It depends on the actual phone manufacturer unfortunately not the operating system, just like with the normal camera manufacturers. I think we did a test with phones and some worked and others did not although this was some years ago.
It might be a good time now for another test but it might take a bit of organising as we will want as many phones as possible but with real observations and will need to ask certain questions to make sure it is the phone/image that is putting in the data and not that the browser is picking up your current location.
One of the location error people that I identified last year seemed to be assuming the phone had given the correct location to the observation, from the location name, but in reality the location entered for all observations was their home (I assume).
Thanks
I used by camera’s EXIF yesterday, it overrode the Chome location, which is back this morning.
To be honest, as I am not travelling far, I am happy with it rememberng where I live. I always check location carefully and often add Location notes - few peole do.
I think it’s time to remind people that location matters
Those who have a Hide precise location tick permanently, might prefer to change - few people seem to know of that tick.
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We now know, from slightly bitter experience here https://www.ispotnature.org/communities/uk-and-ireland/view/project/793040/ (check the Map) that Location Notes are potentially useful
There is a need for a home page Item (panel) that contains essential and useful annoucements. It needs to be current, dynamic and perhaps illustrated, otherwise it will get ignored, do you thnk?
I may have mentioned it before.
This is something I am a bit worried about. It is fine for people to tick this box but I am worried that it sometimes ends up ticked even when you have not ticked it yourself.
I have noticed this has happened on a small number of my posts, the vast majority are either ticked or not depending on what I have done but with a small number it seems they have ended up ticked when I can’t see any reason for me doing it. It is possible the mouse ended up in wrong place especially if using phone or something but can’t really think of another reason for this happening.
@miked In the early days of satellite technology we used a Garmin to locate our position on the Cape Peninsula. we would wait for our tracker to identify the best of a number of satellites. Our locations were quite often close to strategic military bases like Simon’s Town Naval Base and the underground base at Silvermine and I was never quite sure if some might have been spy-satellites.
Readings on Table Mountain were quite often way out.
Wondering how accurate some modern devices might be.
I may have commented elsewhere that some of the positions recorded (when I used Gooogle Earth) are no longer as accurately shown on the Google Street View we get on iSpot now.
But then think of the early botanists in Africa who marked locations by comments like ‘the spot where we stopped to outspan the oxen’ ( or something similar) Their herbarium specimens are still of immense value. So, I think, recording details of the subject and describing the location should always be a priority. Just my opinion.
Modern GPS devices claim accuracy to 1 or 2 metres, but they don’t always achieve it. I’ve seen a track of where I’ve been veer off the road and run parallel to it tens of meters away, and there are plants where the location recorded depends on which direction I approach it from. (And I don’t think that the latter is all down to lag.) On the other hand sometimes a 10 figure (1 meter accuracy) British National Grid reading can take me right back to a plant.
In addition to the noise inherent in the GPS system, record locations also have noise resulting on where I’m standing with respect to the plant (and colonies can be several meters across). What I’ve experience is that records of plants are consistent to a few meters, or sometimes up to ten meters or so. I understand that the BSBI prefers 8 figure records, but with 5 meters of a 10 figure reference is more precise that within 10 meters of a 8 figure reference.
This paper discusses accuracy https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/j.2041-210X.2011.00118.x Where are my quadrats? Positional accuracy in fieldwork I wrote it some years ago now but accuracy of consumer grade gps has not improved much since then. You would be very lucky to get 1-2m accuracy without waiting a very long period (because the errors are not random you can’t just do a bit of averaging over a few mins), (3-)5m in the open is more of a standard still.
It is not just about the number of satellites, there are a lot more nationalities available now than when I wrote the paper, but still the professional grade gps mostly relies on the american satellites which have not changed much in number. Others (Chinese, Russians etc) might help if you are in a difficult situation with limited visibility of sky or limited signal strength though. As far as I know still the EU system (Galileo) is not fully functional, that might change the situation regarding accuracy and signal strength when it eventually becomes fully functional.
One thing that as far as I can see is missing that would cause errors is local and continental ground movement.
I have only flicked through the reports.
Peat moves depending on water content and is unlikely to go back to the original position as the dehydration and re-hydration will take place differently. It will tend to move down hill over years.
Continental drift will effect any readings that are taken on a different continent to the owner of the satellites as there headquarters will most likely house there master origin point.
There is no need to burn masses of oil going to an earthquake zone to test my theory.
We just need to find someone who owns accurate laser sights and lives in Scotland. Then locate a couple of OS triangulation markers on either side of Loch Ness and measure them. Wait until there has been a monster wake report and measure them again. Don’t expect more than 1mm of movement as that will easily shift a vast amount of water against the steep underwater crags in the Loch without the micro earthquake being felt.
An interesting and relevant comment but perhaps slipping(!) a little from the topic. I want to be able to provide accurate data about where the plant was when I saw it, rather than where it might have moved to. The EXIF data embedded in photos taken with GPS-enabled devices should generally provide that data so how can I ensure that my device provides the data in an iSpot-friendly format or what can iSpot do to widen the range of formats it accepts?
If there is a recognised standard for encapsulating location data, can anyone provide a reference to this so that I can start to check if my device is compliant?
Previously we tried different libraries and found that they were able to read different devices, settled on one that read a lot of devices. I am not sure how many (if any) other libraries are available at present or if it would be technically possible to use more than one (without loads of extra coding which we can’t do at present).
I could send you the location info from all of your observations if you want to check them.
If you want to look at/check etc the location info in images then I think you can use robogeo program for doing that, there are other programs available.
Once you start getting beyond about 30m accuracy then you have to think about how you are converting between lat long and local grid such as the ordnance survey in UK. This can get quite complex and there are many websites/programs that get it wrong. For example if you read the lat long from your image but want this info in ordnance survey coordinates and you think you have measured the lat long very accurately then you need to use the full accuracy transformation which is available on the ordnance survey website for individual sets of coordinates or they have a third party program that can do this conversion with full accuracy for whole spreadsheets of locations. Earlier hand held gps devices did not use this full accuracy transformation as there was no need as they could not give coordinates accurately enough, I am not sure what the current situation is, you can understand why they did not bother to do this ‘properly’ as they have to handle every local coordinate system worldwide.
You sometimes go back to the same locations, do you have a good app for doing that? On the pro grade dgps we use there is just an arrow that you follow and it goes right to the exact cm and does not flap about much but on the smartphone apps I have tried they jump all over the place so it is very difficult to walk direct to the point even if the phone can get the location to within a few m.
Finding ants
I never buy apps, always use the free version.
W3W uses the rough direction (and jumpy) arrow but counts down in metres. If you stand still it does not ‘say’ anthing. Go past and it will tell you.
I can use any one of three apps for direction. Shown here is the W3W display, it is not difficult to use.
Fine of course for a club moss, my primrose quadrat or marked stone (my ants) but perhaps not for acorns burried by a squirrel - until it is a sapling.
Is the name of the app W3W or what3words or something else.
There are several similar apps on the app store but nothing with that exact name, although google says it is finding results for ‘me’ so it may think I am not interested in certain apps so does not show those ones!
edit, have looked up what3words app and it gets very mixed reviews to say the least, in my quick reading either people say it is very good or quite poor or terrible. Perhaps it would work particularly well in open areas where you make sure the phone is using gps and has a good sky view i.e. not in urban canyon or under forest. I used to use Mobile topographer (the free version) but like so many good free apps that has long since been discontinued and even the payfor version has not been updated recently.
Oh sorry
What 3 Words what3words /// The simplest way to talk about location is internationally recognisedand and used by rescue organisations
type/paste in my location above - beware of making a mistake with the words slamming.showrooms.fallback - this means YOU can find my Club Moss
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I will add a few more references to new Observations
Here is a nicer one for find decay.payout.manifests
It is sandbank with a small outcrop which I check for Saddle Oysters
Now if you are a bit flustered and tell the police that you are at decay.payouts.manifests they will have fun, though they will not be slow in suggesting YOU are wrong. Try it and always take care with W3W locations!
Here’s the App Download the free what3words app | what3words
OK, on the apps front that mobile topographer one I mentioned above now has moved on to mobile topographerGIS which has loads of functions that are useful if you are a surveyor but at a price of £31 per year.
A free one that I have just come across after reading several recent papers about gis on smartphones is GnssLogger App. Loaded this and it gave my location within about 80cm and I am inside a building! There are one or two similar apps that get this high accuracy by getting at the raw gps data (L1 and L5) from all satellite systems and processing separately before combining to give location, it can also log all the information and of course show where the satellites are. The app only works on fairly recent fairly high end phones I think though. not sure if it can take you back to the point well though
OK I have GnnsL in my phone and it detects me in this room beside my PC but appears not to give a Lat.Long or Grid ref, nor has a save button ot go-to button. It seems uncannily accurate and is continuously active
This is good (Grid Ref UK) if you have a camera with you, to record the location but again has no Go-to or save method. I find it particulary useful for location on the iSpot Map because you can type in the whole ref. I often lay my phone beside a find, for a photo
See Location in here
