« on: August 30, 2014, 11:03:53 AM »
This stuff just gets too technical for me, so let me ask a question.
I'm standing on the side of the road on a sunny day and I'm looking at a bald eagle that is 75 meters away sitting at the top of a tree. In my camera bag is my 300mm 2.8 lens, a 7D and 5D3.
I'm shooting handheld. I don't dare move closer for fear that I scare him off.
If I'm trying to produce a final/edited image that "fills the frame" with as much detail, sharpness, and overall IQ as possible, which body do I attach to the 300mm?
A fully grown bald eagle is 1 m long. The size of the image on the sensor for a 300mm lens 75 m away is 4 mm. corresponding to 930 pixels on the 7D or 640 on the 5DIII. 300mm is too short for a decent image. I would use the 300 mm + 2xTC on either camera as 1860 px on the 7D or 1280 on the 5DIII would give an excellent image. You didn't have the 2xTC in your bag, I know but that is bad planning.
Alan, my friend...I'm laughing now, didn't you see the part where I said "too technical for me".
It's a hypothetical situation. Which body should I grab?
OK I'll leave out the technical stuff for you: 75 m is too far away for a 300mm for good photos of anything smaller than an ostrich so my answer is grab neither and just enjoy looking at the eagle. But, if all you want is to publish a thumbnail on the web, it won't make much difference whatever you choose.