MFA - or Microfocus Adjustment - makes all the difference

[Limbwalker]

Just an FYI for those who aren't familiar with this feature -

If your camera body has the ability to perform MFA (Microfocus Adjustment), take the time to learn how to use it and calibrate all your lenses.

Especially if you are shooting telephoto lenses where the depth of field (DOF) is so shallow.

A great real-world subject to use for MFA is a barbed-wire fence. I did this the other day from the seat of my car using my 7D body and Tamron 150-600 lens.

After shooting a few sparrows, I realized I still needed to tweak my MFA for that lens a touch. The way I could tell was the barbs just behind the sparrows were razor sharp, but those under the sparrow's feet were not. Had I just had the sparrow to use as a guide, I may not have known if it was just camera shake or the bird moving slightly. But with that wire under it's feet as a guide, there was no doubt.

Shooting down a barbed wire fence will allow you to autofocus on a fencepost (A rusty T-post in my case) and then look at the wire and see where the sharpest point of focus is.

I've tried the MFA calibration sheets, and those were okay, but not nearly as simple to me as shooting down a barbed-wire fence under real-world conditions.

Try it out. You may just find you need to dial in a bit more correction on your body/lens combo.

I'll post some pics when I get the chance to really illustrate what I'm talking about.

John

[Bill M]

I have been wanting to do this on the 70D but just haven't yet. It's not available on the 60D.

[Limbwalker]

Yea, I was surprised my 50D had it, and then they left it off the 60D. My old Tamron 200-500 was spot-on. No MFA required. This new one is close, but benefits from a little tweaking.

I think a lot of folks who think their lenses are soft just don't have the MFA set correctly.

[Casey]

I did it with the dot tune method (google it). I was happy with the results.

[Limbwalker]

Here are the images that will help me illustrate my point.

Image 1 is of a Savanna sparrow sitting on a barbed-wire fence. You can see the bird is not sharp, but the barb behind it is. If I didn't have that fence as a guide, I might have thought it was because of camera shake or a soft lens. But that was my first clue I still needed to tweak the MFA.

focustoofar by johnmagera, on Flickr

Image 2 is focused on the T-post, just to confirm what I saw. Sure enough, the post is blurry but the barb behind it is razor sharp.

focustoofar2 by johnmagera, on Flickr

Image 3 is after I tweaked the MFA to bring the focus point closer to me. Bingo! Razor sharp post and equal blur behind and in front of it along the wire.

focusjustright by johnmagera, on Flickr

[Digitalhunter]

John....what focal length is sharpest on that 150-600 lens? Is it decent at 500mm?

[Limbwalker]

DH, it's better than decent at 600. I typically shoot it at F8, but even at F6.3 it's very good.

Now that I have the MFA dialed in, it's blowing me away at how sharp it is.

That T-post in the last photo is a great example. That was hand-held from the seat of my car at about 35 feet, 600mm.

Here's a great example at 600 and F8. Again, hand-held from the seat of my car, not resting it on anything at all. This bird was probably 40 feet away. If you zoom in, you can see feather detail.

If this Tammy isn't sharp enough for you still, you'd better sell a child or take out a 2nd mortgage for a 600 F4 L

sharp sparrow by johnmagera, on Flickr

[Digitalhunter]

Looks pretty good. Didn't remember if I had asked that before or not. I have tried different combinations to get distance shots and may as well give this one a try. Appreciate the info and seeing some of the results from that lens.

[Limbwalker]

A few from today

Sandhill Cranes by johnmagera, on Flickr

Male Attwater's by johnmagera, on Flickr

[Digitalhunter]

Well done! From what I hear there can be a lot of dry trips when looking for the Attwater Prairie Chicken. I had intended to make a side trip there a couple of years ago but time didn't work out.

[Limbwalker]

Get on one of the tours. 1st Sat. of every month and each Sat. in April. Call to reserve a spot.

[Gerhard]

Awesome,

I have to learn how to do this with my 70D.

Some very cool photos you took.

[Limbwalker]

Thanks! Good luck.

They say if you use the live view option and zoom in while you're focusing, it helps, but I didn't bother with that.

There are some good tutorials on YouTube for the 70D

[HillCountryHoyt]

Thanks Limbwalker...as always I learn a lot from you and always admire your pics!