Posted by Rod Barbee on February 26, 2007 at 4:00 PM
It depends on the brand and what camera system you have. Generally speaking, if you stick with your camera manufacturer's teleconverter, you'll do ok.
I shoot Nikon and use their TC14e teleconverter. It's very good and I get great results using it on a 70 or 80-200 f/2.8 zoom, a 300 f/4 or f/2.8, and 500 or 600mm lenses. It's also about $400-500.
This particular converter won't fit on Nikon's lower end zooms though, like the 70-300. And it's my opinion that the teleconverters that will fit on that type of lens aren't of the highest quality anyway. Besides, putting a teleconverter on a variable aperture lens like that 70-300 would result in effective apertures in the f/8 range, which is too slow and makes for iffy, if not impossible, autofocus.
so, if you have a quality constant aperture zoom (like an 80-200 f/2.8) or a good prime (like a 300 f/2.8 or 300 f/4, or 500+f/4) and you get the manufacturer's recommended teleconverter, you'll have good quality.
If you opt for an inexpensive 3rd party teleconverter you'll likely get what you pay for.
The teleconverters allow to multiply the focal length by 1.4x or 2x, and they are a great help for wildlife photography. That said, they have both pros and cons, and you need to know them well to get good results.
A teleconverter is essentially an optical system that magnifies the central portion of the image captured by the lens. The practical result is that you get more magnification, but you lose a little of sharpness and 1 or 2 stops of light. If you want to get good photos using a teleconverter, you have to couple it with a good lens, that has "sharpness to spare": if you add a TC to a zoom lens, the image quality is excessively degraded. Even top quality zoom lenses, as the 70-200 f/2.8, gives poor results with the TC.
The 1.4x TC is widely considered the best TC, because it doesn't reduce too much the image quality. You can use it to transform a 300mm f/2.8 into a 420mm f/4, or a 600mm f/4 into a 840mm f/5.6. You lose one stop of light, but the sharpness remains very good even of the widest aperture.
The 2.0x TC is more controversial. You can use it to transform a 300mm f/2.8 into a 600mm f/5.6, or a 600 f/4 into a 1200 f/8. The increase of magnification is huge, but you lose two stops of light. Remember that all Canon cameras, except the 1 series bodies, will autofocus only with an effective aperture of f/5.6 or brighter, so if your lens becomes an f/8 you lose AF.
An even more pressing issue is the loss of sharpness. I do not recommend to shoot wide open when you use a 2x TC, unless it is strictly necessary, because there is a noticeable softening. Even a top quality lens as the Canon 600 f/4 IS, when used with the 2x TC, is a bit soft wide open (i.e. at f/8). On the other hand, if you stop down by 1 or 2 stop (i.e. to f11 or f16, with 600 IS + 2X) you get a good sharpness.
I'd suggest to use the 2x TC when you really need the maximum reach and there is enough light to stop down to f/11.
The teleconverters does not change the minimum focusing distance: for example, the 600 f/4 has a focusing distance of 5.5 meters, and if you add the 2x TC it becomes a 1200 f/8 with the same focusing distance of 5.5 mt. This is a great plus for small subjects: with the bare 600 you have a macro ratio of 0.12x, with the 2x you get 0.24x, i.e. 1:4. This is an excellent magnification for small birds, butterflies and flowers.
The depth of field depends by the actual (effective) aperture. A 300 f/2.8 + 2x becomes a 600 f/5.6, and when you use it wide open you get exactly the same depth of field of a 600 f/5.6 (not the depth of field of f/2.8).
Posted by Mitch Erwin on February 26, 2007 at 4:05 PM
Hi Kyle,
I have a 2x Canon that I use " some " on a 100 - 400 IS lens. The focal length it adds is wonderful but, sharpness is lacking more and you must manually focus, which is a real drawback if you are panning. I've seen several captures taken by all of the wonderful photographers on here using 1.4X and 2Xs. Usually with Canon L prime telephoto lenses. Personally I would not recommend one on the above mentioned lens if you are shooting with a Canon system. I'm sure you'll get several other thoughts on using teleconverters.
This is not a grump, but an offer of more help that you are likely to get in a singel thread. Every few months since the start of the site there has been question much like yours. People come and go here, plus most tend not to respond if they've answered the same question a time or two. There are also new models cropping up, so a new post isn't unreasonable, but it's a really good idea to use the search function to recover comments from the past.
To prove this isn't a grump, I'll go ahead and answer your question in general terms, since it's a general question. Almost without exception it is best to follow the recommendation of your lens manufacturer and to stick with TCs made by the same lens maker for your specific lens.
Within that, there are simply some combos that work better than others. A TC on a 300 f/2.8 is likely to give better results than the same TC even if it's also recommended for a 70-300. There are quality differences between lenses, and a TC may tend to exaggerate issues with lower priced lenses.
There's also the question of TC "power." In general a 1.4x is going to give better results than a 2x, while a 1.7x might be a reasonable compromise if you really want more power than a 1.4x.
TC's also may require you to use a steadier tripod and head to help dampen vibration, which is much more problematic as lenses stretch, whether they are actually longer or you add a TC. With really long lenses plus a TC you might even have to add aftermarket braces, as I feel is necessary with my Nikon 500 f/4 and a 2x. Kirk makes a brace that extends support on the lens and TC, dramatically improving its performance.
Then there's the question of technique. As magnification goes up, issues like shutter movement, mirror movement and vibraton from your hand on the shutter release can degrade image quality. You have to develop a strategy and perhaps buy a cable release to get around them.
Is this a help? Hopefully you read past the first paragraph so I could prove that I'm not grumpy about your question!!!!!
Posted by John W. Wall on February 26, 2007 at 4:36 PM
I use a 1.7X with a 300/4 AF-S (Nikon) that works great. The 2X is a much longer lens and made things slightly more unwieldy.
Posted by Ed Cordes on February 26, 2007 at 7:57 PM
I have both the 1.4 and 2 X TC from Canon. I use them as described by Juza on my 500 L IS with good results. The 1.4 shows very little, if any, loss of sharpness. The 2 X needs to be handled well. I also use a 1 series camera so focusing at f8 is an option, although the center point only.
My 100-400 L does not fare so well even though Canon says it is OK. I quit using any TC on this lens. I think Juza's comment re "sharpness to spare" is a very valid point.
Posted by Steve Foss on February 26, 2007 at 9:26 PM
I started out with the 100-400L and a Canon 1.4 TC. Now, when shooting that lens, I never take the TC out of the bag. Loss of autofocus and IQ degradation are too nasty a combo for me to overcome in most situations.
Posted by William Lloyd on February 27, 2007 at 12:19 AM
Yes, it's as everyone says - I suspect Canon have sold many a 400 f/5.6 lens to people who already own a 100-400 IS lens, because the Extenders just don't do well on that lens. At least, that's why I bought one! I gave up using my 2X until I was able to afford a 600 f/4.0IS lens, the 1.4EX is much more forgiving on lens quality.
Posted by Ott Luuk on February 27, 2007 at 3:42 AM
I`m currently trying out Canon`s 1.4x on the 400/5.6L. The added reach is excellent, even on a film camera. But the main lesson I´ve learned is that it`s way harder to use the 560/8 combo than the bare lens. You lose AF, the viewfinder gets darker, the lens gets longer and heavier... not good for handholding and even on tripod, vibrations are visibly increased. That`s what you get with a lightweight, physically long, high magnification lens. f/8 is very often too slow for stopping action.
I`m still happy with the purchase of the TC because I was aware of the basic drawbacks. When the light is right and the subject calls for it, I have no hesitation to use the TC, with the lens wide open, if needed. I consider it a useful accessory, not a way to turn my lens permanently into a 560/8.
IMO, if you already have a high quality prime telephoto, a 1.4x converter is a wise addition, especially, if the resulting combination is f/5.6 or faster. f/8 gets problematic but is usable. You may get away with 2x on fast sharp lenses like 300/2.8 or 400/2.8. It is advisable to use your lens manufacturer`s TC-s.
If you start with a 70-300/5.6 zoom, TC-s are a waste of money. With optically non-matching lenses, the results are going to be bad. You could get better quality by cropping and upsizing your images.
Posted by Rod Barbee on February 27, 2007 at 11:38 AM
With all respect to Juza's comprehensive post about teleconverters, I can say from experience that it is possible to get good results by using a quality TC with a quality zoom. In my experience, I have not seen excessive degredation when using a Nikon TC14e (or b) with a 70-200 or 80-200 f/2.8 lens. (unless I've used poor technique) Those lenses are very sharp to begin with and I've had terrific luck with combining them with that teleconverter.
Posted by Alex Lofquist on February 27, 2007 at 6:14 PM
If you have a chunk of "big glass" a 1.4X TC is definitely worthwhile having. I probably have a TC 14B on my 500 f/4 Nikkor most of the time. Recently I bought a TC14E for use with my 70-200 f/2.8 Nikkor just to have that extra reach when I don't carry my 300 f/4, or when I want the VR capability my other long lenses do not have.
Hi Kyle, Zuza is absolutely right in everything he said. That said, I have found that a 1.4 TC made by the OEM can produce good results on a zoom lens as long as it's an exceptionally good lens. I have used an OEM 1.4 TC on an OEM 100-400mm f2.8 with acceptable results but I'm starting with a superb zoom to begin with. But by comparison, the results I get with that TC in combination with my 400mm prime are that much better. However, when I try to use my 1.4 TC on a 110-400mm Sigma it's TERRIBLE !
On a positive note, you may not necessarily loose AF at effective apertures tighter than 5.6.
I don't know if all Canon cameras behave the same way, and I don't have a Canon, but my camera manufacturer claims the same thing, i.e. no AF below 5.6, but my particular camera has no problem focusing with the TC at an effective aperture of f8. So my point is try it ... you might get lucky.
Good luck
Bob
Posted by Will Webster on February 28, 2007 at 2:42 PM
I routinely use a Tamron SP 1.4x between my 20D and 300/4 IS, and have gotten some spectacular results. I've also followed birds flying by and never had the focus lock. I've used the same TC when travelling light with the 70-200/4 and been impressed with the results. I've never done a comparison between the SP and Canon's TC, though.
Posted by Buck Ward on February 28, 2007 at 8:38 PM
I can't tell a difference, subjectively, between pictures made with a Canon's 300 f2.8 IS alone, or with a 1.4tC or a 2.0TC. The sharpness of this lens is legendary and is not degraded by the Canon TCs (on a 1.6 crop camera, anyhow.). The first time I used the 2.0TC with Canon's 70-200 f2.8 IS, I was disappointed in the sharpness and I haven't used that combination since. The 1.4TC on the 70-200 f2.8 usually produces acceptable results, but I don't often use this combination .
Discussion
14 repliesI shoot Nikon and use their TC14e teleconverter. It's very good and I get great results using it on a 70 or 80-200 f/2.8 zoom, a 300 f/4 or f/2.8, and 500 or 600mm lenses. It's also about $400-500.
This particular converter won't fit on Nikon's lower end zooms though, like the 70-300. And it's my opinion that the teleconverters that will fit on that type of lens aren't of the highest quality anyway. Besides, putting a teleconverter on a variable aperture lens like that 70-300 would result in effective apertures in the f/8 range, which is too slow and makes for iffy, if not impossible, autofocus.
so, if you have a quality constant aperture zoom (like an 80-200 f/2.8) or a good prime (like a 300 f/2.8 or 300 f/4, or 500+f/4) and you get the manufacturer's recommended teleconverter, you'll have good quality.
If you opt for an inexpensive 3rd party teleconverter you'll likely get what you pay for.
A teleconverter is essentially an optical system that magnifies the central portion of the image captured by the lens. The practical result is that you get more magnification, but you lose a little of sharpness and 1 or 2 stops of light. If you want to get good photos using a teleconverter, you have to couple it with a good lens, that has "sharpness to spare": if you add a TC to a zoom lens, the image quality is excessively degraded. Even top quality zoom lenses, as the 70-200 f/2.8, gives poor results with the TC.
The 1.4x TC is widely considered the best TC, because it doesn't reduce too much the image quality. You can use it to transform a 300mm f/2.8 into a 420mm f/4, or a 600mm f/4 into a 840mm f/5.6. You lose one stop of light, but the sharpness remains very good even of the widest aperture.
The 2.0x TC is more controversial. You can use it to transform a 300mm f/2.8 into a 600mm f/5.6, or a 600 f/4 into a 1200 f/8. The increase of magnification is huge, but you lose two stops of light. Remember that all Canon cameras, except the 1 series bodies, will autofocus only with an effective aperture of f/5.6 or brighter, so if your lens becomes an f/8 you lose AF.
An even more pressing issue is the loss of sharpness. I do not recommend to shoot wide open when you use a 2x TC, unless it is strictly necessary, because there is a noticeable softening. Even a top quality lens as the Canon 600 f/4 IS, when used with the 2x TC, is a bit soft wide open (i.e. at f/8). On the other hand, if you stop down by 1 or 2 stop (i.e. to f11 or f16, with 600 IS + 2X) you get a good sharpness.
I'd suggest to use the 2x TC when you really need the maximum reach and there is enough light to stop down to f/11.
The teleconverters does not change the minimum focusing distance: for example, the 600 f/4 has a focusing distance of 5.5 meters, and if you add the 2x TC it becomes a 1200 f/8 with the same focusing distance of 5.5 mt. This is a great plus for small subjects: with the bare 600 you have a macro ratio of 0.12x, with the 2x you get 0.24x, i.e. 1:4. This is an excellent magnification for small birds, butterflies and flowers.
The depth of field depends by the actual (effective) aperture. A 300 f/2.8 + 2x becomes a 600 f/5.6, and when you use it wide open you get exactly the same depth of field of a 600 f/5.6 (not the depth of field of f/2.8).
I have a 2x Canon that I use " some " on a 100 - 400 IS lens. The focal length it adds is wonderful but, sharpness is lacking more and you must manually focus, which is a real drawback if you are panning. I've seen several captures taken by all of the wonderful photographers on here using 1.4X and 2Xs. Usually with Canon L prime telephoto lenses. Personally I would not recommend one on the above mentioned lens if you are shooting with a Canon system. I'm sure you'll get several other thoughts on using teleconverters.
To prove this isn't a grump, I'll go ahead and answer your question in general terms, since it's a general question. Almost without exception it is best to follow the recommendation of your lens manufacturer and to stick with TCs made by the same lens maker for your specific lens.
Within that, there are simply some combos that work better than others. A TC on a 300 f/2.8 is likely to give better results than the same TC even if it's also recommended for a 70-300. There are quality differences between lenses, and a TC may tend to exaggerate issues with lower priced lenses.
There's also the question of TC "power." In general a 1.4x is going to give better results than a 2x, while a 1.7x might be a reasonable compromise if you really want more power than a 1.4x.
TC's also may require you to use a steadier tripod and head to help dampen vibration, which is much more problematic as lenses stretch, whether they are actually longer or you add a TC. With really long lenses plus a TC you might even have to add aftermarket braces, as I feel is necessary with my Nikon 500 f/4 and a 2x. Kirk makes a brace that extends support on the lens and TC, dramatically improving its performance.
Then there's the question of technique. As magnification goes up, issues like shutter movement, mirror movement and vibraton from your hand on the shutter release can degrade image quality. You have to develop a strategy and perhaps buy a cable release to get around them.
Is this a help? Hopefully you read past the first paragraph so I could prove that I'm not grumpy about your question!!!!!
My 100-400 L does not fare so well even though Canon says it is OK. I quit using any TC on this lens. I think Juza's comment re "sharpness to spare" is a very valid point.
I`m still happy with the purchase of the TC because I was aware of the basic drawbacks. When the light is right and the subject calls for it, I have no hesitation to use the TC, with the lens wide open, if needed. I consider it a useful accessory, not a way to turn my lens permanently into a 560/8.
IMO, if you already have a high quality prime telephoto, a 1.4x converter is a wise addition, especially, if the resulting combination is f/5.6 or faster. f/8 gets problematic but is usable. You may get away with 2x on fast sharp lenses like 300/2.8 or 400/2.8. It is advisable to use your lens manufacturer`s TC-s.
If you start with a 70-300/5.6 zoom, TC-s are a waste of money. With optically non-matching lenses, the results are going to be bad. You could get better quality by cropping and upsizing your images.
On a positive note, you may not necessarily loose AF at effective apertures tighter than 5.6.
I don't know if all Canon cameras behave the same way, and I don't have a Canon, but my camera manufacturer claims the same thing, i.e. no AF below 5.6, but my particular camera has no problem focusing with the TC at an effective aperture of f8. So my point is try it ... you might get lucky.
Good luck
Bob