Harry's GPS Suite Forum

Hi Harry,

Just had my first ever track day, it was beyond awesome! I'm having trouble getting the OBD data to line up with the video. I have set the "Overlay Synchronization" to 0, helped a bit but the delay is still pretty noticeable. I am using an Android if that matters.

Anyways here is the sample video: https://www.youtube.com/watch?v=0ZmDwe8nNiI

Thanks!

Great video!

Looking into the video it seem both OBD and acceleration are ahead of the video? This means you need to *increase* Overlay Synchronization. Beyond data / video adjustments, it is possible to adjust the individual sensors (effective next time you record something). I do not see this is really necessary for your recordings, just wanted to clarify on the option. There are several discussions on this topic here on the forum, search for "sensor delay".

- Harry

Thanks for the Reply Harry,

I tried increasing the Overlay Synchronization to 2 and it is much worse! I believe I need a negative number for the overlay but I don't believe this is possible. Anything I can do after the fact to trick the software or something?

Thanks

Dan

Yes, I'm sure, changing it from 0 to 2 seconds is a far too big jump. I'd try 0.5 instead of 0 (standard is 1.0). In case sync is not precise, changing it by +-0.5 seconds is usually the solution. The delay is the time from "reality" to arrival in the phone. So a negative delay makes no sense. As written above, with OBD slightly ahead of video, you need to increase the video delay (from 0).

- Harry

dew1989,

What are you using for a mount? The jello effect from vibration in your video is really bad. You didn't let YouTube 'fix' your video did you? I've never found that to help.

The other thing you might do is mount your camera so it can see the dashboard, or at least the tachometer. That would give you a better estimate of the delay. You don't have to drive on a race track to do this.

Harry: I'm working on finding the optimal time, so far .9 seems to be pretty good. Thanks for your help!

gplracerx it's a suction RAM mount. there are no stabilizations on youtube or in the lap timer.

it's a suction RAM mount. there are no stabilizations on youtube or in the lap timer.

In my opinion the single suction cup mount is too flexible. I've been experimenting with the triple cup mount (RAM Triple Suction Base with B-Ball RAP-B-365-224-1U), which is much firmer as the direction of flex in the individual cups are at 120 degrees from each other. But I've been having problems with my car so I don't have anything definitive yet. It does take up a lot of space on the windshield, but the other option is gluing a disk to the windshield more or less permanently.

The vibration looks to be mostly up and down. You could try orienting the mount so the diamond is vertical and see if that makes a difference.

Good idea, I'll try that next time! I don't think I would want any less visibility than the mount already gives me.

gplracerx wrote:In my opinion the single suction cup mount is too flexible. I've been experimenting with the triple cup mount (RAM Triple Suction Base with B-Ball RAP-B-365-224-1U), which is much firmer as the direction of flex in the individual cups are at 120 degrees from each other. But I've been having problems with my car so I don't have anything definitive yet. It does take up a lot of space on the windshield, but the other option is gluing a disk to the windshield more or less permanently.

The vibration looks to be mostly up and down. You could try orienting the mount so the diamond is vertical and see if that makes a difference.

I just ordered both the triple suction cup (aluminum) as well as a two cup variant (RAP-333-224-1U, composite) for testing (and report my experience). Pretty amazing the cups are the same size like the standard recommended mount (RAM-B-166U) - these parts get huge... Looking into the overall portfolio RAM Mount offers, it seems it is open to go bigger and bigger... At some time it becomes a question of space available / stability added...

For the standard recommended mount (RAM-B-166U) - I used for almost all videos posted in youtube - I indeed use a vertical orientation for the arm. This means the cup is attached directly below the mirror - in the upper part of the windscreen. The arm is going down and the phone itself it at approximately 30% of the windscreen height. This effectively reduces vertical vibrations and makes it easy to get the suction cup out of the cam's field of view.

@gplracerx, do you know already if it is possible to mount the phone in a way the triple base is not getting into the cam's FoV?

- Harry

Harry,

It's going to depend on how much your windshield is tilted. In my Mustang, the windshield is at a fairly low angle. I'm using the shortest arm and the mount can be seen in the upper right corner of the video. I could use a longer arm, but since there's still flex in the balls, I might get more vibration with a longer arm. It's still a work in progress. I mount it near the rear view mirror and most of the mount is behind the mirror from the driver's perspective. It looks bigger from outside the car than it does from the driver's point of view.

I think the accelerometer data looks better too.