I have a been a 7D shooter and before that I used a 40D. A few weeks ago I put my money down on a 6D after getting sick of reading all the comments about what a step up in IQ it is from APS-C to 35mm sensor
My plan is to sell one of the 7D or 6D (I don't think I can justify having 2 DSLR bodies!) but I haven't decided which yet. Unfortunately I've been very busy in the last few weeks so haven't had a chance to do much 6D testing yet but hear are some initial reactions. Will see if my views change once I get a chance to play with the 6D more.
Things I don't
like about the 6D:
- lack of joystick for selecting AF points. On the 7D/40D, it was easy and comfortable to select the AF point with my eye to the VF and my right hand firmly on the camera and ready to take a photo. With the 6D I have to relax the grip on the camera with my right hand so I can move my thumb down to the D-pad to select an AF point, then move my thumb back up to the AF-ON button to AF (I prefer back button focus to using a half press of the shutter button). It's slow and uncomfortable and more likely to lead to the camera being dropped - and it's hard to be confident you're getting your thumb in the right place when you're eye is to the VF although perhaps with practice that will cease to be an issue. My initial reaction is this is one of my greatest complaints about the 6D.
- so far the AF system feels a real step down from the 7D in relation to (a) tracking moving targets, (b) limited number of AF points means focusing on an off-centre subject when shooting with very shallow DOF is a problem, (c) speed/accuracy of the AF points other than the centre point (although I'm very impressed with the centre point!). I really don't feel like I've investigated the 6D's AF enough yet and tested it in real world shooting to be sure of my opinions about it though. I do see others saying the 6D AF really isn't that bad in the real world once you get to know it and set it up properly.
- lower maximum FPS: I do sometimes shoot sports/action, and occasionally have a go at BIF, and I know there would be times when the step down from 8 FPS to 4.5 FPS would bug me. However I don't do that sort of shooting very often really so I'll need to decide how big a deal this is for me in practice. It may depend in part on what I decide about the AF - the real question may be about how many "keepers" (in terms of focus) I can expect when shooting a moving target.
- fewer functions available via the buttons on the top of the camera (because it's one function per button rather than 2 as it is on 7D/40D). I'd prefer to have FEC and WB available that way, but not sure how much this is really going to bother me.
- button layout on the back of the camera - I preferred having a column of buttons on the left side of the rear screen because it means easy two handed operation of the system of buttons plus direct access to a few more functions. Again, not sure how much this is really going to bother me.
- lack of built in flash. Yes I know how much better an external flash (and better yet, off camera flash) is, but sometimes when travelling around I like to have a built in flash for a bit of fill flash - it can be a lot better than nothing.
- lack of wireless flash trigger. Of course you can add one, but it's more money to spend and another gadget to carry. If I keep the 6D, I dare say I'll spring for some Yongnuo 622C transceivers and see how they go. The Canon RT flash gear sounds great but it's more money than I want to spend right now.
- lower X-sync speed - although again I'm not sure how much this is really going to bother me in practice. (There's also the issue of shutter speed limit being 1/4000 instead of 1/8000 but to be honest I doubt that's going to bother me at all.)
Things I do
like about the 6D
- little bit smaller and lighter - I like the feel of it, especially with a small-ish / light-ish prime lens on it ... 6D + 40 2.8 does make a pretty compact little package. That said, I do want to test more with bigger/lenses to see what the balance is like. Haven't yet put my 70-200 2.8 IS on it, but I will!
- assuming it gets focus (via AF or manual) it does produce very nice images. That said, I have to say I was a little underwhelmed at first - I didn't see the big jump up in IQ I was expecting, even at ISO 6400. Putting RAW images through LR4, I have to say I feel like I may not have given my 7D as much credit as it deserved for its IQ at higher ISOs. Don't get me wrong, the 6D is definitely a step up - and of course it goes to (usable) ISOs which the 7D simply doesn't have - but I've been surprised at what I could do with the 7D images with a bit of PP. I dare say a professional may be harsher on the 7D images than I am. Anyway, I want to do a lot more testing in varying lighting conditions before I come to any real conclusions. I have recently taken a few photos of people in more subtle lighting conditions and feel like there really was a very noticeable jump in IQ. They weren't very "scientific" tests so I will do more, but it makes me think I might come around to the IQ being a substantial step up.
- ability to get shallower DOF ... although again, so far I haven't found this as noticeable as I thought I might. More testing required though!
- for some reason I'm liking using lenses at their 35mm FOV - not sure if that is just psychological though! On my 7D I often use a Canon 28 1.8 as a small/light walk around lens and it's fine, but I'm enjoying using my Sigma 50 1.4 and Canon 40 2.8 in that role with the 6D. Will see if it's just a novelty which wears off. (By the way, to anyone with an APS-C sensor camera, I'd say definitely consider adding a 28 1.8 to your kit if you don't have one. It's not perfect but I think it gives pretty good results for a small, light, fairly cheap lens. Anyway, that's a whole other topic.)
As for the bells and whistles - GPS and wifi - I haven't played with them yet. Can't say I feel excited by either, personally, and I really doubt I'll make use of the GPS given it drains battery. Will give the wifi function a go one of these days, no doubt. My overwhelming feeling is I'd prefer Canon had included a flash and/or remote flash trigger than GPS and wifi, but no doubt not everyone will feel the same about that.
So, at the moment I'd say the 7D is the more "complete" all round camera but for me the question remains whether the 6D offers IQ benefits (and slight weight/size benefits - I use my camera a lot when travelling) which outweigh its "real world" limitations for my use. My biggest concerns about the 6D are the lack of joystick and the AF. Btw, for my use = "general purpose" camera for portraits (candid more often than posed/studio style), street, landscape, family events and some sports/action. Might try macro one of these days.
Will see how I feel after a few more weeks of playing with the 6D!