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Near-real time satellite imagery?

Posted: Tue Jun 06, 2006 1:22 pm
by SteveB
Anyone know of any place to view near-real time satellite imagery? Sort of an updated Google Earth (theirs can be years old)? I'm mainly interested in peaks and passes in the Sierra... :)

Thanks!

Posted: Tue Jun 06, 2006 6:24 pm
by ERIC
Well, unfortunately there isn't much out there for free... However, if you know a little about GIS and have some software, this is the best that's out there:

http://new.casil.ucdavis.edu/casil/remo ... naip_2005/

It's the National Agriculture Imagery Program (NAIP) and it's high resolution (1M) aerial imagery. They acquire the entire state once a year. The latest is 2005 data. The files are VERY LARGE in size (you'll need a broadband connection), but worth it once you see the quality. At 1M, you can pretty much make out hikers on the ground!

There's a free trial version for a viewer that will allow you to open and view this imagery. It's called GeoExpress and you can download it here: http://www.lizardtech.com/products/geo/

The better option (but a lot of money) would be ESRI software (ArcGIS), or any other GIS software that supports MrSID (.sid) files.

Another source for imagery you might check is http://www.airphotousa.com/ Some of the imagery might be more current than Google Earth, but the images are also watermarked unless you purchase them. And one more that's similar to Google Earth is TerraServer-USA: http://terraserver.homeadvisor.msn.com/

Hope this helps, and good luck!

Posted: Tue Jun 06, 2006 9:49 pm
by ironmike
I'm sure the NSA could help you out.

Of course, they'd have to kill you.

MappingTheOutdoors.com

Posted: Sat Jun 24, 2006 9:05 am
by ERIC
I found another resource that some of you might be interested in. The imagery isn't the best, but it's pretty cool how they overlay topo lines on the imagery. Take a look:

http://www.mappingtheoutdoors.com

mappingtheoutdoors.com

Posted: Tue Jul 18, 2006 6:19 am
by shane4169
We use higher resolution color aerial photography when we print our maps as well. Do to the file size of the color aerial photography, we dont display them over the internet. However, in locations where up-to-date photography is available, we use it on the printed map. We have up-to-date color photography for most of the US. If you have any questions, visit our FAQ page, or email me and I will personally respond to your inquiry.

Posted: Tue Jul 18, 2006 8:35 am
by ERIC
So, the preview on your website shows a low resolution satellite image (at least for every Sierra Nevada location I looked up) but you're saying that mappingtheoutdoors.com prints off current high resolution maps "most of the time"? I looked at your FAQ section, and didn't see any mention of resolution or current data. I did see some good examples in the examples section, though. But I have not found anywhere on your site where it clearly says you use higher quality data for the print even if the preview is low res. How am I supposed to know if the map I order is going to be high res without an accurate preview? Personally speaking, I like to see what I'm purchasing. And there are other sites out there that do not have a problem displaying previews of higher resolution imagery. :-k

Mapping The Outdoors

Posted: Tue Jul 18, 2006 9:25 am
by shane4169
I just posted two maps that show the areas that we have the new 2004 and 2005 Color Aerial Photography. Thanks for pointing that out. We always appreciate input to help better serve our customers.

Just a note, we do not use satellite imagery, it is aerial photography taken by plane. And the file size for 1 single county can often exceed 3 Gb in size. So it is virtually impossible to display this type of data over the internet.

The imagery you see on the sample maps page is a sample of the color aerial photography that we use.

Any questions or comments? Feel free to email me.

Posted: Tue Jul 18, 2006 10:09 am
by ERIC
Thank you for clarifying. So the b&w previews displayed on your site are old USGS DOQQ's? If not, what's your source? Just curious is all...

I'm aware of the imagery you are probably using. I work for an international aerial imaging company, and have worked closely with a few of the companies who acquire the imagery for NAIP (IK Curtis in Burbank, CA for one). The files are indeed very large, as MrSID files tend to be. A good chunk of the 2004 project was acquired at 2M resolution and very few counties exceed 2GB in size (most are less than half that). The 2005 1M data is a different story... However, there are ways in which those files can be incorporated into a website; i.e. automated data query conversion. In a nutshell, this process takes a "snapshot" of the user-defined target area on a MrSID file running behind the scenes and generates a compact jpeg file for display on a website. More than likely hundreds of terabytes of storage space would be required to house the original MrSID data spanning the entire USA, but that's par for the course in the world of remote sensing these days. ;)