IBE

Hello everyone. I shoot with a Canon 5D M III. I have a great 35-70 L . I sometimes do some wildlife with a prime 300L. Not quite the reach I would like. I have a doubler which gives me a much better reach but the loss of quality and useful auto focus is unacceptable. Thinking about selling the 300 and purchasing a Tameron 200-600G2. Any thoughts appreciated
IB

maggiemae Loc: North Carolina

I know nothing about thkse lenses but if you want more reach and can afford Id say go for it.

CHG_CANON Loc: the Windy City

Doubling a 300 f/4L still gives you the center AF cluster on the EOS 5DIII at f/8. Are you using AI Servo that causes the camera to continuously focus, where single-shot at f/8 really is sluggish? In AI Servo, what case mode are you using?

The center-point AF on the EOS 5DIII makes a number of extended options problematic. The EF 100-400L II is an excellent lens with the 1.4x extension to an effective 560mm, but again with the center point limitation. For sluggish AF, there's also the question about whether you're using series III extenders?

You might want to rent a Tamron rather than buying without ever handling. The lens is much larger than your current configuration. Given your experience with a fixed focal length prime, you might also consider the EF 400mm f/5.6L and the option to extend to 560mm f/8. I'd start with a series III 2x and AI Servo before moving onto any new lenses.

You might look at some used / discontinued models like:

Canon EF 300mm f/2.8L IS USM (original 'v I' IS version - doubles to 600mm f/5.6)
Canon EF 300mm f/2.8L USM (even older non IS version - doubles to 600mm f/5.6)
Canon EF 400mm f/2.8L IS USM (original 'v I' IS version - doubles to 800mm f/5.6)
Canon EF 400mm f/4 DO IS USM (original 'v I' version)
Canon EF 500mm f/4L IS USM (original 'v I' version)

imagemeister Loc: mid east Florida

You really have to tell us WHICH version of the 300L you are using - also, which version of the 2X you are using ?? ...... The series III extenders are only an advantage for series II lenses.

You might also look at the 400 5.6 L and a 1.4X II.

I am not a big fan of f6.3 lenses. If AF speed and accuracy matters, you will want a Canon lens.
.

amfoto1 Loc: San Jose, Calif. USA

If yours is the EF 300mm f/4L "IS" USM, it works very well with the Canon 1.4X "II" teleconverter, which can be picked up used for relatively little money. I see them sell used for $250 or less. Often $200 or less. (And I have little concern about buying a used teleconverter, since there are very few moving parts in them to wear out.

EF 300mm f/4L IS USM with EF 1.4X II teleconverter, on full frame 5D Mark II:



Enlarged detail from above:



If yours is the older, non-IS version of that lens, I don't know how well it works with teleconverters. But it's probably worth a try. I've often heard that the non-IS 300mm f/4L is even sharper than the IS version, so it would likely give good results. A "weaker" 1.4X teleconverter will usually give better image quality than a 2X (but you also don't mention which 2X... and that might make a big difference... there are good ones.... and there are bad ones).

If yours is any of the EF 300mm f/2.8L lenses, well that's a whole different thing. Mine works extremely well with either Canon 1.4X II or 2X II. The Canon 300mm f/2.8L lenses are some ot the sharpest lenses anyone has ever made and they "tolerate" a lot of teleconverter. Somethings wrong, if that's the lens you are using and you don't like the IQ from your combo (maybe a third party teleconverter?).

Another thing you can do for "more reach" is pick up a Canon APS-C camera to use with the telephoto lens (and teleconverter). That's like putting a "free" 1.6X teleconverter on the lens. What I mean by "free" is that there is no loss of light, the way there is with an actual teleconverter. A 300mm f/4 lens with a 2X "becomes" a 600mm f/8 combo... Or with a 1.4X it "becomes" a 420mm f/5.6 combo. In contrast, using that 300mm f/4 directly on a 90D, 80D, 70D, 7D Mark II, 7D, 77D, T8i, T7i, etc. it will "act like" a 480mm f/4 would, on your 5DIII full frame camera. Of course, you also add a 1.4X and end up with a combo that "acts like" 672mm f/5.6 would on full frame.

EF 300mm f/4 lens with EF 1.4X II on APS-C camera (7D):



Some of those recent APS-C models even have similar or higher resolution than your 5DIII (22MP).... The 70D and 7DII are 20MP... the T8i, T7i, 77D and 80D are 24MP.... the 90D is 32.5MP (higher resolution sensor even than full frame 6DII, 5DIV, EOS RP or EOS R... only the 5DS/5DS-R have more with 50MP).

Of course, it's not quite the same quality with APS-C... there are still some benefits to using full frame! But it can come surprisingly close these days. And one place that APS-C cameras really shine is when they're used with telephotos for sports and wildlife photography.

Not that the Tamron 150-600mm "G2" is a bad idea... Of course that's another possibility, to use that on your 5DIII (or on an APS-C camera where it would "act like" 240-960mm... which might even be "too long"... difficult to work with).

However, the Tamron lens will be bigger and heavier than a 300mm f/4 + 1.4X. It also won't be nearly as well built or sealed for dust/weather resistance as a Canon L-series lens (and the equally well built Canon teleconverters). There is a more robustly built Sigma 150-600mm "Sport" (S) lens... but it's even bigger and heavier yet. It's close to double the weight of a Canon 300mm f/4 and 1.4X.

Another lens to consider is the Canon 100-400mm f/4.5-5.6L IS USM "II"... it's superb. I'm getting ready to go shoot a sporting event right now, where I'm sure I'll use mine a lot. It works well, too, with 1.4X II teleconverter (though I rarely need it.... I am using the 100-400 on an APS-C camera where it has plenty of "reach" for many purposes).

MountainDave

Before buying anything, I suggest googling pro reviews of all the candidates on your list. I own a 300 f/4L IS plus the 100-400L IS II. I use both with a 1.4X III as well. The 300 is certainly capable of exquisite images and like most primes is really sharp. But, I'm going to plug the 100-400. I have seven L series lenses and this is my favorite. It's the favorite of a lot of users. Outstanding IQ is a given. I shoot almost entirely handheld and the IS is so good, I get sharp shots at 1/40. Like most modern Canon lenses, the AF performs great. This is an area where 3rd party lenses often come up short in comparisons. Often overlooked is the 3.25 ft. MFD which allows closeups of flowers, bugs, small animals, etc. that other long lenses simply cannot do. I've had occasions where I've taken distant portraits that came out surprisingly beautiful too considering that's not really what it is designed for. Plus, it renders beautiful colors. Finally, it is smooth, quiet and built like a tank.

Danielmb

Image Master's recommendations are spot on. I have similar setup and no complaints.

BBurns Loc: South Bay, California

You did not state the brand of the doubler.
Should we presume it is Canon or something else?
If not, that will make a huge difference.

Blair Shaw Jr Loc: Dunnellon,Florida

IBE

Thank everyone for your valuable opinions

PHRubin Loc: Nashville TN USA

I have the Tamron 150-600 G2 and am very happy with it. However, I am not as critical as some users. I have a Sigma 18-300 as my most used lens. I did not calibrate it, but shoot in live view so calibration of focus cannot be an issue.

BamaTexan Loc: Deep in the heart of Texas

My 100-400 IS II Canon is the best lens I have ever owned!!

Photocraig

Before I did that I'd substitute a 1.4 extender with the 300. It would give you a 420mm reach with a max aperture of f4. How's the 5.6 Aperture hampering focus on the Mark III? At least the center focus point should be a cross type focusing down to 5.6. If I were to trade anything, I think I'd look at a newer body while you can get something for the Mark III.

saxman71 Loc: Wenatchee, WA

I think you should keep the 300mm AND buy the Tamron 150x600mm G2. You can't have too much equipment.