Sharing GeoTIFFs Between ArcGIS and GeoMedia

There’s been a very interesting discussion on the GeoMedia email list hosted by Directions Media that has since moved offline. The basic discussion has been about sharing GeoTIFFs between the ArcGIS and GeoMedia platforms.

The initial question is as follows:

"What is the best way to preparing GeoTIFF in INGR environment (GM, I/RAS
C, ISRU…) for using it in ESRI’s ArcGIS?
How to transmit a georeference?

Can I have a SINGLE (!) GeoTIFF file which can be correctly opened in
both lines – INGR and ESRI? "

This made me think some because I’ve been sharing GeoTIFFs (in the State Plane Coordinate System) between ArcGIS and GeoMedia for a few years now. When I posed that comment (I believe offline) to another member on the list (Steve Frost), here was the reply (privately):

"From our experience the problem arises when you have a non-standard projection. If you have a standard projection such as UTM then I believe there is no problem (or presumably a State Plan Projection – though we have no need of those on this side of the pond!). However, if for example you define your own instantiation of a projection – such as a local Transverse Mercator – then the fun starts!…

We have worked round the problem with an in-house application that bulk updates the GeoTIFF tags…."

I did do some additional research with Intergraph and did get a reply on how GeoMedia deals with GeoTIFFs:

"The GeoTIFF spec uses standard coordinate systems defined by EPSG. If the user’s coordinate system isn’t defined by EPSG, then we [Intergraph] write a ‘custom’ tag, containing all the particulars of the projection. The way this is done is well defined in the GeoTIFF spec, and Intergraph follows it pretty religiously (since we helped write it)."

It’s also interesting to note that apparently the issue has been fixed with ArcGIS 9.2.