A single lens profile has segments that match different combinations of focal-length, aperture size and focus-distance in it, already, so it does decide which of those to use, but that would be all in the SP 90mm profile.
If you’re getting another lens profile and you cannot see your normal lens profile list, then I suspect you’re viewing a non-raw file: jpg, tif, psd, etc.
Lens profiles are specific to raw and non-raw formats because cameras and software can already correct for lens issues. My 7D2 can be configured to correct for geometric distortion, chromatic aberration and vignetting or not for the JPGs it produces and obviously LR (and PS) can save JPGs from raw files that already have lens corrections applied.
If you were adjusting a camera-produced or LR/PS-produced JPG, there is no way Adobe software can tell if you’ve applied those corrections to that non-raw file so it doesn't automatically apply a raw-only profile to a non-raw image.
A very few non-raw formats have lens profiles from Adobe, although you can sometimes find third-party sources for them.
If all the files you’re dealing with are raw format, then can you upload one that detects the lens properly and one that doesn’t, to dropbox.com and post a public share link, here in a message, so others can analyze?
Thanks for the response. I am looking at two .dng files, both taken with the same Tamron Macro SP 90 lens. For one of the photos, Lr lists the correct lens, for the other it assumes that it is Tamron Di 28-75 - no other choices are given. I am confused and I realize that this issue exceeds my technical capabilities!
One of the DNGs could be created from a JPG or other non-raw format. When you are looking at the DNG with the wrong lens in Develop, check the WB (White Balance) adjustments up top, are they relative adjustments like -150 to +150 or are they absolute from 2000 to 50000?
Relative adjustments indicate a non-raw format.
Can you upload the DNGs to http://www.dropbox.com/ and post a share link, here?
I need to do a little more homework to determine if the wrong lens detection by Lr is because the files are in JPEG format. Thanks again for your help
Checking the WB Color slider to see if it has a range of -150 to +150 is any easy way to figure this out.
So far your theory is holding! Thanks!!