How can you tell which band is the infrared on a .sid aerial

[JenniferRoath]

I have a .sid raster that apparently has infrared. But it only has 3 bands, making it most likely RGI or something similar. My metadata does not specifically tell me which band corresponds to which wavelengths. When I load it into GIS it defaults to R=band1, G=band2, and B=band3. Is it safe to assume band 3 is infrared? Is there a way to know for sure? I have no other supporting documentation to help me, just the raster. -- Thanks

Note: there is a slight possibility that the image does not actually have infrared. When I look at the lake, it is almost black like other false color images suggesting it probably does have infrared. I just need be able to know without a doubt if I have infrared or not.

[DanPatterson_Retired · Accepted solution]

metadata is the only way you can tell for sure.  Any band can be applied to R,G,B including 3 bands not visible to the eye. Your image is no more than a picture until you can track down what bands were used to construct it.

[JenniferRoath]

Thanks! I'm fairly certain now that they sent us the wrong aerials. I just needed to be sure before going back to them.