2x Extender

Shark · May 2, 2016

Is there a 2X extender out there that is autofocus, that will extend my Canon EF 100-400mm f/4.5-5.6L IS USM Telephoto Zoom Lens. It is the lens that telescopes out to 400mm. And are they really that good for wildlife shots.

Thanks, Shark

kdog · May 2, 2016

The 100-400 will never autofocus with a TC-2x regardless of the brand. It's a matter of arithmetic.

Most or all newer Canon bodies focus at a minimum aperture of f/8. (I'm not sure about the Rebel line which may need f/5.6 for AF.) You don't say which body you're using, so we'll assume the best case that you have an f/8 focusing body. A TC-1.4x subtracts one stop of light, and a TC-2x subtracts two stops. So your 100-400/TC-2x combo yields f/11 which is a smaller effective aperture than the f/8 minimum for AF. So if AF is important to you then swap your TC-2x for a 1.4x and that will work.

You do lose some sharpness with TCs. How much you lose depends on your other gear and your technique. It's up to you to discover for yourself whether it's worth the tradeoff for the added magnification.

PS: For completeness, I would add that there's a hack you can do to get around the f/8 limitation with your combo. You can tape over an electrical contact on the TC so it's "non-reporting". Then your body will be fooled into thinking there's no TC and will attempt to AF. It rarely works well (else Canon wouldn't have that limitation.) But in bright light you may be able to occasionally lock focus that way. You can find details of the tape hack on Google.

pathfinder · May 2, 2016

Even without a TC, a 100-400 at f5.6 at the long end will begin to have trouble with autofocus when the light gets low enough - like after sunset, or back in the deep shade in a forest on a cloudy day. At least mine does on a Canon 1DX body...

Fast, accurate autofocus requires light, and even f4 lenses autofocus slows down a bit after sunset. I don't know the lighting conditions the OP plans to shoot in, I just know that wildlife is not infrequently captured before sunrise, or after sunset.

You will be able to focus manually of course with a TC, but the image will be really dark at f11. Use the depth of field preview button on your camera body to stop your lens down to f11 while you view through the lens finder to get an idea what I am describing. You will probably have to wait 10-30 seconds for your eye to adjust to the darkness of the image.

jhefti · May 3, 2016

I've never used a 2x, but even a 1.4x that I use every now and then significantly degrades the image. They're always just a little soft, even on the best f/2.8 telephotos and high end bodies. I almost always regret using them. I even tried the Canon 200-400mm f/4.0, which I borrowed from CPS at an event, and found the 1.4x internal extender to be less than satisfying.

I don't do much wildlife photography, but I might suggest you look for a less expensive (i.e., not a Canon) 600mm lens. I'm sure there is a decent one out there, but I'm also sure it's still a lot more expensive than a 2x extender. Still, I think you'll be really disappointed in the 2x on a 100-400.

ADDENDUM: I just checked eBay and really didn't find a 600mm in any price range that could reasonably compete with a 2x TC. There are the Tamron and Sigma 150-600mm lenses that are inexpensive, but I have no clue as to how they compare with your potential combination. A used Canon 600mm f/4.0 runs about $3K. I was also curious, as I'm doing a trip to Africa and will be doing some wildlife photography.

kdog · May 4, 2016

jhefti wrote: »

A used Canon 600mm f/4.0 runs about $3K.

The very old pre-IS versions go for around $3K. The old 600 f/4 IS (Mark I, not Mark II) goes for twice that on the used market. The MKII is almost $12K.

Shark · May 4, 2016

Thanks for the answers everybody. I kind of had a feeling the answers were going to be like that.

jhefti · May 4, 2016

kdog wrote: »

The very old pre-IS versions go for around $3K. The old 600 f/4 IS (Mark I, not Mark II) goes for twice that on the used market. The MKII is almost $12K.

Yeah, that's pretty much what I found.

I really have no use for a 600mm lens, aside from the occasional trip to places that require the reach to get wildlife. I spoke to several photographers who regularly shoot wildlife in Africa, and most don't think a 600mm is necessary. I'll probably pass on this and just use my 400/2.8, though it's heavy and awkward to carry around.

kdog · May 5, 2016

jhefti wrote: »

Yeah, that's pretty much what I found.

I really have no use for a 600mm lens, aside from the occasional trip to places that require the reach to get wildlife. I spoke to several photographers who regularly shoot wildlife in Africa, and most don't think a 600mm is necessary. I'll probably pass on this and just use my 400/2.8, though it's heavy and awkward to carry around.

Depends on where you go in Africa; it's a pretty big continent. If you're shooting in the jungle where you don't see an animal until you're on top of it, or shooting lions lying in the roads like at some of the fenced in game parks, then no. But if you see a cheetah on the back side of a watering hole in the desert, then you're going to be frustrated as hell if you don't have a long lens. I packed both my 100-400 and 500mm f/4 last year on a month long trek through Botswana and Namibia and I was really glad I did. I probably used both lenses equally. Pics here if you want to take a look. http://www.desertilluminations.com/Vacation/Africa/
About 2/3rds of the way through the gallery is Etosha in Namibia which is more desert climate with more open spaces. There I used the 500 almost exclusively as you can tell from the EXIF info.

I also often use my TC-1.4X with the 500 and usually get pretty good results -- better than cropping extensively in post. I've found that thermal distortion from heat waves cause more degradation than the amount you get from a TC. Shooting critters at long distances can be tough no matter what equipment you have.

I certainly wouldn't mess with a 600mm if I had a 400 f/2.8. I hear they take TC's very well. Add a TC1.4x to that and you have your 600mm f/4, or even an 800 f/5.6 with a 2x. Lots more flexibility with that setup! Sure, if you pixel peep in ideal conditions, you're going to see that the TC degrades your shots a little. But in the real world, I don't think it really matters all that much. Better to be flexible and get the shot.

The 400 f/2.8 is pretty much the same size and weight as the 600. But the 2.8 would be a real win for shooting in the twilight hours, especially for focusing.

jhefti · May 5, 2016

kdog wrote: »

The very old pre-IS versions go for around $3K. The old 600 f/4 IS (Mark I, not Mark II) goes for twice that on the used market. The MKII is almost $12K.

kdog wrote: »

Depends on where you go in Africa; it's a pretty big continent. If you're shooting in the jungle where you don't see an animal until you're on top of it, or shooting lions lying in the roads like at some of the fenced in game parks, then no. But if you see a cheetah on the back side of a watering hole in the desert, then you're going to be frustrated as hell if you don't have a long lens. I packed both my 100-400 and 500mm f/4 last year on a month long trek through Botswana and Namibia and I was really glad I did. I probably used both lenses equally. Pics here if you want to take a look. http://www.desertilluminations.com/Vacation/Africa/
About 2/3rds of the way through the gallery is Etosha in Namibia which is more desert climate with more open spaces. There I used the 500 almost exclusively as you can tell from the EXIF info.

I also often use my TC-1.4X with the 500 and usually get pretty good results -- better than cropping extensively in post. I've found that thermal distortion from heat waves cause more degradation than the amount you get from a TC. Shooting critters at long distances can be tough no matter what equipment you have.

I certainly wouldn't mess with a 600mm if I had a 400 f/2.8. I hear they take TC's very well. Add a TC1.4x to that and you have your 600mm f/4, or even an 800 f/5.6 with a 2x. Lots more flexibility with that setup! Sure, if you pixel peep in ideal conditions, you're going to see that the TC degrades your shots a little. But in the real world, I don't think it really matters all that much. Better to be flexible and get the shot.

The 400 f/2.8 is pretty much the same size and weight as the 600. But the 2.8 would be a real win for shooting in the twilight hours, especially for focusing.

Thanks Kdog--most helpful! A 400/2.8 is a nice lens, and it does take a TC reasonably well. I think it's just hard because I'm used to the native IQ and the TC does noticeably degrade it. Still, I'm sure I'd get some decent shots with it.

Thanks for the suggestions!

And BTW, we'll be in Tanzania and Kenya, doing some medical work and climbing Kilimanjaro as well as spending time in the Serengeti. It's still a work in progress at this point, though.

John

kdog · May 5, 2016

jhefti wrote: »

Thanks Kdog--most helpful! A 400/2.8 is a nice lens, and it does take a TC reasonably well. I think it's just hard because I'm used to the native IQ and the TC does noticeably degrade it. Still, I'm sure I'd get some decent shots with it.

Thanks for the suggestions!

Glad I could help!

And BTW, we'll be in Tanzania and Kenya, doing some medical work and climbing Kilimanjaro as well as spending time in the Serengeti. It's still a work in progress at this point, though.

Oh!! Let's talk! That exactly the trip I have planned for next June (2017). I hadn't planned on Kilimanjaro, but now you've got me thinking.

pathfinder · May 5, 2016

kdog wrote: »

Depends on where you go in Africa; it's a pretty big continent. If you're shooting in the jungle where you don't see an animal until you're on top of it, or shooting lions lying in the roads like at some of the fenced in game parks, then no. But if you see a cheetah on the back side of a watering hole in the desert, then you're going to be frustrated as hell if you don't have a long lens. I packed both my 100-400 and 500mm f/4 last year on a month long trek through Botswana and Namibia and I was really glad I did. I probably used both lenses equally. Pics here if you want to take a look. http://www.desertilluminations.com/Vacation/Africa/
About 2/3rds of the way through the gallery is Etosha in Namibia which is more desert climate with more open spaces. There I used the 500 almost exclusively as you can tell from the EXIF info.

I also often use my TC-1.4X with the 500 and usually get pretty good results -- better than cropping extensively in post. I've found that thermal distortion from heat waves cause more degradation than the amount you get from a TC. Shooting critters at long distances can be tough no matter what equipment you have.

I certainly wouldn't mess with a 600mm if I had a 400 f/2.8. I hear they take TC's very well. Add a TC1.4x to that and you have your 600mm f/4, or even an 800 f/5.6 with a 2x. Lots more flexibility with that setup! Sure, if you pixel peep in ideal conditions, you're going to see that the TC degrades your shots a little. But in the real world, I don't think it really matters all that much. Better to be flexible and get the shot.

The 400 f/2.8 is pretty much the same size and weight as the 600. But the 2.8 would be a real win for shooting in the twilight hours, especially for focusing.

I see that issue a lot with lenses longer than 400mm -- even over snow fields in Lamar Valley in Yellowstone on winter days when the sun comes out. Usually when shooting things reasonably close to the ground, or snow, that has been warmed by the sun. Even if the ambient temperature is in the single digits - Fahrenheit single digits.

I never really expected to see heat shimmers over snow fields, but it does occur, and heat waves are far more disturbing to the image, than using a 1.4 TC.

The first time I saw it over snow fields photographing wolves in the distance, it took me a few seconds to realize what was happening. You see it fairly often in Africa over the 4 -6 hours around noon, but that is expected.

jhefti · May 6, 2016

Kdog--happy to talk! We're in the early stages of putting this together, and it certainly won't happen until sometime in 2017 at the earliest.

Regarding IQ degradation due to heat, I see this all the time on artificial pitches. Some soccer games are so bad that I have nothing usable beyond the near third of the pitch. The first time it happened--years ago, when I was new to photography--I thought there was something wrong with my lens or camera. Fortunately more experienced people told me the real issue.

That said, distortion and degradation are additive, so putting on a TC will only make the problem worse. I shot a day game at Levi's Stadium last year and tried using a 1.4x TC on a 400/2.8. Even though it's a grass pitch, the images from centerfield on were worthless, at least for any media uses. I took off the TC and things improved a little, though I was still not able to get clean images of the far third of the pitch.

jhefti · May 6, 2016

pathfinder wrote: »

I see that issue a lot with lenses longer than 400mm -- even over snow fields in Lamar Valley in Yellowstone on winter days when the sun comes out. Usually when shooting things reasonably close to the ground, or snow, that has been warmed by the sun. Even if the ambient temperature is in the single digits - Fahrenheit single digits.

I never really expected to see heat shimmers over snow fields, but it does occur, and heat waves are far more disturbing to the image, than using a 1.4 TC.

The first time I saw it over snow fields photographing wolves in the distance, it took me a few seconds to realize what was happening. You see it fairly often in Africa over the 4 -6 hours around noon, but that is expected.

Actually, it's not heat per se that causes the problem, but thermal gradients. The index of refraction is temperature dependent, so any time there are significant differences in temperature between the ground and the nearby air you'll get the effect. It's just that the most familiar examples are between hot ground or pavement and the nearby air.

Still, would love to try to get the shots you were trying to get! Haven't done a whole lot of wildlife photography, even though I do a lot of outdoor sports. Sure must be fun!

pathfinder · May 6, 2016

jhefti wrote: »

Actually, it's not heat per se that causes the problem, but thermal gradients. The index of refraction is temperature dependent, so any time there are significant differences in temperature between the ground and the nearby air you'll get the effect. It's just that the most familiar examples are between hot ground or pavement and the nearby air.

Still, would love to try to get the shots you were trying to get! Haven't done a whole lot of wildlife photography, even though I do a lot of outdoor sports. Sure must be fun!

Agreed, I just was surprised to see that effect over snow fields in Yellowstone. Thermal gradients, as you said.

I think the air gets warmed and actually rises too.

But the altered refractive indexes are the real issue, as you described their temperature dependence.

jhefti · May 18, 2016

pathfinder wrote: »

Agreed, I just was surprised to see that effect over snow fields in Yellowstone. Thermal gradients, as you said.

I think the air gets warmed and actually rises too.

But the altered refractive indexes are the real issue, as you described their temperature dependence.

Yeah, I'd be surprised to see it over snow too. Then again, I was surprised the first time it happened to me, on an artificial soccer pitch during a blistering hot afternoon. It took me a while to realise what was going on.

2x Extender

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