BobT wrote:
I'm mainly interested in which lens is more capable of delivering the better sharpness at/near 300mm. I've read the specs for the Nano version, and once had the original 70-300 IS USM non-L version. But the IQ (especially the sharpness) has not been discussed very much, especially with the newer Nano version.
I'm considering one of these lenses to replace my Canon 100-400 "L" Mark 1 lens due to it's heftiness, but it does deliver great results. I really need to get useable results close to 300mm wildlife. I know longer would be better, but have found 300mm doable for my purposes. I have the Canon 55-250mm STM lens and find it to be excellent at 250mm, even when cropping. Just need longer. I also have tried the newest Tamron 70-300mm lens, but was disappointed in it's results. However, I may have had one of the bad samples (rather common) with that lens; as many do rave about it.
I'd really appreciate hearing from actual users about this; as I know the written specs pretty well.
I'm mainly interested in which lens is more capabl... (
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I agree with an earlier response that the Canon EF 100-400mm IS USM "II" is your best bet, though it's a lot more money. Partly that's because it uses a fluorite element, which all the 70-300s lack. Fluorite really helps with chromatic aberration in powerful telephotos.
300mm really isn't much more "reach" than 250mm you've already got. 400mm... well that's a noticeably longer lens! If the current 100-400L "II" is too costly, you might consider the first, push/pull zoom version... It's also quite good and can still be found new at some hefty discounts, or even cheaper refurbished (at Canon USA website) or used.
The exception would be if you plan to shoot video with the lens. If so, then the Nano USM lens would be a better choice. It's quieter/smoother focusing, so more ideal for video work.
See the detailed review of the 70-300s at
https://www.the-digital-picture.com/Reviews/Canon-EF-70-300mm-f-4-5.6-IS-II-USM-Lens.aspxYou also can use the comparison tool at that website to see for yourself image quality from the two lenses (as well as the 100-400mm II, if you wish). Spoiler alert! Bryan Carnathan didn't find the image quality all that different, between the original 70-300mm IS USM and the "II" with Nano-USM. He felt the focus performance, improved IS and stylish new design were more significant differences.
There is a new Tamron 100-400mm VC USD lens coming soon.... don't know the details yet, but I expect it will be priced a lot lower than the Canon 100-400mm. It doesn't include, but is designed to be able to optionally fit a separately sold tripod mounting ring. Sigma already has a new 100-400mm OS HSM "C" lens available that looks to be competitive at about half the price of the Canon 100-400L II. The only thing I don't like about it is that there's no means or option to attach a tripod mounting ring. When a lens can reach 400mm, IMO it absolutely needs a tripod mounting ring! (Especially if it will be used on a crop sensor camera.)
Regarding possible camera upgrade....
T2i isn't all that bad. It's sensor is two-generation old 18MP, same as a pair of 7D I used for five years before updating to a pair of 20MP 7D Mark II. 80D is newer... it and T7i, 77D, T6i all use the latest generation 24MP APS-C size sensor. But you won't see a huge difference in IQ. Used right, the 18MP cameras are quite capable.
The biggest difference with a newer camera would be autofocus performance.... both the viewfinder based system and Live View on the latest models.... and possibly some other things such as reduced shutter lag, higher frame rate continuous shooting, larger buffer, maybe a bit higher usable ISO.... plus the rather silly stuff like WiFi, GPS, a direct line to Starbucks to pre-order your preferred coffee drink, etc.