Sensor delays - overlay almost perfect - what else to tweak?

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GeoJoe
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Sensor delays - overlay almost perfect - what else to tweak?

Post by GeoJoe »

Hi All,

First post! I'm trying to get the overlay to sync up with the video. I've narrowed it down as close as I can get but I'm wondering if one of the more experienced users can take a look at this video and suggest a tweak.

I'm using the Carista bluetooth ODB II dongle on a Samsung GS5 while driving an Audi S4. Looks like I should have calibrated, as the g-force meter is off. Other than that it's looking pretty good!

See video and screenshot of the expert settings. Any suggestions are appreciated to get the sync as close to perfect as possible.

[youtube]http://www.youtube.com/watch?v=TS9Ye6FCws4[/youtube]

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Harry
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Re: Sensor delays - overlay almost perfect - what else to tw

Post by Harry »

The values are all pretty off compared to the defaults and are at extreme positions - which will never be correct. NB: all the values except Video are applied during recording and will have no effect for existing recordings. So please go back to the default values first to not completely screw up future recordings. In sync: it seems OBD is behind video meaning video is ahead. This is due to the video value reduced to 0 (which is always wrong because no sensor has no latency). Raise it to the default value (1) and revert / overlay the lap again. It will be better already.

On acceleration: you can calculate acceleration from GPS in case something went wrong during recording. Select the lap from Lap List, press Recalculate and select Acceleration.

Harry
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gplracerx
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Re: Sensor delays - overlay almost perfect - what else to tw

Post by gplracerx »

This is due to the video value reduced to 0 (which is always wrong because no sensor has no latency).
If I add a video manually by setting the finish line frame and use the default video delay of 1, the video is out of sync. A delay of zero works just fine.
GeoJoe
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Re: Sensor delays - overlay almost perfect - what else to tw

Post by GeoJoe »

This is a video delay of 1.5. Getting closer to perfect.

Thanks for all the tips Harry!

[youtube]http://www.youtube.com/watch?v=oLhzPgeONBY[/youtube]
gplracerx
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Re: Sensor delays - overlay almost perfect - what else to tw

Post by gplracerx »

I would say based on the distance to the Start/Finish line when the countdown timer disappears, you were closer the first time.

Do you really need to lift off the throttle that much going over the crest at turn 11?
GeoJoe
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Re: Sensor delays - overlay almost perfect - what else to tw

Post by GeoJoe »

11 is such a blind hill and the bottom drops out. With cars in front, ya never know what lines they will pick. Biggest pucker factor at Road Atlanta.
gplracerx
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Re: Sensor delays - overlay almost perfect - what else to tw

Post by gplracerx »

If you think that's bad, you should have driven the original course before they ruined it. It was a much tighter turn under the bridge with a blind apex. Turn 12 was much tighter too, but that only mattered if you could go through the bridge fast enough that 11 and 12 was a single corner.
firstars
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Re: Sensor delays - overlay almost perfect - what else to tweak?

Post by firstars »

Anyone got this adapter to work with harrys and iOS? Adding DUAL XGPS150A this week and OBD data is the last piece of the puzzle. Already have the caraista dongle so figured it woudl be worth trying.
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Harry
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Re: Sensor delays - overlay almost perfect - what else to tweak?

Post by Harry »

Off topic? Carista is not compatible.
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