If your tamron 28-75 lens is 67mm, the two filters both work for your lens. Please verify your camera's lens thread size before purchase (usually marked somewhere on the lens barrel or printed underneath the lens cap).The number is always preceded by a "ø" (diameter) symbol the two lens difference is the stops. 

For this series, front thread diameter is bigger than the back thread diameter. for example: Back thread diameter (attach to lens): 40.5mm Front thread diameter (attach additional filter/other accessories): 43mm ND FILTER size front thread 37mm 40.5mm 40.5mm 43mm 43mm 46mm 46mm 49mm 49mm 52mm 52mm 55mm 55mm 58mm 58mm 62mm 62mm 67mm 67mm 72mm 72mm 77mm 77mm 82mm 82mm 86mm 

Hi, this variable nd filter supports no vignetting range is 24mm. If the lens out of this range (such as 14）,there would be a little vignetting on images. 

Yes, the nd filter could stop at the end of the ranges. 

Female threads 

The side is labeled with the first and last stop... the others in between are just markings. Each stop does not click into place, but the movement of the ring is fluid and firm. Very easy to adjust.