In-Depth Review: Tamron 150-600 f/5-6.3 VC

[AlanF]

Which would be sharper, this Tamron zoom (at 560mm), or a Canon 400 f/4L DO + 1.4TC at 560mm (either a ii or iii TC)?

I know that particular Canon is supposed to be less contrasty because it's a "DO" but it's not supposed to be soft...it's supposed to be fairly high in resolution. The images I've seen from it, look extremely sharp to me...far sharper than the 100-400L. And none have lacked any contrast that I would want to add to.

Just debating whether to rent a 400 DO...they intrigue me. It weighs about the same as this Tamron...and is f/4 at 400mm, rather than f/5.6. I know it costs a lot more, but used (and refurb) prices have been known to dip down quite a bit below the full retail (might even get below $4k sometime). And it can be rented for 4 days for around $200.

It gets a pretty scathing review by TDP http://www.the-digital-picture.com/Reviews/Canon-EF-400mm-f-4.0-DO-IS-USM-Lens-Review.aspx

The image quality with 1.4x TC looks poor there.

I don't see the "scathing" part of the review. Also don't see a sample where it's combined with a TC.

Bryan usually writes about lenses in glowing praise. But this is what he writes about the 400/4 DO, quote:

"The apparent sharpness of this lens is not in direct relation to its price. The Canon EF 400mm f/4 DO IS USM Lens is reasonably sharp at f/4 and very sharp when stopped down to f/5.6. But it is not as sharp as the Canon EF 300mm f/2.8 L IS Lens (few lenses are). The 300mm f/2.8 L IS with a Canon 1.4x Extender attached (yielding a heavier but less expensive 420mm f/4 IS lens) is similar to the 400 in sharpness. The Canon EF 500mm f/4 IS L Lens is sharper as well (similarly priced but nearly twice as heavy). The much smaller, lighter, slower (max aperture) and far less expensive Canon EF 400mm f/5.6 L Lens and Canon EF 100-400mm f/4.5-5.6 L IS Lens compete very well with the DO in sharpness at f/5.6 and are even sharper in the corners (and one of them is a zoom).

Contrast is the Canon EF 400mm f/4 DO IS USM Lens' optical shortcoming - which also hurts the apparent sharpness performance. I found that most of my shots needed a healthy contrast boost in post-processing (or a positive in-camera contrast setting). I could easily tell which image was taken with the 400 DO when looking at comparative shots on a monitor. The 300 f/2.8 IS has much better contrast than the 400 DO. Even the Canon 100-400mm L has better contrast when the vignetting in the full frame corners at 400mm does not get in the way. Low contrast is my most-significant disapointment with the 400 DO - fortunately it is something that post-processing can help."

(Note the comparison with the 300mm f/2.8 is with the less sharp series I lens, which does not take 1.4xTC as well as the series II does).

And, here is a direct comparison of the 400mm DO with a 1.4xTC vs the 400mm f/5.6 at 560mm, with the DO stopped down to the same f/8 of the older lens. The 400mm f/5.6 is significantly sharper

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=338&Camera=453&Sample=0&FLI=3&API=3&LensComp=278&CameraComp=453&SampleComp=0&FLIComp=3&APIComp=1

 

[TWI by Dustin Abbott]

Bryan's chart for comparing lens sharpness is one of the best tools of its type I have seen. He invests a lot of time and effort in those, but it is certainly one of the most valuable resources on the net for adding a visual component to the raw numbers that most sites post.

There are a few exceptions where it seems like he may have not had a copy of the lens that performs as well as the mean, but for the most part it tells the story pretty well.

 

[dcm]

...

Excellent review.

I am definitely putting this lens on my shopping list. An extra 200mm over the 100-400 is just what I could use for bird photography.

That extra 200mm certainly makes a difference. I haven't really shot the lens on a crop much (other than the M :), but the reach on a 70D/7D would be amazing.

...

So what was your experience with the Tamron on the EOS M?

 

[CarlTN]

Which would be sharper, this Tamron zoom (at 560mm), or a Canon 400 f/4L DO + 1.4TC at 560mm (either a ii or iii TC)?

I know that particular Canon is supposed to be less contrasty because it's a "DO" but it's not supposed to be soft...it's supposed to be fairly high in resolution. The images I've seen from it, look extremely sharp to me...far sharper than the 100-400L. And none have lacked any contrast that I would want to add to.

Just debating whether to rent a 400 DO...they intrigue me. It weighs about the same as this Tamron...and is f/4 at 400mm, rather than f/5.6. I know it costs a lot more, but used (and refurb) prices have been known to dip down quite a bit below the full retail (might even get below $4k sometime). And it can be rented for 4 days for around $200.

It gets a pretty scathing review by TDP http://www.the-digital-picture.com/Reviews/Canon-EF-400mm-f-4.0-DO-IS-USM-Lens-Review.aspx

The image quality with 1.4x TC looks poor there.

I don't see the "scathing" part of the review. Also don't see a sample where it's combined with a TC.

Bryan usually writes about lenses in glowing praise. But this is what he writes about the 400/4 DO, quote:

"The apparent sharpness of this lens is not in direct relation to its price. The Canon EF 400mm f/4 DO IS USM Lens is reasonably sharp at f/4 and very sharp when stopped down to f/5.6. But it is not as sharp as the Canon EF 300mm f/2.8 L IS Lens (few lenses are). The 300mm f/2.8 L IS with a Canon 1.4x Extender attached (yielding a heavier but less expensive 420mm f/4 IS lens) is similar to the 400 in sharpness. The Canon EF 500mm f/4 IS L Lens is sharper as well (similarly priced but nearly twice as heavy). The much smaller, lighter, slower (max aperture) and far less expensive Canon EF 400mm f/5.6 L Lens and Canon EF 100-400mm f/4.5-5.6 L IS Lens compete very well with the DO in sharpness at f/5.6 and are even sharper in the corners (and one of them is a zoom).

Contrast is the Canon EF 400mm f/4 DO IS USM Lens' optical shortcoming - which also hurts the apparent sharpness performance. I found that most of my shots needed a healthy contrast boost in post-processing (or a positive in-camera contrast setting). I could easily tell which image was taken with the 400 DO when looking at comparative shots on a monitor. The 300 f/2.8 IS has much better contrast than the 400 DO. Even the Canon 100-400mm L has better contrast when the vignetting in the full frame corners at 400mm does not get in the way. Low contrast is my most-significant disapointment with the 400 DO - fortunately it is something that post-processing can help."

(Note the comparison with the 300mm f/2.8 is with the less sharp series I lens, which does not take 1.4xTC as well as the series II does).

And, here is a direct comparison of the 400mm DO with a 1.4xTC vs the 400mm f/5.6 at 560mm, with the DO stopped down to the same f/8 of the older lens. The 400mm f/5.6 is significantly sharper

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=338&Camera=453&Sample=0&FLI=3&API=3&LensComp=278&CameraComp=453&SampleComp=0&FLIComp=3&APIComp=1

Good point, but the 400 f/5.6 is a native f/8 lens with this combination...not something I can or would want to use. Also it doesn't have IS...

I'll grant you though, I still have yet to find really great samples done with the 400 DO, other than the few that have been posted on here. After looking at pbase.com a bit, most of the images were done with older Rebels and 20D's...not exactly a good measuring stick.

 

[mackguyver]

Good point, but the 400 f/5.6 is a native f/8 lens with this combination...not something I can or would want to use. Also it doesn't have IS...

I'll grant you though, I still have yet to find really great samples done with the 400 DO, other than the few that have been posted on here. After looking at pbase.com a bit, most of the images were done with older Rebels and 20D's...not exactly a good measuring stick.

Staying off topic here , I was a bit torn between the DO and the 300 2.8 IS II given their similar price, size, and weight, but went for the 300 because it's newer, sharper, takes TCs better, and has newer IS. IS was the main reason for my upgrade over the 400 5.6, so the latest generation IS was one of my biggest factors. I don't love the way it jumps in the 300 in mode 2, but it is amazing in practice, and mode 3 is mighty nice.

 

[CarlTN]

Good point, but the 400 f/5.6 is a native f/8 lens with this combination...not something I can or would want to use. Also it doesn't have IS...

I'll grant you though, I still have yet to find really great samples done with the 400 DO, other than the few that have been posted on here. After looking at pbase.com a bit, most of the images were done with older Rebels and 20D's...not exactly a good measuring stick.

Staying off topic here , I was a bit torn between the DO and the 300 2.8 IS II given their similar price, size, and weight, but went for the 300 because it's newer, sharper, takes TCs better, and has newer IS. IS was the main reason for my upgrade over the 400 5.6, so the latest generation IS was one of my biggest factors. I don't love the way it jumps in the 300 in mode 2, but it is amazing in practice, and mode 3 is mighty nice.

No doubt about that. If I were in your shoes I would have done the same. I already know how amazing the new 300 is, so I don't feel that much of a need to even try one (at least not to confirm how good it is...making use of it would be fun though). The more interesting and lesser known question for me though, is how good (or bad) is the older 400. I rented the older 500 f/4 in 2011, and was very disappointed with it...it was a lot less sharp at 500mm than even my Sigma 120-400 is at 400mm (although it is actually every bit as sharp as the Canon 100-400L, so it's no slouch). The 500 definitely had better color and contrast than my Sigma does at 400mm (not when it's wider than 200mm though...the Sigma is world class there), but the 500 was just plain soft. I suspect it was probably very worn out, maybe the focusing mechanism or attachments to those elements perhaps was not keeping them in critical alignment or something (I can only guess)...because I know even that older generation of the 500 f/4 was supposed to be quite sharp. The one I rented was not (even with manual live view focus with mirror lock on a tripod and very high shutter speeds).

As for this going "off topic", sorry about that...but I feel comparisons between other lenses in this range, is actually not that far off topic.

The reason I feel this new Tamron appears to be not all that appealing, is because it seems to get softer as it goes past 400mm...but going past 400mm is really the whole reason to buy this lens. If you're going to buy it and shoot more of the time below 400mm, there are better, smaller lenses for that (such as the lighter and less costly Sigma...or the significantly lighter, smaller 70-300L at a slightly higher price point). I guess what I'm saying is, maybe the best image quality at the longest focal length with this new Tamron, looks like it's at 400mm, or slightly past it...but not at 600mm.

That's not to say it's not good value for money...but if you want to get maximum IQ for the money past 400mm, it might not be the best choice.

 

[mackguyver]

The reason I feel this new Tamron appears to be not all that appealing, is because it seems to get softer as it goes past 400mm...but going past 400mm is really the whole reason to buy this lens. If you're going to buy it and shoot more of the time below 400mm, there are better, smaller lenses for that (such as the lighter and less costly Sigma...or the significantly lighter, smaller 70-300L at a slightly higher price point). I guess what I'm saying is, maybe the best image quality at the longest focal length with this new Tamron, looks like it's at 400mm, or slightly past it...but not at 600mm.

That's not to say it's not good value for money...but if you want to get maximum IQ for the money past 400mm, it might not be the best choice.

I'm with you on that one, and other than the 70-300L and 200-400 1.4x, it seems that nearly all of these lenses lose a lot of sharpness at their maximum focal length. I don't get that because the whole idea is to shoot at or near the max FL. Who buys a 150-600 to primarily shoot at 150-300? It seems like the lens designers would optimize for 400-600 at the expense of 150-400, but I'm sure that's neither easy nor cheap

 

[TWI by Dustin Abbott]

...

Excellent review.

I am definitely putting this lens on my shopping list. An extra 200mm over the 100-400 is just what I could use for bird photography.

That extra 200mm certainly makes a difference. I haven't really shot the lens on a crop much (other than the M :), but the reach on a 70D/7D would be amazing.

...

So what was your experience with the Tamron on the EOS M?

It's mostly about logistics. The M is so small that the balance is really weird, as is trying to operate the camera with such a small grip. It would be better on a monopod or tripod, obviously. As this pictures shows, it is very much a case of the "tail wagging the dog" ;D

 

[CarlTN]

The reason I feel this new Tamron appears to be not all that appealing, is because it seems to get softer as it goes past 400mm...but going past 400mm is really the whole reason to buy this lens. If you're going to buy it and shoot more of the time below 400mm, there are better, smaller lenses for that (such as the lighter and less costly Sigma...or the significantly lighter, smaller 70-300L at a slightly higher price point). I guess what I'm saying is, maybe the best image quality at the longest focal length with this new Tamron, looks like it's at 400mm, or slightly past it...but not at 600mm.

That's not to say it's not good value for money...but if you want to get maximum IQ for the money past 400mm, it might not be the best choice.

I'm with you on that one, and other than the 70-300L and 200-400 1.4x, it seems that nearly all of these lenses lose a lot of sharpness at their maximum focal length. I don't get that because the whole idea is to shoot at or near the max FL. Who buys a 150-600 to primarily shoot at 150-300? It seems like the lens designers would optimize for 400-600 at the expense of 150-400, but I'm sure that's neither easy nor cheap

Exactly...frankly I suspect it might not even be possible to produce a "super-telephoto" zoom lens that reaches or maintains maximum sharpness at its longest focal length. I don't even think the Canon 200-400 is at its best at 400mm, but I could be wrong. From what I recall of Canon's own MTF chart, it appeared the maximum sharpness was toward the wide end, but with the internal TC switched in. I might be remembering wrong...

I do wish Canon would produce a less costly line of lenses with an internal TC...

 

[CarlTN]

...

Excellent review.

I am definitely putting this lens on my shopping list. An extra 200mm over the 100-400 is just what I could use for bird photography.

That extra 200mm certainly makes a difference. I haven't really shot the lens on a crop much (other than the M :), but the reach on a 70D/7D would be amazing.

...

So what was your experience with the Tamron on the EOS M?

It's mostly about logistics. The M is so small that the balance is really weird, as is trying to operate the camera with such a small grip. It would be better on a monopod or tripod, obviously. As this pictures shows, it is very much a case of the "tail wagging the dog" ;D

Is that a camera, or a rear lens cap on there?

 

[TWI by Dustin Abbott]

...

Excellent review.

I am definitely putting this lens on my shopping list. An extra 200mm over the 100-400 is just what I could use for bird photography.

That extra 200mm certainly makes a difference. I haven't really shot the lens on a crop much (other than the M :), but the reach on a 70D/7D would be amazing.

...

So what was your experience with the Tamron on the EOS M?

It's mostly about logistics. The M is so small that the balance is really weird, as is trying to operate the camera with such a small grip. It would be better on a monopod or tripod, obviously. As this pictures shows, it is very much a case of the "tail wagging the dog" ;D

Is that a camera, or a rear lens cap on there?

Exactly. Pictures look fine, but logistics are pretty brutal.

 

[dcm]

...

Excellent review.

I am definitely putting this lens on my shopping list. An extra 200mm over the 100-400 is just what I could use for bird photography.

That extra 200mm certainly makes a difference. I haven't really shot the lens on a crop much (other than the M :), but the reach on a 70D/7D would be amazing.

...

So what was your experience with the Tamron on the EOS M?

It's mostly about logistics. The M is so small that the balance is really weird, as is trying to operate the camera with such a small grip. It would be better on a monopod or tripod, obviously. As this pictures shows, it is very much a case of the "tail wagging the dog" ;D

Is that a camera, or a rear lens cap on there?

Exactly. Pictures look fine, but logistics are pretty brutal.

Thanks for the photo. That's quite an extension from the tripod foot on the lens. Thought that might be the case, not really hand hold-able due to LiveView and the small body. A tripod or a shoulder mount like a BushHawk seem like the way to go with the M.

 

[Drizzt321]

The reason I feel this new Tamron appears to be not all that appealing, is because it seems to get softer as it goes past 400mm...but going past 400mm is really the whole reason to buy this lens. If you're going to buy it and shoot more of the time below 400mm, there are better, smaller lenses for that (such as the lighter and less costly Sigma...or the significantly lighter, smaller 70-300L at a slightly higher price point). I guess what I'm saying is, maybe the best image quality at the longest focal length with this new Tamron, looks like it's at 400mm, or slightly past it...but not at 600mm.

That's not to say it's not good value for money...but if you want to get maximum IQ for the money past 400mm, it might not be the best choice.

I'm with you on that one, and other than the 70-300L and 200-400 1.4x, it seems that nearly all of these lenses lose a lot of sharpness at their maximum focal length. I don't get that because the whole idea is to shoot at or near the max FL. Who buys a 150-600 to primarily shoot at 150-300? It seems like the lens designers would optimize for 400-600 at the expense of 150-400, but I'm sure that's neither easy nor cheap

I dunno. I may want to often shoot in the 400+ FL, but right now my longest lens is the 135L, so I suspect I'd find myself shooting a lot from the 200+ with it. And after I eventually get the 70-200, I'll still probably be shooting more in the 200+, or more likely the 300+ when I do shoot with this Tamron. For me it's that (right now) I can't see myself shooting really any of these focal lengths all that regularly, or even if I do I somehow don't see myself spending $7K+ on the BWL lenses, with or without 1.4x/2x TCs. Not to say when I win the lotto I won't be buying myself the LensRentals Chess set, but other than that very fortuitous situation, for me at least, the BWL aren't something I'll be buying.

This lens is really for the crowd that want's a flexible lens, fairly decent optical quality, at what's really an amazing price. Heck, if this were another $300-500 more it'd still be a good price for what you get, although obviously not as great of a deal. So me or people who want a cheap birding lens would find the fairly good (although not great) IQ worth the price. Not to say I don't want maximum IQ, but if you want maximum IQ this lens isn't targeting you anyway.

 

[candc]

i wish mine would hurry up and get here so i could tell you what it is really like instead of what i think it will do. til then i can say that i have downloaded all the samples and read all the reviews. i agree with what Drizzt321 is saying but it also appeals to another crowd as a secondary lens, i have the sigma 120-300 sport which is amazingly sharp and heavy. its really good with the 1.4tc, 2x meh? from what i have seen its about the same as this new tamron at 600? i plan on getting the 600ii because i like to shoot that fl and its the best i have seen, are you going to go for a walk on the beach with the sigma 120-300 and the 600ii? this lens covers that whole range pretty well in a nice relatively light package no tc's no changing lenses

 

[CarlTN]

The reason I feel this new Tamron appears to be not all that appealing, is because it seems to get softer as it goes past 400mm...but going past 400mm is really the whole reason to buy this lens. If you're going to buy it and shoot more of the time below 400mm, there are better, smaller lenses for that (such as the lighter and less costly Sigma...or the significantly lighter, smaller 70-300L at a slightly higher price point). I guess what I'm saying is, maybe the best image quality at the longest focal length with this new Tamron, looks like it's at 400mm, or slightly past it...but not at 600mm.

That's not to say it's not good value for money...but if you want to get maximum IQ for the money past 400mm, it might not be the best choice.

I'm with you on that one, and other than the 70-300L and 200-400 1.4x, it seems that nearly all of these lenses lose a lot of sharpness at their maximum focal length. I don't get that because the whole idea is to shoot at or near the max FL. Who buys a 150-600 to primarily shoot at 150-300? It seems like the lens designers would optimize for 400-600 at the expense of 150-400, but I'm sure that's neither easy nor cheap

I dunno. I may want to often shoot in the 400+ FL, but right now my longest lens is the 135L, so I suspect I'd find myself shooting a lot from the 200+ with it. And after I eventually get the 70-200, I'll still probably be shooting more in the 200+, or more likely the 300+ when I do shoot with this Tamron. For me it's that (right now) I can't see myself shooting really any of these focal lengths all that regularly, or even if I do I somehow don't see myself spending $7K+ on the BWL lenses, with or without 1.4x/2x TCs. Not to say when I win the lotto I won't be buying myself the LensRentals Chess set, but other than that very fortuitous situation, for me at least, the BWL aren't something I'll be buying.

This lens is really for the crowd that want's a flexible lens, fairly decent optical quality, at what's really an amazing price. Heck, if this were another $300-500 more it'd still be a good price for what you get, although obviously not as great of a deal. So me or people who want a cheap birding lens would find the fairly good (although not great) IQ worth the price. Not to say I don't want maximum IQ, but if you want maximum IQ this lens isn't targeting you anyway.

Good points. Again, my point is that if you want to shoot at or below 400mm, there are other lenses better suited, weigh less, have faster aperture at those shorter focal lengths...and in some cases cost less, yet deliver equal or higher IQ to this Tamron.

If the longest focal length you have now is 135mm, I have to wonder if you need any kind of telephoto lens at all? Because if you needed one, you would already have one. Btw, the TC's work superbly on the 135 f/2...although with the 2x one mounted, I kind of wish for a way to attach a tripod ring.

 

[CarlTN]

i wish mine would hurry up and get here so i could tell you what it is really like instead of what i think it will do. til then i can say that i have downloaded all the samples and read all the reviews. i agree with what Drizzt321 is saying but it also appeals to another crowd as a secondary lens, i have the sigma 120-300 sport which is amazingly sharp and heavy. its really good with the 1.4tc, 2x meh? from what i have seen its about the same as this new tamron at 600? i plan on getting the 600ii because i like to shoot that fl and its the best i have seen, are you going to go for a walk on the beach with the sigma 120-300 and the 600ii? this lens covers that whole range pretty well in a nice relatively light package no tc's no changing lenses

If you would let me borrow your Sigma 120-300, I would take it on however long of a walk you wish! I don't live on a beach or go on a vacation every 3 months...but I have lots of nice places near where I am to take wildlife photos.

 

[Drizzt321]

The reason I feel this new Tamron appears to be not all that appealing, is because it seems to get softer as it goes past 400mm...but going past 400mm is really the whole reason to buy this lens. If you're going to buy it and shoot more of the time below 400mm, there are better, smaller lenses for that (such as the lighter and less costly Sigma...or the significantly lighter, smaller 70-300L at a slightly higher price point). I guess what I'm saying is, maybe the best image quality at the longest focal length with this new Tamron, looks like it's at 400mm, or slightly past it...but not at 600mm.

That's not to say it's not good value for money...but if you want to get maximum IQ for the money past 400mm, it might not be the best choice.

I'm with you on that one, and other than the 70-300L and 200-400 1.4x, it seems that nearly all of these lenses lose a lot of sharpness at their maximum focal length. I don't get that because the whole idea is to shoot at or near the max FL. Who buys a 150-600 to primarily shoot at 150-300? It seems like the lens designers would optimize for 400-600 at the expense of 150-400, but I'm sure that's neither easy nor cheap

I dunno. I may want to often shoot in the 400+ FL, but right now my longest lens is the 135L, so I suspect I'd find myself shooting a lot from the 200+ with it. And after I eventually get the 70-200, I'll still probably be shooting more in the 200+, or more likely the 300+ when I do shoot with this Tamron. For me it's that (right now) I can't see myself shooting really any of these focal lengths all that regularly, or even if I do I somehow don't see myself spending $7K+ on the BWL lenses, with or without 1.4x/2x TCs. Not to say when I win the lotto I won't be buying myself the LensRentals Chess set, but other than that very fortuitous situation, for me at least, the BWL aren't something I'll be buying.

This lens is really for the crowd that want's a flexible lens, fairly decent optical quality, at what's really an amazing price. Heck, if this were another $300-500 more it'd still be a good price for what you get, although obviously not as great of a deal. So me or people who want a cheap birding lens would find the fairly good (although not great) IQ worth the price. Not to say I don't want maximum IQ, but if you want maximum IQ this lens isn't targeting you anyway.

Good points. Again, my point is that if you want to shoot at or below 400mm, there are other lenses better suited, weigh less, have faster aperture at those shorter focal lengths...and in some cases cost less, yet deliver equal or higher IQ to this Tamron.

If the longest focal length you have now is 135mm, I have to wonder if you need any kind of telephoto lens at all? Because if you needed one, you would already have one. Btw, the TC's work superbly on the 135 f/2...although with the 2x one mounted, I kind of wish for a way to attach a tripod ring.

It's really a matter of money and priorities. Burning Man, great wine, or a new lens that's $2k+ (70-200 f/2.8 IS v2)? It's a lot easier to spend a few hundred $$ now than save it up for a single large purchase. At least for me. I have been slowly saving up for that, but I just gotta go ahead and stop buying wine or going out and eating so well. I have thought about getting a TC, and I suppose the 1.4x would be good for a lot of indoor shooting, but otherwise where I want more FL it's when I'm out on the beach trying to get the surfers or pelicans flying along the water, and 400mm is decent, but going out to 600mm would be even nicer.

 

[TWI by Dustin Abbott]

I can't speak for everyone, but I own multiple teleconverters and frankly I kind of hate using them. In the field or at an event, I often don't bother with changing it out because of the environment, the amount of time for the switch, or the risk of getting gunk in my body during the change. The 135L takes a 1.4x quite well, and I do use that combination, but let's be realistic; it is only 189mm, and an unstabilized 189mm at that.

The 70-200L II takes teles very well well, too, but even on it with a 2x there is quite a degrading of image quality, and it is a 400mm f/5.6 by that point.

If you want reach, the Tamron is the best bargain option on the market. I'll certainly be adding one to my kit. And for those saying it is only good up to 400mm - they haven't used it. I thought I was taking this wide open, but it is actually f/7.1 (stopped down 1/3rd a stop). But it is 600mm, handheld, and ISO 2000. How exactly is this not usable?

 

[Don Haines]

I can't speak for everyone, but I own multiple teleconverters and frankly I kind of hate using them. In the field or at an event, I often don't bother with changing it out because of the environment, the amount of time for the switch, or the risk of getting gunk in my body during the change. The 135L takes a 1.4x quite well, and I do use that combination, but let's be realistic; it is only 189mm, and an unstabilized 189mm at that.

The 70-200L II takes teles very well well, too, but even on it with a 2x there is quite a degrading of image quality, and it is a 400mm f/5.6 by that point.

If you want reach, the Tamron is the best bargain option on the market. I'll certainly be adding one to my kit. And for those saying it is only good up to 400mm - they haven't used it. I thought I was taking this wide open, but it is actually f/7.1 (stopped down 1/3rd a stop). But it is 600mm, handheld, and ISO 2000. How exactly is this not usable?

and to help prove the point.... this is the centre quarter of an image taken at 552mm... F6.3, 1/800th second, ISO320, handheld with a 60D.

The second picture is taken at sunset, 600mm, F6.3, 1/640 second, ISO320, handheld with a 60D

 

[candc]

I can't speak for everyone, but I own multiple teleconverters and frankly I kind of hate using them. In the field or at an event, I often don't bother with changing it out because of the environment, the amount of time for the switch, or the risk of getting gunk in my body during the change. The 135L takes a 1.4x quite well, and I do use that combination, but let's be realistic; it is only 189mm, and an unstabilized 189mm at that.

The 70-200L II takes teles very well well, too, but even on it with a 2x there is quite a degrading of image quality, and it is a 400mm f/5.6 by that point.

If you want reach, the Tamron is the best bargain option on the market. I'll certainly be adding one to my kit. And for those saying it is only good up to 400mm - they haven't used it. I thought I was taking this wide open, but it is actually f/7.1 (stopped down 1/3rd a stop). But it is 600mm, handheld, and ISO 2000. How exactly is this not usable?

It is not usable because images such as this are banned on cr by the OSP (Obscene Squirrel Police)

Reference.
http://www.canonrumors.com/forum/index.php?topic=15358.45
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