Canon 100-400 FOV vs Tamron 18-400 - questions

I have both the 100-400 L and just picked up a Tamron 18-400 as a walkabout lens. I still have a week in which I could return it with no restocking fees.

I am taking a lot of shot with the 18-400 to see if I should keep it. It seemed to me to be a bit short at the far end, i.e. 400mm so I decided to test the FOV against my 100-400 L IS II. Also compared to my 55-250 STM

the 55-250 and the Tamron seem to be about the same FOV, but the 100-400 is different by quite a bit.

on the test against the 55-250 there is a very slight difference and it could be where I estimated the 250mm spot on the Tamron was.

But with the 100-400 there was no doubt that when I zoomed all the way out on both the Canon was showing the same FOV of the Tamron at 400mm but the Canon was at 300mm and then the 300mm was 250mm on the Canon.

Tamron Canon 100-400

300mm 250mm
400mm 300mm

Tamron Canon 55-250
roughly
250mm 250mm


One thing about the Tamron, and helps as a walkabout is that the close focus distance is about 18 inches. In reviews I have heard that the Tamron 16-300 and the older 18-300 are not quite as sharp as the 18-400.

Sharpness, it is really dependent on holding the lens steady and the subject not moving. I have gotten some good sharpness but also alot of hand held shots seem to be a bit soft.

I had thought about the Canon 28-300 and still agonizing over that one, but it is over a pound heavier and 4 times the price! Also close focus distance is 2 1/2 feet vs 18 inches
AND at 28mm, with my 80D that is 44mm equivalent vs 28mm equivalent.

Still agonizing.

Here is a Cardinal I shot Tamron 18-400 at 400mm ISO 1000 1/250 f/5.6 Cropped and sharpened a bit in Photoshop

Keep in mind that, for most zooms, the advertised long focal length is true with the focus at infinity. For short to medium distances, they are shorter.

^^^ yup.

https://en.m.wikipedia​.org/wiki/Breathing_(l​ens)

I will take the lenses outside tomorrow after work and try them at infinity

I will say that the example you posted there is roughly what I would expect, in general, out of the Tamron. It's also pretty damn good for 1/250 @ 400mm....

It just isn't going to perform a ton better than that, given the massive zoom range and lens elements that they're dealing with to create that lens. Some MFA tweaks and such might make a marginal difference, but minimally.

I own both lenses, too; and the Tamron is a great lens for packing a small travel kit and expecting to capture memories of a trip. If picture quality and printing are desired, though, that just isn't your best tool.

Just an anecdotal comment...

I once owned

• a Canon 15-85mm f/3.5,
  
• a Canon 70-200mm f/4,
  
• a Tamron 28-75mm f/2.8
  

Snydremark wrote in post #18690288
I will say that the example you posted there is roughly what I would expect, in general, out of the Tamron. It's also pretty damn good for 1/250 @ 400mm....

It just isn't going to perform a ton better than that, given the massive zoom range and lens elements that they're dealing with to create that lens. Some MFA tweaks and such might make a marginal difference, but minimally.

I own both lenses, too; and the Tamron is a great lens for packing a small travel kit and expecting to capture memories of a trip. If picture quality and printing are desired, though, that just isn't your best tool.

First, I was sitting outside with a cup of coffee waiting for hummingbirds and took both lenses and focused on a tree about 400 feet away and the FOV on both was very similar, so no issues there.

Snydermark
I got this lens for that exact reason, to have one lens when I am going somewhere with my wife that I don't expect to be taking any pictures but may, and don't want to relegated to just my smartphone camera. I do sometimes carry my Olympus Tough pocket camera so that is also an option but I wanted a step up and the 18-400 is it.

Looking at the processed shots I am happy, yes it is not as tack sharp as the Canon but most of the shots are to share, and it is actually rare that I print anything, mostly they get put on my flickr account ( https://www.flickr.com​/photos/jmpadell/album​s )

My final thoughts are that the lens needs plenty of light, or a very high ISO (and live with the grain) and you have to hold it rock steady, but it does work on handheld. I would love the 28-300 L, but the weight and the price make the 18-400 more attractive.