Does the Garmin 305 (or 405) have a backlight? How accurate is it at the track? (Read 2299 times)

I'm unexpectedly in the market for a new HRM as my old Polar one broke. I'm thinking about the Garmin 305. Does it have a backlight? One thing that irked me about my Polar S120 is that it did not have a backlight - so when I was doing my pre-dawn speedwork at the track I did not know how fast my intervals were until later that morning when I checked the lap times in my watch. Will I be in the same boat with a Garmin Forerunner? Actually, how does the Garmin perform at the track? Is it accurate? (not that I need a GPS unit to tell me how far I've run at the track, but I believe there is an auto lap feature on the Garmin...will that work at the track?)

Yes, it does have a backlight. Very readable. There are a few different types of auto-lap. One is fixed distance, another is one where it auto-laps when you pass the start of your loop again. You'd probably want to use that 2nd one. Is it accurate? Depends on your tolerance. Anecdotally, I'd say it's within ±1~1.5% of the total distance run. Good enough for most applications, though I would just hit the lap button on the track and look at the splits rather than fart around with trying any auto-lapping. Also, the lap pace takes about 0.2mi to converge on a stable reading. So basically, the GPS aspects are pretty useless on a track for intervals. I think the technology would get in the way of the workout. In order to post to this thread, your screen name must end in goblue.

... another is one where it auto-laps when you pass the start of your loop again. You'd probably want to use that 2nd one. ...

Can the 205 do that?

- the backlight comes on every lap when it is dark out (how does that work, btw? I guess it has a light sensor?)

No, you just can't really see the backlight in the daylight.

- but the autolap is based on its measured distance and

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- it is a bit inaccurate at the track - on the order of up to 5% I've observed I think

Hmm. perhaps measurement error gets compounded if you're running the same small course repeatedly. That still sounds high to me.

how does that work, btw

You tell it that it is dark out by turning on the backlight at the start of your run. You know, when you look to make sure the thing is on and set right? If you do not do that, it won't auto-light. Cool, eh?

You tell it that it is dark out by turning on the backlight at the start of your run. You know, when you look to make sure the thing is on and set right? If you do not do that, it won't auto-light. Cool, eh?

Trentopedia rocks!

In the winter months, when nearly all my runs are in the dark, I just set the backlight to have no timeout so that it stays on from the time I press it until I turn off the unit. I haven't seen a significantly noticeable change in battery consumption from running the light all the time. Plus its another light waving around in the dark to keep people from running me over, but that's probably not a problem on most tracks.

The backlight works (as Trent mentioned) by coming on if you have used it manually in the run. The watch is also aware of the sunrise/sunset times; it'd be a cool feature if it based its lighting on that. I've used my 305 as a stopwatch on a track. When I look at the laps afterward, it always shows .25 miles for a single lap, so it is pretty accurate. Personally, I'd stay away from autolap anyway since that .25 could actually be as high as .259 which is a pretty big difference over such a short distance.