I agree very hard to see the difference. There is no reason to be nervous buying a lens, buy it second hand and when you want something different sell it and buy something else. Every lens and in many cases an individual lens has some pros and cons, but don't worry about the color nobody will be bothered by the very small differences. Don't worry about sharpness for video because it is in most cases not a issue.
the old tamron sucked at focussing....i never liked it but the image quality was great. Canon f4 is much smaller and that makes a real difference ( i even dropped my 2.8 because it becomes heave after logging it the whole day lol )
Maybe you also wanna condider sigma os version which is good and focuses good....just find one with a good price on the secondhand market ...not happy play with it ..sell it and buy another
the old tamron sucked at focussing....i never liked it but the image quality was great. Canon f4 is much smaller and that makes a real difference ( i even dropped my 2.8 because it becomes heave after logging it the whole day lol )
Maybe you also wanna condider sigma os version which is good and focuses good....just find one with a good price on the secondhand market ...not happy play with it ..sell it and buy another