It’s Here!
Hi! Welcome to the first LIO Blog. As the coordinator of Land Information Ontario I work directly with hundreds of private and public sector organizations that create, manage and use digital geographic information. The intention of this Blog is to discuss the underlying, often universal, issues encountered by those organizations as they implement their various initiatives. I expect these stories to strike a chord with many of you, and I look forward to your comments, especially your suggestions, on ways to respond to these challenges.
I intend to talk about the perils of crowdsourcing, the future of data warehousing, the seduction of Web services, and the unfettered joy of Metadata (honest!). Upcoming pieces will deal with the sometimes dangerous ways in which data intended for one purpose is used for a different purpose, or combined with data from multiple sources. I hope to cover issues around the collection and management of imagery; the role of mass market Geomatics like Google Maps and Microsoft Bing in internal GIS shops; and the use of geospatial data and functionality by mainstream developers and non-GIS users.
Over the coming months we may deconstruct technical jargon and peel back the hype on new products or new approaches. We will definitely cross the floor to see that there are strong similarities between aboriginal, transportation, health, education, resource management, economic development, land use planning, and environmental protection issues when it comes to geographic analysis.
I look forward to this conversation and hope to provide food for thought. Frankly, it really won’t work without you. So, respond early and write often. I do not have a monopoly on experiences, and all of you have something to share that the rest of the readers will find interesting. Take care, and stay well…
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Good luck with your blog, Raphael, and well done for starting it.
One topic that I’d be interested in you “hosting” relates to why geospatial data is still so little used in strategic level decision making (yes I know it’s used more than previously, but most of its use is still at the tactical level).
Bob
I look forward to postings of “unfettered joy,” as you have promised!
Raphael,
Good luck with this!
George
Excellent idea to host this blog. Particularly interested in the notion of crowdsourcing, data integration and respective roles of government and private sector for topographic mapping.
Excellent idea!! I’m looking forward to seeing some of the discussion topics. While I’m here, does anyone know how to fix NAD shift issues? I sometimes experience a data inaccuracy issue of around 200 metres with field data. I was told that this related to an issue between the NAD27 and NAD83 datums. I find this problem particularly apparent when I try to add field data to the OBM_FULL_I data server hosted by ESRI via ArcIMS.
For the most part, PMs want their maps quick-and-dirty. Using the ArcIMS server allows no flexibility from the standpoint of asthetics, but it is much quicker than ordering the data and changing all the proprties, etc. I often try to drape LIDS data on top of IMS server data and experience the same problems. If anyone knows a patch for this, your suggestions would be greatly appreciated.
Cheers everyone, and I hope this blog is successful Raphael!!
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Dan, In response to your question, I understand that you are using OBM_FULL_I from ESRI and then, while in ArcIMS, you add new data downloaded from the LIO Warehouse. You find that data from the two sources do not align and are out by approximately 200 m. You suspect that the issue is that data from the two sources are made available in two different datums, NAD27 and NAD83. This is possible, and the 200 m would be about right, depending on what part of Ontario you are mapping.
The way that we recommend avoiding the datum shift issue is to use Web Services, such as OGC-compliant Web Map Services whenever possible, rather than downloading data. If you are using ArcGIS desktop you only need your own data, or the data upon which you wish to do the query/analysis, locally. The Service should supply the background data in the same data and projection as the data already on your system.
Since your question specifically addresses data provided from LIO, I will send your note to LIO Support Services (lio@ontario.ca) for further investigation. Should you wish to send your question to a Forum, I recommend joining any one of dozens of GIS forums around, such as geonet_list-bounces@lists.ec.gc.ca.
Thank you very much for the idea. I will raise the subject of datum incompatibility as an obstacle to easy data sharing in a larger context, and it is definitely an issue of concern to many GIS practitioners.