« on: November 09, 2012, 09:17:38 AM »
I have an APS-C setup with the 7D and 10-22 and 17-55 2.8. I have considered moving to FF with the recent reduction in prices of the 5DII and the 6D being announced, but here's the dilemma:
1. I am quite happy with the IQ of the 7D up to ISO 1600, but the noise above that is bad. So indoor photography without flash suffers. That is the main reason for my FF considerations.
2. I am aware that if I move to FF, I will have to trade my EF-S lenses for FF equivalents. My lenses will hold their value and I can get the 24-105 and 17-40 without losing any money (cannot afford the 24-70 II). But while the 24-105 is very good lens, I am not so sure about the 17-40. I didn't like the copy I owned (and I used it on a 5DII as well). And, I cannot afford the 16-35 II. Additionally, if I use f/4 after moving to FF- what do I gain over using f/2.8 in APS-C?
3. I did like using the 5DII for the short time I had it and the images were very nice, especially since I almost exclusively use the center AF point, but I do use the high-speed mode a lot on my 7D and I will certainly miss it (and again, cannot afford the 5DIII).
* The stop difference between your 17-55 and its FF replacement(s) is most of the difference in high ISO between the 7D and 5D2. The 5D3 is better still, but you've ruled that out for now on price. Nobody knows what the 6D will be like, though I imagine it will be comparable to the 5D3.
* You say noise above 1600 is bad. Use Canon's DPP for high ISO shots along with a 3rd party NR plugin. With that combination I find ISO 3200 noise is difficult to detect in an 8x10 print.
* Finally, for the price and hassle of moving, why not just add a fast prime?
If you could afford the 5D3 I would say go for it. But my guess is you will miss the speed and AF of the 7D vs. the 6D. Add a fast prime and optimize your high ISO workflow.