Thursday, February 19, 2009

Shoreline Birds at 400mm

This post is going to be mostly pictures and not as many words.

The Saturday after my defense (Feb 7th) I took a bike ride out to Shoreline and searched around for some birds to test my new Sigma 400mm f/5.6 APO Telemacro HSM on. I was not dissappointed and found a couple of snowy egrets, a great blue heron, geese, a hawk (not pictured since I only got it in flight at long distance), and a western grebe (I think).

As always, click on a picture to see it larger.

Most of these shots are from a snowy egret that was catching minnows or maybe crayfish in one of the drainage streams. At first I thought the bird was a bit nuts since it kept swishing its feet around and doing a little shuffling dance, then ducking its head into the water and coming up with a leaf.

Later on, I realized that the stream was full of little minnows this time of year and it was just disturbing the leaves at the bottom of the pool to stir up whatever it was eating.

A little further along I ran into a GBH. Sadly, I was a bit constrained on my angle and wasn't able to keep that leaf from behind his head (it was around the corner in the stream and I had to climb out on some sand-bags without startling it). Although, I have to admit I didn't see the leaf until I processed the image, but I don't think I would have been able to move enough to remove the leaf from the shot.

Later on, I ran across the grebe, diving in the bay. He (she?) would dive and disappear for a minute, then pop up in a new location. But he had those electric red eyes that look so cool!

The Sigma 400mm performed quite well. The weight honestly didn't bother me as much as I thought it would (in some spots I used a monopod, but most shots were hand-held). Likewise, since it was a sunny day, I didn't feel like I was banging against the limits of its light gathering ability, and most shots were at ISO 200 with a pretty high shutter speed (1/500s or shorter).

The thing that bugged me most, which is really more due to the camera, was the fact that most images were back focusing. In other words, I'd line up the center focus point on the eye of the bird, but the autofocus would focus slightly behind the bird, putting the bird's head a little out of focus. I've noticed this before on my 20D, but a 400mm lens at f/5.6 really highlights any focusing problems.

The typically thing to do for backfocusing is send the camera and lens in to the factory to be calibrating -- oftening costing $100 or more EACH. Yeah, that's not going to happen with my current photography budget. I honestly suspect my camera because I've detected the problem before. Overall, it is relatively minor (with only a slight bit of softness). As long as I'm aware of it, I can adjust the focus manually using the HSM.

Speaking of the HSM, it is really nice. With proper light, the lens focuses really fast. Definitely on par with my 70-200mm f/4's USM. I'm very glad I was able to get the HSM version and it makes clean-up of focusing problems very easy -- just focus, twitch the wheel a little forward, and shoot.

I do regret the Err 99 problem (forcing me to stay at f/5.6). The lens gives pretty sharp pictures wide open, but I know it'd sharpen up even more (and give me a larger depth of field) if I could stop it down to even f/6.3. Especially for closer subjects, that extra depth of field would be nice.

But, for $250, I'm pretty happy with the thing.

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