New users - Questions / Advice

[ColinK]

Hello All and Harry.

i have been racing go karts for the last 6 months and found it was time to get an action camera.
Several of the chaps have GoPros or Drift HD's and there always been half an eye on using Laptimer and an Iphone for the GPS data and video overlays.

So yesterday i bit the bullet and purchased the app.
i am running an Iphone 4s 16GB.
as the karts we race are not our own it means i must mount my Iphone on my heltmet.
so i have ordered one of these Optrix XD4 iPhone Mount.

the first real test will be this weekend when i have two races.
a 40 Minuit race on Saturday, total record time will be around 60 mins in one go.
and a 60 min race on Sunday, total record time of around 80 mins in one go.

i have already set up a simple lap with 3 POI using the Google maps method and it worked a treat.

couple of question's.

as I'm in a kart and the iPhone is helmet mounted, I'm not going to have any power supply for it.
I'm also not going to be able to handle the phone when racing.
so I'm basically going to put it in the housing and tell it to start recording.
i will also set the focus lock at the same time.

after that i wont touch it again until the end of the race.

Will the battery of the Iphone 4s last as long as 80/90 mins when recording in one go ?
what video resolution is a good compromise ?

Are there any other setting i need to concern myself with ?

[Harry]

Welcome

No good message on 90 minutes: check memory first, at HD resolution this will require 7GB (check viewtopic.php?f=6&t=459), at FullHD nearly 17 GB... Both not possible using a 16 GB device. Overlaying will require additional space although this is by lap only and not that critical for a cart track. On power consumption: video is the most demanding component again. The lower the resolution, the less battery will be required. I have no exact numbers available - maybe someone else can add. I'm almost sure it will not work for FullHD, and hardly at HD. Net net, chances are low you will receive what you want at HD or FullHD. SD (i.e VGA 640x480) will work but is less enjoyable to view. My recommendation would be to use LapTimer as a lap timer only for the full distance, and record FullHD video during qualifying (is there such a thing?) or another opportunity only.

With video, you hit the limits fast...

- Harry

Btw, GoPro HERO will not work either without an external power supply / battery pack.

[bulls23]

I have achieved longer sessions without problems simply by turning down the iPhone's display brightness. Especially in your case you won't be able to look at the phone anyway. I've done it with an Optrix case mounted to my helmet too:

[youtube]http://www.youtube.com/watch?v=vC-YHumLbtU[/youtube]

[ColinK]

Hi Both

Cheers for the swift reply's.

Bulls23 - like the footage you have from the Optrix case.
If i can get footage as good as that i will be very happy.
Point about brightness makes a lot of sense and something i will apply.

Do you know what length of sessions you have been able to do on 720p and on battery with the brightness turned right down?

Harry - Cheers for the feedback.
i didn't say in my post but my iPhone has nothing on it at all and has 13.5GB free space.
a lot more than the 7GB you have suggested for 720, would this be enough to take the 90min and apply the overlay ?

to be accurate 90 Min's is an over estimation.
My longest race of a month is a 60 min enduro with a 10 min qualifying.
other races are either 40 min enduros with 5 min qualifying or sprint event with 4/5 heats of 10 mins each.
it will be no hardship if i cannot get the whole of the 60 min enduro in HD

i will take a trial and error approach.
if i run out of space i will try a lower res.
if im not happy with that, its a works iPhone and im sure i can hustle a 32GB version if it comes to it.

i will turn the brightness right down as Bull23 has suggested to see how that helps with power.
At this time its really the video im interested in, with overlay if possible.

[Harry]

Overlaying space will not be the problem in your case as you overlay one lap at a time. These short videos for a kart track will requires 100MB max. In case you run out if space here, you can move overlaid laps to a desktop to get more space available.

- Harry

[bulls23]

Sorry I don't remember the max stint I recorded with my iPhone 4. The other day I logged seven laps of Nordschleife in video mode without recharging and without turning down the brightness, each lap around 9:30 but on my iPhone 5 and using my iPhone 4 as Multicam. The iPhone 4 wasn't recharged either and brightness wasn't down either...so if you ask me, recording of an hour shouldn't be a problem if the devices are fully charged and the batterys are alright. Never had a 4s.

[ColinK]

It was the long race today and happy to report that the iPhone/Lap Timer performed far better than my racing.
recording at 720p, brightness turned down to about 20% so can just about see screen when in the Optrix case.

total recording time 91:17
Space used 6836MB
Battery from full charge was about 15%
Looking forward to V18 with whole race overlay

[youtube]http://www.youtube.com/watch?v=E6gkga_x3iA[/youtube]

[ColinK]

Ah.

I tries to tell Laptimer to move to move the video to the library so i can get it on my PC and it tells me there is not enough space.
looks like it wants to duplicate it rather than just move it.

Anyway to get it on my PC from the app as opposed to duplicating it into the library ?
Or to tell the app just to move the video ?

[Harry]

Thanks for sharing your sample, good to have actual battery numbers to calculate with. I have changed the youtube embedding - it needs to follow the format shown here: viewtopic.php?f=22&t=1142

It seems your planning yielded great results!

- Harry

[bulls23]

Nice, looks pretty much like my video.