JonathanChemE wrote:
I am mostly into wildlife photography and landscapes but do need to carry around a camera some for my street tourist type stuff, and I do the occasional portrait or group sometimes. My body is a T7i. I have an EFS 10-18 IS STM, a EF 50MM IS F1.8, an EFS 18-135 IS STM, an EF-S 55-250mm F4-5.6 is STM, an EF 70-300 F4-5.6 IS USM and a Kenko TELEPLUS Pro 300 DG 1.4X Teleconverter for Canon EF Mount. What I am thinking is that I could trade everything, except the 10-18 and 50mm in on a used Tamron 18-400 and only be out a couple of hundred dollars and have a much simpler kit. My question is I am giving up some lens performance quality by going to the one lens verses changing out the lenses as needed? I don't need to change lenses often. If I am in a general location I use the 18-135, if I am doing landscapes I switch to the 10-18 sometimes. Usually I a know I am doing wildlife and have one of the long lenses on. Before I make the switch my wife, who is my main critic (in a good sense of the word) wants me to be sure it would be a good move. I have tried to research the lenses but no good side to side comparison between the 70-300 and 18-400. Thanks for your input.
I am mostly into wildlife photography and landscap... (
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You will be giving up a lot of image quality, going to the Tamron all-in-one zoom. For what it is, it's good. But that type of lens always compromises to some extent.
You can compare test shots done with the Tamron lens against shots done with an 18-135mm here:
https://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=1145&Camera=963&Sample=0&FLI=0&API=0&LensComp=809&CameraComp=0&FLIComp=0&APIComp=0And you can compare the Tamron against an EF 70-300mm lens here:
https://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=1145&Camera=963&Sample=0&FLI=2&API=1&LensComp=738&CameraComp=963&SampleComp=0&FLIComp=1&APIComp=0While the Tamron lens is good for a 20X zoom, it still falls well short of what less extreme zoom lenses can do. You also should expect it to focus more slowly. I haven't used any of the Tamron "HLD" lenses, but that sounds like some form of micro motor focus drive to me. I am fairly certain the Canon USM lenses will out perform it for focus speed. Especially if you have the 70-300mm "II", with the new "Nano USM" focus drive. The Tamron might equal the focus drive of your 18-135mm "STM" lens. According to Canon the newer 18-135mm USM, which also has the new Nano USM drive, is 2X to 4X faster focusing than the STM version of that lens. They are optically identical, though, so don't expect any difference in image quality (both are very good).
The EF-S 55-250mm STM also is a very capable lens. I didn't set up a comparison between it and the Tamron, but you can if you wish at the above site.
The Canon EF 100-400mm lenses someone mentioned above are in a whole different league than the 55-250mm, 70-300mm and the Tamron lens. Especially the 100-400mm II is a superb zoom... very well built and offering some of the best image quality of any telephoto zoom. Yes, it's bigger and heftier (3.5 lb.) But I shoot with one for 6 to 8 hour days sometimes, with only brief breaks. It's far more than you'll want to spend, though... if you're balking at the cost of the Tamron zoom.
Your best bet would be to keep what you've got and start saving your pennies to add a Canon 400mm f/5.6L USM to your kit some day. Look for used, since it's been around for quite a while. It's extremely sharp and fast focusing, as well as moderate size and weight for a 400mm lens. One thing it lacks is image stabilization. So plan on using it with a higher shutter speed... or with a tripod or monopod.
The Canon 300mm f/4L IS USM is another lens that's quite good and moderate size and weight. It's been around even longer than the 400mm, so is easy to find used for some discount. Nice thing about it is that it has IS. It also works very well with a quality 1.4X teleconverter (I can't say about the Kenko you mention... I use the Canon 1.4X II and find it very good). The 300mm f/4 is not quite as sharp as the 400mm or Canon's 100-400 II, but it's very good and a stop faster than either or those lenses (it becomes a 420mm f/5.6 combo when a 1.4X is attached).
I don't know what 50mm lens you have.... Canon has never made one with IS. The current version they offer is a capable, affordable and cap[able little "STM" lens. That lens superseded the earlier "II" version that wasn't as well made and has considerably slower, noisier and less reliable micro motor focus drive.