Eye sharpness

[jkshyt]

Hey everyone,
I've been Practicing catching the eyes. I'm using an older Sigma lens, 150-500 on an e-mount body. It's slower than the e-mount lens but seems to work well.
Any pointers on the best practice for sharpness? I remember when everything was manual focus and those sports shots were tack on sharp in newspapers and magazines.
Thanks

_A747685 by jk Sullivan, on Flickr

[Geoff F]

I used that lens for several years before getting the more recent 150-600 Sport lens. But I still have my older lens as a spare.

Are you using auto focus? The potential problem with that method is that your camera often focuses on the closest sharp edged object which isn't what you wanted. For example a bit of twig or a leaf which leaves your intended subject out of focus.

Manual focusing will in many cases work out as the best option, although birds in particular tend to move around faster than I can manually focus. MF is fine for a sitting subject, particularly when it is surrounded by other bits, such as a bird on a tree branch. But for moving subjects in more open situations I often find that auto focus is the better option, although AF can be slow in these bigger lenses. Using one of the focus tracking camera options can help to retain AF on a moving subject.

Following a moving subject and continuously tweaking the manual focus until a suitable composition occurs can be a good work around.

With this particular image, I wonder about cropping a little from the right side and ending up with something around 4 x 5 ratio?

[Manfred M]

There are all kinds of issues that can impact images, especially when taken with longer focal length lenses. Geoff has listed a few of them, but there are more. You have not given us any of the other important shooting parameters; focal length, aperture, etc. to help assess this image.

Softness can also be related to shutter speed (even a slight amount of camera movement or subject movement can be problematic). While not strictly applicable to this scene, I generally use a tripod and disable the auto-stabilization feature. Being a non-Sony lens, there could be a measurement lag or error here. You do not mention the autofocus mode selected and unless you are using a single focus point of the eye itself, the autofocus using multiple focus points can be off a little.

Lenses are never all that sharp at the edges, especially at a wide aperture setting and that Sigma lens (I own one) is not known for being all that sharp, although in real life situations that is generally not an issue. The eye is not at the centre of the lens; if there are any MTF graphs available for that lens, that might be something to look at.

Thermal effects (temperature differential in the air and the ground) can reduce sharpness as can haze or humidity in the air, especially with longer focal lengths.

Those magazine shots were never that sharp anyways, we just remember them as seeming so. The offset press printing process, especially in newspapers and mass production magazines were never all that good. I seem to remember being told that the best that was achievable 20 or 30 years ago was 150 dpi in higher end magazines with newspapers being under 100 dpi. Modern digital presses can do much better.

[BobGilbody]

I agree with the comments made by Geoff and Manfred. I too had the Sigma 150-500 lens. The lens was not much good. I now use three lenses to photograph birds, Sigma 150-600 C, Sigma 120-300 f2.8, and a Sigma 70-200 f2.8. Most of the photographs I take are from my granny flat.. The birds are never more than 8m distant and often much closer.
I have perches set up and over the past three years the visiting birds have become friendly.
The important variable that determines the image quality is the light. I don't have any control of that unless I use flash.
My advice is to sell the Sigma 150-500 and get a 150-600 C. Then take lots of photos.

[jkshyt]

Yes, this was taken using auto focus, It's a little slow. The camera is a sony a7iv with an adapter. I agree 4x5 would look better. Thank you.