a500 focus issue?

[mmhendrie]

Guys - so I'm loving learning with my a500. But, I've sort of noticed i'm not getting really sharp shots very often. At first I put it down to me amateur status, and it might still be that, but sifting back, it does seem I was getting sharper shots with my old a230.

I tried a couple of basic things - focusing on an area of small detail and shooting, and then doing the same with manual focus, and my manual focus' are much sharper. I tried the below test I see used a lot, all be it in fairly low light, and guessing a bit at the 45' angle, but i did use a tripod and the 2 sec timer:





I'm worried I have a focus issue. Do Sony charge to have this fixed? I'm fairly handy and willing to give it a go myself, but I think I'd like to be certain as to whether problem I'm addressing is fixable with a wrench, or just with practise! Any other tests I can try? Advice/thoughts/next steps all appreciated!!

thanks,
Matt

 

[Ed at Ridersite]

There is a way to do it yourself on the older A-mount cameras. Here's a link:

http://www.dynaxdigital.com/sony-alpha-crop-sensor-camera-discussion/method-for-adjusting-backfront-focus-on-the-a700-and-other-sony-cameras/15/

Not sure if the A-500 is the same.
--
AEH
http://aehass.zenfolio.com/
Question: What do you do all week?
Answer: Mon to Fri. Nothing, Sat & Sun I rest!

 

[TrojMacReady]

There is a way to do it yourself on the older A-mount cameras. Here's a link:

http://www.dynaxdigital.com/sony-alpha-crop-sensor-camera-discussion/method-for-adjusting-backfront-focus-on-the-a700-and-other-sony-cameras/15/

Not sure if the A-500 is the same.
--

I did the adjustment on my A500 and it worked like a charm. That being said, if the camera is still under warranty, Sony does it for free and can make different adjustments for different lenses through the software (IIRC), versus the one adjustment has to fit all lenses approach with the little scews.

 

[zackiedawg]

Looks like you have a backfocus issue - as mentioned, you can send the cam to Sony to be adjusted, if you're willing to have it missing or a while, or you can do the adjustment yourself if you do it carefully and in VERY small adjustments at a time, testing as you go. The manual adjustment process is actually quite simple to access, but the screw turns are very very small to have very big effect, so best to do it very slowly and methodically. I tuned my A580's focus in about 15 minutes when I first got it, and it's been perfect ever since.

--
Justin
galleries: http://www.pbase.com/zackiedawg

 

[mmhendrie]

ok, well, I think i need a bit more guidance. I was getting ready to try the back focus adjustment, but decided to do one more round of tests with the focus sheet.

The earlier results I posted I had the camera held in portrait position, this time I positioned the camera in landscape - and the results were quite different, infact, the focus looks fine.

To test, I then positioned back in portrait, and I get similar results as my earlier post, where it indicates a back focus issue. I'm confused as to which reading to go from, and what this means?

thanks,
Matt

 

[TrojMacReady]

ok, well, I think i need a bit more guidance. I was getting ready to try the back focus adjustment, but decided to do one more round of tests with the focus sheet.

The earlier results I posted I had the camera held in portrait position, this time I positioned the camera in landscape - and the results were quite different, infact, the focus looks fine.

To test, I then positioned back in portrait, and I get similar results as my earlier post, where it indicates a back focus issue. I'm confused as to which reading to go from, and what this means?

I would double check those results with some tests on "real" subjects. Some shots of a painting or so at larger aperture in landscape and portrait mode, all from a tripod.

If its still spot on in landscape mode an not in portrait, maybe your focus sensor is tilted a bit. While fixable with the screws still, I would have that done by Sony, ymmv.

 

[mmhendrie]

the plot thickens.....

So using the focus sheet some more, keeping the camera in landscape, I tried using some of the other focus points to check results - before i could, something more interesting (or troubling happened) - I can only get the focus to lock on 5 of the 9 points. The center point, and the 4 extreme diagonal points - none of the four the surround the center point would focus at all - the lens (Minolta 50mm 1.7, wide open) just kept hunting....

What's going on!?

-Matt

 

[TrojMacReady]

the plot thickens.....

So using the focus sheet some more, keeping the camera in landscape, I tried using some of the other focus points to check results - before i could, something more interesting (or troubling happened) - I can only get the focus to lock on 5 of the 9 points. The center point, and the 4 extreme diagonal points - none of the four the surround the center point would focus at all - the lens (Minolta 50mm 1.7, wide open) just kept hunting....

What's going on!?

The outer points are less sensitive and usually result in slower focusing to begin with. But when light levels are sufficiencly low, they often give up long before the center point(s). This often has to do with the type of focus point (cross vs line etc.) but even the vignetting of lenses at the wider apertures plays a role here. Because more vignetting again means less light for the outer points.

In short, try again in good light and maybe a different target with more contrast/depth for easier focusing.

 

[mmhendrie]

thanks - I'm not sure if this is just inexperience coupled with frustration at not getting sharp shots more consistently.

I seem to sit down and just practice in my living room, with static objects, just focusing and shooting, and sometimes its sharp, and sometimes its soft...and i can't figure out why its sometimes soft.

-Matt