Field Report: Canon EOS-50D
First Impressions: Camera is very similar to my “old” 40D with a slightly more textured body which seems to offer a more secure grip. Silver mode dial is a little distracting but after a day I did not notice it any more. When I received my 40D, it had 20 plus dust specks on the sensor, right out of the box from Canon. When I opened and checked the 50D for dust, I am happy to report that there was just two very faint specks, not at all bothersome, so I did not need to clean it. Excellent! Generally the camera feels more or less exactly like the 40D, which is, in my opinion, a good thing. I remembered to swap out the grid focusing-screen from my 40D before leaving and luckily it is compatible with the 50D as well. Knowing how big the images were going to be from this camera (raw CR2 files are roughly twice the size as those from the 40D) I had already purchased a few Lexar Pro UDMA 4GB 300x CF cards for it, and I'm glad I did – it really is noticeable when using fast cards on this camera. When using fast cards, the 50D's responsiveness is extremely impressive: despite the 50% greater pixel count than the 40D, it does not feel any slower... indeed if anything, it generally gives the impression of speedier performance, at least as far as playback scrolling and zooming in on images. When it comes to shooting, the fractional drop in fps certainly is not noticeable although the slightly smaller raw buffer (16 frames, instead of 17 on the 40D) is somewhat disappointing – with memory prices what they are today, I was hoping for a slight improvement and not a drop in buffer size. However I suppose I can forgive a one frame drop in the raw buffer: a 15.1 megapixel camera that can shoot at over 6fps, with a 16-shot raw buffer (or 90+ large-fine JPEG frames with a UDMA card!), priced at around $1400, really is a tremendously good deal! Playing back the first test images I took on the big 3” LCD was a revelation! I am not so much talking about the new 920,000-pixel 3” LCD screen itself (yes, it is very nice and sharp, the UI looks great, the colour balance is excellent and so on) but rather the biggest improvement I feel is that one can now accurately judge the sharpness of a raw file on playback - hallelujah! What has Canon done? Well the 50D is the first Canon xxD series camera that embeds a full-resolution JPEG preview into the raw file, so when one plays back a raw and zooms in, one is seeing true pixel-level detail, rather than a scaled-up and fuzzy looking low-resolution image like all its predecessors. Finally! Oh and about those wonderful new anti-reflection coatings on the rear LCD? While they work very well to improve visibility in bright conditions, the new screen is also the worst “nose-print” magnet I have seen in a long time! Not only that, but the nose smudges are actually fairly challenging to wipe away easily and really seem to resist casual wipes with the bottom of my shirt: you have to rub them with a fair bit of vigour to remove them. Yes folks, I have always just used the bottom of my shirt for wiping off my LCD screen and have never done any significant damage or introduced any major scratches. Even my 4 year old Canon EOS-20D (being used for infrared work the last few years) has an LCD screen that still looks fairly new with only a few minor scratches. Canon uses a fairly hard coating on their LCD screens, which resist scratches very well, and I do hope they have continued this tradition with the 50D as well. I really hate those contrast-reducing soft-plastic scratch-magnet screen protectors that some other companies use! RAW Image quality: I'm sure this is what everyone wants to know so I will make an attempt at describing it as best I can in this section. Note that these comments apply to shooting raw files, however I will add a few comments on in-camera JPEGS at the end also. In addition, at the end of this review, I will provide links to some full-resolution “zoomify” images that you can look at, just to get a better idea of image quality for yourselves. Before I go any further, let me mention that my EOS-50D came with the earliest known production firmware, version 1.01. Some currently shipping 50D bodies have 1.02 and even 1.03 installed, although as of this writing, Canon has not yet provided any downloadable firmware updates. According to several tests I have read, the newer firmware noticeably improves high ISO image quality, so I am eagerly awaiting an update! First, let me talk about low to moderate ISO images, say from 100 to 800 ISO: in this range the pixel level image quality of the 50D is very similar to the 40D, all in all a very good thing. Tremendous dynamic range, gorgeous colour, minimal noise with lots and lots of room to push, pull and stretch the contrast and colour of a raw file. When I started shooting with my 40D, there was something very hard to quantify about the raw files when compared to the 30D and 20D I shot before it – somehow I felt I simply had more room to work the files and the results were somehow just better looking. Maybe it was the 14-bit raws, versus the older 12 bit? I don't know, but happily the same versatility seems to be there with the 50D. The much higher resolution sensor, with its necessarily smaller pixels, does not seem to have lost this useful trait to any great extent. Speaking of higher resolution, is it really noticeable over the 40D? Well clearly having 50% more pixels ought to be better, right? Well yes, absolutely... with a few caveats however. When you take a “technically perfect” shot -low ISO, high enough shutter speed or tripod, sharp lens at its sweet spot, good exposure, good raw converter at optimal settings (more on that later)- then indeed the resolution improvement of the 15.1 MP sensor is quite noticeable from the 10.1 MP of the 40D. Detail is truly amazing and photos have excellent “crop-ability” if needed. So, in order to reap the resolution benefits of this new sensor, you really have to know what you are doing. Forget about cheap zooms and crappy “kit” lenses! You are going to need 'L' glass, or at the very least, a bag full of primes. Even some inexpensive primes, which perform well on all other Canon bodies, start to show their limitations on the 50D. For example, I have a cheap yet generally excellent EF 35mm f/2 lens. For the first time, I can really see that there is a quality improvement when you close it down a couple of stops from wide open – my 40D did not have enough resolution to show that clearly. My beloved EF-S 10-22mm zoom, an overall brilliant lens, is starting to look long-in-the-tooth as far as corner sharpness at some focal lengths and wider open f-stops although I did get some very sharp shots with it too. Luckily my EF-S 60mm f/2.8 Macro, EF 70-200 f/4L IS and EF 400mm f/5.6L are all up to the task and gave stunningly sharp results across the board. Canon seems to have a fairly light anti-aliasing sensor on the camera and/or the images can take a lot of small-radius sharpening without breaking down. So in a nutshell, with proper technique, yes one can really take advantage of all those megapixels, even though the 50D is not a full-frame camera. Diffraction: What about diffraction, you might ask – is it worse than the 40D and does it not limit your resolution in many cases? Well first off, for those who are unfamiliar with lens diffraction and its effects, let me give a brief explanation. When you stop a lens down, you will generally see improvements as you go from wide-open to f/5.6 or f/8, then, as you stop down further and approach f/16 and go beyond, you will likely notice that your images get softer and softer. As the lens opening gets smaller and smaller, the light rays that gets scattered by interacting with the very edges of the aperture diaphragm will start to contribute more to the overall image since the non-scattered (sharp) rays going through the middle of the opening are getting less and less. There will be an overall loss of acutance and sharp edges will start to go soft. This effect is independent of a lens' optical design and no matter how good the glass, you will always be limited in terms of resolution when your stop a lens down too far. That said, some cheap lenses might be so bad optically, that the sharpness improvements you get by stopping the lens down will overwhelm the loss of quality due to diffraction, at least to a point! On the EOS-50D, diffraction softening starts becoming noticeable when viewing images at 100% on your computer at somewhere around f/13. If you take an image from the 40D at f/16 and the same image, shot with the same lens, at f/16 on the 50D, you will see a pixel-level loss in sharpness on the 50D shot, but since the resolution of the 50D is much higher, you will still potentially see a little more detail, assuming it is (apart from diffraction) an otherwise technically good capture. However, and this is very important to note as many people get this wrong, if you were to print both images large, lets say 24x36 inches to try to show the diffraction effect, and then compare the two prints, one from a 40D at f/16 and then one from a 50D at f/16, the 50D would not look any softer! Any softening due to diffraction would be identical on an identical sized print – diffraction is strictly a lens issue and has nothing at all to due with the sensor itself. A higher resolution sensor will show it more readily since there are simply more pixels spread across the blur radius, so at 100% view, having more pixels means the blur is spread larger on your monitor as well. However what diffraction will do, if you are not careful, is limit your ability to print much larger images with the 50D. If you want to make sharp prints that are significantly larger than you would from a 40D, you will need to use a sharp lens at f/11 or less to get the most out of all those megapixels. This is a somewhat complex topic (and I still may not have explained it adequately well), so feel free to call if my above explanation was not clear. So to sum up, as far as resolution goes, one can get stunningly good results if careful technique is followed. Despite having the smallest pixels of any Canon digital SLR ever made, the camera still does not out-resolve good lenses as some people have speculated. And even if careful technique is not followed, the results will certainly be no worse than what one would get from a 40D, 30D or 20D. Okay, so that was resolution and diffraction. So now how about Canon's claim of 1-1.5 stops less noise at high ISOs than the 40D? Well... now there's a very good question. Let me put it this way: if you are shooting JPEGs with the default settings on the camera then yes, a 40D at its default settings will appear just a little noisier. However, this improvement does not appear to come from an inherently less noisy sensor, rather Canon is using some very sophisticated noise processing to clean up those high ISO JPEG files. If you are shooting raw and are using a third-party RAW converter that can reveal the “true” output from the sensor, then it seems as though the 50D is no improvement, from a pixel-level noise standpoint, when compared to the 40D. Now keep in mind that when examining a file at 100% for pixel level noise, the 50D file will appear that much more magnified than the 40D. Again, make the same size print from both cameras, and the 50D may actually look a little less noisy that the 40D, or at the very least, the 50D file will have a tighter, finer-grained noise. So all in all, still a pretty impressive performance, but based on Canon's optimistic marketing, I was definitely expecting a little better. The only aspect of the 50D's image quality that I found truly disappointing was noise in long time exposures at night. On my previous cameras (30D and 40D), I could easily do a 20 minute exposure at ISO 400 and get a very useable result. The few hot pixels were easy to clean up in post-processing. Not so with the 50D: a 20 minute ISO 400 exposure was rendered very nearly unusable due to a flurry of intensely coloured noise. No amount of processing could rid the full resolution file of this noise, not Canon's own noise-reduction, not any third-party raw converter I tried and not even Noise Ninja could clean up the file to make it salvageable. Argh. In order to make the image even salvageable for my website, I had to resort to an esoteric raw converter that creates half-size output, thereby averaging away the noise and making the file more receptive to using Noise Ninja. Finally, as mentioned at the beginning of this image-quality section, it is said that newer firmware versions of the 50D produce much better looking output at high ISO, however I do not know if this is due to different in-camera noise-processing in the revised firmware or due to inherently cleaner output from the sensor due to tuning of other camera parameters. Getting an inherently cleaner raw file is not unheard of with firmware updates: at some point during the evolution of the Canon EOS-20D, a change was made in a firmware update that rid the 20D of its annoying habit of putting “cross-hatching” noise in the shadows of even low ISO files. Time will tell if updates to the 50D can make its raw output cleaner... and at the same time, I really do hope that time-exposures get cleaned up as well! JPEG Image Quality: Although the vast majority of my shots were in RAW, I did shoot a few JPEGs too and what I did notice right away was that Canon's in-camera high-ISO noise reduction is actually quite sophisticated and not overly damaging to real detail. While post-processing with a program like Noise-Ninja may still give better results (and offer far more control), being able to get fairly clean JPEGs at high ISO settings, right out of the camera, can be helpful when conditions force you to not shoot raw files. Also note, that apart from the highest setting, turning this NR on does not impact the speed of the camera in any way either. Other useful functions are Canon's Highlight-Tone-Priority, carried over from the 40D and also a new automatic in-camera vignetting correction that Canon calls “Peripheral Illumination Correction”. One function that seems to need some tuning however is the new Auto-Lighting-Optimizer, which is supposed to give some degree of “fill light” to dark shadows. Well even at its highest setting, I found its effect to be far too subtle to be all that useful. The Active D-Lighting that the “other guys” use, seems to be far more effective. Hopefully with some feedback, the next generation of Canon cameras will be improved. UPDATE! Canon has released firmware version 1.03 just as this article was about to “go to press” and I have done some limited testing. Unfortunately there appears to be very little change in high ISO image quality. After a few dozen careful test shots comparing the new firmware to the old, all I can see is perhaps a slight reduction in banding artifacts at 6400 and 12800 ISO. No real difference in noise levels or hot pixel speckling in 30 second dark-frame test shots. That does not bode well for my long-duration night shots unfortunately. This seems to be the case not only for raw files but JPEGs also: no major changes in noise-reduction algorithms it seems. The main reason for this firmware update seems to be to address certain rare cases of “Error 99” lockups, something I have not experienced at all on my own 50D. Software: Normally I do not bother commenting on camera manufacturer's own raw conversion software, since I generally find third party raw converters to usually have better image quality and most definitely smoother workflow, however I feel that Canon's latest Digital Photo Professional software deserves a mention this time around. Here it is: from a colour, detail rendition and a noise-reduction quality standpoint, Canon's latest DPP software is as good or better than virtually every other raw converter I have used. Pretty strong statement, right? In fact, add to the mix that DPP now has “automatic” (I'll explain later why that is in quotes) chromatic aberration, lens distortion and vignetting correction, and it just may be overall the very best one out there, period! Stronger yet... So you are probably wondering if I am now using DPP for all my raw conversions... well unfortunately the answer to that is “no”. Why not? Well it's certainly not for lack of overall image quality, as mentioned above. There are several reasons: one, is that it is horribly, tediously slow, especially when it comes to making adjustments to the raw processing parameters like noise reduction and sharpening. Even on my dual-core 2.4 Ghz MacBook Pro with 4GB of RAM, the program is positively sluggish and it is very frustrating tweaking the conversion parameters and waiting a long time for the image to update and reflect the changes. The next reason is that DPP has virtually no effective highlight-recovery tool, and that is really an important part of many raw converters these days. Having effective highlight-recovery and shadow-fill adjustments can really help salvage high-contrast files, so much so, that I rarely feel the need to do any time-consuming HDR blends these days. While Photoshop, and many other raw converters, will attempt to reconstruct blown highlights in one colour channel from the remaining one(s) that may still have detail, DPP more or less seems to give up as soon as one colour channel is clipped. Finally, there is that “quoted” word above. Those wonderful automatic corrections need to be manually set for each image. Why does Canon not have a way of defaulting them on? Chromatic aberration (CA) correction is one of those no-brainer fixes that is never detrimental to image quality when performed at the raw conversion stage - it only ever helps things. This is why it was so smart for those “other guys” (okay, I'll say it: Nikon) to put CA correction right into their cameras so that every JPEG shot has already had its CA processed out. I use CA correction all the time in Adobe Camera Raw and Lightroom, and it really can make a difference on a larger print. My overall favourite raw converter, RAW Developer, is still lacking CA correction ability as well, which is the only thing keeping it from being at the very top of the heap as far as I'm concerned. Maybe my first “strong” statements are a little bit at odds with some of my criticisms, but that really does not change the fact that DPP is now very good... and comes free with the new cameras to boot! However everyone has a different opinion on what constitutes good image quality and some may not agree with my analysis, so as they say, YMMV. (your mileage may vary) In any case, give Canon's DPP a try if you have a difficult file that is noisy, has weird colour or if you are trying to prepare a raw image for making a really big print. DPP really manages to extract a lot of fine detail out of a raw file, has very effective noise reduction, and accurate neutral colours – or punchy, if so desired. Most definitely worth a look... just don't be in too much of a hurry when you're using it! Miscellany: The formerly near useless Direct-Print button has been given a second task – it now activates Live-View also, taking that function away from the Set button in the rear control-dial – hurray! I always found it too easy to activate Live-View by accident on my 40D, so this is a very welcome change. Lens-AF-micro-adjustment, formerly limited to the 1-series pro bodies, has now found its way into the 50D. I have not yet seen a need for it, but it's nice to know it's there just in case. So there you have it: my first impressions of Canon's latest prosumer camera, the EOS-50D. For some sample images and zoomify links, please see my own website at http://www.sublimephoto.com/50D/
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