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AutoFocus twitches

We've been using our new PTZOptics 20x NDI cameras for a couple of weeks. One of the things we have noticed is that when moving the camera, there's a focus "twitch" at the end of the movement. The scene will be in focus, but when the camera stops movement, the scene will subtly go out of focus, then back into focus again. The process takes maybe 1/5 of a second, but it's noticeable enough to be distracting.

The feeling I'm getting from reading the forums is that these cameras are typically used to move from preset to preset, but we're a church with a pastor that moves while speaking, and we need to manually pan to track his movements, and every time he pauses, he goes out of focus for a fraction of a second.

I'm looking for a way to stop this from happening. I have tried:

* Turning off auto-focus, but then when the pastor walks toward/away from the camera he does not remain in focus, and when zooming, sometimes the focus isn't stable.

* Locking the focus, same problem as above plus cannot change zoom without completely losing focus.

I'm looking for advice on either camera settings I may have missed or techniques to avoid this problem.

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Hi Kevin,

It sounds like you've done your homework on the subject so let's just dive into a few topics and we'll see if one is able to improve your situation.

Focus Sensitivity & Focus Zone Adjustments

If you're AF is acting too aggressive you may find the following settings useful to adjust the area of interest for the camera to focus on as well as how aggressively the camera will attempt to adjust it's focus.

These two (2) settings can be found by opening the OSD Menu of the PTZOptics camera and navigating to the "P/T/Z" section.

AF-Zone will offer the ability to select, approximately, 1/3 of the image where you'll be trying to keep the talent located as they move.

You can select between Top, Center or  Bottom as you're desired area of interest... if you're talent tends to be closer to the bottom of the image to capture scenery behind and above then you would want to try the Bottom option so that it gives priority to focusing on anything in the lower 1/3 of the image. 

This will help prevent the camera from attempting to focus on other objects that may be in the background and temporarily "steal the show."

AF-Sense will offer the ability to adjust how aggressive the camera will be when trying to decide to re-focus or not.

You can select between Low, Normal and High for the auto focus sensitivity.

If the talent is making slight movements causing the camera to re-adjust you may want to look at lowering the sensitivity to see if it can be more forgiving.

Now as some general suggestions to improve the image quality and thus assist with focus though not directly related to focus.

Now I can also recommend looking at your AWB Settings under COLOR in the OSD Menu. I would turn the AWB Sensitivity, AWB Sens, from High down to Normal, or if you like the look Low.

If you do not have constantly changing lighting conditions I would consider adjusting the White Balance Mode, WB Mode, from Auto to One-Push to limit additional auto adjustments to the image.

As you can see from these above suggestions the less "auto" we allow the camera to be the better the image quality and focus can potentially be.

Final notes on a coming experimental feature... while not yet available for beta testing we are in the midst of working on a solution that would allow you to define a specific focus range.

The goal is to allow you to instruct the camera that you only want it to focus on subjects between X meters - X meters so that you can essentially define a "focus range."

Anything outside of that range and the camera will attempt to ignore no matter how the camera is moved or zoomed.

Currently this does require the camera to have the Focus Re-Training performed so it can adjust it's curve to accommodate the new range properly.

If none of the above are able to improve your focusing issue please let us know and we'll be sure to work with you to get this new firmware to you for testing once we have most of the bugs worked out.

If possible to let us know if you found any of the above information helpful towards solving your issue we would greatly appreciate hearing from you again.

We've been having the same issue but only with the 12X camera, which is the closest to the stage. I will try the suggestions here and see if they work for us as well.

Hi Spencer,

If the above settings do not seem to help you can try to re-calibrate the camera's focus. 

We have a tool for that here. 

Let us know if you are still experiencing issues with your cameras focus.

You can submit a support ticket here.

How do I get to these settings option? I don't see them in the web interface. How else would I check it? Thanks! John

Hi Outreach Christian Church,

These options are only available via the OSD (On Screen Display) provided by the camera.

You can reach that interface by using the [MENU] button on the IR remote while viewing the SDI / HDMI / USB feed, or via Stream 1 if using IP Video.

If you do not have the ability to use the IR Remote you can also utilize the WebUI

To open the OSD use the PTZ / OSD drop down menu near the bottom of the page for P/T/Z models.

If using a ZCam simply pressing the WebUI P/T/Z [HOME] button will open or close the OSD.

Once you are into the cameras OSD you can find the above mentioned options for Auto Focus in the following locations

Open the OSD Menu of the PTZOptics camera and navigating to the "P/T/Z" section. 

If you do not see the exact features mentioned above it is possible that your PTZOptics camera requires a firmware update to gain the new features.

To update your firmware please visit the PTZOptics Firmware Finder:

Please note it will require the serial number(s) of your camera(s) to locate the proper firmware files.

If you continue to have issues or need further assistance please don't hesitate to return to the forums or reach out to our support team.

PTZOptics Support Information

Phone: 1-800-486-5276 x.1004



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We use a preset where the talent is zoomed in to waist up body shot, and located to the side of the image field, allowing room on the other side for power point overlays.  The camera is refocusing from time to time which is annoying...I have already reduced the AF - Sense to Normal.

I am wondering if the camera is re-focusing because in the center of the AF-Focus Zone is plain wall... nothing specific to focus on?

Is there a way to turn off Auto focus after the PTZ motion to preset position is completed and the camera is at a stationary position?

Hello Mike,

The Preset positions do store the focus information in addition to the Pan, Tilt, and Zoom info.

Actually with the latest firmware (for the 12X, 20X, and 30X SDI/NDI models), presets will also save internal menu options too, so you can set presets to use different exposure and color settings.

The latest firmware can be found here.

So for your situation I would suggest resaving this preset with the camera set to manual focus mode. This way you can get the focus set exactly as needed and each time you call that preset it will have the same focus value.

The camera will stay in at that manual focus position until you reposition the camera, at that point the auto focus will be triggered. 

Hi Colin,

Will the preset save settings feature work when presets selected from VMIX?

No, it won't work when using vMix's built in control.

vMix handles presets differently and does not actually use the presets that are stored on the cameras themselves.

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