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I canceled my Garmin Colorado 300 order

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........Basically he told me the chipset was the same in the 60csx and the colorado and the H series........

Someone correct me if I am wrong, but the 'H' series units use the SiRF Star III chipset not the Garmin chip that is used in the Nuvi and the Colorado. It will be interesting to see how the on road Nuvi's chipset will stand up to off-road use. I am curious if it will have accuracy issues like the Garmin's used to before the 'H' series and the adoption of the SiRF chip.

 

Maybe they don't know how big Geocaching is... maybe they need to hire someone to do PR here... I wonder where I could find an application?

Geocaching in not that big, as geocachers we would like think it is. But I am sure that the automotive, aviation and marine markets are much larger.

I think you are comparing apples to oranges here. You can't compare handheld use to auto or aviation use, or for that matter a marine application to a TOPO application. Comparing apples to apples; if you look at the number of people that would buy a handheld TOPO GPSr, the numbers are probably pretty evenly split between backpackers and geocachers (with some industry applications thrown in as well). SO, I would say that in that regard Geocachers are a pretty large part of the target demographic for the TOPO GPSr companies out there. That being said, I think that the Colorado was a great concept, it just fell short of the bar in several areas.

 

No I am not comparing apple to oranges

I said; Geocaching is not that big, as geocachers we would like think it is. But I am sure that the automotive, aviation and marine markets are much larger.

Just look at how Garmin promotes GPS sales.

I have seen lots of television advertising for the Garmin automotive units. A company spends it advertising dollars were it generates most of it's income. About the only TV add I recall that featured a hand held GPS was a battery add, and it was not geocaching related.

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I assume StarBrand wrote "I see no problem", because to him, it's not a problem.

We all have our opinions, but it's not fair to request that some throttle theirs, just because they don't share your's.

 

Getting positions at a favorable time is often better than averaging the position. But the latter is very easy to do, of course. But to get the best result, you need prediction software to know when to go out there.

 

Some old, but interesting reading.

 

Here's a quote from another source:

Several interesting effects of averaging GPS positions can be seen from the chart. For averaging periods of less than approximately a minute, little effect is had on the accuracy of a positional determination. For averaging periods between a minute and an hour or two, a fairly consistent improvement in accuracy is obtainable. Averaging for longer periods naturally continues to improve accuracy, though the rate of improvement decreases.

 

Most users have no idea about how long it takes to get significantly better values.

 

Anders, yet another loyal defense of the shortfalls of the Colorado.

 

So what your saying is that the fact the Colorado is missing waypoint averaging is GREAT! Its BETTER! Its NOT an oversight, it was planned because NOBODY averages waypoints because it "DECREASES" accuracy. What Bunk!

 

That line of thinking is absurd to me. Why can't you just say something like, yeah, thats crap and I hope they add that feature in a future update.

 

Anders, man, we all love you here on these posts for the valuable information and insight that you offer, but to defend a lack of features by saying that it's better without and it and was planned that way, kind of stump me sometimes. I guess all I'm saying is that your opinion, as a beta tester and very knowledgeable individual, is valued and it sucks when it comes accross (at times) to be biased.

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Being a Design Engineer for consumer electronics like the Colorado, I always find it interesting to read the forums. One thing to consider is what percentage of the customers are represented by the unhappy posters in this forum. A wild guess would be that Garmin is expecting to sell 100K-200K of these units a year. Over a five year product lifetime lets guess 500K total units sold. So out of 500K Colorado owners, how many are hardcore geocahers? How many geocache at all?

 

So if you have 500,000 customers and 20 of them are complaining, how much weight do you give those complaints. Do you expect the company to invest hundreds of thousands of development dollars to make a couple hundred dollars of profit? Doesn’t sound like that company is going to be around very long using that business model.

 

I am an avid mountaineer, adventure racer, and hiker. I geocache on occasion when my daughter is along to make trips a little more fun. Gps units are not just for geocaching. I have been caught in whiteout conditions on a mountain miles from base camp several times where without a GPS I could not have navigated at all. I also work on a search and rescue team, and the GPS is indispensable for coordinating an effective wilderness search. As an adventure racer, I use the GPS to monitor all my stats like average speed, mileage, and elevation change along with navigating the race. The Colorado works great for my use which includes the occasional geocahe. I have nothing against goecachers, I consider myself one, but I think you complainers need to step back and look at the big picture. There are people out there using these units to save their lives and the lives of others. There are athletes using them to monitor their performance, and there are of course, the geocachers. Garmin needs to make the best unit for all their customers, not just the extremely small percentage represented here.

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Most users have no idea about how long it takes to get significantly better values.

Back when I was using my Sportrak color, I used to average for 5 minutes when placing a cache. I found that any longer produced little difference. One rule of thumb I used, was that if the reading hadn't changed in 1 minute, it was probably accurate enough. The eXplorist line didn't do averaging, and I kinda missed it, but I really didn't fret much over it. If they add it to the Colorado, it would be cool, but I really don't think it's that big a deal to me personally.

 

--Marky

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Getting positions at a favorable time is often better than averaging the position. But the latter is very easy to do, of course. But to get the best result, you need prediction software to know when to go out there.

 

Some old, but interesting reading.

 

Here's a quote from another source:

Several interesting effects of averaging GPS positions can be seen from the chart. For averaging periods of less than approximately a minute, little effect is had on the accuracy of a positional determination. For averaging periods between a minute and an hour or two, a fairly consistent improvement in accuracy is obtainable. Averaging for longer periods naturally continues to improve accuracy, though the rate of improvement decreases.

 

Most users have no idea about how long it takes to get significantly better values.

 

Averaging has come in handy a few times while in steep valleys with heavy tree cover. Obtaining and holding a signal can be a real challenge. I let my Vista HCx sit and average about 500 samples on three different days. Then I took those three averages and averaged them to obtain an average of the averages. Now how long would it have taken me to individually mark 1,500 samples??

 

I don't have a problem with others having an opinion on the Colorado. If they think the Colorado is the cat's meow, then they can go right ahead skipping down the trail in utter bliss. I just don't appreciate people minimizing the concerns of others as being irrelevant when many of the issues are glaring and obvious.

 

BTW, I really appreciate all the information and insight you have been able to provide. The nice thing about a dialogue like this is that people can air all of the strengths and weaknesses of the system so that others can make an informed decision on weather to purchase a Colorado.

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Being a Design Engineer for consumer electronics like the Colorado, I always find it interesting to read the forums. One thing to consider is what percentage of the customers are represented by the unhappy posters in this forum. A wild guess would be that Garmin is expecting to sell 100K-200K of these units a year. Over a five year product lifetime lets guess 500K total units sold. So out of 500K Colorado owners, how many are hardcore geocahers? How many geocache at all?

 

So if you have 500,000 customers and 20 of them are complaining, how much weight do you give those complaints. Do you expect the company to invest hundreds of thousands of development dollars to make a couple hundred dollars of profit? Doesn’t sound like that company is going to be around very long using that business model.

 

 

Thanks for your input. Garmin wouldn't have to spend anything on R&D since they already have the requested and expected functions in their other units. The only new features are the "paperless" feature and the "rock-n-roll" interface.

 

If Garmin was not targeting geocachers then why the "geocaching mode?"

 

If you want to talk about business models, we could go on all day. What it comes down to is that when a company finds features that work, why would you eliminate those features? That would not be a very wise business model.

 

OK...Why doesn't someone start an "I Love My Colorado" thread so we can all hear about the wonderful features and improved functionality of the Colorado?

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Garmin wouldn't have to spend anything on R&D since they already have the requested and expected functions in their other units. The only new features are the "paperless" feature and the "rock-n-roll" interface.

 

As far as I can tell, the main problem is that this is the first handheld using this "operating system". All previous ones used the same basic OS from the first Garmin units. They changed to a completely different OS on the Automotive units a little while ago and have used it for this unit. Unfortunately, they have not transfered ALL of the functions from the old units over.

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OK...Why doesn't someone start an "I Love My Colorado" thread so we can all hear about the wonderful features and improved functionality of the Colorado?

 

1) Larger, higher resolution screen

2) Ability to store and display all the Geocaching information in a GPX file.

3) Shaded relief views possible.

4) Waypoints store timestamp and elevation.

5) Waypoint name limit increased.

6) Unlimited track storage on the internal memory.

7) Large internal memory.

8) Can wirelessly transfer waypoint data

9) Can wirelessly receive heart monitor and bike speed/cadence signals.

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Being a Design Engineer for consumer electronics like the Colorado, I always find it interesting to read the forums. One thing to consider is what percentage of the customers are represented by the unhappy posters in this forum. A wild guess would be that Garmin is expecting to sell 100K-200K of these units a year. Over a five year product lifetime lets guess 500K total units sold. So out of 500K Colorado owners, how many are hardcore geocahers? How many geocache at all?

 

So if you have 500,000 customers and 20 of them are complaining, how much weight do you give those complaints. Do you expect the company to invest hundreds of thousands of development dollars to make a couple hundred dollars of profit? Doesn’t sound like that company is going to be around very long using that business model.

 

I am an avid mountaineer, adventure racer, and hiker. I geocache on occasion when my daughter is along to make trips a little more fun. Gps units are not just for geocaching. I have been caught in whiteout conditions on a mountain miles from base camp several times where without a GPS I could not have navigated at all. I also work on a search and rescue team, and the GPS is indispensable for coordinating an effective wilderness search. As an adventure racer, I use the GPS to monitor all my stats like average speed, mileage, and elevation change along with navigating the race. The Colorado works great for my use which includes the occasional geocahe. I have nothing against goecachers, I consider myself one, but I think you complainers need to step back and look at the big picture. There are people out there using these units to save their lives and the lives of others. There are athletes using them to monitor their performance, and there are of course, the geocachers. Garmin needs to make the best unit for all their customers, not just the extremely small percentage represented here.

 

If you take notice, the Colorado is not marketed as a "Fitness Unit", nor is it marketed as a "Street Navigator" it is marketed as a handheld outdoor navigation unit. They cater to users of these other generas in other products designed to do certain things. The bikers, the joggers, the others, all have their own niche products.

 

No, given that this is a handheld mapping outdoor navigator it is expected to do certain things. It is expected to have a certain feature set designed to be used as a navigation tool.

 

I don't geocache much, on occaison I will, and its fun. What I use the GPS for, and so many others, is to navigate outdoors and record data. Now these "navigation" features arent "specialized", these features are common and expected in a handheld GPS.

 

Seeing how this is a forum on geocahing, GPS's and the like, I would feel negligent if I wouldn't air my opinions, facts, and findings on the GPS units discussed.

 

Believe it or not dopoka, LOTS of people search Google before dropping $500 on a GPS. A great many topics from this forum show up on the Google search. Therefore, the general comments and opinions of those on this forum who discuss them intelligently are seen and digested by many. How many people have been disuaded from buying the Maggie Triton by reading the google searched reviews and forums? ALOT! (me included) Trust me, if there are shortcommings of a particular GPS unit and people are dissapointed it will get around and effect sales in a larger way than you imply. One more thing, how many GPS salesfolks search the internet to read about opinions, defects, and shortcomings of particular units before recommending them to customers? You may see it as griping etc. but you miss the larger picture in doing so.

 

Question for the engineers: Do you guys actually use the products you design? :laughing:

 

All in good fun of course.

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OK...Why doesn't someone start an "I Love My Colorado" thread so we can all hear about the wonderful features and improved functionality of the Colorado?

 

1) Larger, higher resolution screen

2) Ability to store and display all the Geocaching information in a GPX file.

3) Shaded relief views possible.

4) Waypoints store timestamp and elevation.

5) Waypoint name limit increased.

6) Unlimited track storage on the internal memory.

7) Large internal memory.

8) Can wirelessly transfer waypoint data

9) Can wirelessly receive heart monitor and bike speed/cadence signals.

 

With that said, how would you rate your Colorado on a scale of 1 to 10 with 10 being "it is everthing I expected and more" and 1 being "what a waste of $550.00?"

 

If you could do it all again, would you have still purchased your Colorado or would you wait until the dust settles?

 

Overall, is the Colorado better or worse than the existing Garmin line-up as far as it's geocaching features and functions?

 

Is the Colorado a better navigational tool than other existing units?

 

Would you recommend the Colorado to another geocacher at this time?

 

.....and remember, honesty counts.

Edited by 3 Hawks

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With that said, how would you rate your Colorado on a scale of 1 to 10 with 10 being "it is everthing I expected and more" and 1 being "what a waste of $550.00?"

I don't have one. And they are only $400...... :laughing: I don't need US topo map and even if I did, I wouldn't pay $100, when I can make them for free....

 

Overall, is the Colorado better or worse than the existing Garmin line-up as far as it's geocaching features and functions?

Overall a little better......

Map display is the same (for me).

Can read all the information which is a huge plus.

Can't mark a cache as found, which is slight negative.

Can't average, which is a slight negative..

 

Is the Colorado a better navigational tool than other existing units?

The same. The changes are certainly not going to do anything to make it better for navigation. And really, there is nothing that they could do to make it better. The "X" line does everything anyone could ask as far as navigation goes and this one does all of those things.

 

Would you recommend the Colorado to another geocacher at this time?

Depends on budget. If you are a money no holds person, then sure. Best bang for the buck is a Legend Hcx.

Edited by Red90

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Anders, yet another loyal defense of the shortfalls of the Colorado.

 

So what your saying is that the fact the Colorado is missing waypoint averaging is GREAT! Its BETTER! Its NOT an oversight, it was planned because NOBODY averages waypoints because it "DECREASES" accuracy. What Bunk!

 

Huge 10-4! I was taught in high school chemistry lab to weigh all samples THREE times and average them.

 

Anybody else have that experience from chemistry lab (high school or college)?

 

Are thousands of chemistry teachers and professers wrong?

 

What complete and absolute rubbish! :laughing:

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"Question for the engineers: Do you guys actually use the products you design?"

 

Actually I do use the products I design, along with millions of other people. The truth is I don't always like the features or operation of my products, but I don't get to decide what features are included. Generally marketing and upper management makes all the decisions on product features and operation. Engineers are given the specifications for the design, and if it possible we try to meet those specifications. I would love to tailor the products I design for "me" but since millions of other people have to use them, they are designed with the average user as a target.

 

The firmware issues that have been noted are most likely due to schedule pressure to get something out to compete with the Triton. Engineering is often put under great pressure and forced to release products with known issues to meet the schedule. You can thank upper management and marketing again for this one.

 

Don't get me wrong, I think all the input is good. I surfed these forums before I bought, and they stopped me from buying a Triton when they came out. I'm just saying I'm sure Garmin is doing everything they can to satisfy as many of their customers as they can. I think the platform is solid, and will prove to be a great unit over time.

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Most users have no idea about how long it takes to get significantly better values.

Back when I was using my Sportrak color, I used to average for 5 minutes when placing a cache. I found that any longer produced little difference. One rule of thumb I used, was that if the reading hadn't changed in 1 minute, it was probably accurate enough. The eXplorist line didn't do averaging, and I kinda missed it, but I really didn't fret much over it. If they add it to the Colorado, it would be cool, but I really don't think it's that big a deal to me personally.

 

--Marky

It could be that with the improved chip sets from SiRF and other companies and with the WAAS birds that we did not have few years ago that waypoint averaging may not needed as much as it was in the early days of GPS techology.

The one thing I do not like about the Colorado is the PRICE !! :laughing:

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Averaging is ALWAYS better. Its called an increased sample size, I'm sure we have a few people on this forum who took stats in highschool.

 

Those of us in natural resources who collect data are often required to average for a set amount of time to increase the accuracy of the data. To those geocache-only users averaging may not be a big deal, but to the rest of the world, the Forest Service, State Agency personnell who use these things as serious navigation tools and to collect data for ArcGIS applications, waypoint averaging is an absolute necessity.

 

I keep noticing the dichotomy between geocachers and hiking/navigational/data collection users. Maybe Garmin should start a new marketing strategy geared just towards geocachers. That's what the Colorado seems to be anyway.

Edited by yogazoo

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<snip>

 

So what your saying is that the fact the Colorado is missing waypoint averaging is GREAT! Its BETTER! Its NOT an oversight, it was planned because NOBODY averages waypoints because it "DECREASES" accuracy. What Bunk!

 

That line of thinking is absurd to me. Why can't you just say something like, yeah, thats crap and I hope they add that feature in a future update.

As Red90 said, this is the first handheld unit to use the same base software as the car units. I'm guessing it's an attempt to unify their software development (it's what I'd do if I were them). Obviously, the car units are lacking many of the features we expect in a handheld unit.

 

And as dopoka said, in most product companies, the features and the timeline are set by marketing. The timeline was release for CES 2008, obviously, and missing that would have been a huge loss, if only because everyone expected something new from Garmin at CES. So, the timeline was fixed. When you have a list of features and a fixed timeline, engineers have to make compromises when the inevitable delays crop up. So, Garmin focused on the "glitzy" features (GPX file support, terrain shading, 3-D view, the new Wherigo games) and the older "standard" features went missing. It's the rational thing to do--most bang for your buck (or timeline in this case). A company like Magellan sacrifices quality instead to meet a (multiply-slipped) timeline.

 

Yes, it would have been great to have all the features from the old handhelds and more, but sadly, reality intrudes. We can wish and hope and complain, but ultimately wait to see if Garmin makes the Colorados the "ultimate" geocaching GPS (there will always be some people who aren't satisfied). Quite a few people have enough trust in Garmin (and patience) to have bought them already, despite knowing their current shortfalls.

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Averaging is ALWAYS better. Its called an increased sample size, I'm sure we have a few people on this forum who took stats in highschool.

I think the point that Anders was trying to make was that averaging can give you a false sense of better accuracy, when in fact just marking the waypoint at a time with an optimal satellite configuration can improve your accuracy much more.

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I think the point that Anders was trying to make was that averaging can give you a false sense of better accuracy, when in fact just marking the waypoint at a time with an optimal satellite configuration can improve your accuracy much more.

 

Except the Garmin unit ALSO display a continual estimate of the averaged accuracy. This lets you know if the averaging is making things better or worse. It works very well.

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I think the point that Anders was trying to make was that averaging can give you a false sense of better accuracy, when in fact just marking the waypoint at a time with an optimal satellite configuration can improve your accuracy much more.

 

Except the Garmin unit ALSO display a continual estimate of the averaged accuracy. This lets you know if the averaging is making things better or worse. It works very well.

Yes, I've used the function myself and agree that it's useful and should be included in the Colorado. There's a funny (confusing) thing about that function, though. Averaging should never make the accuracy worse (the average should be converging on the true location as more samples are collected), but it may make the precision worse, in the near term (if the reported EPE is increasing while you're averaging).

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All I was saying is that I accept the unit as it has been advertised by the manufacturer. Does it live up to what was promised?? to me the answer is "YES" with the exception of ability to mark Geocaches as found on the Calendar. That was a HUGE oversight.

 

Am I happy with the unit - YES. Not making any excuses for anybody - just trying to give a differing opinion.

A counterpoint.

 

There is far too much being made of some issues based on my experience. I can carry my caching data with me without a PDA and that makes me glad I bought it. It leads me to caches and has a large colorful clear display - I like that. It gives accurate readings and allows me to make use of the memory. Transfers are easy and quick. The unit startup time isn't fast but acceptable at just over 1 minute with 1000 waypoints and associated GPX file.

 

If you accept it for what it is - not what you want it to be. It is a fine geocaching GPS - I would recommend it to anybody with the budget to buy it.

 

That's just one persons humble opinion.

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Echoing sentiments above...

 

I'm not making any excuses, or rationalizations, or dismissing that there are, in fact, some issues with the Colorado. As recounted in another post, my early 60CS, AND 60CSx, both had a variety of flaws - some, perhaps, more significant than any we've seen in the Colorado: Anyone remember the lockup when switching between follow road and off-road navigation? 100% reproducible, and I still remember the manual work-around I had to follow to keep from hitting that nasty bug.

 

Regardless - I was happy to have the new features and functionality the unit provided. And this is now how I feel about the Colorado: Not having to carry my Palm to have all the cache data at my fingertips? A huge benefit, in my book.

 

So - I'm a satisfied customer - and, if I had it to do all over, I'd buy the Colorado again. In the first week I had the unit, the first firmware upgrade was released - and I'm confident that Garmin will continue to chip away at the list.

 

Just through these forums and the support of fellow cachers, I've been able to learn (and share) enough about the Colorado to make it a useful, and viable geocaching and navigational tool. I look forward to the ongoing refinement and feature introductions, and to providing my feedback to Garmin to help influence the prioritization of of the fixes/enhancements.

 

Alright then -- let me have it!

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I think the point that Anders was trying to make was that averaging can give you a false sense of better accuracy, when in fact just marking the waypoint at a time with an optimal satellite configuration can improve your accuracy much more.

 

Except the Garmin unit ALSO display a continual estimate of the averaged accuracy. This lets you know if the averaging is making things better or worse. It works very well.

Yes, I've used the function myself and agree that it's useful and should be included in the Colorado. There's a funny (confusing) thing about that function, though. Averaging should never make the accuracy worse (the average should be converging on the true location as more samples are collected), but it may make the precision worse, in the near term (if the reported EPE is increasing while you're averaging).

Hopefully those who have indeed studied statistics will also know that it's not the same thing when the errors in the observations are uncorrelated, as it is when reading GPS data. Here, the correlation is evident. In an uncorrelated environment, the rate of improvement is proportional to the square root of the number of samples, but in the GPS world, that's not 100% true.

 

Those who know anything about GIS and professional GPS use will also know that satellite constellation prediction software is a valuable tool for knowing when the best results can be obtained.

 

Some posters above (yogazoo, CowboyPapa) seem not to be aware of this. The problem in threads like this one is that it often gets very infected, focusing on whether a certain feature must be in the Colorado or not, so that noone can actually open their eyes to any other information, which may make them a smarter GPS user in the future.

 

Now, please, I'm not trying to tell you that averaging is bad. I'm trying to tell you that knowing what you are doing can often outperform the advantage of a function like averaging. Knowledge gives you an advantage. Knowing that averaging can actually make things worse, if you start sampling when HDOP is increasing, is beneficiary.

Knowing that when marking a position with the best precision, accuracy can be improved by using satellite prediction software, is beneficiary.

Knowing that bringing a telescopic rod, perhaps five meters long when extended, where you put a metallic plate, about 120 mm in diameter, on top and an external antenna on the plate, can give you a lot more in position accuracy than averaging a few readings, is beneficiary.

Knowing that an antenna surrounded by choke rings is even better is probably a bit overkill in this context, but knowing that, is beneficiary.

Knowing that due to the nature of the GPS system, and the correlation of errors to satellite constellation, averaging in the range of an hour may be needed to get good data, is beneficiary.

 

As English isn't my native language, I'd like an explanation of what's the difference between accuracy and precision in the post by SiliconFiend above. Are you talking about difference from actual position in one case, but variance in the other?

Edited by apersson850

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I'll summerize the above by aperson:

 

Averaging bad data from a poor spread of satellites just averages a poor position. A single reading from a good spread of satellites is often better. Averaging that "good" position makes it even better yet.

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I'll summerize the above by aperson:

 

Averaging bad data from a poor spread of satellites just averages a poor position. A single reading from a good spread of satellites is often better. Averaging that "good" position makes it even better yet.

 

Judging by the Colorados track record so far. I think averaging would be a very good thing. ;) Buy hey. When you cant read the screen anyways because the batteries died due to constantly having the backlight on full bore , no big deal. ;)

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The eXplorist line didn't do averaging, and I kinda missed it, but I really didn't fret much over it.

I read a while back that the eXplorist automatically averages. That's why it is important to keep the GPSr at the cache location for several minutes when placing a cache. While the eXplorist is stationary, it is averaging. I wonder if the Colorado is automatically averaging. I doubt it though, as Garmin has for a long while had an explicit choice to average when marking a waypoint.

 

Those who know anything about GIS and professional GPS use will also know that satellite constellation prediction software is a valuable tool for knowing when the best results can be obtained.

 

<snip>

 

As English isn't my native language, I'd like an explanation of what's the difference between accuracy and precision in the post by SiliconFiend above. Are you talking about difference from actual position in one case, but variance in the other?

One example of a program that shows future satellite constellations and DOP is Trimble Planning, for those who don't know about it.

 

As for accuracy and precision, accuracy refers to how close an observation is to reality. For example, if the temperature outside is 12C and your thermometer reads 20C, your thermometer is not accurate. If your thermometer reads 20.00036C, it is precise (can more precisely read the temperature to more decimal places) but not accurate.

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I see. What you call "precision" I call "resolution". To me, high precision is the same as good accuracy. It's easy to get the semantics mixed up, when you try to translate a word in one language to what you think it corresponds to in another. Doesn't matter in daily speech, but when it gets more scientific, it can make quite a difference.

 

Averaging bad data from a poor spread of satellites just averages a poor position. A single reading from a good spread of satellites is often better. Averaging that "good" position makes it even better yet.
Perfect summary! Now add to that that without any of these satellite geometry prediction programs at hand, it's very difficult to know, when out there, if you are at a position when the geometry is good or bad, and even more difficult to determine if it's improving or getting worse. The last part is important to know, so you can make a clever guess about whether you should wait and average for a longer time, or try to get out of there quickly, before it gets even worse.

 

Averaging can be good, but to use it efficiently, you got to understand what you are up against.

 

I hope I've shed some light on this now, for someone, who perhaps hadn't thought about this before.

 

Here's another prediction software from Leica Geosystems.

Edited by apersson850

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I see. What you call "precision" I call "resolution". To me, high precision is the same as good accuracy. It's easy to get the semantics mixed up, when you try to translate a word in one language to what you think it corresponds to in another. Doesn't matter in daily speech, but when it gets more scientific, it can make quite a difference.

 

Averaging bad data from a poor spread of satellites just averages a poor position. A single reading from a good spread of satellites is often better. Averaging that "good" position makes it even better yet.
Perfect summary! Now add to that that without any of these satellite geometry prediction programs at hand, it's very difficult to know, when out there, if you are at a position when the geometry is good or bad, and even more difficult to determine if it's improving or getting worse. The last part is important to know, so you can make a clever guess about whether you should wait and average for a longer time, or try to get out of there quickly, before it gets even worse.

 

Averaging can be good, but to use it efficiently, you got to understand what you are up against.

 

I hope I've shed some light on this now, for someone, who perhaps hadn't thought about this before.

 

Here's another prediction software from Leica Geosystems.

 

Thanks for the science lesson. Unfortunately, 99% of cachers do not cache only when the satellites are in a optimal positions. Some people prefer to sleep at 3:00am. I know, that's just plain nuts. Just from my experience when caching, averaged coords seem to be more accurate but then again it may have been that the initial coords were just very bad. A very seasoned cacher once told me that the best coords are obtained from samples taken on different days, at different times, and under different conditions. Some GPSr's hold a better lock, some GPSr's are more accurate, some people don't know how to use their GPSr's. Since most of us cache under the same conditions in which the caches are placed (non-optimal satellite geometry), the ability to average coords with your handheld GPSr will continue to be a hot topic.

Edited by 3 Hawks

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All what you say in your comment is true, except for what the seasoned cacher told you.

So to the average man, averaging (pun intended) may be the proper tool. Or at least it will make him feel like he's on top of it, because he's doing something more than just taking one sample of the positon calculation. He's happily unaware of that averaging now may be inferior to a snapshot two hours later.

 

One reason that averaged positions, taken over a fairly short time base, usually are better, is that they reduce the impact of occasional spurious readings, where the position happens to jump away one second, then come back the next. If that happens to occur when you press the button to save a waypoint, then you are out of luck. When averaging for two minutes, you are only out of 1/120th of luck, assuming it happened only once.

 

If you meet the seasoned cacher again, you now know enough to be able to tell him that you don't at all need to go back during different times of the day to get a good result. If you do that, you'll still not know which results were more reliable than others. Instead use the prediction software and go there once, at the optimal time of the day, and you get the best result in one operation.

 

If you are asleep at 3:00, then chances are good that you are awake at 14:55, which is when about the same pattern reappears on the sky.

Edited by apersson850

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Thanks for all of the valuable input on obtaining the highest amount of accuracy and precision from my GPS. I would like to make three points.

 

1) To suggest I plan my work day around optimal satellite arrays is rediculous. I have about 1000 things ahead of that on my priority list.

 

2) Using satellite array status to increase data accuracy sounds like another work-around/pain in the %#@ until the averaging function is put back in the works.

 

3) We aren't looking to get within centemeters, or even feet through averaging. What our goal is, and why we average in the first place, is to cut back on aberrant data that can occur in a single snapshot.

 

While averaging on a Garmin, the GPS accuracy figure and number of data samples are used in its calculation. I have seen accuracy decrease initially before going back up. Sure, averaging a dumb sample with random error would be less accurate, however the error is not uncorrelated as Anders suggests and an error value is assigned and used with each data snapshot in the calculation.

 

Please Garmin, just give us the average option.

Edited by yogazoo

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If you are asleep at 3:00, then chances are good that you are awake at 14:55, which is when about the same pattern reappears on the sky.

 

Work?? Kids?? Wife??? Other obligations??? Bad weather??? I understand what you are saying, but I only agree to a point. I tend to cache when the window of opportunity presents, not when the stars and satellites are alligned.

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<snip>

As English isn't my native language, I'd like an explanation of what's the difference between accuracy and precision in the post by SiliconFiend above. Are you talking about difference from actual position in one case, but variance in the other?

<snip>

As for accuracy and precision, accuracy refers to how close an observation is to reality. For example, if the temperature outside is 12C and your thermometer reads 20C, your thermometer is not accurate. If your thermometer reads 20.00036C, it is precise (can more precisely read the temperature to more decimal places) but not accurate.

You're right about accuracy and close about precision. Precision has more to do with repeatability, although resolution is part of it. Some examples from target shooting (or darts, if you wish): Scatter of marks around the bullseye, in a 5-inch circle: Good accuracy but poor precision. Cluster of marks within a 1-inch circle, offset 3 inches from the bullseye: Good precision but poor accuracy.

 

Generally, over a short time frame, GPS receivers have better precision than they do accuracy, due to systemic errors (some of which WAAS helps to correct).

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[ I tend to cache when the window of opportunity presents, not when the stars and satellites are alligned.

 

In that case, you have totally eliminated being able to blame it (poor accuracy, repeatability etc) on ANY GPSr, and you'll have to accept the fact that "What you sees, is what you get"

 

........or maybe you could just totally re-invent the GPS satellite system and possibly eliminate the ionospheric (sp?) influences also.

 

The more accuracy you expect, the more you have to "follow the rules" or "work within the system" or "do your part" to attain that accuracy.

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[ I tend to cache when the window of opportunity presents, not when the stars and satellites are alligned.

 

In that case, you have totally eliminated being able to blame it (poor accuracy, repeatability etc) on ANY GPSr, and you'll have to accept the fact that "What you sees, is what you get"

 

........or maybe you could just totally re-invent the GPS satellite system and possibly eliminate the ionospheric (sp?) influences also.

 

The more accuracy you expect, the more you have to "follow the rules" or "work within the system" or "do your part" to attain that accuracy.

 

Yep.....and that is why people "do their part" to average coords since they can't change the satellite formations, orbits, and schedules. I don't think I've ever met a geocacher that schedules placement or caching times on the optimal positions of the satellites. Anyone that does, has far too much time on their hands. In a perfect world, you would not need to average coords because they would all be dead on all of the time.

 

I'm, not so much concerned about my accuracy since I will continue to average for the benefit of myself and others. What do you mean by "do your part?"

 

What do you mean by "follow the rules" and "work withing the system?" To what rules and system do you refer? The long held practice of averaging coords for the benefit of others or only caching when the satellites are in perfect formation? In the case of the later, that would only be of benefit if the person hiding the cache hid it under the same ideal satellite configuration.

 

Was there a point to your arguement I missed or was it only to pander and inflame??

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The eXplorist line didn't do averaging, and I kinda missed it, but I really didn't fret much over it.

I read a while back that the eXplorist automatically averages. That's why it is important to keep the GPSr at the cache location for several minutes when placing a cache. While the eXplorist is stationary, it is averaging. I wonder if the Colorado is automatically averaging. I doubt it though, as Garmin has for a long while had an explicit choice to average when marking a waypoint.

That may be true, but one of the guys who worked on the eXplorist software told me explicitly that it didn't. He seemed to know what he was talking about.

 

--Marky

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Do your part= use ALL (or at least those within reason) the available tools at your disposal to attain the best accuracy possible.

Follow the rules & Work within the system were intended to be "figures of speech" meaning that users need to familiarize and absorb as much knowledge as possible on the subject (GPS) and some of the inherrent inaccuracies of consumer grade units.

There are user habits that can be developed (or in some cases should be eliminated) that can reduce the effects of those inaccuracies. (Averaging can be one of them and another is the Satellite Availability program. There's another one of those on Trimble's site)

It's not that you can only cache at certain times. Look at it from the perspective that you can easily identify a certain specific time on a specific day that you can tell beforehand that your unit is going to be inaccurate........guaranteed!

All of this is only important if the original intent is to be as accurate and as repeatable as possible

Sorry, didn't mean to "Wind your Spring" (That's another F.O.S.)

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Do your part= use ALL (or at least those within reason) the available tools at your disposal to attain the best accuracy possible.

Follow the rules & Work within the system were intended to be "figures of speech" meaning that users need to familiarize and absorb as much knowledge as possible on the subject (GPS) and some of the inherrent inaccuracies of consumer grade units.

There are user habits that can be developed (or in some cases should be eliminated) that can reduce the effects of those inaccuracies. (Averaging can be one of them and another is the Satellite Availability program. There's another one of those on Trimble's site)

It's not that you can only cache at certain times. Look at it from the perspective that you can easily identify a certain specific time on a specific day that you can tell beforehand that your unit is going to be inaccurate........guaranteed!

All of this is only important if the original intent is to be as accurate and as repeatable as possible

Sorry, didn't mean to "Wind your Spring" (That's another F.O.S.)

 

That's OK.....It doesn't take much to "wind my spring," but I quickly return to my normal irrational self. I agree that this is only important if the intent is to be as accurate and as repeatable as possible, but that also applies to average use, under average conditions, that may or may not be optimal conditions and times of day. Just because I cache during an window of optimized reception, does not mean the person who placed a cache did the same thing. I would hope that cacher at least took samples, averaged the readings to eliminate wild readings, and tested the result on another day at another time.

 

OK....I've got that out of my system.

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That may be true, but one of the guys who worked on the eXplorist software told me explicitly that it didn't. He seemed to know what he was talking about.

 

--Marky

--Marky :

Is that guy still around? There's a few (will be more as more units eventually have to do a 'reset')

Meridian/eXplorist folks that would like to have some fruitful discourse with him regarding WAAS,

or lack thereof.

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That may be true, but one of the guys who worked on the eXplorist software told me explicitly that it didn't. He seemed to know what he was talking about.

 

--Marky

--Marky :

Is that guy still around? There's a few (will be more as more units eventually have to do a 'reset')

Meridian/eXplorist folks that would like to have some fruitful discourse with him regarding WAAS,

or lack thereof.

Funny you ask... when I emailed him about my Triton woes, the email bounced, so I guess he's not with Magellan anymore. Bummer, it was nice talking to someone on the inside now and then. I even got to see a bunch of suggestions I made show up in a firmware update for the eXplorist. That's always a satisfying feeling. :D

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