Need advice to improve low-light focusing technique

MikePDX wrote:

This could have alternatively been titled Mike's most disappointing shot of 2012.

First off, this shot was no way my worst of 2012. Those would be the shots of the bottom of the camera bag as I was reaching in for my camera. However, it does fall into the "near miss" category - a once in a lifetime opportunity that I wasn't able to capitalize on. So why post it here? Its primarily a way of forcing myself to study it and learn from it, so this long winded narrative may not be of interest to everyone. But for me, maybe there will be a "next time" when I can use that knowledge. So here goes:

I'll start with some things that I think are right about this image. I personally like the composition and the point of view. There was a good uncluttered background that helped with subject isolation. So I wanted it to be a real winner.

But I wish it was sharper. My test of sharpness is an 8X10 print. If that is sharp, I'm OK with the image. If I could print a sharp 11X14 I'm even happier. But this one is just not sharp, and no amount of wishing and no amount of post processing (at least within my skill set) will make it sharper.

Admittedly the conditions were right at the limits of what my equipment could handle. It was a full hour after sunset. I was still shooting well past the point where all the other people on the trip had given up. Details: E-M5 with ZD 70-300 at 300mm hand-held wide open (f/5.6) at 1/60 sec and at ISO 3200. I didn't have a tripod with me - I couldn't have afforded the weight or bulk on this trip.

So what could I have done? Well, there is the fantastic ZD 300mm lens out there that would have given me 2 full stops more light. But at nearly $7k it is well out of my price range. I looked into renting it - over $1k for the 4-week trip. Its also big and heavy and I would probably have needed a tripod, too.

When I pixel-peep at these images, I don't believe that camera shake was the problem. I have reasonable hand-holding technique and my camera's in-body image stabilization is excellent. Even so, on my next great adventure I will be taking a light weight monopod that collapses small enough to fit into my camera bag.

Here is a near 100% crop of the face which is what I focused on using S-AF and the center-weighted diamond:

I believe the problem is autofocus. It seems universally blurry - out of focus. I think it was just too dark for the autofocus to work accurately. Maybe different equipment would solve that, but I have my doubts. I need to work on my technique for very low-light focusing to see if there is something I could be doing better. I also had an E30 with 50-200 and 1.7X, but the E30 couldn't focus on this at all.

Anyone else have some good suggestions? How do you achieve very accurate focus in very low light? I couldn't have used flash, even if I had one - it might have spooked the lion. Is this simply the limit of what the 70-300 can do? If so, how could a slower native lens be any better? Should I have tried manual focus?

Thanks for the help!

--
-Mike
It's much easier to criticize than to create
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