# Garmin 800 vs. 705 stats comparison



## Wherewolf (Jan 17, 2004)

So today I decided to run both my 705 and 800 on the same ride. However, I left the "auto pause" option on the 800. Here is a link that compares the stats side by side. Click on the "more detail" button. The 800 includes temperature. Next time I'll try the same setting for both. But this data begs the question, to use auto pause, or not use auto pause?


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## Harold (Dec 23, 2003)

Wow, that had to be some serious drift going on at lap 7 to rack up a whole mile in less than 10min. That right there pretty much amounts to your entire distance error between the two.


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## Wherewolf (Jan 17, 2004)

*Slow speed?*



NateHawk said:


> Wow, that had to be some serious drift going on at lap 7 to rack up a whole mile in less than 10min. That right there pretty much amounts to your entire distance error between the two.


That was a long slow climb and I had to push my bike a few times. Do you think that the auto pause is coming on if it thinks I'm stopped, even though I'm riding very slowly and/or pushing my bike? I think I'm going to turn auto pause off. It certainly is underreporting my mileage. Even if I'm going slow or pushing my bike that mileage counts


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## Harold (Dec 23, 2003)

If you were not stopped, but moving slowly up a hill, it sounds like auto pause might be doing it. To lose a whole mile out of less than 6 is a bit much.


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## Psycho Mike (Apr 2, 2006)

Are you running just the GPS, or do you have the speed/cadence sensor too?

For myself, I noticed there was a hair bit of a difference between my Edge (a 305) and a "regular" bike computer when dealing with the auto-pause (like maybe 250 ft in a 20 mile ride when there were lots of starts and stops), but nothing like that 1 mile.

The biggest thing I find with the GPS's is that they seem to record horizontal distance and let the altimeter do the rest. In hilly terrain, I find that there was more of a difference in what the GPS alone would tell me vs. what a "normal" bike computer did.

I added the Speed/Cadence sensor to my set-up and, although the GPS doesn't always go to the sensor for info, it has seemed to help refine it a bit more.

Of course, this is IME, and YMMV.


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## shiggy (Dec 19, 1998)

NateHawk said:


> If you were not stopped, but moving slowly up a hill, it sounds like auto pause might be doing it. To lose a whole mile out of less than 6 is a bit much.


That sounds likely to me. With my 305 the %grade stops displaying below ~2.5mph.

I use the setting in Ascent (Mac software) to adjust the moving time after downloading.

There is an 800 in my future.


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## Wherewolf (Jan 17, 2004)

*Topofusion says...*

Topofusion shows the same total distance for both units. But is shows 13.72 mi uphill distance for the 705 and only 4.95 mi uphill distance for the 800! I'm turning auto pause off!


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## slocaus (Jul 21, 2005)

Yes, on my 705 (and 305 prior) the auto pause has a lag of when it stops recording and starts recording; I have the beeps on, so I know when it starts and stops. If I am climbing slow in tree cover and north slopes, it will auto pause. When I have to get off and push, it is especially noticeable that the lag of start can very late compared to my moving on auto stop and start.

I had not really thought about the effects of using auto pause on distance. I have always used it on both units, since I have a Time and Paused Time screens on the display. Sometimes I want to keep moving and it works. Other times, when I ride out to do trail work, I want to know ride time separate from work time.

I'm going to experiment with auto pause off.

Wherewolf, since you have two units, some comparisons with both units auto pause and no auto pause will really shed some light on this, I'm thinking.


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## Wherewolf (Jan 17, 2004)

*Next ride*



slocaus said:


> Wherewolf, since you have two units, some comparisons with both units auto pause and no auto pause will really shed some light on this, I'm thinking.


Next ride, perhaps tomorrow, I'll try no auto pause on both.


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## Wherewolf (Jan 17, 2004)

*Another test*

I did another side by side test on a ride today. The 800 has a more accurate altimeter. I know this because I have a known elevation point to compare them. The 705 was as much as 50 feet too low sometimes. To test consistency laps 2, 3 and 4 are the same loop.


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## Harold (Dec 23, 2003)

Interesting. The Edge 705 measured exactly the same distance for your 3 laps of the same loop, but the 800 was a little different each time.

HR was pretty much the same AFAICT.

Elevation is quite different. Almost 800ft over 27mi. That's pretty significant. Can you post screenshots of the Topofusion Climbing Analysis for these two rides? I'd like to see how those numbers compare to other elevation measures like the DEM-based data.


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## Wherewolf (Jan 17, 2004)

*Topofusion*



NateHawk said:


> Can you post screenshots of the Topofusion Climbing Analysis for these two rides?.


What does all this mean and how can they be so different? All the stats are considerably different in Topofusion. I would accept about 2,100 ft of climbing there as indicated by the 800. There is no way I could get 3,600 ft. of climbing as indicated by the 705.


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## Harold (Dec 23, 2003)

That's interesting. The DEM value should be about the same between the two rides, since both rides are overlaid upon the same DEM data. That tells me there's a positional accuracy difference between the two. Most DEM data that's easily accessible has a 30m resolution, so it's going to lose out on a lot of fine detail elevation changes, but it'll be consistent over the entire ride.

Can you post a screenshot of the two tracks overlaid on each other?

How many track points are contained within each file (also, what's the set recording frequency of each GPS)?

One thing I notice from the 705 is that the elevation drifts slightly downward over the course of the ride. You can see it by comparing your start/finish points (should be the same, of course). The 800 keeps the start/stop pretty close to the same and I don't see any obvious drift.

I would really like to see elevation profiles for at least some of the choices in Topofusion's Climbing Analysis, but I can't figure out how to get more than one plot up (and only for whatever elevation values are recorded in the file).


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## Wherewolf (Jan 17, 2004)

*Download*



NateHawk said:


> Can you post a screenshot of the two tracks overlaid on each other?
> How many track points are contained within each file (also, what's the set recording frequency of each GPS)?I would really like to see elevation profiles for at least some of the choices in Topofusion's Climbing Analysis, but I can't figure out how to get more than one plot up (and only for whatever elevation values are recorded in the file).


Download the two files and you can play with them all you like. The 800 has more than twice as many track points as the 705.


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## slocaus (Jul 21, 2005)

Wherewolf said:


> Download the two files and you can play with them all you like. The 800 has more than twice as many track points as the 705.


How do you have the 705 set to record tracks? I know it can be set for Smart or One Second recording, and the 800 only has Smart, unless you have a Power Tap paired that allows One Second.

So this implies that the 800 uses a different "Smart" algorithm than the 705. Good information coming from these comparisons. Keep testing.


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## Wherewolf (Jan 17, 2004)

*Smart*



slocaus said:


> How do you have the 705 set to record tracks?


Smart.


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## felix5150 (May 7, 2008)

Did you do the software update on the 800? There are some autopause issues resulting in the distance being off if you don't upgrade to v 2.1


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## Wherewolf (Jan 17, 2004)

*Another big test*

Rode with both units again today on a much longer and more varied ride. The 705 is way off. I see there is a software update available. I'll try it and see if it helps. Here is a side by side comparison. Laps 2 and 4 are the same trail but in opposite directions.


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## KingOfTheHill (Sep 19, 2007)

FWIW, I have a similar problem with with my Oregon 450. My Edge 800 and 705 are usually within a few feet of each other but...the Oregon has consistently been giving me 3-4 times the elevation gain the other units give, once five times the gain. It's frustrating, especially since I've tried everything short of sending the 450 to Garmin.


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## GrayBeard Pirate (Dec 26, 2009)

What are the differences in the 705 and the 800 besides the obvious touch screen?


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## KingOfTheHill (Sep 19, 2007)

Differences are:

File format
1 sec recording available on 705 w/o power meter
Birds eye imagery on 800
Can use multiple maps simultaneously on 800
Can do more fields on the 800 screen
705 screen has much better image quality, easier to view

Some other stuff I can't remember


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## Harold (Dec 23, 2003)

Looks to me like it's the Edge 800 that's off in this case. Times are close enough to be insignificantly different.  The 705 got the distances between the two laps of the same trail right, but the 800, not quite.

I'm assuming on this test you have both set to the same recording frequency? 1sec?

Still, I'm not sure a 0.18mi overall difference over more than 32.5mi is a statistically significant difference.



> FWIW, I have a similar problem with with my Oregon 450. My Edge 800 and 705 are usually within a few feet of each other but...the Oregon has consistently been giving me 3-4 times the elevation gain the other units give, once five times the gain. It's frustrating, especially since I've tried everything short of sending the 450 to Garmin.


How often do you calibrate the altimeter on the Oregon? Keep in mind that the Edge models have auto-calibration for the altimeter, but the Oregon series do not. On the Oregons, you have to manually calibrate the altimeter to known points.

I recently had an elevation change reading from a ride with my Oregon at ~6000+ft on a ride that I KNOW has only 100-200ft of elevation change from the highest to the lowest point. It gave me that reading because of atmospheric drift from a weather system moving through over the course of my ride. It was a low pressure system, as indicated by the fact that the wind kicked up and the skies cleared out while I rode.

Understand the tool you are using and you will understand why it collects the readings it does.


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## KingOfTheHill (Sep 19, 2007)

NateHawk said:


> How often do you calibrate the altimeter on the Oregon? Keep in mind that the Edge models have auto-calibration for the altimeter, but the Oregon series do not. On the Oregons, you have to manually calibrate the altimeter to known points.
> 
> I recently had an elevation change reading from a ride with my Oregon at ~6000+ft on a ride that I KNOW has only 100-200ft of elevation change from the highest to the lowest point. It gave me that reading because of atmospheric drift from a weather system moving through over the course of my ride. It was a low pressure system, as indicated by the fact that the wind kicked up and the skies cleared out while I rode.
> 
> Understand the tool you are using and you will understand why it collects the readings it does.


The Oregon 450 DOES have auto calibration but I keep it off and manually calibrate before each use. I know what I'm doing with it and how to use it, it just is not reliable in my experience. Of course, I might just have a bad unit and should send it in.


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## slocaus (Jul 21, 2005)

GrayBeard Pirate said:


> What are the differences in the 705 and the 800 besides the obvious touch screen?


--> Easy answer link <--

There are more technical details that may or may not matter, depending on your use.

- one second recording or smart recording on 705; smart on 800 only unless you have a power tap to get one second.
- different file format
- temperature only with 800
- custom maps only with 800
- touch screen only on 800
- I have only seen one 800 in the wild, but my 705 screen is much clearer to see


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## Harold (Dec 23, 2003)

KingOfTheHill said:


> The Oregon 450 DOES have auto calibration but I keep it off and manually calibrate before each use. I know what I'm doing with it and how to use it, it just is not reliable in my experience. Of course, I might just have a bad unit and should send it in.


Have you compared your current use with the auto calibrate? How long are your rides? Mine with the 6000' of elevation change fluke due to changing weather occurred over only a couple of hours. To keep the altimeter in check, I would have had to calibrate it every few minutes - or use auto calibrate. I didn't worry about it. I just scrapped the elevation data from the altimeter and overwrote it with the DEM elevations.

This is the ride the GPS indicated had such a huge elevation change.








Not even possible for 6000' to occur in less than 3 miles. The GPS did freeze up at one point. Never had that happen before, and it may have something to do with the erroneous elevations.

This is the sort of thing I typically get from the GPS.








This comes from the barometric altimeter. The first climb in both rides is the same stretch of trail. Pretty close between the two. IME, the altimeter has been reliable but with the possibility of atmospheric drift. The second ride illustrates that, because the peaks of each climb are at the same spot (multiple trails converge at the top of one hill) and as such should be at the same elevation. But due to atmospheric drift over the course of the ride, those elevations change slightly.


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