100-400 L with a 1.4 TC

Is anyone using this combination? Do you like it? In addition to the autofocus issues (needs to have f/8 to autofocus), I am finding the shots straight out of the 5DIII to be close to or better than those taken with the 1.4 TC. I am wondering if the 1.4 TC doesn't degrade the IQ much of better glass (70-200 IS II, big whites, etc), but does in the 100-400 L.

A few examples of approximately 100% crops (yes, I am pixel peeping). All shots taken from tripod, remote release, manual focused using live view. Took multiple shots and below represents the "best":
A printout of the ISO 12233 chart you can download form cornell university..both images tweaked in LR to increase sharpness, etc taken ~35 ft (10 m):
5DIII only:
http://farm9.staticflickr.com/8089/8...5647df08e6.jpg
5dIII LR4 600x400-0073 by kayaker72, on Flickr

5DIII with 1.4 TC:
http://farm9.staticflickr.com/8234/8...ab34cefd66.jpg
5dIII 14x LR4 600x400-0069 by kayaker72, on Flickr

Closer tree (~100 ft or 30 m):
5DIII only:
http://farm9.staticflickr.com/8515/8...26f1eab2f6.jpg
5DIII 600 400-0092 by kayaker72, on Flickr

5DIII with 1.4 TC:
http://farm9.staticflickr.com/8386/8...117406051a.jpg
5DIII 14tc 600 400-0094 by kayaker72, on Flickr

Tree Further away (~150 ft or 45 m):
http://farm9.staticflickr.com/8505/8...9704d5f67f.jpg
5DIII 600 400-0097 by kayaker72, on Flickr

http://farm9.staticflickr.com/8383/8...e37c843253.jpg
5DIII 14tc 600 400-0096 by kayaker72, on Flickr

Thanks,
Brant

I've used the combo, performance is acceptable but I haven't done any detailed testing as you've done, Brant. Might need to do some of that with an ISO 12233 chart. OTOH, I often need to crop a bit (with 560mm...and as you know, sometimes even with 1200mm). Below is a 'real world' shot with the 100-400L + 1.4xIII. The 'final' image ended up being 6 MP after cropping (~3000x2000 pixels), and without the 1.4x on there, the same image would have ended up as a 3 MP image. Below are processed image and a 100% crop of it. It was shot at 1/320 s, f/8 and ISO 5000 on the 1D X.

Attachment 1723

Attachment 1722

Quote:

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Originally Posted by Kayaker72

Is anyone using this combination? Do you like it? In addition to the autofocus issues (needs to have f/8 to autofocus), I am finding the shots straight out of the 5DIII to be close to or better than those taken with the 1.4 TC. I am wondering if the 1.4 TC doesn't degrade the IQ much of better glass (70-200 IS II, big whites, etc), but does in the 100-400 L.

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It degrades them all, but the big whites just start out so much better than the 100-400L that you wouldn't notice it as much.
http://www.the-digital-picture.com/R...mp=7&APIComp=0

I was not happy with the 100-400mm plus convertors. Smaller prints it would probably be ok.

Quote:

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Originally Posted by HDNitehawk

It degrades them all, but the big whites just start out so much better than the 100-400L that you wouldn't notice it as much.
http://www.the-digital-picture.com/R...mp=7&APIComp=0

I was not happy with the 100-400mm plus convertors. Smaller prints it would probably be ok.

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This is essentially what I am wondering. My likely flawed but hopefully holding some merit analogy is based on the transmittance on the MTF charts. I don't know what optically causes lower transmittance, but some optical inperfection(s) in each lens. Comparing f/8 the big whites/70-200 f/2.8 IS II have ~0-2% optical flaws (lack of transmittance) at f/8. If the 1.4 TC doubles that to 1-4% "flaws", it still isn't a big deal as the MTF score/transmittance is still >96% (with the "Excellent" standard being 90%). But if the 100-400L has ~6% optical flaws at f/8 and the 1.4 TC doubles that, well, 88% transmittance is starting to be a big deal, as it drops you below the "excellent" standard of 90% or 0.9.

I'll play around with my post-processing a little more. I think JRW is right in that there is an exposure issue and combining what John and JRW said, if there is more data in a cropped image with the TC, it may post-process better.

So if I catch the logic here is that on the big white lenses the teleconvertor degrades the image by a certain amount, say double from 2% to 4%. Since the 100-400mm starts much worse say 4% degradation it ends up doubling to 8%. Those numbers do not relate to anything and are just an example.

I used teleconvertors on the 100-400mm and 5D II when I had the lens. I never got a product that I would do a large (over 8x10) print with.
It sounds to me like you are going to be thinking about one of those big white lenses shortly.

As for my tests, 1 of 3 images with the 1.4 TC did sharpen up to be clearly better than the shot with the 5DIII alone with additional post processing in LR4. I didn't try JRWs suggestion, as I've never done anything like that so it will take me some time. I'd call the other two shots after additional sharpening/contrast/etc about even or an edge to the 5DIII alone. Overall, this has me thinking that I need to conduct more tests with AF, which I can't do until Canon releases the firmware update for the 5DIII, which they've "promised" in April.

Quote:

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Originally Posted by HDNitehawk

It sounds to me like you are going to be thinking about one of those big white lenses shortly.

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Quote:

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Originally Posted by jrw

Scary thought but this is almost exactly the path that led to selling the 100-400 and getting the 300 f2.8 after close to a year with a used 300 f4, also sold, while I tested the theory out before spending the big bucks. No regrets image wise, just a little heavier to carry around.

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I could be considering that path......;):cool: But it isn't in the cards for at least a year or two. So, it also depends on what comes out between now and then. For example, a 100-400 II or a 400 f/5.6 IS that worked well with the 1.4 TC could be enough. But for now, my core kit of 5DIII, 7D, 24-105 L, 50 f/1.4, 100 f/2.8 L, and 100-400 L should be good.

I've been toying with the idea of a 400mm f5.6 just to get the sharpness along with the additional reach. I usually end up with some cropping and I find I need to start with as sharp as image as I can possibly get in order to end up with a cropped image I'm happy to keep. Either that or I need to get friendlier with the birds.:D

Thanks....I'll give it a try....