Firstly the differences between the A7 and A7r as outlined by Dpreview.
The a7 and a7R are identical in terms of physical design, with the main differences being the sensor and autofocus system. The a7 features a full-frame 24 megapixel CMOS, while the a7R has a 36 megapixel CMOS sensor with no optical low-pass filter. The a7 uses a Hybrid AF system (with on-chip phase detection) similar to the one found on the NEX-6, while the a7R has traditional contrast detection. The a7 is also capable of electronic first curtain mode, which allows for a quieter shutter, and reduces the potential for 'shutter shock' vibration; this is absent from the a7R. Both cameras use Sony's latest Bionz X processor and also have XGA electronic viewfinders, tilting LCDs, Wi-Fi, and weatherproof bodies that resemble that of the Olympus E-M1.
Here's a quick summary of the differences between the a7 and a7R:
|MSRP (body only)||$1699||$2299|
|Sensor||24.3 megapixel||36.3 megapixel|
|Optical low-pass filter||Yes||No|
|AF system||Hybrid AF||Contrast detect|
|Front panel construction||Composite||Magnesium alloy|
|Electronic first curtain||Yes||No|
|Continuous shooting||5 fps||4 fps|
|Flash x-sync||1/250 sec||1/160 sec|
|Weight (loaded)||474 g||465 g|
In reality I can't discern any difference in terms of build quality, I can't say I've noticed much difference in terms of AF speed and at high ISO's the cameras are VERY similar. The A7 shutter is quieter however.
So cheaper and less pixels basically.
Now the A7 takes a decent picture.
What happens to it when the A7s is released is difficult to assess, since that and the A7r would make a very useful pair of cameras with a wide range of options and uses between them, leaving the A7 somewhat in the middle as neither one thing or the other. But then I think that is unfair. It IS obviously a useful camera for me, just from the amount I use it and when compared to what might be considered it's competitors in the 24MP 35mm film sized sensor market, of which there aren't many to be honest, in terms of IQ it's arguably the best. It's certainly better, in my opinion, for that than the Nikon D600 I had for my purposes, though the Nikon is probably better at high ISO's.
So it is a good camera, it does have it's own niche and it does what I ask of it. It may not quite have the ability to produce files quite as impressive as those from the A7r, but it's a very capable camera in it's own right. And yes, for me, it suffers from the same operational and design deficiencies that I identify in the FE cameras, but then that's just me being picky and my particularly quirky approach to cameras shouldn't put anyone else off considering it.
If you can live with the lens void and you aren't planning on sneaking up on anyone to take their picture anytime soon (because it's quieter than the A7r but still has a noisy shutter) then it could be a camera to consider if you are looking for high quality files in a smaller lighter package than a DSLR. I imagine mine will be on the shelf for a while now, since I've decided not to sell it. (At least for the foreseeable future. Which in my case means I should still have it tomorrow morning. Though don't bet your mortgage on it!!)
Please note that opinions expressed in this blog are just that, opinions. What is written here is at no time intended as a recommendation or otherwise of photographic gear or practice. This is a personal blog written 'in the moment' and is primarily intended as an entertainment. I would also point out that this is not a review site and not intended to be so and the Google+ groups where you can post comments are not forums. I am the sole moderator and I will remove any post (and poster) if I think fit.
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