Re: GPS Problems? | Forum — The Modern Antiquarian

T

tiompan Feb 17, 2008 11:20:59

Replying to gjrk

gjrk wrote:

Thanks very much for your prompt replies 4W and Tiompan. I suppose it must be the heavily drilled respect for authority in me, but I found it difficult to believe that the Inventory could be wrong!
To check the GPS readings I'd have to compare them with someone else's and I just had a quick glance at your website 4W. I'd rechecked Drombeg yesterday (It's a handy place for my small boy to play around, except for that mound of rusty offerings in the centre) and my circle reading corresponds with your Fulacht Fiadh?
Sorry for getting so bloody obsessive about a few metres but I'm trying to sort something out.
g

Gjrk , where about's in Ireland do you live ? , I'll see if there is a pillar nearby where you can check your gps .

T

tiompan Feb 17, 2008 11:34:42

Replying to gjrk

gjrk wrote:

Thanks very much for your prompt replies 4W and Tiompan. I suppose it must be the heavily drilled respect for authority in me, but I found it difficult to believe that the Inventory could be wrong!

Sorry for getting so bloody obsessive about a few metres but I'm trying to sort something out.
g

I would expect the Inventory to be wrong in most cases and only accurate if a relatively recent reading .I have just commented on Britarch about something similar , true north on excavation reports , mostly way out , a classic Irish example is the O' Kelly Newgrange drawing , if the builders had got it that wrong you'd still be waiting for the sun to enter the passage . Sounds like an astro doodah your intersted ,any clues ?

F

FourWinds Feb 17, 2008 19:24:52

Replying to gjrk

gjrk wrote:

Thanks very much for your prompt replies 4W and Tiompan. I suppose it must be the heavily drilled respect for authority in me, but I found it difficult to believe that the Inventory could be wrong!
To check the GPS readings I'd have to compare them with someone else's and I just had a quick glance at your website 4W. I'd rechecked Drombeg yesterday (It's a handy place for my small boy to play around, except for that mound of rusty offerings in the centre) and my circle reading corresponds with your Fulacht Fiadh?
Sorry for getting so bloody obsessive about a few metres but I'm trying to sort something out.
g

F

FourWinds Feb 17, 2008 19:28:01

Replying to gjrk

gjrk wrote:

Thanks very much for your prompt replies 4W and Tiompan. I suppose it must be the heavily drilled respect for authority in me, but I found it difficult to believe that the Inventory could be wrong!
To check the GPS readings I'd have to compare them with someone else's and I just had a quick glance at your website 4W. I'd rechecked Drombeg yesterday (It's a handy place for my small boy to play around, except for that mound of rusty offerings in the centre) and my circle reading corresponds with your Fulacht Fiadh?
Sorry for getting so bloody obsessive about a few metres but I'm trying to sort something out.
g

There could be a couple of factors here. I used to take a reading as soon as I reached a site. In most instances the GPS thinks you're still moving and so can add a few metres. Then, if my reading was 10m out due to the inaccuracy of the GPS and your reading is 10m out then that could give a difference of 20m between readings. Now I always put my GPS down while I'm taking photos and then take a reading as I leave. I hope this gives a more stable and accurate reading.