5D Mark IV Canon Shooters Full Frame Dilemma

The New Sensor and Processor?

If you own a full frame Canon and a collection of wonderful lenses then the latest upgrades does present a dilemma. First the latest 5D Mark IV took 4 years to arrive, unlike other manufacturers who appear to be revolutionising the camera industry yearly and sometimes more frequently. Then you discover that the processor might be a tweaked Digic 6 with a “+” added on to the end of it so it can switch quickly to video. Now if your primary work is in stills then this is worrying. Which draws into question the sensor is it new or has it also just been tweaked. A quick visit to a review site and you discover yes indeed it is the best sensor Canon has ever produced, but then you discover they are still behind Nikon, Fuji and Sony in terms of dynamic range, colour and noise.
A quick comparison from the DXO testing site is found below, the X-T2/X-Pro2 have not been tested yet:
Courtesy of DXOmark

The New Autofocus and FPS

The new autofocus engine on the new Canon is 41 cross points with 61 point autofocus, but wait even Nikon’s APSC camera has 153 autofocus points, Sony’s mirrorless full frame AR7 II has 399 autofocus points, Fuji’s X-T2 has 321 and Sony’s A99 II has 399 autofocus points. Anyone who has seen the A99 presentation of a camera shooting 42 megapixels tack sharp images at 12 frames per second, would realize that Canon may well be bringing up the rear guard with their focusing technology. So we can forget even discussing the 7 frames per second of the Canon camera does even though it is 2 fps faster than last years Sony A series or the Nikon 800 series. But keep in mind that the new Nikon D500 is 10 fps and the Fuji X-T2 is 8 fps. Yes, I know these last two cameras are APSC cameras but if you look at the resolution test, especially from the X-T2 (except at extreme ISOs) it is of similar image quality.

Falling Back on the Lenses

Well, of course, the fall back here is the lenses are excellent and the lens stable is large, after all, you date your camera but marry your lenses. What could be better than shooting on Canon lenses, they have great glass? It is really more important to have good glass than anything else. So let us look at two trusted lens testing sights for an evaluation of prime lenses.
Although some of the sites have not caught up to the new lenses that have been produced over the last few years, it does seem the Canon lens are not testing as well as other brands.

How About Cost and Weight?

Well in this regard the comparisons show that the Canon kit might be the cheapest full frame kit but only by a few hundred dollars over the Sony kit. When you are spending this much money to go full frame the difference is meaningless. Especially when the Sony kit contains a better camera and some of the best glass on the market. If you are going to go full frame it would make no sense to keep investing in a new Canon camera.
If you are going to travel given the extremely high quality of the Fuji lenses it might make some sense to look at this kit, after all, the weight and price are half that of a full frame camera! A little googling will come up with a plethora of full frame pros that have gone Fuji especially for field work.

Side by Side Comparision

Here all three cameras in the same order as above with a 35mm lens attached.

Conclusion

Given the quality of the lenses, the low level of camera innovation and the quality all round compared to other choices, it would make some sense to liquidate a Canon system before the news gets around, that even Nikon is out producing better lenses and cameras. 
The good news is glass retains a high degree of value and the cost of moving over to another full frame system might be around 40% of what it might costs if you sell off your camera and lenses. Given how far ahead the mirrorless cameras are now it might make a lot of sense to buy into a mirrorless system and really there are only two choices here, Sony full frame A7 series or the Fujifilm APSC X series. 
Sony provides excellent choices of three full frame mirrorless cameras the A7S II which is the best low light camera on the market and a favourite of the video world; the A7II a 24 megapixel all purpose camera; and the world’s most advanced high-resolution full frame camera the A7R II with a 42-megapixel sensor. All at prices below those of equivalent DSLRs. Not to mention the ability to use their new G master lens calibrated to a quality well above any current full frame lens or the stable of superb Zeiss Batis lenses specifically designed for the Sony A7 series.
Now if you were considering a Fuji system, which many full frame photographers are moving to because of the extremely high quality of the lenses and the X-Tran sensor which gives a boost to your resolution, then you might be able to almost do this for free. The quality of Fujifilm lenses is their best-kept secret and in most cases can run rings around the quality of full frame pro lenses.
One final note if you want to hedge you bet a simple Metabones Adaptor would allow you to keep using your Canon lenses while you explore a Sony Camera.

Canon EF Lens to E mount Smart Adapter (Mark IV)

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