How to read the info with the image

Some of the images are provided with information about the camera, lens, exposure etc.
Not always is this information correct. It is possible that I've used a teleconverter or that Lightrooms database does not pick the right lens. This shows by a different focal length than the lens info provides. The focal length provided with the text Full Frame Focal Length however is the correct one. Almost all lenses have a real 35mm full frame focal length. The only exceptions to this are some rare photos from smartphones or a Minolta Dimage7 Hi. Where the mentioned lens is the MACRO 100mm F2.8 the real lens used is the Sigma 180/3.5 APO MACRO DG EX. Another form of faulty info occurs with the use of extension tubes.

Also when photos have been processed they sometimes loose info in the conversion from RAW to TIFF. I.e. flash info can be lost hence the info "unknown flash" but also the focal length and exposure info can be lost.