A long time ago when there was still printed documentation, the Understanding Map Projections book had a foldout table in the back. The table listed all the map projections and had information about various properties and characteristics.  Bojan Šavrič Bojan Savric undertook to update and modernize the table including changing the categories and adding new projections. We hope you like the new style! It will easily fit on a 8.5"x14" or 11"x17" page if you want to print it out. Here's the 11x17 version on my office door: It's complete through ArcGIS Pro 2.5 and ArcGIS 10.8. We're adding 3 new projections to those releases: Adams square II, Tobler cylindrical I, and Tobler cylindrical II. Melita   ... View more

Hi everyone Can anyone make heads or tails with these coordinates? It is from a survey of a lot that I need to map into a BIM program as a site plan and I am deeply confused! The distance between points is clear but the remainer (mainly how the coordinates are written) is quite unclear to me.  Thank you in advance !! ... View more

I am working to resolve a transformation issue from KY Single Zone, US Survey Feet, NAD83(2011) to NAD83(86). Unknowingly, I have used NAD83(86) for several datasets where I should have used NAD83(2011). Using the transform features tool in ArcGIS Pro 2.9.2, I have transformed the data in a series of steps from EPSG 6473 to EPSG 3547 to EPSG 3091 to EPSG 3089. The largest shift occurs from 3091 to 3089, as expected- this is the shift from the HARN reference frame to the NAD83(86). The transformation for my coordinate results in a shift of 0.94 US Survey Feet to the northwest, as shown in the attached "Image with Labeled Points" as the blue balloon to the red circle. This is consistent with what the expected shift would be- so far so good. For extra confirmation that I am observing the correct shift, and before I begin updating any of the affected data, I used the NGS NCAT tool (https://www.ngs.noaa.gov/NCAT/index.xhtml) to convert the state plane coordinates at the location shown in the "Image with Labeled Points". I used the settings shown in "NGS NCAT Conversion" image. The SPC Zone is KY Single Zone, US Survey Feet and the reference frames are NAD83(2011) to NAD83(1986). The NGS NCAT provides output geographic coordinates with and without transformation. I can import these into ArcGIS Pro using the Add XY tool with GCS_WGS_1984 coordinate system. These imported points are shown in the "Image with Labeled Points" as the NGS NCAT Input and Output. The shift between NGS NCAT input and output has a similar magnitude (1.06') but is not the same as the result obtained using transformation in ArcGIS Pro. The shift direction (northwest) is the same to close approximation. The points are not located over the state plane coordinates shown as blue balloon and red circle, however, and are offset by 2.98' feet. Is there an explanation for why I would obtain different results using transformation in ArcGIS Pro versus the NGS NCAT tool, and why I am seeing an offset in my NGS NCAT geographic coordinates? I would appreciate any advice from this community. ... View more

Hello my fellow Canadians! Lately I have been researching more and more about transformations from NAD 1983 GCS to NAD 1983 CSRS GCS, and then NAD 1983 CSRS into WGS 1984 Web Mercator (auxiliary sphere), and the more I read, the more confusing it gets. There are a few articles I have found, but they seem to be dated.   This article   is absolutely fantastic (shoutout to all of the ESRI Blog Creators, your information is invaluable, and has helped me immensely), but I don't think it has been updated to fit 2021 and all the changes that has happened to NAD 1983 CSRS.   This article   states: Please note that different Geographic systems need specific transformations. As of 2018, CSRS v6 and v7 are becoming very popular - however there is no specific transformations available at this time. If using ArcGIS 10.6x, the newer v6 and v7 Geographic systems are available With that being said I am using both ArcGIS Desktop 10.8.1 and ArcGIS Pro 2.8. From the first article I linked, I downloaded the ON83CSv1.gsb from LIO / Geohub and created a custom transformation that transforms data from NAD 1983 ORIGINAL to NAD 1983 CSRS. This works perfectly to align data that has been projected in NAD 1983 to transform on-the-fly into NAD 1983 CSRS: My confusion comes from the latter part of the article where Ms. Sibbet talks about doing a transformation to WGS 1984 Web Mercator (auxiliary sphere) in order to upload to ArcGIS Online (which I do a lot, hence I want to get this right). Generally. she states that if transforming from NAD 1983 CSRS to WGS 1984 Web Mercator (auxiliary sphere), one should use the transformation:  NAD_1983_CSRS_To_WGS_1984_2. In her example, she uses her custom transformation followed by NAD_1983_To_WGS_1984_2: After all this background info, I am finally getting to my question. Currently ArcGIS Pro is defaulting to the following: And it aligns perfectly. For curiosity sake, I tried this: And it resulted in slight misalignment. I am wondering why 'we' are now using WGS 1984 (ITRF00) to NAD 1983. The following transformations in the photo BELOW work perfectly to align everything precisely, but I am confused about the deviation from  NAD_1983_To_WGS_1984_2 and the implementation of WGS 1984 (IRF00) TO NAD 1983 I understand the common practice is to avoid projecting on the fly, but this doesn't just apply to that, it also applies to transformations when reprojecting data, so I'm trying to understand it all! Thanks in advance! I look forward to hearing your thoughts. ... View more