Jump to content

A7RII focuses better using AF-C than AF-S?


Recommended Posts

Hi all,

 

New member here, just recently purchased my first mirrorless camera (A7RII), switched from Canon dSLR.

 

I still have to perform additional tests, but I am noticing that I consistently get sharper images when using AF-C mode instead of AF-S. I'm not 100% sure yet, but it looks like my A7RII is front focusing when in AF-S mode.

 

I shot some test images with the camera mounted on a tripod with a stationary target, and for some reason pictures taken in AF-C mode generally appear sharper.

 

I am using a Batis 85mm lens right now, but also noticed this with a FE 85 1.8. Steadyshot was turned off. Shutter speed was 1/125, ISO 100, apertures ranging between 1.8 and 5.6.

 

Has anyone noticed similar behavior? I would expect that switching between these two focus modes shouldn't have any effect on camera's focusing ability in this particular scenario.

 

Thank you in advance for your help!

 

Regards,

Russ

Link to post
Share on other sites

Hi all,

 

New member here, just recently purchased my first mirrorless camera (A7RII), switched from Canon dSLR.

 

I still have to perform additional tests, but I am noticing that I consistently get sharper images when using AF-C mode instead of AF-S. I'm not 100% sure yet, but it looks like my A7RII is front focusing when in AF-S mode.

 

I shot some test images with the camera mounted on a tripod with a stationary target, and for some reason pictures taken in AF-C mode generally appear sharper.

 

I am using a Batis 85mm lens right now, but also noticed this with a FE 85 1.8. Steadyshot was turned off. Shutter speed was 1/125, ISO 100, apertures ranging between 1.8 and 5.6.

 

Has anyone noticed similar behavior? I would expect that switching between these two focus modes shouldn't have any effect on camera's focusing ability in this particular scenario.

 

Thank you in advance for your help!

 

Regards,

Russ

Just a thought if you have Pre-AF on try turning it off. It seems to cause more problems than it solves.

I'm invariably in single shot mode including with my Batis 85 and don't have the problem you have.

Link to post
Share on other sites

Thanks for your comments.

 

I do have pre-AF OFF so that's not the issue - I wish it was that easy. Good to know you're having success with AF-S, jayteepix. Have you ever tried comparing AF-S and AF-C while shooting the same, static subject to see if you notice any considerable differences in terms of image sharpness between the two modes?

 

Cheers,

Russ

Link to post
Share on other sites

Thanks for your comments.

 

I do have pre-AF OFF so that's not the issue - I wish it was that easy. Good to know you're having success with AF-S, jayteepix. Have you ever tried comparing AF-S and AF-C while shooting the same, static subject to see if you notice any considerable differences in terms of image sharpness between the two modes?

 

Cheers,

Russ

Russ

I haven't done any static / tripod tests sorry.

I did pop out to the garden today and shot some flowers in both AF-S and AF-C hand held with hardly (if) any breeze and no difference having had a quick look. The problem is I can't see anything in the exif that tells me which was which mode [that's in Capture One].

I almost always use BBF to focus and then reframe. and I have OSS on my A7R2 body always [even on a tripod as I forget but it doesn't see to matter] and I have two lenses that have IS as well.

I'm wondering if AF-C is anticipating movement somehow but I have no idea but assume one reason for using that mode would be for tracking [even mounted on a tripod).

Jamie

Link to post
Share on other sites

Russ

I haven't done any static / tripod tests sorry.

I did pop out to the garden today and shot some flowers in both AF-S and AF-C hand held with hardly (if) any breeze and no difference having had a quick look. The problem is I can't see anything in the exif that tells me which was which mode [that's in Capture One].

I almost always use BBF to focus and then reframe. and I have OSS on my A7R2 body always [even on a tripod as I forget but it doesn't see to matter] and I have two lenses that have IS as well.

I'm wondering if AF-C is anticipating movement somehow but I have no idea but assume one reason for using that mode would be for tracking [even mounted on a tripod).

Jamie

 

 

Jamie,

 

Thanks so much for your reply! I think the fact that you have a hard time telling apart images taken in AF-S and AF-C shows that these two modes CAN produce images of equal or at least similar sharpness. I appreciate you taking the time to do this test!

 

Best,

Russ

Link to post
Share on other sites

`    

    

 

I've noticed that AF-S has a tendency to lock on and not 

"double check" its own result. AF-C OTOH is never 100% 

finished with focusing so it does double check itself, seen 

by the user as more final small focus tweaks after it finds  

its initial focus. This could be the effect you're observing.

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...