Canon EOS 50D Review




After a year of watching Nikon steal the headlines with the D300, D3 and D700, Canon is back, with the EOS 50D. Amongst other refinements, the 50D features the highest resolution ever for an APS-C format DSLR (15.1 million pixels), a newly designed 3in LCD screen with a 920,000 dot resolution that matches the best from Nikon and Sony, and a greatly improved Live View system, which features Face Detection.

In use, the most obvious difference between the EOS 50D and the EOS 40D (one of the only differences in fact, as far as handling is concerned) is the improved LCD screen.





The extra resolution, and the addition of three anti-reflective coatings makes a huge difference to clarity and visibility in both bright and poor light. Arguably, the EOS 50D is the first Canon DSLR that really shows sharp images as properly sharp on the LCD, which makes checking critical focus in playback much easier than it was in the past.



A tangential benefit of the extra resolution is that the Live View image is much crisper, especially when the 5x and 10x magnification options are selected, for fine-tuning manual focus.


Technologies Explained

CMOS
Canon’s CMOS technology is one of the company’s key competitive advantages, with noise reduction circuitry at each pixel site delivering virtually noise-free images. In comparison with CCD technology, the lower power consumption characteristics of Canon’s CMOS sensors also contribute to longer battery life.

Signal conversion in Canon’s CMOS sensors is handled by individual amplifiers at each pixel site. Unnecessary charge transfer operations are avoided, vastly speeding up the process of getting signal to the image processor. Noise generation is reduced, power consumption is limited and faster frame rate potential is increased.



DIGIC
Image data captured by the CMOS sensor is processed by Canon’s purpose-built DIGIC image processors before being written to the camera's memory card. DIGIC technology uses advanced image processing algorithms to ensure precise, natural colours, accurate white balance, and advanced noise reduction. Ultra-fast processing speeds result in highly responsive camera operation and near-instant start-up times.

DIGIC chips work with a high speed DDR-SDRAM image buffer – reading, processing, compressing and writing image data fast enough to keep the buffer clear during long continuous shooting bursts. And because DIGIC integrates all key processing functions, power consumption is kept to a minimum.

EOS Integrated Cleaning System
The EOS Integrated Cleaning System combats sensor dust in three important ways: Reduce, Repel and Remove.


1. Reduce - Internal camera mechanisms are designed to minimise dust generation. The redesigned body cap prevents dust generation through wear on the cap itself.

2. Repel - Anti-static technologies, including a special fluorine coating, are applied to the low-pass filter covering the front of the sensor so as not to attract dust.

3. Remove - A Self-Cleaning Sensor Unit uses hi-frequency vibrations to shake dust from the infrared filter for a period of approximately one second after each start up. For instant shooting after power up, this feature is disabled immediately the shutter release is depressed.

Canon has also developed an internal Dust Delete Data system, which can map the position of visible dust on the sensor. This can then be deleted automatically after the shoot with the latest Digital Photo Professional software.

Picture Style
Picture Style pre-sets simplify in-camera control over image qualities. Picture Style pre-sets can be likened to different film types – each one offering a different colour response. Within each selectable pre-set, photographers have control over sharpness, contrast, colour tone and saturation. The camera’s factory default configuration is set to deliver immediately-usable JPEG images without need for additional menu settings. Picture Style presets applied to a RAW image can be revised with Canon’s Digital Photo Professional software.





Features at a glance:

* 15.1 Megapixel APS-C CMOS sensor
* 6.3fps continuous shooting, max. burst 90 JPEGs with UDMA card
* DIGIC 4 processor
* ISO 100-3200, expandable to 12800
* 9-point wide area AF
* 3.0” Clear View VGA LCD with Live View mode & Face Detection Live AF
* Magnesium alloy body, with environmental protection
* EOS Integrated Cleaning System
* HDMI connection for high quality viewing and playback on a High Definition TV
* Full compatibility with Canon EF and EF-S lenses and EX-series Speedlites


Outstanding, clean images


A newly designed 15.1 Megapixel CMOS sensor delivers ultra-detailed, low-noise images – ideal for large-scale reproduction or creative cropping. New manufacturing processes, plus redesigned photo diodes and microlenses, extend the light gathering capabilities of the sensor – allowing more pixels to be fitted on the CMOS sensor without compromising image quality. These changes ensure improved high ISO performance and low noise. High-speed, low light shooting is enabled by ISO levels of 3200, expandable to an ultra-sensitive 12800.

The EOS Integrated Cleaning System – including the improved Self Cleaning Sensor Unit with a new fluorine coating – increases protection of image quality by helping to reduce, repel and remove unwanted dust from the sensor. Stubborn particles can be removed automatically in post-production with Dust Delete Data and Canon’s included Digital Photo Professional software.



Improved interface

Still on the subject of the screen, the menu system of the EOS 50D not only looks better now than it did in the 40D, it is also better organised, and a new 'Quick Control Screen', activated by pressing the AF selection joystick in, offers immediate access to the camera's key settings.

The only function that I really wish was better signposted is mirror lock-up, which is critical for long-exposure and macro shots, yet remains stubbornly buried in a custom function menu.

The AF and metering systems of the EOS 40D and 50D are effectively the same, and the 9-point AF system is very reliable in most situations, although noticeably less positive in very low light than the 45-point system offered in the EOS 1D/s Mark III.

Improved white balance

As far as metering is concerned, highlight detail is well-preserved in scenes that feature large bright areas (like a landscape on a cloudy day) but can be lost if midtones or dark shades make up the majority of the image captured. In the rare instances where evaluative metering doesn't deliver the desired result, 'spot' metering (3.8%) and partial metering modes are available for more precise exposure measurement.



White balance seems a little improved from the EOS 40D, but this is an impression, rather than a proven (or provable) fact. Warm evening and morning sunlight can be somewhat 'overneutralised', but in general, AWB can be relied upon to deliver pleasing colours in most situations.

With strong colour casts - especially those caused by artificial lighting - a custom white balance setting is the only way to go for maximum accuracy, but this is true of all automatic white balance systems.

So the EOS 50D improves on the EOS 40D in terms of handling, and offers refined functionality and a better interface - are the images any better.






You'll need a good lens


Well, yes and no. Yes because with 50% more pixels, in optimal lighting conditions the new sensor was bound to record more detail, and it does. Resolution is clearly higher than the EOS 40D, although the 50D is proportionally more punishing of poor lenses, and the kit option 18-55mm EF-S f/3.5-5.6 IS for example is a poor companion for the sensor.

In decent light, with a good lens attached, the EOS 50D is Canon's best performing APS-C format DSLR yet. Unfortunately, the smaller pixels mean that noise does become noticeable at ISO settings above ISO 400, even in JPEG files.

With in-camera noise reduction turned off, chroma (colour) noise is just visible in areas of fine detail at ISO 400, and increases to unpleasant levels by ISO 2000, getting worse until by ISO 12,800 you may as well photograph a pile of Smarties.

Banding is a problem

Activating in-camera noise reduction helps (the EOS 50D features four levels of noise reduction, from 'off' to 'heavy'), and even at ISO 6400 and 12,800, JPEG files still give the impression of adequate (if not particularly good) detail resolution, because chroma noise is flattened into mush in areas that don't really matter - ie areas of even tone.

Unfortunately, banding is harder to conceal, and even at ISO 1600, some banding is apparent, sneaking into midtone and shadow areas, especially in the blue channel. Shooting in raw is a very good idea at ISO settings of 3200 and above, because the supplied Digital Photo Professional software does an extremely good job of automatically reducing noise levels whilst keeping the impression of sharpness fairly high, but if you prefer to use Adobe's Camera Raw (with Photoshop) you're in for a nasty surprise.

Whereas files from the Nikon D300 and D90 can quickly be rendered perfectly acceptable at their maximum extension ISO setting of ISO 6400, those from the Canon EOS 50D look nasty in comparison, and using ACR 4.6 (beta) I struggled to reduce noise to the point where it was genuinely inoffensive.

That said, anyone that intends to make small prints of A4 or less is unlikely to be bothered by noise levels up to ISO 2000, which many people - myself included - would regard as perfectly acceptable performance from an enthusiasts' DSLR.

Conclusion

The problem here is one of Canon's own making. By giving the EOS 50D a maximum ISO setting of 12,800, Canon is effectively claiming to outperform the Nikon D300 in low light, and in the same breath, implying that it can compete with other cameras which go that high, like the Nikon D3 and D700.

It cannot. What the EOS 5OD can do, however, it does very well, and the increased resolution and more advanced functionality makes it Canon's best mid-range DSLR yet. I expect it to be around £1000 by Christmas, and at that point, the 50D will be extremely competitive. If the closely related EOS 40D slips below £500 though, it may yet prove the more attractive camera.




source : http://geekspotz.blogspot.com/


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