5D+70-200/2.8mkII+2xTC or 5DII+1.4x and crop? (1 Viewer)

I currently own a 5D mkI (12.8 MP) and a 70-200/4IS. I don't shoot wildlife a lot, but when I do, it's while travelling the world and 200mm on FF is not enough. I think that for my shooting 400mm is OK.

While travelling: this is in my bag:
One or two FF bodies, 16-35II, 24-105, 70-200, 580EXII.

I've been thinking about various options:
- 400/5.6: yes very impressive IQ, but too bulky for travel, no IS and no zoom
- 100-400: so so IQ, not fast, won't give up my 70-200 for it.
- 70-200/2.8mkII w/ TC's: I would trade my 70-200/4IS for this lens and I can give it a lot of good use it at home (weddings, family portraits, events, stage, etc.)

I rented the 70-200/2.8ISmkII recently to shoot a wedding and I tested a Canon 2xExtenderIII (the new one) on it. I was a bit disappointed. Yes it is quite sharp, but there was not much contrast left and weird OOF areas in the immediate background.

So I was thinking, hopefully you can follow and comment:
1. For wildlife images, 10-12 MP is enough for me
2. I will get a 70-200/2.8ISmkII probably anyway and sell my 70-200/4IS
3. I will most likely get a 5DmkII anyway (for other reasons) to become my main body and keep the 5D as 2nd camera for weddings and stuff
4. A 1.4xTC makes IQ suffer much less than a 2xTC
So: why don't I get the 5dmkII and the 70-200/2.8mkII and get a very good 1.4xTC to get to 280mm. Then, in PP, I crop the 21MP image to 10-12 MP, allowing for another 1.4x "magnification". No interpolation involved, just quality optics and pixels.
From reasoning, I expect the final IQ to be better than that from a 2xTC (even a new III version) on my 5DmkI, using all the pixels. Though I know theory and practise can be miles apart.

Edit1: after rereading, just to make everything perfectly clear, here is what I want to compare:

5D (mkI) + 70-200/2.8ISmkII + 2xExtenderIII (12.8 MP)
vs.
5DmkII + 70-200/2.8ISmkII + 1.4xExtender + crop to 10-12 MP

Edit2: I would like to add that I am determined to stay on FF. I see a lot of folks on this forum shooting APS-C and that makes a lot of sense if birding is your main thing. For me, it is more general photography and I found that FF bodies fit my needs best. I probably wouldn't buy a APS-C just for shooting birds. That said, if anyone thinks a 40D+1.4x+70-200/2.8ISmkII beats a cropped 5DmkII, I would really like to know about it. Used 40D's don't cost that much nowadays...

Hope you will comment.

Spike

Overall image quality between the 100-400mm and the 70-200mm f2.8 IS L M2+2*TC is pretty much identical - with both lenses showing similar effects (on occasion) with the background blur as well as not being their sharpest wide open (stopping down to f7.1 makes a noticeable improvement).
You can see some examples here: http://photography-on-the.net/forum/showthread.php?t=869226
Overall the 100-400mm retains the edge but only very marginally and outside of side by side test shots I doubt you could tell the difference (esp after editing).


As for the idea of cropping whilst shooting with a 1.4TC I've never done a comparison (no 5DM2 to do it) but from all that I've read cropping to gain magnification over using a teleconverter nearly always results in a lesser result as compared to using the teleconverter. Of course this is partly based on your output needs and for some their output (eg the net) means that the quality comparison is harder/impossible to see in some cases.

Overall either combo will work, but I'd fully expect the 2*TC to give you more to work with. Personally I'd say that you need to determine how strong your birding interest is - if its really strong then go for the 2*TC over the 1.4 first and then pick the 1.4 up later - if its lesser than do the reverse and (until you get the 2*TC) use cropping for the current time.

Overread said:

Overall image quality between the 100-400mm and the 70-200mm f2.8 IS L M2+2*TC is pretty much identical - with both lenses showing similar effects (on occasion) with the background blur as well as not being their sharpest wide open (stopping down to f7.1 makes a noticeable improvement).
You can see some examples here: http://photography-on-the.net/forum/showthread.php?t=869226

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Hi, thanks for reading and your reply! Read the entire thread you gave me. Noticed you're in it too . Yes I see the 100-400 holds its own compared to the 70-200mkII with 2x, but I would never even consider carrying 2 monsters while travelling and I'm getting the 70-200mkII anyway for its native FL range. Birds or other wildlife is just occasional for me.

As for the idea of cropping whilst shooting with a 1.4TC I've never done a comparison (no 5DM2 to do it) but from all that I've read cropping to gain magnification over using a teleconverter nearly always results in a lesser result as compared to using the teleconverter.

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Quite! Of course you are right. This is true as long as you stick to one camera. In my suggestion, I compare a 21mp with crop to a 12 mp without crop. I think this scenario might work for the 5DmkII and crop. And don't worry I noticed you understood by reading your answer. It's just that I don't own a 5DmkII yet, so I can't test it myself.

Personally I'd say that you need to determine how strong your birding interest is - if its really strong then go for the 2*TC over the 1.4 first and then pick the 1.4 up later - if its lesser than do the reverse and (until you get the 2*TC) use cropping for the current time.

Click to expand...

Now we're getting there! It's lesser, so my incling is to start off with the 1.4x and just see if I ever really need substantial extra reach. I can't imagine that I will really need much more reach while travelling. I know that i won't ever leave the 2.8 at home for travel, and I'm pretty sure my travel tele needs won't make me carry much more weight. And if at some point they do, I might consider using a 7D+1.4x instead of a 2xTC on a 5DII.

Anyone have a 5DII here to test my setup? Guess not, being in a birder forum..... But who knows....

Thanks!