7D vs 6d for bird photography

I currently use 7D with Canon 400 mm f5.6 L USM prime lens for shooting birds.
I am wondering if the 6D, with its more up to date FF sensor and processor, would give better results after cropping down, compared to 7D? Or would the 7D hold its own?
Any comments/feedback, especially from anyone who has used both, would be welcome.

Any chance you could stretch to the 5D3? Certainly not saying that the 6 isn't capable, but you may miss the focus ability moving from the 7D.

I have both plus a 70D. For birds, keep the 7D. Reach and AF are the reasons. I do shoot birds occasionally with my 6D, and shot a whole air show with it too with great results. Yes, IQ is better from the 6D but even that IQ difference can't make up for the 1.6x advantage the 7D has in focal length-limited situations (most bird shooting scenarios are that.) If you shoot the exact same photo with the same 400 5.6L lens, the 7D image will be better than the cropped 6D image.

I think I would be more concerned that in using the 6D, being full frame, you will lose some of the reach afforded by the 7D which is a cropped sensor. That 400mm on the 7D is giving you an effective field of view of 640 mm (1.6 x 400 = 640) whereas on the 6D it will be the field of view of 400mm. You state you are already "cropping down" so with the full frame format you will need to crop even more. I'm not certain the improved image quality of the 6D vs. the 7D offsets what you would have to do in the crop action needed.

Definitely stick with the 7D unless you have a big, big budget to work with.... It's not just the lens multiplier factor. The 7D "puts more pixels on target" than either of the 22MP full frame cameras. The 7D has more than twice the pixel sites per square mm (around 54,000 compared to around 25,000). So for most anything that calls for long telephotos, the 7D will give you superior results unless you also change lenses.

You could achieve better IQ with the 6D or 5D Mark III, but in order to do so you'd also have to trade in your 400/5.6 for a 600/4 IS or 800/5.6 IS. That's a rather expensive upgrade. Especially since you'll need a top quality tripod to put the camera and lens atop, too... Plus a backpack to move the lens around.

And, I agree, the AF system of the 6D would be a downgrade, too, compared to the 7D. The 5DIII would be more equal to the AF performance of the 7D.

You would also be going from 8 fps that the 7D offers, to 4.5 fps with 6D or 6 fps with the 5DIII.

Be patient... I bet we see a 7D Mark II sometime next year. I expect that will be a great birders' camera.

It's not the crop that affords the 'reach' of the 7D. It's the pixel density.

As a point of reference, if you take a 400mm shot of the moon with a 6D, it will be about 620 pixels wide. The 7D will give you an image that's 820 pixels wide.

Heya,

Keep the 7D for now. Great autofocus, more reach than a fullframe. No reason to change bodies at this time for birding unless you're going for an even better cropped body. Even then, I'd say save your money and get an even longer lens instead (hah).

Very best,

Ditto what everyone else has said.

I have both a 7d and 5d3 (the latter being pretty new to me) and there is no way I'm going to get rid of the 7d -- for the sort of shot you're talking about it's exactly what I reach for and will continue to.

That reach is a big deal and it's pixels-on-target that count when all is said and done. Your breath will be taken away if you try to replicate the pixels-on-target of the 7d by buying longer glass, never mind the mass and size penalty.

The feedback is unanimous - hold on to the 7D for bird shots, rather than go for 6D - the reasons listed make sense.
Also the prospect of buying expensive and heavier glass doesn't appeal to me!
Thanks to all who replied so promptly.

This isn't showing off (although I am excited, just got it!) on full frame, you would have to lug something like this along......and it still wouldn't have the reach you'll have with your current combo!

nellyle wrote in post #16478878
This isn't showing off (although I am excited, just got it!) on full frame, you would have to lug something like this along......and it still wouldn't have the reach you'll have with your current combo!

holy moly, this could be classed as regular weapon
congratz!

palad1n wrote in post #16478906
holy moly, this could be classed as regular weapon
congratz!

Thanks!

nellyle wrote in post #16478878
This isn't showing off (although I am excited, just got it!) on full frame, you would have to lug something like this along......and it still wouldn't have the reach you'll have with your current combo!

Heavens - I wouldn't be able to cope with that combo!
However I'm sure you get stunning results......

gabebalazs wrote in post #16478577
I have both plus a 70D. For birds, keep the 7D. Reach and AF are the reasons. I do shoot birds occasionally with my 6D, and shot a whole air show with it too with great results. Yes, IQ is better from the 6D but even that IQ difference can't make up for the 1.6x advantage the 7D has in focal length-limited situations (most bird shooting scenarios are that.) If you shoot the exact same photo with the same 400 5.6L lens, the 7D image will be better than the cropped 6D image.

Listen to this guy. Makes perfect sense. I would keep using 7d with 400mm 5.6.

bobbyz wrote in post #16479405
Listen to this guy. Makes perfect sense. I would keep using 7d with 400mm 5.6.

if you're mostly shooting birds just stick with the 7D