FoV difference between Tamron 70-300VC and Canon 70-300L

[dilbert]

I was wondering if there is anyone else out there that has shot with both of these lenses and noticed the rather substantial field of view (FoV) difference between the two lenses.

If the Tamron is 300mm at 300mm then it feels like the Canon is maybe 290 or 280. A brick wall or newspaper test makes this very readily apparent.

Has anyone else noticed this?

[neuroanatomist]

Remember that focal length is specified when the lens is focused at infinity...so your newspaper or brick wall had better be rather far away!

[dilbert]

Remember that focal length is specified when the lens is focused at infinity...so your newspaper or brick wall had better be rather far away!

So what you're saying is that the FoV difference is simply a result of "focus breathing" which is something that I did consider as being a possible cause.

[neuroanatomist]

I suspect that's the case.  There is something a little odd about the design about the Canon 70-300L, though.  For example, if you compare it to the Canon 70-200/2.8L IS II, both have the same specified MFD and maximum magnification (47.2" and 0.21x), but obviously the 70-300mm has a 50% longer focal length at the long end.  Canon mentioned a  The Tamron 70-300 VC, despite not being able to focus as close (55.1" MFD) achieves a higher 0.25x maximum magnification.

The 70-300 L has a 'floating' optical system (the 85L II has this, too).  Canon stated, "As mentioned above, the use of a “floating” optical system means that as the lens is progressively focused closer, other lens elements continually change position to preserve image quality throughout the focus range. (Many lenses are optimized for best quality at or near infinity, and as focused closer, there’s a drop-off in contrast and sharpness… that’s not the case with this new lens)."  It seems something had to be traded for that sharpness when focusing close, and that something translates to maximum magnification, apparent focal length, or FoV at the long end (three ways of saying the same thing, sort of).

[AprilForever]

I was wondering if there is anyone else out there that has shot with both of these lenses and noticed the rather substantial field of view (FoV) difference between the two lenses.

If the Tamron is 300mm at 300mm then it feels like the Canon is maybe 290 or 280. A brick wall or newspaper test makes this very readily apparent.

Has anyone else noticed this?

How do you like the lens otherwise? I loved my 70-300 IS non-l, but the IQ was just too bad...

[pj1974]

I suspect that's the case.  There is something a little odd about the design about the Canon 70-300L, though.  For example, if you compare it to the Canon 70-200/2.8L IS II, both have the same specified MFD and maximum magnification (47.2" and 0.21x), but obviously the 70-300mm has a 50% longer focal length at the long end.  Canon mentioned a  The Tamron 70-300 VC, despite not being able to focus as close (55.1" MFD) achieves a higher 0.25x maximum magnification.

The 70-300 L has a 'floating' optical system (the 85L II has this, too).  Canon stated, "As mentioned above, the use of a “floating” optical system means that as the lens is progressively focused closer, other lens elements continually change position to preserve image quality throughout the focus range. (Many lenses are optimized for best quality at or near infinity, and as focused closer, there’s a drop-off in contrast and sharpness… that’s not the case with this new lens)."  It seems something had to be traded for that sharpness when focusing close, and that something translates to maximum magnification, apparent focal length, or FoV at the long end (three ways of saying the same thing, sort of).

That's right!

Though I have not used the Tamron 70-300mm VC, but I've had a few other Canon lenses - and noted that at the same marked mm (eg even lower settings 100mm and 135mm on other lenses - and I think also the 300mm setting on my old Canon 100-300mm USM) - that the 70-300mm L doesn't seem as magnified.

It probably does seem like the 300mm of my 70-300mm at minimal focal distance is around 200 - 240mm-ish (depending on what other lenses it is compared with).

And yet - the good news is compared to several other tele lenses at around 300mm, the Canon 70-300mm L appears very sharp at minimum focus distance. I love it for eg dragonflies, some flowers and other details up close, / even 'tame' birds that allow me to get very near to them.

I was going to get the Tamron 70-300mm after looking at some reviews - even bought a filter to it (to replace my Canon 100-300mm USM) - but then the Canon 70-300mm L came out. I used the Canon 70-300mm L from a camera store (who allowed me to stand outside and try it) - and I was SO impressed... and I was hooked and bought one - got it for a reduced price, already just a few weeks after it was available.  I haven't looked back.

The Tamron 70-300mm  VC looks like a decent more budget oriented option, I was going to get this over the Canon 70-300mm nonL - as that Canon's micro USM AF isn't what I like, plus the lens build was not quite up to scratch - though they are fairly close in image quality at the tele-end....  All the best with your photography, dilbert.

Regards

Paul

[LetTheRightLensIn]

I was wondering if there is anyone else out there that has shot with both of these lenses and noticed the rather substantial field of view (FoV) difference between the two lenses.

If the Tamron is 300mm at 300mm then it feels like the Canon is maybe 290 or 280. A brick wall or newspaper test makes this very readily apparent.

Has anyone else noticed this?

Yes, the tamron barely bleeds any focal length while the 70-300L focus breathes heavily. Even at 50' it still breathes compared to the Tamron.

I still like the 70-300L better for sure though.

[TWI by Dustin Abbott]

I currently own both lenses and intend to write a head to head review when I get back from my current business trip.  I definitely noticed this phenomena, tested it, and discovered the 70-300L does heavily focus breathe but is basically identical to the Tamron out past about fifty feet.  It is definitely nicely sharp up close, but then so is the Tamron.

One thing I will say (and probably the primary reason that I will keep the Canon over the Tamron other than weathersealing) is that Canon has MUCH smoother transition to ooF area (bokeh).  That was the big weakness of the Tamron.  It has that "nervous" bokeh that I have often dealt with in post (I have owned the Tamron since it came out but just recently got the Canon).  The 70-300L is shockingly good for a small aperture lens - even at distance when there isn't much separation between the subject and the background.  I took this picture of an owl last week and was really shocked at the difference.  I was shooting from about 40 feet away, and so there was lot of distance between me and the owl and very little between the owl and the trees behind, but the oof focus area is still very smooth.


The Grey Owl by Thousand Word Images by Dustin Abbott, on Flickr

[dilbert]

I was wondering if there is anyone else out there that has shot with both of these lenses and noticed the rather substantial field of view (FoV) difference between the two lenses.

If the Tamron is 300mm at 300mm then it feels like the Canon is maybe 290 or 280. A brick wall or newspaper test makes this very readily apparent.

Has anyone else noticed this?

How do you like the lens otherwise? I loved my 70-300 IS non-l, but the IQ was just too bad...

The Tamron 70-300VC is much better than the 70-300 IS USM (non-L). Much better than the reviews suggest (I have two copies of the non-L) because I found that at 300mm, the non-L Canon was delivering results that were just way softer than what I wanted (said lens had been to Canon for "calibration").

[GMCPhotographics]

I was wondering if there is anyone else out there that has shot with both of these lenses and noticed the rather substantial field of view (FoV) difference between the two lenses.

If the Tamron is 300mm at 300mm then it feels like the Canon is maybe 290 or 280. A brick wall or newspaper test makes this very readily apparent.

Has anyone else noticed this?

There's a few lenses which focus breathing is really apparent and the Canon 70-300L is one of them. At MFD, the 300mm rating is slightly less than 200mm. Which is quite extream. Most macro lenses do the same due to their interal focussing design. The Canon 70-200 lenses (IS / f2.8 /f4 ect) hardly breath at all, where as the Nikon's do. The VRII is well known to be nearly 135mm at MFD. Each lens has to be evaluated for it's strengths and weaknesses. Most review web sites are such a poor level of testing, they rarely spot this vice consistently.
Another observation is that none of the Canon 70-200 mm lenses are particularly sharp at their Min Focus distances. They are usable but even racked out to a few feet more and they really sharpen up. The 70-300L is sharp all though it's focus and zoom range. While it looses focal length at close focus distances, it's more usable and sharp. Again...I've not seen a reliable test site which even begins to unpack this.
All lens formulas are a set of compromises. The flare and star bursts from the Canon 70-200 f2.8 L IS II is really ugly, the Nikon version fares better and the 70-300L is really nice in this regard. They are all sharp lenses, the 70-300L is particularly sharp. On paper one wonders how useful it would be. In real world use, it's probably more useful to many more photo genres than the sports / press orientated 70-200 lenses. Landscapes, travel, documentary, details, a bit of wildlife...etc

[neuroanatomist]

In real world use, it's probably more useful to many more photo genres than the sports / press orientated 70-200 lenses. Landscapes, travel, documentary, details, a bit of wildlife...etc

Well, they'll get my 70-200 II when they pry it from my cold, dead hands (or Canon releases a MkIII), but I might pick up a 70-300L as a travel zoom...

[AprilForever]

In real world use, it's probably more useful to many more photo genres than the sports / press orientated 70-200 lenses. Landscapes, travel, documentary, details, a bit of wildlife...etc

Well, they'll get my 70-200 II when they pry it from my cold, dead hands (or Canon releases a MkIII), but I might pick up a 70-300L as a travel zoom...

That's about how I feel about it...