Hi Ronnie, I hope you don't mind... I took 100% crops of 3 images at 1600x533px and put them in a single 1600x1600 PNG with no resizing or sharpening:
Not at all and appreciate that you did it. My only concern was that all photos were from the same distance as well as the same state (wide-open or stopped down) and it seems that is the case.
Comments:
I definitely see a difference in sharpness between each lens now, but this really is pixel-peeping and I'm wondering how much it'd matter with a closer subject or in print.
Also, this is pretty remarkable (to me) that a 10+ year old lens with a teleconverter approaches one of the sharpest telephoto lenses in the world.
The difference in contrast I though I saw earlier on my tablet is less apparent here, although the color difference is now more obvious.
To me the sharpness difference is obvious, but I also have access to the full resolution RAW files (but everyone now has access to the full resolution JPGs).
As for a closer subject...…………………….
First, I would have to argue that 90% of the people on this forum who would use any of these lenses would be shooting from a farther distance. While I have no data to back it up (just years of looking at photos on photography forum sites) I would argue that at least 90% of the people who use a telephoto lens in general (any system) would be shooting from a farther distance.
So, shooting from a closer distance would honestly show the same difference. I have photos with the head of a GBH (as well as smaller Herons/Egrets) filling the frame from the 300/4, 300/4 with MC-14, the 150/2, 150/2 w/ EC-14, and 150/2 w/ EC-20 as well as the 50-200 (in all TC combos) and I can easily tell the difference in the amount of detail captured. I have done a comparison of the bare 150/2 vs the bare 300/4 and those two lenses are almost identical and very hard to tell the which was used (I have to look at the bokeh to figure it out). But once I start adding TC's there is a noticeable difference and I think if I was able to do this test from a closer distance the difference would be similar. Yes the 75-300 would provide a better photograph than it does now, but so would the 300/4 and the SWD.
Shooting from a farther distance (which most are going to do) will only widen this difference in sharpness because the other lenses don't have nearly the resolution of the 300/4. I had briefly considered shooting from a farther distance but I always test/compare lenses how I shoot them and not how others shoot them, so I stayed true to my testing.
As for printing? Really depends on how big you are going to print. Based on my printing of images over the last 5 years while using m4/3 I would say if printing small to medium sized there wouldn't be much difference (especially if printing on a textured paper like canvas). I honestly don't think I would find the image of a Tri-Colored Heron I printed 40x30 to meet my requirements if I had taken it with the 75-300. The lens just doesn't have the resolution to capture enough detail when printing that large and wanting to really see the feather detail in a bird. Honestly I am not sure I would have been satisfied if it was taken with the SWD either. The 300/4 is really that amazing of a lens.
As for how a 10 year old lens compared to a new one I am really not that surprised. When Olympus was making the 4/3 lenses they sacrificed nothing for IQ with the SHG lenses, it's why I am so in love with the 150/2. For the HG lenses (which the SWD is) they made them as good as the current Pro lenses in my opinion. To keep size down they have started to use more software correction than they did with the SHG lenses (except maybe the new 1.2 primes, which are stellar in my opinion). I have said for a number of years now that the new Pro lenses are about the same as the old HG lenses and I still believe that. I may just have to shoot the bare SWD against the 300/4 by matching framing and see how it compares, just like I did with the 150/2.