Ok, so I got my 1Dx III. And this is not the first time I have used or even owned it. And while I absolutely LOVE this body for what it does, and quite likely I will keep it. Part of me still kinda not sure about the R3 and whether I should swap it out for one of those instead.
Or alternatively hold out for the R1.
With the 1Dx III in front of me it does bring out some of the advantages and disadvantages of the body. And I think it does fit me well right now, with the only real big thing for me would be RF lens compatibility being one of the biggest drawbacks to the 1Dx III. But there are several little things that I do really like about the 1Dx III.
But the advantages that stick out while fondling the 1Dx III;
EF body, I don't know about you but I have always liked these bodies a lot and having used them extensively I do like it a lot better than R3 from a format/aesthetic standpoint. But super subjective and not a deal breaker. But I do like it quite a bit.
Fast mechanical shutter, this is actually a very important feature for me as I will be shooting in situations where jello does show up. Fast action/sports. 20fps vs 12fps is very big for me.
LONG battery life, not the end of the world. But sometimes I will be shooting 8k to 10k shots in a session. I can get 2k to 3k shots on a battery vs maybe 300 to 500 depending on the mode and how much AF action I'm doing. Having to deal with substantially less battery changes and much fewer batteries is a nice plus for the 1Dx III. And a cost savings.
Higher ISO, yes I do use 800k ISO for very select applications. With DXO's incredible AI noise reduction it makes acceptable webized images.
Not a huge deal but dialing in the FPS is something I like doing, since I don't always need a blistering 20fps. Being able to dial it down to what I want is nice, R3 is just 30fps or 15. A lot of times I set it to 10 or 12 or 8 ect. Not a deal breaker but I use this feature a fair amount.
Dual CF Express cards are very nice, I recently lost virtually an entire senior photo shoot do to a corrupt card. Customer went and had it redone by someone else. Worse yet it was a friend! So I appreciate this A LOT!!!! Not quite a deal breaker, but it's a big plus for me. And the other photographer did a much worse job than me. But at least he got them images I didn't. Lesson learned.
This might be the biggest thing for me, and what swayed me with the 1Dx III in the end, unlimited buffer depth. I sometimes shoot burst in succession a lot, I run out of buffer very easily. It can also limit what I do and have to time myself a lot more. Having an unlimited buffer has been a HUGE boon for me. One such instance is I shoot marathon runners, I can outrun the buffer quickly on just about anything, I can work around it. But not having to worry about it is SOOOOO nice and pretty much why I chose the 1Dx III in the end. It just makes you feel like there is nothing you couldn't capture. LOL.
Disadvantages of the 1Dx III;
Lower FPS in. Truth be told 10fps would do most of what I want, 16 is already fantastic and 20 just blows me away. I really don't need more than that. 30fps is just an insane amount of frame rate for me. But nonetheless it is a disadvantage.
Not an RF mount. This may be an issue for me as some of my favorite portrait lenses are amazing in the RF mount and the new super telephoto lenses are very much in my sights. But probably a ways away. So I may get my moneys worth out of the 1Dx III. But this is a big advantage.
Not and advantage or disadvantage compared to the R3. Because I don't know the answer to this. But which has better AF. I know shooting side by side with the R5 the 1Dx III has a decided advantage in the AF department especially with the 85mm f/1.2 equivalents of both systems. The RF is by far faster, but I have the darndest time hitting absolutely perfect focus. It basically doesn't, usually focuses on the eye lashes or the wrinkles around the eye, almost never the iris. Masks completely mess with it or glasses. 1Dx III is FAR FAR FAR better in this regard, even though it is much slower because of the older EF 85mm prime. It usually nails it every time no matter what. Huge difference. And since the R3 AF is more similar than different, I'm leaning towards it still not being as good. Maybe I'll rent one when it becomes available and record my findings.
That's the only disadvantages that concern me really, maybe resolution. But 4mp really is barely noticeable. Both are pretty much the same to my eye in terms of noise levels. I couldn't tell a difference on the DP review samples. If there is a difference it doesn't bother me one way or the other. IBIS is nice, but I would really have to try it with an R3 to make up my mind for sure. I didn't really notice it in my typical shooting when using the R5. Partly because when I was using it, it was portraits and primes. I had plenty high shutter speeds anyway.
As you can see not a lot that bothers me with the 1Dx III besides it being an EF body vs RF body. This definitely is a bit of a personal choice matter as I am pretty happy with 99% of EF lenses and the RF mount doesn't have a lot of lenses yet. So I would be shooting a lot of EF lenses still via an adapter. But the ones that are available are nothing short of outstanding!
There are a lot of experienced photogs here that could definitely bring up some good talking points on this matter, both are EXTREMLY nice bodies and I feel so privileged to be able to own either.
What you guys think? I think there could be some good conversations and some plusses and minuses comparing these two awesome bodies! And maybe you can bring up enough good points or logic to switch to mirrorless.
For higher resolution work I did end up getting the 5Ds R, also as a body for the wifey as she has gotten bit by the photography bug and really wanted a body she loved, especially from a size and weight standpoint. She definitely loves it to death. Paired it with the 24-70mm f/2.8 II. Not crazy heavy but insane overall IQ!
My ideal body probably would be the R1, but it's not available and I am doing a lot more shooting so I kinda need something now. Besides a lot of work doesn't need high resolution all the time. But I would still prefer to have a fast pro body with high resolution when that becomes a reality.