G9 + 100-400mm lens: Autofocus Locks on Background

[Ajay1]

I've had the combination of the G9 and 100-400 lens for over a year now. Currently at the latest firmware update as far as I know (v 1.2). I still run into a problem when photographing birds at close range...If the G9 grabs focus on the background, it is nearly impossible to refocus on the foreground bird. The only thing I can do at this point is point the camera at another nearby object that nearly fills up the framed image, then it will refocus on the foreground and I can then focus on the foreground bird -- if it's still there.

I have tried every focus point setting known to this camera. I have tried every autofocus setting known to man. No matter what setting, if you lose close focus and it grabs the background, good luck in re-establishing foreground focus on subjects that fill up about 40% of the frame or less.

The strange thing is, is that the G9 appears to recognize that a foreground object exists, but never switches focus. I use back button focus and keep pumping it, hoping it will grab the foreground subject.

It's always been a frustration with this camera and the 100-400mm lens. (I wish the lens had a close focus switch so that it would prevent the lens from trying to focus to infinity.)

I'm curious to know if others have this same problem and if there is any setting I am missing (although I think I have tried everything).

Because of this problem I primarily use this camera and lens for wildlife video work only.

 

[Brownie]

Poke around here in the Panasonic forum and look for the birding threads. Tons of discussion on background focusing, etc. There are some guys on here that are very successful with the G9 in the same circumstances.

 

[Brownie]

G9 for Birding

Think I have sorted the G9 BIF settings

Here are two of them.

 

[Ajay1]

I'm not talking about BIF settings. I am talking about initial focus of close subjects. They do not need to be in-flight.

For example, a bird perched on a thin, metal fence post 30' away. Behind the fence post, there is a tree line. The camera is focused on the trees. Attempting to refocus on the bird or the thin metal fence post in the foreground is a lesson in futility. The only way to get close focus is to focus on the base of the fence post in which the ground fills the frame, then pan up and hopefully the bird is still there.

BTW, the focal planes of the bird in foreground and trees in background are very far apart. In other words, when the bird is in focus, the background is completely blurred with no definition.

Here's an example:

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[Pluttis]

I dont own a Pansonic camera, but cant you set it up with AF+MF so MF overrides AF-S/AF-C? , if possible it would let you quickly adjust focus manually while you still hold the shutter half pressed.

 

[Jrsforums]

Have you tried ‘one area’, with the box reduced to mostly just include the bird?

 

[Bidkev]

I had a similar problem with this lens and the olly 5 mk ll. Many times it just refused to focus and simply hunted, mainly in low light with low contrast. I get the best out of it by locking the small square permanently in centre and focusing, for example in your pic above, with the square overlapping the highest contrast area of the subject such as the dark wing and the pale chest, if the eye and head colour doesn't work. I then recompose with shutter half pressed. The forgiving nature of m43 DOF seems to help with the move of POF

 

[D7k1]

I have seen that behavior and I use either manual focus or switching focusing distance switch on lens, takes less than a second and you don't move off target. Doesn't happen that often on mine. Also happens on my Gx8, and I do the same thing to fix it.

 

[Ajay1]

Have you tried ‘one area’, with the box reduced to mostly just include the bird?

Yes. I actually reduced the size of the one focus point as small as I could make it and it had no effect. Even though the one, small focal point clearly was only on the bird, it would never focus on the foreground bird. Good idea and one that I thought would work.

 

[Ajay1]

I dont own a Pansonic camera, but cant you set it up with AF+MF so MF overrides AF-S/AF-C? , if possible it would let you quickly adjust focus manually while you still hold the shutter half pressed.

I tried MF + AF as well as AF-S and it make no difference. It still cannot pick out the foreground subject. Thanks.

 

[Ajay1]

I have seen that behavior and I use either manual focus or switching focusing distance switch on lens, takes less than a second and you don't move off target. Doesn't happen that often on mine. Also happens on my Gx8, and I do the same thing to fix it.

Thanks. Using manual focus is a work-around of sorts and does work as long as I have time to get it close to the foreground bird before it takes off. Still a bit time consuming however. Once the lens has gained near-focus, it does lock-on and hold focus. It's the initial focus that is the problem.

 

[Pluttis]

Thanks. Using manual focus is a work-around of sorts and does work as long as I have time to get it close to the foreground bird before it takes off. Still a bit time consuming however. Once the lens has gained near-focus, it does lock-on and hold focus. It's the initial focus that is the problem.

This is what i meant when i said "AF+MF so MF overrides AF-S/AF-C , if possible it would let you quickly adjust focus manually while you still hold the shutter half pressed"

 

[masayoshi]

AF+MF adjustment works when the initial lock is close. But in OP's case, where AF lock goes to background (infinity), it takes very long turn of the focus ring before getting close to the target. I think what's going on here is due to the distance between the target and the background. If the distance is to long, DFD may take very long time to find out good contrast in the target area/box.

As a remedy, does G9 have Preset MF override, so that it resets the FL to something like 10-20m, and restart AF from there? I used to own G9 but sold recently, and can't remember.

 

[Pluttis]

AF+MF adjustment works when the initial lock is close. But in OP's case, where AF lock goes to background (infinity), it takes very long turn of the focus ring before getting close to the target. I think what's going on here is due to the distance between the target and the background. If the distance is to long, DFD may take very long time to find out good contrast in the target area/box.

As a remedy, does G9 have Preset MF override, so that it resets the FL to something like 10-20m, and restart AF from there? I used to own G9 but sold recently, and can't remember.

Thats true, it will require long turn/time but i think its either that or with AF refocus on the foreground and then pan up and focus on the bird

 

[Stanga]

This focusing issue is not limited to the 100-400mm. It's possible on other lenses as well. I get it on the 14-140mm MKII, but less so on the 45-175mm.

 

[Pluttis]

LUMIX Auto Focus Workaround

 

[Ajay1]

I just saw something here that leads me to believe this is a contrast-detect problem and has nothing to do with the 100-400mm lens nor the G9. I was watching a video from Kai W reviewing the Panasonic S1. In his video at the 6:24 mark, he describes almost the exact same problem using the S1. Just as I have seen, the camera seems to recognize there is a foreground subject, but stays stuck on a busy background. It now has me wondering if this is a limitation of contrast-detect autofocus? Or they need to fix their firmware? Even on the S1.

Here is the video. Go to the 6:23 mark.

FYI, I am not trying to pick on Panasonic. I love their cameras but this problem does have me frustrated. Thanks to everyone for their feedback.

 

[kinlau]

I also have the same problem with the G9 and 100-400, and my workaround is to just do a quick point at the ground and shoot, and then acquire my target.

Something that occasionally works, especially if I can’t shoot the ground (eg snow covered ground is just as bad), is to flick the AF joystick and the double pump or long press (1 sec or more) the shutter. That seems at times to cause the AF to try harder.

 

[D7k1]

Think it is just something we have to live with, but I do agree it can be frustrating at times. Since I shoot mostly BIF against sky or water not a deal breaker for me.

 

[Phocal]

I'm not talking about BIF settings. I am talking about initial focus of close subjects. They do not need to be in-flight.

For example, a bird perched on a thin, metal fence post 30' away. Behind the fence post, there is a tree line. The camera is focused on the trees. Attempting to refocus on the bird or the thin metal fence post in the foreground is a lesson in futility. The only way to get close focus is to focus on the base of the fence post in which the ground fills the frame, then pan up and hopefully the bird is still there.

BTW, the focal planes of the bird in foreground and trees in background are very far apart. In other words, when the bird is in focus, the background is completely blurred with no definition.

Here's an example:
View attachment 746287

How much crop is on this photo?