Map Datum HELP!

[Hunters-5]

So last night I'm manually inputting more caches into the ol' Garmin GPS 12XL and I start checking out some of the settings and options.  Turns out I have the Map Datum set to NAD27, not the default WGS 84.

On Geocaching.com, I check out my Wake Up Neo cache and click the "other conversions" to see that W 089 15.624 converts over to W 089 15.619  Bear in mind I entered the original coordinates as if they were from WGS 84, so I can’t just substitute these numbers as a correction.  The North coordinates remain the same.  Perhaps this explains the 12 meter consistent discrepancy that both H-K and Q&A brought to my attention.  How do I convert .005 to meters to find the distance I was out?

This may also explain why we've had difficulties finding some caches - and not finding others.  Aaarrrggghhhhh!!!

For my active caches, is it practical (and reasonable) to ask that geocachers use the NAD27 datum for their hunt?  As well, the caches I've hidden and not yet submitted will all have coordinates from the NAD27 map datum.  How can I easily and accurately convert these over? 

Any assistance you can provide will be appreciated.

[ChrisDom]

I would suggest that you use your GPS to convert them and post the correct coordinates for your listings.

[ragbag]

There is a 200 metre difference in the north-south co-ordinates between NAD27 and WGS84.  If you have entered the co-ordinates using NAD27, simply change your GPS to WGS84, and it will do the conversions for you.  Otherwise, you will have to go out to the cache and re-take the numbers.