This is both commentary on the scanning ability of the Epson 4990 flatbed scanner as well as the resolving power of Kodak PanatomicX 35mm B&W film.

On the left side is VERY small cropped selection of a 28mm f2.8 Canon FD lens test image from March of 1980. I was using 35mm PanatomicX and scanned using my Epson 4990 flatbed at 4800 dpi. The realities are that the scanner can not accurately resolve anywhere near 4800 dpi however. On the actual negative in the area marked with the red outline the line triplets can be readily resolved when viewed with a microscope. Because of this, I was left with the issue of representing what the original negative actually looked like as a 'positive image'. I downloaded a vector graphic of the 1951 air force resolution chart and rasterized it at a fairly high resolution and then down sampled it to approximate the line resolving power that can be seen in negative. Not only was there higher resolving ability than the Epson 4990 scanner afforded but slightly higher than the 4800 ppi I was attempting. Trial and error led to an approximation of around a 7400 pixel wide image which ball park is more like a PERFECT 5200 dpi scan. Coincidentally, this is in turn is very close to a theoretical 36MP digital sensor with a near perfect lens. This approximation of the actual test negative print can be seen on the right hand half of the image above.

My old inexpensive 28mm lens was VERY sharp, especially in the center when stopped down to f8.0.
The 4990 scanner can generally depict garden variety 100 and 200 ISO color negatives of that era very well but the resolving power of this long discontinued B&W film is leagues beyond those color films.

Edit 2014: It is likely that the Sony a7R with the superb Zeiss 55 f1.8 could match or exceed this Panatomic X res shot.