Okay I just got my new Fenix 5X and took it running yesterday set on Smart mode recording. I run in the open countryside on basically straight roads and tracks and no powerlines. I ran 12km yesterday however during the entire run (on Smart mode) the track shown and recorded is wildly erratic throughout. Ludicrous - totally unusable! Why? Tried it today on 1sec record and it's fine. (Why no 5sec record these days?)
I personally use 1 sec - gps+glosnass. Found smart to do odd things.
It could also have been the gps wash hadn't occurred on the watch if it was the first time out. Could try another smart run to see if that too is better.
Thanks ikim - 1sec/gps/glonass is okay for day-to-day runs but for ultramarathons I need to extend the battery life for as long as possible - I thought using 'Smart' mode.
[FONT=Helvetica Neue]UltraTrac setting will extend the battery life at the expense of GPS accuracy. Smart mode just records less points and uses less memory - hence last longer by not filling up the memory. At least that's how I understand.[/FONT]
Listen from 37:21 - 38:22 - if I understand correctly smart mode only saves space, but has no impact on battery life vs. 1s. In other words, there is really no reason NOT to record on 1s. Speaker on Podcast is DC Rainmaker.
Thanks for the responses but... still doesn't answer the original question as to why is Smart mode so totally crazy erratic? I'm talking a violent 80degrees left of track for 10metres+ then back immediately 80degrees right of nominal track for 10m+ then back immediately 10m+ left of nominal again (etc etc etc) - throughout the entire 12km+ run/s. basically a continuous zig-zag line the entire way. What's the point of Smart mode?
I've been using smart recording ever since I got my first FR310XT. Now I use a FR735XT and use smart recording, too. What I found out over the 8 years is that smart recording completely looses it when doing a downhill slalom (frequent rapid changes in direction). The speed and distance is okay-ish, but the GPS track on the map is somewhat screwed. I never found any other scenario that would give such results. This is a clear deficiency of the smart recording algorithm, although it never really bothered me much. But if it is not acceptable for you, then there is a simple workaround. Just use 1 sec recording if it works better. There is no additional cost to it except a slightly larger file.
Thanks ikim - 1sec/gps/glonass is okay for day-to-day runs but for ultramarathons I need to extend the battery life for as long as possible - I thought using 'Smart' mode.
You will not save any battery life with "Smart" mode as it was already mentioned. Regarding the result you've got, it was most probably due to the different conditions. Quality of GPS signal may vary from hour to hour, from day to day (and place to place, of course). What you did is simply not comparable. Try to do at least several runs using Smart mode enabled and check whether it is always equally erratic. I have only good experience with Smart recording, no significant differences even if running at stadium on oval track. There should not be big difference in trajectory for Smart vs 1sec recording especially if you run mostly straight. :)
When I see lots of sharp, very angled lines I find its lost the GPS tracking and just drawn a line between the point it had it and the point it got it back again. I'll sometimes see those on forest rides in heavy sections of tree cover, sometimes on the same section I'll see a good track. Guess it depends on positioning, weather etc.
I don't know the exact logic behind the smart mode. Personally I found I had more 'lines' with it than with 1 second, others seem to use it just fine. I think its (Smart mode) more a throw back to early days where the devices had much less memory though and space was premium.
I think you have to find the best combination for the location you are in. GPS+GLOSNASS, GPS ONLY, SMART + 1 second. Some people swear by one setting that just seems rubbish for others.
