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Soft Focus on A7II with FE-55 1.8 with AF-C


Kami_sn
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I have an issue with my A7II and Sony/Zeiss 55 1.8 when I tried to shoot sport action shots this weekend from my son while playing tennis, I used AF-C with wide zone, majority of the time the little green squares were shown on the face meaning the face was in focus and I was shooting in good amount of overcast outdoor light at shutter speed of 1600 and 2.8F and 100 ISOS but almost all the shots came out soft and it seemed the camera was focusing a little bit more front focusing since the shirt looked more focused.  However I have done portraits before (AF-S and Center S focus) with the same lens and images came out very sharp with off camera flash and umbrella setups (indoor).

After action shots yesterday I tried still shots and DMF option and seemed I could do better focus tuning adjustments with magnification assist option that indicates that my unit may have problem lock the focus correctly and then I thought like any other pro DSLR that I owned before I could do some micro AF adjustments, but it seems the A7II only supports Micro AF for A mount lenses with adapter which is very weird for a camera this advance and at this price range.

I am wondering if there is something that I am not doing correctly?!  I am also not so sure if this issue is coming from lens or body since I have only this one lens at this time as I sold my Canon and the lenses and am building up my Sony gear.

On the other hand I have latest firmware on the body but I am not sure if I have the latest on the lens which I will be checking it tonight but I don’t think the new lens firmware had anything to do with auto focus.

Thanks for your help.

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You could try a combination of AF-C, Face Detect, and some variation of Lock-on Focus (perhaps not necessary, but sometimes interesting). Or even just AF-S with Face-Detect.

 

Also, you could try your current settings against a stationary object/person to see if the camera has a preference for a face or the shirt (which is a little closer). I assume you were not using face detect. 

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it occurs to me that f2.8 gives a very shallow dof and a 50 mm is a lens not ideal for sport unless you are on  top of the subject, which since it was tennis I guess you were not. I wonder if the green square were being a bit over enthusiastic in their suggestions, you might have done better with afc and centre .

 

theoretically you don't need to adjust as the camera is mirror less,

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I usually use AF center and do hold focus and recompose and shoot which gives very good results and to be honest I don't do too many sports so I don't have a good baseline to compare against, however I agree that the lens may not be a good option for sports due to shallow depth of field and distance to the subject I needed to have (I basically was standing on the side lines). I used AF-C due to action and I did not have face detection nor tracking lock active.

 

So there is no need for micro AF adjustment for any of mirrorless cameras?

 

In the past I had issues with image stabilizer causing blur or soft pictures, do you think this could be a contributor too?

 

I will try again and see if I can get better shots!

 

 

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Plenty of lack of understanding of hardware is evident

here. F/2.8 for rapid action AF ? It's unrealistic. Micro

Adjusting AF on a live view camera ? Skooz me but it's

live view which we deploy to check the accuracy of any

mirror dependent AF system.

 

Nice of the forumites responding above to offer some

trial solutions but you should read up on photographic

principles and also how hardware is designed to do its

best enable us to conveniently apply those principles.

 

The hardware can only "do its best" but cannot perform

magic. A better grasp of basic principles would clarify for

you which circumstances most greatly push the limits of

the hardware vs which circumstances put the hardware in

its "comfort zone". These differences are the same for

robotic modern hardware as for a human user of simple

ancient manual hardware. Altho the modern hardware is

faster and more accurate, it still faces exactly the same

challenges as a human operating slower, older hardware.

 

The complaints in the OP fly in the face of reasonable

expectations, given the way photography works.

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Plenty of lack of understanding of hardware is evident

here. F/2.8 for rapid action AF ? It's unrealistic. Micro

Adjusting AF on a live view camera ? Skooz me but it's

live view which we deploy to check the accuracy of any

mirror dependent AF system.

 

Nice of the forumites responding above to offer some

trial solutions but you should read up on photographic

principles and also how hardware is designed to do its

best enable us to conveniently apply those principles.

 

The hardware can only "do its best" but cannot perform

magic. A better grasp of basic principles would clarify for

you which circumstances most greatly push the limits of

the hardware vs which circumstances put the hardware

in its "comfort zone". These differences are the same for

robotic modern hardware as for a human user of simple

ancient manual hardware. Altho the modern hardware is

faster and more accurate, it still faces exactly the same

challenges as a human operating slower, older hardware.

 

The complaints in the OP fly in the face of reasonable

expectations, given the way photography works.

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I would ask, how much your son was moving around, towards and from the camera - or was he fairly static. I ask because I'll make the assumption that you were standing just off court, approx 5 m away. Shooting a 55mm lens at f2.8 on a FF sensor, you'd have a DOF off approx 1.4m, of which 60cm would be closer to the camera and 80cm further away.

 

If he was running all over the court, then the afc could struggle.

 

At 55mm at this distance you are hardly getting separation of the subject from the background anyway at f2.8. Why insist on such a wide aperture with a small sharp DOF? Why not just go for a smaller aperture to make sure you get him in focus? If you were using a 200mm lens, then sure go for a totally OOF background at a wide aperture, but be aware your keeper rate would go down.

 

Stop down the aperture, keep the shutter speed 1/1000 and bump the iso. Also remember the A7's are not sports cameras, however, they can work if you expect not to have 100% keepers.

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I would ask, how much your son was moving around, towards and from the camera - or was he fairly static. I ask because I'll make the assumption that you were standing just off court, approx 5 m away. Shooting a 55mm lens at f2.8 on a FF sensor, you'd have a DOF off approx 1.4m, of which 60cm would be closer to the camera and 80cm further away.

 

If he was running all over the court, then the afc could struggle.

 

At 55mm at this distance you are hardly getting separation of the subject from the background anyway at f2.8. Why insist on such a wide aperture with a small sharp DOF? Why not just go for a smaller aperture to make sure you get him in focus? If you were using a 200mm lens, then sure go for a totally OOF background at a wide aperture, but be aware your keeper rate would go down.

 

Stop down the aperture, keep the shutter speed 1/1000 and bump the iso. Also remember the A7's are not sports cameras, however, they can work if you expect not to have 100% keepers.

I would say he was active enough to make the focusing challenging, I agree that F stop may have been too open for the situation but I was trying to get some separation in the photo, however as you mentioned I was not able to do so. I guess my other question is if the camera struggles to keep up at 2.8 and 55 focal length to lock the proper focus then as you mentioned it would be even worst at 200 and f4 lets say with a G lens.

 

I guess at five meter distance and 55 focal length maybe f8 or 11 should be used? That gives me enough depth of field approximately 1.5 meter in front of the subject to rule out out of focus due to the DOF and concentrate on nailing the focus.

 

 

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You are right that a 200 at a wide aperture would make this even harder...... nature of the beast with Sony A7's. That's why at football matches the pros are all using Canon 1Dx/Nikon etc with their big lenses. But, for the regular Joe up the park with their kids, this often is not ideal. (having just sold my 1Dsii and 70-200 for Sony setup!)

 

A smaller aperture like f8+ gives you a bigger DOF which will help the number of keepers. Experiment. Also practice messing around with focussing. To get pictures of my kids on the swings at the park, instead of letting autofocus hunt like buggery back and forward, I just set manual focus on where the kids would be at the top of their swing, then just shoot when they hit that point. Nails it every time. Perhaps you could do something like that if you want to shoot wide open or use longer focal length lenses wide open with shallow DOF

 

On looking at your 2 sample pics again, they don't look particularly OOF to me. You said they were unedited jpgs from the RAW files. Maybe it's the forum compression, maybe my eyes, but if you worked on them a bit, a bit of sharpness, clarity , contrast, you'd get more of a pop you were expecting.....

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Guest Peter Kelly

As others have mentioned, the main issue is likely because you're pushing the system and any camera will struggle doing so. Indeed, it's part of what you admit by saying you don't often shoot sports and that is a very particular discipline which takes quite a lot of practice to master.

 

So the cons are: too short focal length, too wide an aperture, not the ideal focus setting, not the ideal exposure settings, not the best sports camera, and that shirt!

 

To answer them, it would be better to use a longer lens, but if you don't have one there's nothing you can do but perservere!

 

In this case, I don't actually think the aperture is necessarily too much of an issue, because 1.4m is still sufficient. However, with the lack of strong subject separation, going a little narrower will help.

 

The focus mode is one of experience. I don't think I'd use 'Wide' here, but prefer 'Expand lock-on' if I was using continuous. That said, if your subject is moving fast then often the best idea is to use manual focus and take shots when your subject is at a certain distance. Unfortunately, tennis is not an ideal sport for that! The best thing is for you to try different settings yourself and find the one that works best for you.

 

As to exposure settings, I personally would not use ISO100 unless in the very brightest of conditions. You won't be gaining much at all in terms of quality, but you'll lose a boatload of shutter speed.

Better to go at ISO 800 and 1/8000 than ISO 100 and 1/1000, unless you want to introduce some motion blur.

 

When it comes to your camera, you just have to work with what you have and the A7ii is not really so bad. Not the one you'd use if you wanted to make your living, but perfectly good nontheless.

 

To agree with another point, with your son wearing such a bright shirt it's almost certain to have affected the AF, especially using the 'wide' mode. Of course, if that's your son's favourite... ;)

 

All that said, the pictures don't appear to be as far out as your post suggests. A little processing and careful sharpening and I don't see much of a problem.

We can't all be the greatest photographers on Earth, so quite why your request received such aggressive criticism I have no idea, but I apologise on their behalf.

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As others have mentioned, the main issue is likely because you're pushing the system and any camera will struggle doing so. Indeed, it's part of what you admit by saying you don't often shoot sports and that is a very particular discipline which takes quite a lot of practice to master.

 

So the cons are: too short focal length, too wide an aperture, not the ideal focus setting, not the ideal exposure settings, not the best sports camera, and that shirt!

 

To answer them, it would be better to use a longer lens, but if you don't have one there's nothing you can do but perservere!

 

In this case, I don't actually think the aperture is necessarily too much of an issue, because 1.4m is still sufficient. However, with the lack of strong subject separation, going a little narrower will help.

 

The focus mode is one of experience. I don't think I'd use 'Wide' here, but prefer 'Expand lock-on' if I was using continuous. That said, if your subject is moving fast then often the best idea is to use manual focus and take shots when your subject is at a certain distance. Unfortunately, tennis is not an ideal sport for that! The best thing is for you to try different settings yourself and find the one that works best for you.

 

As to exposure settings, I personally would not use ISO100 unless in the very brightest of conditions. You won't be gaining much at all in terms of quality, but you'll lose a boatload of shutter speed.

Better to go at ISO 800 and 1/8000 than ISO 100 and 1/1000, unless you want to introduce some motion blur.

 

When it comes to your camera, you just have to work with what you have and the A7ii is not really so bad. Not the one you'd use if you wanted to make your living, but perfectly good nontheless.

 

To agree with another point, with your son wearing such a bright shirt it's almost certain to have affected the AF, especially using the 'wide' mode. Of course, if that's your son's favourite... ;)

 

All that said, the pictures don't appear to be as far out as your post suggests. A little processing and careful sharpening and I don't see much of a problem.

We can't all be the greatest photographers on Earth, so quite why your request received such aggressive criticism I have no idea, but I apologise on their behalf.

Thank you Peter for such a detailed and constructive post, you mentioned some valid points that will help me to improve my photography. In addition to my limited knowledge of photography there were two other contributors which one was new camera which still I am learning how to use it and second the kind of photography which in this case was action/sports. Once you add up all the factors together I was not expected to do anything better than I could accomplish on these shots.

 

The point is people like me post questions here to improve their photography and get some constructive comments like yours and some previous ones who spend time and effort to raise the bar for the community and that is great value, however there is always posts that won't add any value to the discussion and aimed to steer the conversation which is OK and my experience shows ignoring them is the best solution.

 

Thanks again for your input and I will try to implement them in my next opportunity.

 

Cheers.

 

 

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I've been shooting a lot of sports lately with my a7II. I haven't tried my 55 much, but use a sigma 70200 primarily. Just as a tip/trick I've learned, shoot from a lower vantage point. This will eliminate the ground from throwing off your focus, especially in phase detect. Chances are the background would also produce more contrast as well. At least then, you will either nail the focus or see that it was way off to infinity, not a lot of in between. Just my two cents, but it works well shooting in dark gyms for wrestling and basketball when I'm struggling along shooting 1/500 at 2.8 with ISO's around 5000. Just keep practicing!

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I'm new to the A7II as well and my only lens is the 55 1.8.  

 

I'm no expert and my eyes are old but the two photos you posted are good!  My sense is, with software and practice,  any photo can be made better.  

 

I just sent a few days with my three grandsons (9, 5, 3) and had a blast with my new gear.  Could I had done better, YES!  When I look at the photos I will remember the fun not the quality of the photo.  Just my two cents!

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