Monday, November 21, 2011

-10

The scale to fine tune the auto focus for a lens ranges from -20 to +20. I had to adjust by -10 for my 35mm lens. -10!

Here's my unsophisticated set-up:

nov21aa

Here is the first picture that I took with an f stop of 2.0. (I enlarged the picture for your viewing pleasure.) I was focused directly on the 5.

nov21a

As you can see, the focus fell on the 6 and into the 7.

Here's the same shot (f stop was 2.2) with the auto focus adjusted by -10.

nov21b

Here's Tiger with the focal point on his right eye.

nov21c

I think I need to find a replacement because my warm, fuzzy feeling with this lens is gone. Does anyone have a Sigma 30mm f/1.8? Bueller? Bueller?

3 comments:

Jen said...

Don't have it, but I've heard amazing things. I'm hoping to get one within the next month.

Cody said...

Hey Sarah, my wife mentioned you asked about the Sigma 30mm (it's f/1.4 rather than f/1.8), so I thought I'd come leave a comment. I've had it for 4 years now, and it's still my favorite lens. I've actually owned 2 of them now, one when I had Olympus, then bought it again when I switched brands. Here's some shots I took of our boys just a few days ago with it.

Question is, though, if you can adjust for backfocus on your camera, why replace your 35mm? I have a few lenses that back & front focus a bit, but until recently when I got a new camera, I couldn't adjust and just had to live with it. Now on my new camera they're all adjusted and work great. (by the way, here's a good test chart.

Sarah said...

Cody - thank you so much for responding. I knew it was a 1.4 - I must have been so tired, I typed 1.8. You know how that goes w/ triplets...

Thank you for the link for that chart.

I'll have to see how my shooting goes now that I have calibrated but I feel like the focus issue was inconsistent. I was trying to find an alternative lens just in case I need to replace asap.