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Grasscatcher

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Posts posted by Grasscatcher

  1. I REALLY don't understand why this pops up now and then.

    Oregons screens ARE VERY READABLE in sunlight, the more light the better readable, backlight is totally unnecessary in the sun, only in darker places, or the shadow.

     

    The fact that very often these complains always talk about use of backlight in the sun, makes me wonder.

     

    Yes,........... if you can turn and tilt to get the screen in the best viewable position. Generally not too big of a problem while using GPS functions.

    However, just try to aim and frame a pic in some other direction (than the above viewable direction). Quite often, that is an impossible task due to the screen being totally unreadable while pointed in the direction you need to, to take a picture. Requires screen and/or eyes to be shaded by hat or hand held shield of some type.

    A real PITB.

  2. With the new 2.6 upgrade for the 550t, Garmin GREATLY improved the tracklogging accuracy issues.

     

    I said I didn't know what the problem was..........apparently they DID know..... and did something about it!

     

    Must have been in the "improved along road routing performance" part of the update.

  3. The problem is the ceramic patch antenna. Not soft or firm ware.

    That's not entirely true. The DeLorme PN-40 uses the same chipset and a similar patch antenna. Originally, the device obtained and used WAAS corrections very rarely unless you were located far enough south for the WAAS satellites (which are in equatorial orbit) to be well above your local horizon. Eventually DeLorme shipped a chipset firmware update which much improved the situation. Mind you, it is still much worse than my Garmin Colorado, which uses WAAS corrections all the time. Nevertheless, the problem was amenable to a (chipset) firmware correction. I would imagine that the same is true of the OR.

     

    That said, WAAS corrects for second order effects like ionospheric disturbances. Satellite geometry is still the biggest factor in accuracy at any given time and place.

     

    Just to be clear, these comments refer to a Garmin Oregon 550t.

     

    Is it software/firmware? .........I don't know.

     

    Is it senstivity to multipath error?.....I don't know.

     

    Is it antenna?..............I don't know.

     

    Is it Garmin vs DeLorme?..........I don't know.

     

    HOWEVER, BOTH units and COMPANIES have REAL problems.

     

    Here are my personal experiences and opinions. I enjoy Hiking, ATVing, Snowmobiling, and for the past 15+ years (remember Selective Availability?) I have GPS'd and mapped almost every trail I have traveled.

    That equates to several thousand miles under almost every condition. Thru 7 GPSs I have evolved to using a Garmin Map76CSx. Why? Because that is what produces the best quality tracks overall, under all conditions. So, yes, I am 125% a Garmin fan (read on) because, ignoring all the Hype and BS, that is what works to date.

     

    And, since I am always open to something better, as soon as the PN-40 came out, I got one thru REI and tried it. Under wide open ideal conditions, it did OK, but as soon as conditions started to become marginal (read canopy or canyons) its tracklogging could not even repeat with itself. Multiple out and back hikes on a single track trail produced tracklogging variations of 100+ feet, same day, same conditions. That's only comaparing it to itself, not the 76CSx (which was "hands down " more consistent). Needless to say, I no longer own a PN-40.

     

    Next in line is the Oregon 550t. I will start off by saying that if this unit is supposed to be Garmin's top of the line handheld, Garmin has problems. Screen visibility in sunlight ( like a cheap camera LCD) and WAAS reception both suck! Everything else is dumbutt simple.

     

    I like not having to carry a separate camera because the auto geotagging is great.( Also, the pics are surprisingly good) However, NOW I would have to carry a separate GPS if I wanted accurately logged trails. So, what have I gained? NADA.........

     

    Here's a non-scientific, real world experiment. A 5 mile narrow single track loop trail in deep canyon country.

     

    First Trip: carried 2 GPSs

    Map 76CSx on right shoulder with X ant on top of backpack, Tracklogging Auto, More often logging interval, WAAS ON.

    Oregon 550t on left shoulder Logging settings same (as 76) but WAAS OFF.

    Trip produced 3 tracks, 76 CSxActive Log, 76CSx saved track (500 tps) and 550t track

     

    Second Trip: carried 3 GPSs.....same single track trail as before.

    Map 76 CSx on right shoulder, without X ant, same logging settings as before, and WAAS ON

    Oregon 550t on left shoulder, same logging settings but with WAAS ON

    Added: Map 76CS (non x-older non high sensitivity chip) hooked to X ant. GPS in pack and X ant on top of pack.

    Trip produced 4 tracks, CSx active log, CSx saved, CS active log, and 550t track.

     

    End results? The Oregon produced the two "stand out sorriest" of all seven tracks. Under Ideal conditions, all seven tracks are acceptable but, as soon as conditions deteriorate, the Oregon falls on it's face, to varying degrees. Between trips, it remembered the "areas" that it didn't like, and really did think that it was "off over there" on the other trip........somewhere.......but couldn't remember exactly how far within 50-100+ feet in the "bad areas"....while the 76CSx trudged consistently and accurately along.

     

    My overall conclusion is that both Garmin & Delorme have spent too much time concentrating on "games" and not enough on GPS accuracy and capabilities. Neither of their latest units are serious tools....just bad jokes.

  4. Me thinks too many people are concerned with pictures not acual GPS accuracy.........navigate to a Benchmark with known and "adjusted" (not scaled) coordinates. Those coordinates are established closer than any consumer grade unit can calculate.

     

    After NUMEROUS BM (with adjusted coordinates) checks, I have YET to do so and have my unit tell me that I am off more than 1-2 meters. (I use UTM)......whether or not it says I have a WAAS lock or can see the "D"s on the satellite bars, and regardless what the EPE guess is.

     

    EPE is a calculated guesstimate, swag, unreliable comparison even within the same brand. There is absolutely no direct connection to accuracy.

     

    If WAAS is available in your area, set your unit to receive it and forget it.

     

    Determining the accuracy of your unit using "Cache" coordinates is impossible.

  5. Let me see if I've got this straight.......

    At some time in the future you are going to send back to the manufacturer a unit that works "perfectly" to have it repaired ???..... to bring it up to like new condition and standards....that don't lock as quickly, that don't acquire WAAS as regularly, or calculate routes as quickly, or possibly maintain sat lock as well????????????

    Is this a DUH ! moment or what?

    Sounds to me like what you really need to do is leave your SE laying in the road in traffic for a while!

     

    (Sorry, the Devil made me do it)

  6. Just personal opinion, but I think Searching UT may have described what the problem is, and Redwoods Mtn Biker may be "on" to the solution..........

     

    Georeferencing smaller "chunks" may correct the visible errors, at least on smaller maps.

     

    I know that while hiking and mapping the actual trails, trail conditions and common sense have (at least so far) kept me from taking any (single) minus 500 ft elevation steps. Maps can only tell you so much.......

  7. I'm buy no means an expert on using Google Earth so maybe someone else can elaborate more on this issue. When I import an overlay into GE if I don't first put the cursor on the very bottom center part of the eye in the navigation bar, I have displayed in the top right of my screen, and click on it, the aerial view is not straight down and the view is slanted just slightly thus making my overlay so that it will not overlay perfectly either in N to S or E to W depending on how the aerial image in GE is slanted.

     

    So I always make sure my GE sat. image is being viewed directly straight down before importing any overlays.

     

    EAP,

    Thanks for the suggestions.

    Just for grins, I deleted everything and re-imported my trail file again. This time, I was sure aerial view was looking "straight down" per your instructions.....no changes from what I had before.

    I'm beginning to think that the georeferencing in Google Earth imagery is strictly for the "Oh looky, there's my house" crowd.......

     

    Waypoints saved while on the track are shown "on the track" and have correct coordinates, but if you pick the visible point (a trail intersection) on the "picture" and get the coordinates for that point, then those are incorrect.

  8. I've got a number of very accurately GPSd tracks that, when viewed in Expert GPS or in USA Photomaps, are "dead on" the visible trail in the image.

     

    HOWEVER, when imported into and viewed in Google Earth, the very same tracks show to have a position "shift" to the North.....(amount in the range of 30-40 ft). Appears very visibly off/inaccurate.

     

    Area is in the Colo Natl Mon West of Grand Junction. Datum is NAD83/WGS84. "Clamped to ground" in GE.

     

    What implications does this have when georeferencing imagery in GE to put on a GPS? Or, do I have a setting wrong somewhere?

     

    Any ideas?

  9. Segler999,

    "1. If you save a tracklog within the gpsr deliberately it will be nearly useless. So, don't ever save a tracklog within the gpsr. Never."

     

    Isn't that bad advise?....what if the user wants to use the trackback function?

    Without the track saved in internal memory, and trackback, the only way to follow the same route back is visually following the breadcrumb trail on the screen.

    What if the user wants to use that track to follow in the future? Even an active log track or card gpx file ,when reinstalled /reloaded into the GPS, is reduced to 500 TP and data stripped. (unless renamed as Active Log when reloaded)

    It's not a one size fits all. Both types (saved & card gpx) are equally useful., but for totally different applications. Saved files for use on the unit itself, and active log or card gpx files for use on the PC with ALL the data accessible for geotagging, more accurate mapping, etc.

  10. SS,

    The best of all situations is to ALWAYS log to the card and OCCASIONALLY transfer those gpx files to your PC. You can sort through those at your leisure to determine which to keep and which to delete.

     

    I went back and read your OP again.

     

    Anytime you have your unit on, it is logging info to the active log, as seen as the breadcrumb track on your screen. It continues day to day to day up until it gets up to 10,000 trackpoints. Depending on how your options are set determines what it does at that point.

    It is logging data to the internal memory....not saving a gpx file to the memory.

     

    Logging tracks to the card is a separate, different action. Each calendar day(when the GPS is on) your unit starts a new gpx file (named by date) on the card. Also, in addition, everytime you turn your unit off and back on it starts a new gpx file on the card, and also when you "clear track log" a new gpx file is started on the card.

     

    GPX files on the card are only accessible through your PC.

  11. SS,

    I'll see if I can help.......

     

    You are SOL on using yesterday's "saved" track for geotagging. Reason? because,you have cleared the memory and,when you "save" a track to internal memory, as Red90 said, the unit strips time,elevation, date away. (and the time of the trackpoint is what would be used for geotagging)

     

    Since you have not cleared TODAY's memory, download today's trip and what you will see in Mapsource is "two" tracks. One will be named "Active Log" and the other will have whatever name it was named when you saved it.

     

    "Active Log" will have ALL the data whereas the "saved" track will "look" the same when displayed, but will have time, elevation, date missing. Look at "track properties" on each of those two files, compare which columns are present/or missing.

     

    When you log tracks to the card, it logs ALL the data there also, so for geotagging, you MUST use either the "Card file" or the Active Log .

     

    When you "Clear Track Log" on your unit, what you are doing is deleting the Active Log from memory,( what you see as the breadcrumb trail on the GPS screen). Clearing the track log DOES NOT delete anything from the card, if you have been logging to the card also.

     

    Hope this helps.

  12. ............ There is a thought out there that increased sensitivity in canyons makes the GPSr more receptive to multipath error.

    Cheers,

    Jim

     

    In my actual personal experience, I have found the exact opposite to be true when using an X antenna.....less problems with multipath errors and fewer problems with "random points". The user still has the advantage of the "high sensitivity" chipset while the high mounting of the X antenna (top of hat,helmet,cap) eliminates or reduces signal blockage.

     

    Granted, my experience is not a scientifically valid test. I'm only basing my opinion on actual results of numerous past "out and back" tracks under difficult conditions that overlay each other extremely closely.

     

    When viewing tracks overlayed on 1:24000 USGS maps, the tracks are a "perfect" match. It's only when viewed "zoomed in" to the point where the map contour lines start to become "pixelated" , that you can even tell that there are multiple tracks. That's saying that the tracks are probably more accurate than the map, which is "plenty close enough" for me and "Government Work".

     

    As stated above, there are places where reception is impossible......at least for me....so far.....

  13. Seldom sn,

    You are "Right On" with your opinion of external antenna improving reception accuracy in difficult conditions! Don't let anyone talk you out of it.

     

    The GPS Outfitter case workswell and has places for extra batteries and used batteries. Can be placed on your belt or carried on a shoulder strap like a camera.

     

    Velcro'd on a cap bill, or on top of a hat,helmet, etc works well. Any of those places are better than on a pack strap or in a pack because of signal blockage by your head,or body, etc.

     

    A couple of other suggestions........ keep moving while logging, and I have found that using track logging method "Auto" and track logging interval "more often" or "most often" works best.

     

    Trimble Planning (free) software can help immensely to choose the absolute best time (regarding satellite geometry) to map a really difficult location.

     

    and....you will find that there are still SOME places (slot canyons) that are impossible.

  14.  

    What that means is less screen visibility (with no external power) and very short battery life due to exposure to the cold......unless an external antenna is used, where the actual GPS can be kept inside the users jacket and only the external antenna is exposed. The Oregon does NOT have external antenna capabilities whereas the Colorado series DOES.

     

     

    .. like I said in my post, I keep my Vista Cx in an inside coat pocket while snowmobiling and it seems to keep a great signal lock through my coat. At the end of the day I almost always have a nice unbroken plot trail of my days travels. Do you find you need an external antenna when keeping your GPSr inside your coat?

     

    After mapping several thousand miles of hiking, ATV, Snowmobile trails I find that using a high mounted (velcro'd on top of cap or helmet) external antenna regularly results in a higher quality track being recorded, especially in less than ideal conditions.(ie heavy canopy)

    It's also the main reason I do not own an ETrex series, an Oregon 550t, or a PN series.

    An external antenna also helps to reduce the "dreaded" undesirable random points logged by some of the new high sensitivity chipsets.

     

    If you don't care about obtaining the highest quality track possible for reproduction, and are only interested in having a breadcrumb trail to follow back, then the X antenna is not necessary. You can carry it in your coat or in the top of your pack and it will generally maintain an acceptable "lock", but will have some discrepancies due to signal blocking and/or multipath errors.

     

    Just personal experience and opinion.

  15. For use on a snowmobile, the larger screen Oregons and Colorados are better. When plugging into external power their screens are much brighter than other units. If to be used for caching, they are substantially better than the old units.

     

    I would suggest an Oregon 300.

     

    Free maps including topographic maps and Snowmobile trails are here: http://www.gpsfiledepot.com/maps/state/mi

     

    Red 90,

     

    No arguments, just comments.

     

    Many, (most?) snowmobiles don't have an easily available external power source for "plugging into".

    Mine does, to run my Map76CSx and a ham radio for APRS operation, but it took some extensive "hard wiring" to facilitate.

     

    What that means is less screen visibility (with no external power) and very short battery life due to exposure to the cold......unless an external antenna is used, where the actual GPS can be kept inside the users jacket and only the external antenna is exposed. The Oregon does NOT have external antenna capabilities whereas the Colorado series DOES.

     

    All this is just saying that units with external antenna capabilities (60 series,76 series, Colorado series) have a slight "leg up" for extreme cold weather use. (but of course, no paperless capabilities on some of those)

     

    While trail mapping, I run a Map 76CSx with external antenna. Sometimes hooked up to external power, sometimes not, depending on duration of the exercise.

  16. When I enter a new waypoint on my 76CSx after deleting all previous waypoints, why doesn't it begin at 1 again? For example, the next number is 028. How do I get it to begin again at 1? I have deleted all previous waypoints! What am I missing? :D

     

    Here's more information... In case you just want to delete isolated numbers from your waypoint list.

     

    Example Waypoint List: 1,2,4,5,6,7,9,10,(consecutive to 25) 26,29, etc, with several missing numbers between there and let's say 65.

     

    The next waypoint you want to save would normally be numbered "066". Before you "save" it with that number, toggle up to and highlight the 066. Use the keyboard and change the 066 to whatever is your lowest/first in the list "missing" or deleted number. ( 003 in the sequence above)

    Save it with that number.

    With the sequence above, the next waypoints you save will be numbered 008 ( the next number missing from the list), then 027, then 028, etc , thus "catching" only all the missing numbers thru 065 ( in the above example), then continuing on with 66,67,68 in the standard sequence.

     

    User must manually identify/change to the desired point in the list and it must be a missing number. Otherwise, you will get an error message "waypoint already exists".

  17. Every few months, I just copy all the GPX files from the card to a "Memory Card" folder on my computer, and delete them from the GPS. Then at my leisure I can view each one and delete the unimportant ones and retain the others. Never have I lost any data or had a file limit problem.

    Your GPS starts a new GPX file every calendar day, every time you turn it from off to on, and every time you "clear track log", so you can see how the number of files can add up .

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