Focus problem - is this a fault in the G7 camera

What I'm trying to find out is if I have a fault on my G7 camera or does this normally happen with the G7 camera.

When video recording the focus will change for a moment and what I'm recording goes out of focus. There doesn't seem a reason why the camera should attempt to refocus after it has correctly focused on a subject. There is nothing that becomes near the camera for the change in focus to happen. It can happen once within a 5 minute video clip and goes out of focus for a few seconds. It's enough ruin an important moment.

The camera is set to AFS/AFF

What I need to know is do owners of the G7 camera also have this problem?

If needed I could upload a video clip example.

Brian

Brisn5757 wrote:

What I'm trying to find out is if I have a fault on my G7 camera or does this normally happen with the G7 camera.

When video recording the focus will change for a moment and what I'm recording goes out of focus. There doesn't seem a reason why the camera should attempt to refocus after it has correctly focused on a subject. There is nothing that becomes near the camera for the change in focus to happen. It can happen once within a 5 minute video clip and goes out of focus for a few seconds. It's enough ruin an important moment.

The camera is set to AFS/AFF

What I need to know is do owners of the G7 camera also have this problem?

If needed I could upload a video clip example.

Brian

So I'm still new to video with my g7, but I use AFC tracking with good results

set the camera to aF then get your focus then set camera to MF and you will have the focus not changing if you leave your lens alone.

it may not solve every situation, but will solve some.

I used to have a G7.  In interior  (relatively dim) light the G7 can lose focus and refuse to refocus for a significant time.  I have examples in movies.

But now I have a G9 and especially with 1.2 Firmware the focusing is much better, and it's ADJUSTABLE in camera, which is awesome.

Adjust the focus area to suitable size, or set up custom focus points for AF (custom multi AF mode).

I usually have Continuous AF set to OFF when I am filming (this is adjusted from the video menu). With this option, the camera auto-focuses only when I half-press the shutter.

pannumon wrote:

Adjust the focus area to suitable size, or set up custom focus points for AF (custom multi AF mode).

I usually have Continuous AF set to OFF when I am filming (this is adjusted from the video menu). With this option, the camera auto-focuses only when I half-press the shutter.

To understand you better, do you mean that while video recording you half press the shutter to correct the focus if you move from a far object to a near object?

Brian

burritosandbeer wrote:

Brisn5757 wrote:

What I'm trying to find out is if I have a fault on my G7 camera or does this normally happen with the G7 camera.

When video recording the focus will change for a moment and what I'm recording goes out of focus. There doesn't seem a reason why the camera should attempt to refocus after it has correctly focused on a subject. There is nothing that becomes near the camera for the change in focus to happen. It can happen once within a 5 minute video clip and goes out of focus for a few seconds. It's enough ruin an important moment.

The camera is set to AFS/AFF

What I need to know is do owners of the G7 camera also have this problem?

If needed I could upload a video clip example.

Brian

So I'm still new to video with my g7, but I use AFC tracking with good results

I think it uses more battery power but might be worth a try.

Brian

JosephScha wrote:

I used to have a G7. In interior (relatively dim) light the G7 can lose focus and refuse to refocus for a significant time. I have examples in movies.

But now I have a G9 and especially with 1.2 Firmware the focusing is much better, and it's ADJUSTABLE in camera, which is awesome.

From the way I read it, your G9 had a problem focusing but this has improved with the firmware update.

I can understand having problems focusing in dim light but the refocusing happens in bright lighting conditions.

Brian

Tim Reidy Productions wrote:

set the camera to aF then get your focus then set camera to MF and you will have the focus not changing if you leave your lens alone.

it may not solve every situation, but will solve some.

The only problem with this idea is that when video recording the subject is often changing it's distance from the camera. For example if I'm recording a parade then the float in the parade is a distance then gets very close to the camera when it passes by the camera and then distance as it goes further away.

However if the camera does start to chance focus on fixed distance objects then I quickly switch to manual focus once it has correcly focused again

Brian

Brisn5757 wrote:

Tim Reidy Productions wrote:

set the camera to aF then get your focus then set camera to MF and you will have the focus not changing if you leave your lens alone.

it may not solve every situation, but will solve some.

The only problem with this idea is that when video recording the subject is often changing it's distance from the camera. For example if I'm recording a parade then the float in the parade is a distance then gets very close to the camera when it passes by the camera and then distance as it goes further away.

it may not solve every situation, but will solve some. my technique was not a good idea for some parades, but could be good if you gave the parade a lot of focus distance if shooting far enough away.

Brisn5757 wrote:

pannumon wrote:

Adjust the focus area to suitable size, or set up custom focus points for AF (custom multi AF mode).

I usually have Continuous AF set to OFF when I am filming (this is adjusted from the video menu). With this option, the camera auto-focuses only when I half-press the shutter.

To understand you better, do you mean that while video recording you half press the shutter to correct the focus if you move from a far object to a near object?

Brian

I have a GX85, but I do the same thing. I half press the button to refocus during recording.

With Continuous AF off, the camera never refocuses on its own while recording, only when I want it to.

JakeJY wrote:

Brisn5757 wrote:

pannumon wrote:

Adjust the focus area to suitable size, or set up custom focus points for AF (custom multi AF mode).

I usually have Continuous AF set to OFF when I am filming (this is adjusted from the video menu). With this option, the camera auto-focuses only when I half-press the shutter.

To understand you better, do you mean that while video recording you half press the shutter to correct the focus if you move from a far object to a near object?

Brian

I have a GX85, but I do the same thing. I half press the button to refocus during recording.

With Continuous AF off, the camera never refocuses on its own while recording, only when I want it to.

As you need to use this method to refocus then do you find that your camera goes out of focus for a moment for no reason.

What I'm trying to determine is do I have a fault on my G7 camera. If so I'll need to get it repaired before the warrant expires.

Brian

Brisn5757 wrote:

As you need to use this method to refocus then do you find that your camera goes out of focus for a moment for no reason.

With 'Continuous AF' OFF, the camera makes initial focus when you start the video. After that the focus is locked at that distance. The camera does not change the focus. It is kind of manual focus mode. However, if the subject moves closer/forward to the camera, it is necessary to adjust the focus distance accordingly. With this method, the camera operator chooses when this happens by half-pressing the shutter release button. Using high F-numbers (like F8) helps with this.

What I'm trying to determine is do I have a fault on my G7 camera. If so I'll need to get it repaired before the warrant expires.

I am quite sure your camera is OK. Video AF in this camera is not perfect. In different scenarios, different methods work the best. It can take some practice to know how to always get adequate results. In 1080 mode, the AF might be better than in 4k (at least it should be more responsive).

Brisn5757 wrote:

pannumon wrote:

Adjust the focus area to suitable size, or set up custom focus points for AF (custom multi AF mode).

I usually have Continuous AF set to OFF when I am filming (this is adjusted from the video menu). With this option, the camera auto-focuses only when I half-press the shutter.

To understand you better, do you mean that while video recording you half press the shutter to correct the focus if you move from a far object to a near object?

For example in that situation, yes. Or if the subject moves closer/further.

Brisn5757 wrote:

JakeJY wrote:

Brisn5757 wrote:

pannumon wrote:

Adjust the focus area to suitable size, or set up custom focus points for AF (custom multi AF mode).

I usually have Continuous AF set to OFF when I am filming (this is adjusted from the video menu). With this option, the camera auto-focuses only when I half-press the shutter.

To understand you better, do you mean that while video recording you half press the shutter to correct the focus if you move from a far object to a near object?

Brian

I have a GX85, but I do the same thing. I half press the button to refocus during recording.

With Continuous AF off, the camera never refocuses on its own while recording, only when I want it to.

As you need to use this method to refocus then do you find that your camera goes out of focus for a moment for no reason.

I haven't yet, but I use this method to make sure it doesn't happen for focus critical recordings. I have heard hunting like this can happen with Panasonic cameras. The last time I used continuous AF, I was using my GX85 and 12-32mm f/3.5-5.6 at f/5.6. It gives a decent DOF for the distance my subjects were at.

I don't know how true it is, but I have read that your initial focus immediately before you press record sets a baseline for focus, so it is best to set it to the correct focus first even if you use Continuous AF.

What I'm trying to determine is do I have a fault on my G7 camera. If so I'll need to get it repaired before the warrant expires.

Brian

I f the video is important to you Always` use M/Focus, i never use Auto-Focus even on my GH5, no Auto-Focus system is immune to the `hunting-Bug` even Phase-Detect!!

I have still to install that new firmware in to my GH5, JS, others, like yourself state that it makes one heck of a difference to their focusing systems, is it really that good?

No, i think that this is an inherent problem with most Panasonic and Olympus cameras that use contrast-detect focusing systems, phase-detect systems are better, but not infallible to odd hunting now and again, in my opinion auto-focus can not be totally trusted on most cameras, no matter what system is used, that`s why i always use manual focus!!      

Allan.

pannumon wrote:

Brisn5757 wrote:

As you need to use this method to refocus then do you find that your camera goes out of focus for a moment for no reason.

With 'Continuous AF' OFF, the camera makes initial focus when you start the video. After that the focus is locked at that distance. The camera does not change the focus. It is kind of manual focus mode. However, if the subject moves closer/forward to the camera, it is necessary to adjust the focus distance accordingly. With this method, the camera operator chooses when this happens by half-pressing the shutter release button. Using high F-numbers (like F8) helps with this.

What I'm trying to determine is do I have a fault on my G7 camera. If so I'll need to get it repaired before the warrant expires.

I am quite sure your camera is OK. Video AF in this camera is not perfect. In different scenarios, different methods work the best. It can take some practice to know how to always get adequate results. In 1080 mode, the AF might be better than in 4k (at least it should be more responsive).

Thanks pannumon.

I think I'll need to do some experimenting with my G7 camera and will try what you have suggested.

Brian