I had to go visit the dentist this week, and I had just enough time free before the appointment that I could sneak down to the Palo Alto Duck Pond with my gear and do some head to head tests and start learning how the new lenses are going to operate.
This exercise was intended to try to understand a couple of things: first, how well the image quality of the T3i stands up to the 7D, so I know what situations I have to depend on the 7D, and when I can use the 2nd body. Second, I want to get some sharpness tests of the 70-200F2.8l+2.x combo against the 300F4+1.4x to see whether the former would work as my birding rig, and if not, how far can I push it before image quality starts to fail. And third, I’ve just had this nagging question about whether the 7D needs to be serviced and whether it’s giving me the clean, sharp images I expect from it.
To try to start figuring this out, I sat next to the pond (trying to avoid the kids with the bag of bread and the resulting chaos, not always successfully) and shoot the same subjects at the same time using the same settings so I have some rational images to do comparisons with. For all of these images, both bodies were set to ISO 400, AF to the center sensor, Aperture mode (adjusted by +2/3 stop as I typically do), with AF set to AI Servo and autoexposure to Center Weighted Average; I had no custom settings set.
These images are shot raw, with almost no processing; perhaps a bit of exposure and contrast tweaking, but all have the same default sharpening and no noise reduction or lens correction. The camera profile was set to camera neutral. All lenses were shot hand held, with IS on, set to setting 2.
Also, just to be clear, here’s the list of lenses and bodies I’m experimenting with. You have to be really careful because after a while, all of the letters can start running together, and it matters whether it’s the “70-200F2.8L IS” or the “70-200F2.8L IS II”. The “2.X II” teleconverter isn’t as sharp as the newer “2.X III”, but if you aren’t paying close attention, you can miss the difference in the model naming.
- 7d body
- T3i body
- 70-200F2.8L IS (not “IS II”)
- 2.x Teleconverter II
- 1.4X Teleconverter II
- 300 F4 IS
Click through each image to see the large version:
- The 7D, with 70-200X2x at 400mm, F8
- The t3i, with 70-200X2x at 400mm, F8
- here it is at 300MM, F8
- 300F4+1.4x at F5.6
Here’s a second round, shooting at something close up instead of relatively far away:
- 7D, 315MM @ F5.6
- 7D, 300F4+1.4x @ F5.6
- 7D, 280mm – 70-200+1.4x @ F5.6
- 7D, 280mm – 70-200+1.4x @ F5.6
- T3i, 300mm – 70-200+2x @ F5.6
- xT3i, 400mm – 70-200+2x @ F8
- xT3i, 300mm+1.4x @ F5.6
So my verdict?
If you look at those last two images side by side, you can see an obvious difference:
The right image is significantly sharper. That’s the 300F4+1.4x combo. The 70-200+2X seems to be acceptably sharp up to about 300mm, and then softens. In some cases, especially with relatively close birds, it might be “good enough” if the other lens isn’t available, but honestly, I think that’s wishful thinking. It’s just too soft. The quick testing I did with the 70-200 with the 1.4x seems to be nicely sharp, but even that the sharpness falls off as it heads towards max magnification.
This is normal with teleconverters. It’s not a matter of whether the image will degrade, but whether that degradation is acceptable. The 2x will soften your image; don’t pretend your 300+1.4x is going to be as good as a 400F4 — this is understanding the tradeoffs between quality, budget and having to hire a sherpa with a mule to carry it all.
So, my bottom line?
I’m not seeing any significant change in image quality between the 7d and the T3i. This is good; I didn’t expect to, since they use the same sensor down in the bowels; the pricing difference between the two bodies is primarily about manufacturing and features — and when you pick the two up in each hand, you can definitely tell the difference. The 7d feels built like a rock, the T3i feels more “plasticky” and is definitely lighter. It seems perfect for my needs as a 2nd body, though, and a good value compared to the 7D. (this also implies there’s no obvious issues with the 7D body indicating it needs a trip to the shop. also good). This means I can feel comfortable using both bodies, within the limits of the T3i — for instance, the more limited buffer for burst shooting.
The 70-200+2x combo is noticeably softer at 400mm than the 300+1.4x is; for my purposes, it’s “too soft”. This doesn’t surprise me much. I was hoping I could use it as my primary birding gear, but I wasn’t depending on it. I now know to stick with the 300 setup for that. From what I can tell, the 70-200+2x is acceptably sharp up to about 300mm, so in a pinch, I can use it if the 300mm is handy with some limitations, but the 70-200+1.4x is even sharper in that range, so I should use that instead.
Shooting at F8 helps, as you might expect, when compared to wide open. But doesn’t make enough of a change to change the results.
(and because I want to be clear on this: this isn’t a ‘problem’ with the lens. I was experimenting to see if I could push the envelope in an attempt to lighten the kit I haul around. I thought it was unlikely I’d get away with this without spending a lot more money on the 70-200F2.8 IS II lens, which is just beyond my budget. My opinion, honestly, was that I’d rather buy these lenses now and save up for my 500mm than put even more money into the more expensive 70-200. That’s all part of looking at the bigger and long-term picture of what your needs and priorities are….
The attempt was worth a shot, and now I know. Doing these kinds of tests is an aspect of learning your gear, so you know without thinking (or worrying!) what to grab to make a shot happen. If you know what the gear can do — and what it can’t — you can focus more on the shot, and less on wondering if you’re going to get it.
Do you know how your lens will react if you change it from F5.6 to F11? What center-weighted exposure mode does vs. evaluative, and when to use which?
you really should, because if you stop to think through which settings to use when, by the time you think it through, the shot will be gone. Putting time into experiments like this is part of the process of making the gear more invisible to the moment.