The Greek

So, I wanted to squash all the debate on how accurate the Harrys Lap Timer is. I finally setup everything, and went out to Sebring this weekend with Chin.

Details: It was partly cloudy, but mostly sunny. Signal strength was full, if not maybe 1 bar less from full. I used a TomTom cradle with the power a/c unit plugged in.

Harry's Lap Timer (TomTom Cradle)

2:25.33
2:29.55
2:28.44
2:28.15
2:46.27

TraqDash (Newest version of Traqmate)

2:25:36
2:29.47
2:28.44
2:28.09
2:46.47

I was shocked at how accurate Harry's Lap Timer was. I personally believed it would be a .5 to 1 second time difference from a actual Data Aquisition System. As you can see, the difference was a an average of .07 seconds. That is CRAZY accurate for a $14.99 app vs my $3500 system. Now granted the data analysis is much less detailed than my Traqmate, but if you are a average DE driver, this is a must have.

NOTE: I did a 3rd session with the cradle unplugged, but for some reason, it did not detect start finish, and didnt work. I then had to let a friend borrow the cradle for his iphone, so the day of testing was over. I have heard however that the app is NOT as accurate without the cradle. Vastly improves the signal. The next event I go to, I will do a session with the Harry's unplugged, and will document the difference. Hope this helps guys....

Nick

jenk12m

Hard to argue with that

24Chromium

The cradle doesn't help with the GPS signal, it doubles (or more?) the sampling rate (number of GPS fixing cycles per second) of the GPS. That's where the magic is, since you are a very quick moving target!

CRex

I've had very consistent results with HLT plus a TomTom cradle over the past three years. The accuracy is definitely there--the times are easily within 0.1 sec of my (then) beacon-based timer and (now) Aim SoloDL. It is really the best 10 bucks one can spend on AppStore.

And truth be told, despite the vastly expanded capabilities of a dedicated datalogger I still find myself running HLT side-by-side the new SoloDL. HLT's just much easier to get high-level data out of right after a session and its visualization is a grossly underrated feature.

9972RS

I've contemplated this also.

HLT with an external GPS sensor/cradle is pretty accurate when compared to an AIM Solo.

However, the main question is for video. Do I ditch the smartycam with integrated overly and non-HD video and use HLT with an external GPS? Smartycam $1,000. HLT $20 + ext. GPS = under $100

andrewdr

Does the tom Tom plug into iPhone?

The Greek

Yes, the iphone 4 plugs directly into it.

senna

I was looking for a TomTom cradle today, but I think they stop making them. Where did you get it?

orthojoe

Using the emprum ultimate gps plug in will get you the best accuracy for HLT. 5 Hz vs 1 Hz.

AiM solo runs at 10Hz. No doubt HLT works well as a laptimer. I moved on because of limited exporting capabilities to make my own videos, and wanted to log more data channels at higher frequencies. You still can't beat the visual interface of HLT

The Greek

I bought the TomTom from Best Buy

NJ-GT

What about iphone4 without cradle, is it accurate? I saw Clarke lapping in 4 minutes and 45 seconds, and he looks faster than that at Sebring.

I bough HLT ages ago, but haven't used it yet. I will give it a try next time to validate against the AiM SOLO DL which is pretty accurate.

9972RS

without the external gps, it's not very reliable.

The videos are a lot better than a smartycam.

M3EvoBR

still tenth of a second give or take.

CRex

Rad: without the aid of external GPS, HLT isn't half as good. Give or take half a sec in my experience just suction-cupping my iPhone to other people's cars. More importantly, the lack of accurate datapoints relegates it to a simple timer (i.e. track plots incomplete and straight/corner speeds missing)

The data rate for TomTom is only 1Hz, but that already gets me to within 0.05–0.1s of my SoloDL. Haven't tried the other external sensors mentioned above but I surmise that anything above 1Hz will suffice.

As an OT: I am earnestly struggling to make sense of my setup. I used to run only a SmartyCam (with data) and HLT for visualization of laptimes and immediate post-run timing. Problem is that SmartyCam is horrible with video quality and HLT limited with data. So I got additional GoPros and a SoloDL. Now I have data and video and data feeds coming out the wazoo but no logical workflow around all that...

I see a potential solution in Trackvision, but that doesn't do proper video overlays and transitions like dedicated videoediting tools... Has anyone seen tools that generate only a "dash" with data which can then be imported into the likes of iMovies or Premiere?

orthojoe

I use trackvision, then post process with adobe premiere elements 10