in vivid and there are a lot of options here. Of course you have your color saturation, contrast, tone, and sharpness level, but there is so much more. The tone is new and something Canon users have some familiarity with. The sharpness mode has a new feature and it’s called the fine sharpness setting. Think of it as the edge sharpening tool because it can really punch up the level of edge sharpening really really quick. Next mode is natural, then portrait, then blah blah, and now we go to monochromatic. I skip the rest because they aren’t as amazing as the monochromatic mode! This mode differs because color settings have been changed with filters! Remember how we shot B&W film and used colored filters to enhance or change the outcome, well it can be done in camera! There were these filters in no specific order: Red, Green, Blue, Yellow, Sepia, Orange and oh… did I mention one of those filters is an infrared filter! Yes, you’ve heard it from me folks you can shoot infrared style images right in the camera without a special filter and without the super long exposures! From what I was able to play with I was able to use all these setting not only in JPEG but RAW as well, but this was not a fully functioning firmware version so we shall have to wait for the final firmware to make a final judgment.
Now that we’ve taken some images we can look at them in our new fancy 2.7” screen! Sure it’s not 3” but we have the ability to do something that no other screen can. What is it? Oh this screen can be temperature calibrated! Accurate reviewing is now possible! So now that the screen is temperature balanced and you’ve begun to review your images you think to yourself how can this get any better and there is a way. This screen will allow you to view the scene live… with live view. To turn on the live view you press the DOF lever over and it starts up when the mirror locks in the upward position and viola, you are viewing what the sensor is seeing. The firmware didn’t allow for AF to be activated but while playing with the system for a while I like it. The frame rate was equal to that of the Canon 40D from what I could tell. While in Live View you can add grid lines and even show representations of you’re AF points, which is a great touch. While in AF selection mode you can move to any available AF point and see it on the screen, which again is another great plus. The rep said all I had to do was press the AF button on the back of the camera to autofocus , but it wasn’t working, but when I hit the shutter button half way the mirror would quickly fly back, focus using the point you selected, meter, then swing back up and go right back into the live view mode. Not sure if this means no contrast control AF, but it’s tough to tell. I kept playing with this and I noticed that if you hit the shutter all the way down instead of half-way the camera would also take the picture then swing the mirror back up and go into live-view once again. I like this setup already and if they add contrast detect AF it’ll be a huge plus and if they don’t then Olympus still has the best live-view on the market. Oh, so far we could zoom in while viewing 4X and 8X, which is a nice touch, and it handled very well.
Other neat features of the camera that I just want to briefly discuss:
-Changeable file folders and file names. Basically instead of Pentax100 you can assign any name to the folder and also instead of _IMGP0001 you could have _COOL0001 or _MINE0001.
-Trap focus function. From what I was able to determine this disable Pentax’s double check in focus and as soon as focus is confirmed it will fire away. I played with this is AFS-C and it fired away much much faster than the K10D.
-White Balance. Apparently this mode has added even more customizability for greater range of white balance control.
-Scrolling menu items. Instead of Remvng Vowls to make the text fit, once you move onto a setting that is too long it has a scrolling marquee effect. Nice touch guys!
-Larger text for the vision impaired. You can change the size of text to either standard or large in case you have a hard time reading what’s on the screen.
-200% dynamic range mode. Not perfectly sure on all this, but from what I was able to play with it basically increases the sensitivity and gives you a dynamic range I’ve never encountered… almost HDR in effect.
-Fixing front/back focus issues. Right in the custom function you can access this bad boy to fix any lens and store up to 20 profiles so all your lenses can be perfect!
-Shake reduction. Well we were told that there was vast improvements and we were not able to test them with any real trials, but the word is 4 stops is easy to obtain and they will push that fact, but the specs show 2.5-4 stop SR.
-Built in programmable self timer. Yes you can now do your time lapse shooting right in the camera. Set you number of shots, sequence and time. Have fun with this one and no need to buy and extra remote ala D3!
-The mirror slap was much less noticeable. From what I was able to observe the camera was quieter and functioned much quicker.
There is probably more, but my brain can only store so much information from playing with a camera for two hours. So to sum this up, the bad will be the AF is the same system as the K10D, with a few changes to algorithms. The good… well if you look at everything above it’s all gotten better and they have addressed many of the minuses from users and reviewers except the AF. The “bomb” feature… IQ! The image quality is stunning and it will put a lot of higher end cameras to shame especially if you have good glass. After peeping dozens of images from the K20D in beta firmware fashion it’s hard to deny the stunning quality of these images and it will blow many reviewers and photographers away. Ben Kanarek, Canon’s fashion photographer of the year 2006, has even exclaimed that the image quality is rivaling that of Hasselblads, which is **ery bold statement, but with a lot of images backing his statement it’s hard to deny.
The new lenses, DA* 200mm 2.8 & 300mm 4, DA 35mm 2.8 macro limited, DA 18-55mm II & 55-300mm, will be available by the release of the new bodies and will be competitively priced. The DA* 60-250mm 4 has been pushed back for a fun reason. Apparently Hoya has developed something extra special and this lens will be the first to include it, but only time will tell if this statement is true. That’s all I have and you’re more than welcome to ask questions and I’ll try and answer them from a users stand point.
I’m excited about the camera and only have one grief after using it and viewing the gorgeous pictures it can capture and that is the AF system was not improved to what I would like it to be. Did they improve it? Yes, a little, but there is so much more in this camera than the K10D and it’s going to be another explosive hit.
Estimated US price is $1299 body only and $1399 with the new DA 18-55 II. All previous K10D accessories will work on the K20D including grip, focusing screens, etc.
*DISCLAIMER* All of these statements are my own and it stems from a prototype camera that lacked full functionality and a finalized firmware. Things can change drastically when the final product hits the market. If for any reason you have handled a camera of newer firmware and setting have changed please inform me so I can make appropriate changes. Under no circumstance may anyone reproduce any of this, but can link this physical thread as much as you like. So you better have my permission before you try and copy and past this onto your own website.*END DISCLAIMER*
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-Chris |
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