Canon has just announced an upgrade to their entry level Rebel dSLRs – the 550D which essentially is a cut down version of their new 7D.

Given I own both a Canon 1D Mark III and a Panasonic GH-1 Micro Four Thirds camera, a comparison of each of these cameras would be useful, although they are each on different classes of cameras – the 7D, a larger, heavier semi-pro dSLR would be better compared to the successor of the Olympus E-3 or a Nikon D300S, the 550D, an high end entry level dSLR would be better compared to the successor of the Olympus E620 or Nikon D90, while we can expect a new version of the GH-1 soon (a GH-2?) with further improved video.

Canon has finally made the Rebel series a decent photographer’s camera by at last upgrading the exposure compensation to +/- 5EV instead of the very limiting +/- 2EV but still hasn’t made it easy to do a mirror lockup to ensure sharp images which is important for exposures (even on a tripod) of 0.5 – 1/125th sec with higher magnification scenarios such as telephotos or macro – but then none of the Canon cameras allow easy mirror lockup – not even the pro bodies.

Canon has also added the much improved movie modes of the 7D adding options of 1080p at 30/25/24 fps or 720p at 50/60fps and an optional external mic and whilst it’s menu has an option to enable AF during movies, this AF will be very noisy and slow – if it works at all – unlike the case with the Panasonic GH-1 which has full, silent AF during movies with its unique step-less aperture (for nicer transitions of exposure during lighting changes) HD kit lens.

For most people the image quality of the cameras will be similar enough to be inconsequential (18mp vs 12mp is largely irrelevant although 18mp means you need 50% more space on your memory cards and computers for the same number of images and you really need high quality IS lenses or use a tripod to get that 18mp detail), although there will be differences at higher ISO – the Panasonic is likely to have more noise and more banding, although we will have to wait until someone does some direct comparisons.

Surprisingly, this comparison showed that the 7D appeared to have more noise at ISO 200 than the Olympus E-P2 and we know the GH-1 has a better sensor than the E-P2, but to my eye, the 7D does seem to be marginally better than the E-P2 at ISO 1600.

In fact, this is confirmed with the tests by DxO which showed that the GH-1 has similar dynamic range to the 7D, but in noise terms and colour sensitivity, the GH-1 OUTPERFORMS the Canon 7D up to ISO 800 and is the same at ISO 3200!

Given that there are no compelling EF-S lenses (apart from the EF-S 17-55mm f/2.8 IS lens – thanks Billy for reminding me of this one) designed to optimise the Canon cropped sensors other than perhaps the required EF-S 10-22mm ultra-wide zoom which will give you 16mm wide angle, I have not recommended a 1.6x cropped Canon dSLR in the past because, unlike Olympus and Panasonic with their Four Thirds system, Canon has refused to create pro quality lenses which optimise the cropped sensors. However, the 7D and 550D may have enough bells and whistles at a good price to make them a worthwhile buy – although I would only use EF L lenses with it if I were to buy one – the EF-S lenses just don’t get me excited, and if I were to think of using them, I may as well use my GH-1 instead.

If you do decide to get a Canon 7D, consider not wasting your money on the kit lens and do yourself a favour and consider a cheap Canon 50mm f/1.8 lens for portraits and low light work and save for a pro EF lens such as a 24-70mm f/2.8 or 70-200mm f/2.8 IS L – after all, you are prepared to buy such a big camera to get shallow depth of field and sharp images and unfortunately, the Canon kit lenses are just not going to deliver on these – see the links to the reviews in the table below.

The Panasonic 10x kit lens image quality easily beats the EF-S lenses such as the 3x 18-55mm IS, 10x 18-200mm IS or the 7.5x 18-135mm IS, and in addition, gives you silent AF and step-less diaphragm for videos as well as a non-rotating front element for ease of use of polarising filters, and better build quality (see reviews linked below).

If you decide to get a Micro Four Thirds camera, strongly consider adding the superb Panasonic 20mm f/1.7 lens.

	Canon 550D / Rebel T2i	Canon 7D	Panasonic GH-1
dimensions	129 x 98 x 62 mm	148 x 111 x 74 mm	124 x 90 x 45 mm
weight with battery price	530g $US899 with 3x kit lens	860g $US1899 with 7.5x kit lens	385g $US1220 with the awesome 10x kit lens
sensor size	18mp 1.6x crop 22.3 x 14.9 mm, 5.4 MP/cm²	18mp 1.6x crop 22.3 x 14.9 mm, 5.4 MP/cm²	12mp 2x crop 18 x 13.5 mm 5MP/cm² over-sized to allow for uncropped 16:9 and 3:2 image aspect ratios
in-built flash	Yes, GN 13m	Yes GN 12m	Yes GN 10.5m range but shadow with kit lens at 14mm
flash	sync 1/200th – can manually force increase for non-TTL external flashes HSS and remote TTL Manual flash output settings. TTL flash even with legacy lenses.	sync 1/250th – can manually force increase for non-TTL external flashes HSS and remote TTL Manual flash output settings. TTL flash even with legacy lenses.	sync 1/160th – no ability to force higher syncno manual flash output setting built-in flash ?? HSS FP flash with FL50R TTL flash with legacy lenses assumes aperture of ~f/2.8!
ISO	100-12800	100-12800	100-3200
image stabilisation	optical in some lenses	optical in some lenses	optical in some lenses works during video
movie video modes	1920×1080 .mov 30/25/24fps 1280 x 720 .mov (50/60 fps) stereo external mic port Can use Picture style filters. Manual or auto exposure modes. AF slow and noisy. No stepless aperture lenses.	1920×1080 .mov 30/25/24fps 1280 x 720 .mov (50/60 fps) stereo external mic port Can use Picture style filters. Manual or auto exposure modes. AF slow and noisy. No stepless aperture lenses.	1920×1080 AVCHD 25fps 1280×720 at 50/60fps AVCHD or motion jpeg full silent AF and stepless aperture when using HD lens. stereo mic + ext. mic port dedicated movie start/stop button – works in any camera mode, but must set mode dial to Custom Movie for manual movie mode. Optical image stabiliser in lens works. Can use film modes. Manual or auto exposure modes.
LCD	1,040,000 dots fixed 3:2 ratio;	920,000 dots fixed 4:3 ratio	460,000 dots swivel
viewfinder	95% coverage optical pentamirror, 0.87x magnification	100% coverage optical pentaprism, 1x magnification	integrated very high quality EVF but brief viewfinder blackout during burst mode
lens	3x kit lens 18-55mm IS EF-S optically not as good as the GH-1 kit lens which even covers 10x zoom, but much better than Canon’s previous non-IS kit lens but no-one would seriously want to use that old one anyway. front element rotates so polarisers are a pain to use. manual focus ring poorly designed see dpreview	7.5x kit lens 18-135mm IS EF-S Not a great lens optically – seems it is much worse than M43 kit lenses – see here	the unique HD video optimised 14-140mm lens 10x zoom – heavy and expensive but the only lens with continuous AF in HD video. see dpreview.com 20mm f/1.7 – THE extra MFT lens to get for portability, low light work.
AF issues	9 point AF central cross hair only to f/5.6 predictive AF up to 10m phase contrast AF – best for fast action, but only 9 points may be limiting in some scenarios Lenses may need to be calibrated to adjust for back-focus Face detection AF only in slow live view mode AF assist by flash.	19 point AF predictive AF up to 8m phase contrast AF – best for fast action Lenses may need to be calibrated to adjust for back-focus AF assist by flash.	faster AF but no AF on most Four Thirds lenses unless they are contrast-detect AF capable select AF-C, AF-S or MF via lever on top left. Cannot use MF to easily fine tune AF, must move lever to MF to use MF. select AF mode via button on rear. Must move lever to AF then half-press shutter or use AFL button to set AF. Lenses do NOT need to be calibrated for back focus as this is not an issue with contrast detect AF. Fast face detection or subject tracking mode – you tell camera which subject you want to track, and it will AF on that subject anywhere in the frame, even if you zoom, but only for walking speed subjects. AF assist by dedicated lamp.
Auto modes	Movie – you can use P, A, M +/- picture style P, A, S, M exposure modes	Movie – you can use P, A, M +/- picture style P, A, S, M exposure modes	iAuto – camera automatically detects scene mode to use.Scene modes – night, macro, sports, scenery, portrait, color. SCN – other Scene modes – sunset, party, baby1/2, pet. Custom Movie – allows manual exposure, even shutter speeds as slow as 0.5 sec! CUST – option of 3 custom settings P, A, S, M exposure modes
Sequential shooting/self timer	3.7fps	8fps	3.5fps; Select option via lever at top right
Fn button can be set to either:			Aspect ratio; Jpeg quality; Metering mode; i.Exposure on/off; Guideline grid; Rec Area; Remaining time/shots display;
Exposure compensation	+/- 5EV Flash exp. compensation +/- 2EV. AE bracketing 3 frames up to +/- 2EV	+/- 5EV Flash exp. compensation +/- 3EV. AE bracketing 3 frames up to +/- 3EV	+/- 3EV via front control wheel (press in to toggle in and out of exposure compensation mode) Flash exp. compensation +/- 2EV. AE bracketing 3,5 or 7 steps by either 1/3rd or 2/3rd EV.
Picture modes			Film modes – Standard, Dynamic, Nature, Smooth, Nostalgic, Vibrant, Standard B&W, Dynamic B&W, Smooth B&W, 2 My Film settings, MultiFilm. Unfortunately, cannot select a filter for B&W modes, and cannot apply a monotone toning.
Other features	shutter 30sec – 1/4000th sec may need post-processing to correct optical distortions intervalometer via USB + computer IR remote or E3 connector Live view LCD frame rate 30fps Remote live view via EOS utility	environmental sealing shutter 30sec – 1/8000th sec may need post-processing to correct optical distortions intervalometer via USB + computer no IR remote N3 connector Live view LCD frame rate 30fps Remote live view via EOS utility	shutter 60sec – 1/4000th sec in-camera optical aberration correction for Panasonic lenses. uncropped 16:9, and 3:2 image aspect ratios MF magnification automatically appears on moving MF ring on MFT and FT lenses. One button press to enter MF magnified view mode. Half-press shutter button to return. Automatic switching between LCD and EVF when place eye on EVF. Shutter speed and aperture live preview simulation. Better images at high ISO (see dpreview here) than GF1, EP1, E620 but more banding although Nik Dfine does a great job fixing this banding. ISO value is ~1/3rd less than actual (ie. at ISO 100 it should be ISO 125) Some models have problems with loose strap lugs which then may fall out unexpectedly – if you have loose lugs – perhaps send it back for repair under warranty. No IR remote. Live view LCD frame rate 60fps No remote live view.

As I said, these are 3 totally different classes of cameras.

If you really need fast action AF then the Canon 7D is clearly the winner with its added features of 8fps, 19 point phase detect AF, 100% pentaprism viewfinder and environmental sealing (although a 2nd hand Canon 1D MIII will give better image quality, better build, more AF points, 1.3x crop instead of 1.6x, smaller file sizes but no video).

If wide aperture, fill-in flash in bright sunlight for nice portraits is your priority, then the Canon 7D (or, even better, a 2nd hand Canon 1D MIII) is again the winner with its flash sync of 1/250th second, ability to over-ride the sync speed, fastest shutter of 1/8000th sec to allow wide aperture use, and of course, availability of 3rd party radio wireless flash control such as Pocket Wizards.

If video frame rates such as 30/25/24fps at 1080p is more important than ability to continuously AF during video, then either Canon is the way to go, but the GH-2 will have these capabilities too when it is announced this year.

If remote TTL flash, remote camera control, intervalometer functionality (with computer) or remote live view is a priority, then either Canon will do.

BUT, if the above are not important to you, then the many other advantages of the Panasonic GH-1 or the other Micro Four Thirds cameras may be the best option, particularly if you can compliment it with a high end dSLR (see here).

To reiterate again, the advantages of the GH-1 are:

• much smaller and lighter, especially when you take lenses into account – the BEST camera is the one you take with you and here size DOES matter – that’s why my GH-1 gets MUCH MUCH more work than my Canon 1D Mark III.
  
• continuous, silent AF during HD video
• built-in stereo mics as well as stereo mic port
• minimal rolling shutter issues in HD video
• AVCHD video compression for 3x smaller file sizes and easy viewing on video devices and the way of the future but a bit of a pain on computers at present – but at least you have the 720p motion jpeg option which I often use.
• the best quality kit lens
• the least image noise in RAW files at ISO up to 800 and the same thereafter
• ability to use almost any lens ever made (including Canon EOS), and via adapters, add tilt-shift functionality to many of them which brings back the fun into photography!
• the best live view experience:
  • fastest access to magnified view for accurate manual focus which makes legacy lens use a truly worthwhile proposition
  • excellent EVF so can hold camera to the eye to reduce camera shake and reduce effects of full sunlight
  • EVF and LCD allows display of different image aspect ratios including 16:9 and these are not just cropped images and mean that you actually get extra width from your wide angle lenses when using 16:9 ratio!
  • no clunky mirror mechanism to activate or deactivate it
  • the fastest live view AF system currently available and with fast face detection and subject tracking AF
  • automatic sensing of EVF vs LCD so it turns off the LCD when you bring your eye to the EVF
  • EVF field of view is better than cropped pentamirror viewfinders such as on 550D, and stays bright even when using stopped down apertures on legacy lenses or ND filters
• no need for cumbersome mirror lockup procedure prior to critical, high magnification shots
• flip out, swivelling LCD – great for self-portraits, macro use, tripod use, video use with mounting on a stabiliser, awkward positions and can be rotated to protect it’s screen.
• timed long exposures to 60sec instead of 30sec is handy for astrophotography – consider getting a Hutech-modified GH-1
• 2x crop factor gives the most telephoto reach for a given lens although as the pixel density of the 3 are closer, the telephoto reach advantage of the GH-1 is reduced a little.
• 16:9mm wide uncropped images using a 7-14mm lens (ie. 14mm in 35mm film terms) which will allow wider rectilinear wide angles and video than on any Canon EF-S dSLR which can only do 16mm using the EF-S 10-22mm lens, and then only in 3:2 mode for photos.

Hopefully, Panasonic will bring out a GH-2 soon which is rumoured to match the HD video rates of the Canon cameras and give 25mbps instead of 17mbps video quality as well as further improved high ISO performance and probably give us 14mp, for what that’s worth.

If use of legacy manual focus lenses is your main priority, you should also consider the Olympus Micro Four Thirds cameras such as the newly announced E-PL1 (this has the best flash functionality of all M43 cameras to date as it adds IR wireless TTL support) or the earlier E-P1 and E-P2, as these add image stabilisation to ALL of your lenses even legacy ones, and adds some nice art filters as well as having the best in-camera processing of jpegs for the nicest colours out of the camera.

See also dpreview’s articles on the 7D, 550D and GH-1.