But if you are like me: shooting hundreds of hours per year, having accumulated selection of camera and studio gear, very specialized applications and so on, then you are maybe still reading this article.

I have been using different 1.6x crop Canon DSLRs since June 2003. Last year I decided to add full frame camera into my kit. Canon 5D was the choice mainly because of price and operational compability with my current 30D. I also like to have lighter cameras for traveling and hiking and prefer the smaller body size for camera handling. My primary applications for 5D are among other things: travel and stock photography, documentation of bird habitats, wildlife plants and landscapes, still life studio photography ..

As for the lens utilization 5D is a godsend for every lens I own below 100mm focal length. 17-40/4 will be now ultra wide instead of slow middle range zoom, 35/2 50/2.5 and 50/1.8 mm lenses will offer creamy smooth out of focus areas. It is now possible to use TS-E 90/2.8 tilt&shift lens where it is intended for. Sometimes 5D will be used with 500/4 IS instead of 30D, for example in situations where I can approach subject and very shallow depth of field is needed.

At web I can hear a lot of stories how you should have the most expensive lenses to take full advantage of FF, but would still suffer 'from vignetting and bad corners'. My experience has been just the opposite: cheap plastic normal primes are now performing better on all apertures I care to try. When I'm shooting at full aperture I'm much more concerned of out of focus area quality ie. 'bokeh' than few per cent light falloff at edges.

To replicate the quality of my cheap normal lenses and 5D while using my 30D would not be an easy task. I should get both wider, optically better and faster lens to maintain the dof control at the same field of view: very expensive, sometimes even downright impossible. At full aperture subject is clearly better isolated with 5D, when I'm closing down the aperture for more detail the 5D is again beating 30D picture quality.

I'm converting raw files at Digital Photo Professional 2.2.0.1 supplied with the camera. For my liking of output the software is working o.k, slight adjustments of curves and white balance are usually all that is needed before Photoshop. Since 20D the noise has been very well under control in Canon cameras I have owned, by default I'm leaving noise reduction settings to zero.

Studio setup where I tried to maintain the field of view and resolution by using different lenses and f-stop to simulate how I would solve this still life with my limited skills. The explanation and set up: The intention is to show how I would complete this short time task using 30D and 5D cameras. In real life that means for me choosing EF 35/2 (56mm ff equivalent) on 30D. Thus moving tripod slightly was necessary. On 5D I had EF 50/2.5 Macro. Also aperture was set according to focal length and crop factor.

Remind that shutter speed is erroneusly 1/100 vs 1/125, but that is propably not a practical problem since very fast flashing duration. Shooting tethered on computer, manual focus with Angle Finder C, one big softbox and 320Ws monolight. Ratios set as close as possible for both pictures on DPP adjustment curve.

Adjustments: Grey card white balanced on DPP, Save as quality 11 on Photoshop Elements. Move mouse over picture to see the explanations.

First Crop: Canon EOS 30D, 1/100s, 35mm, f13, ISO 100

Second Crop: Canon EOS 5D, 1/125s, 50mm, f16, ISO 100

Coming back to my disclaimer: picture qualitywise marginals are getting smaller and smaller as we are adding more megapixels into camera. Other benefits of FF vs. APS-C for controlling depth of field and for wide angle shooting are sometimes more visible in real life photography.

Ergonomics and operations: As a long time user of 10D, 20D and 30D: Canon 5D was familiar to use from day one. Other benefit with common operations is that they share the same batteries and charger. I use them now paired and backing up each other on trips. 30D and 5D are not what you are looking for high speed action or shooting in rainforest for weeks during wet season. But for anything else those cameras are not letting you down very easily. I have been using a single camera body for weeks of traveling with some occuring of downpours, lots of freezing conditions and at the worst soaking my camera in wet mud by felling down with tripod, so I trust I will manage a trip with two of them.

As said, 30D and 5D share a lot in ergonomics. The main difference in my opinion is in the big and bright viewfinder of 5D. Built-in flash has been removed in favor of bigger viewfinder prism. 5D picture is covering 96% of frame and to my eye the view is bigger, brighter an nicer to look compared to the same field of view lens on 30D

Mirror lock-up button: Many landscape and still life aficionados have been asking mirror lock-up button for years and they were quite sour when also 5D came without one. Now I'm not following their logic! 5D is coming with 'C' mode for user registered settings which are including custom functions. You set all you like, then select 'Register camera settings' from menu and have your mirror lock-up settings in memory permamently.

When you are using, for example aperture priority, and hand holding camera at ISO 200 , automatic white balance, ai-servo mode etc. but decide that you need to shoot with tripod: just turn Exposure Mode dial into 'C' and you instantly have ISO 100, self timer lock, full manual mode with f16 and 1/4s, mirror lock-up, whatever. After shot you unload camera from tripod and return back to previoius settings just by turning dial back to Av. Much more effective than separate button for one setting that in real life requires typically several other adjustments. Also I'm not in fond of situation where one button by accident turns my camera to raise mirror to block viewfinder instead of taking the picture..

Room for improvement: I would like the camera to become even smaller, towards 30D size. But I understand that the camera size is very sensitive subject and there are other photographers looking for bigger camera size ;)

I prefer to focus manually over 95% of my work with 5D, so it is crucial that viewfinder eye adjustment knob should not move accidentally during transportation or using camera. Now it's moving now and then, very irritating!

Conclusion: Based on two Months of using camera I'm warmly recommending 5D for most serious applications you could imagine for a 3 frames per second semi-professional digital slr.