I'm a wildlife photographer with an emphasis on rare birds and other species. Over the past 40 years, I've used Leica, Ricoh, Sony Alpha, Lumix and Nikon systems but decided to switch to Canon when I got more serious about wildlife photography.
I purchased one of the early 100-400 USM II for my 7D Mk II from a Canon dealer. Within the first few months I found lens would often not autofocus unless the lens was fully retracted, particularly with the 1.4x attached. In addition, many pictures were showing echo-like artifacts when there were branches, narrow leaves, long blades of grass or other linear features in the background or foreground. By "echo" I mean these kinds of narrow features would often show up doubled or tripled in the image. Some sample photos showing the problem are provided below.
Last year I sent the 100-400 and 7D-II back to Canon for evaluation. After a month or so, Canon sent the camera system back and said the echo artifacts in the photos I had sent were from chromatic aberration which was normal for this lens. I've seen chromatic aberration in other lenses, but never like this.
I then showed some of the same photos to two experienced wildlife photographers who were also using the 100-400 II, and both said they had not seen these kinds of artifacts in their images.
The artifacts are so distracting that they have ruined many otherwise nice shots. Even when there are no obvious echoes, the bokeh is often so bad that it also spoils the photo. I assume this from the same cause.
When there are no linear features in the background or foreground, the 7D-II + 100-400-II combination has provided me with some exceptional photos. Unfortunately, because I spend a lot of time photographing in forested and brushy habitats, most of my photos end up degraded by the artifacts. It's been disappointing and frustrating. Many of the subject animals were very difficult to locate and get well framed. Some of them are so rare and difficult to locate that I will never have another chance to photograph them.
I'm posting this to ask if other photographers using the 100-400-II have experienced these kinds of artifacts ... or whether I should send the lens back to Canon again for further evaluation and repair. If any of you have experienced these kinds of artifacts, did you find a way to prevent them and ensure good bokeh? My artifacts and bokeh problems seem to show up at any aperture, focal length, or shutter speed settings.
Thanks to all for sharing your thoughts. Looks like I came to the right place to ask about this. I didn't expect so many replies or such quick turn around. Much appreciated.
@ Bob: The camera and lens have never been dropped or mishandled in any way. The artifacts were showing up right after I received the lens. All but one of the sample photos (sapsucker - 1/800, f/9) were all taken without the 1.4x (which is a Canon III), but the artifacts show up with the 1.4x on as well.
@ Waddizzle: Nice photos. I can see a touch of echo in your second photo (branch along right margin) but it is minor compared to what I'm getting and doesn't spoil the shot. Your bokeh also looks smoother than mine. I've tried different shutter speeds and I haven't found a correlation with the echoes. The sample shots range from 1/250 (elegant trogon-f/5.6 and goshawk-f/6.3) to 1/1600 (rose-throated becard-f/5.6, hoping to catch it in flight). The ground doves were at 1/1000 f/5.6 and the brown thrasher was at 1/500 f/5.
I use back-button focus as well ... which helps in other ways but doesn't get rid of the artifacts. MF isn't really an option since many of my subjects move around quickly and are hard to get in focus even with AF. IS-off usually isn't an option since my hand isn't that steady and animals are most active in low-light conditions ... so with IS off I'd have to push up the shutter speed which would require unacceptably high ISO. Not sure how an IS problem would produce echoes. However, I'll do some on/off comparisons and see if it resolves the issue.
@ ebiggs1: I generally use One Shot and IS (no tripod). I haven't messed with the focus adjustment since it seems good as is. I do use a Hoya Fusion UV filter (over $100) to protect the front lens surface since I'm often bushwhacking off trail. It has an anti-reflective coating with near 100% transmissivity so I don't think it could be causing the echoes. However, I'll take some comparison shots with it on/off and see if that reveals anything.
@ diverhank: There's no way for me to avoid busy backgrounds given where most of my subjects are found. The two Canon photographers I mentioned in my original post are both dedicated bird photographers who take most of their images in the same kinds of habitats (forests, brush, shrubs, grasses, etc.) but haven't experienced the same kinds of echoes ... though both told me they have had disappointing bokehs at time. This is why I wondered whether my lens is defective.
@TTMartin. Also nice photos. The echoes in my shots are present pre-processing; if I use sharpening at all it is very little. Just to give 2 examples, other than a little exposure adjustment, the two images below have no sharpening or other processing, yet they both show 2-3 echos on branches, etc.
With the 1.4x, I don't think I've ever obtained images with the quality of your first two shots, but I'm strictly hand-held. In any event, your bokeh looks smoother than what I'm getting and I don't see any hint of echo artifacts in yours. Were those taken with a 100-400-II?
JeffD and all,
Your artifacts are interesting to me, and I try to image (without success) what could cause them. The background objects are brought to a focus in front of the sensor, and the light rays then diverge before they hit the sensor.
I have used a 60D and Canon 100-400 mm zoom for about 3 years now, and your post reminded me of a photo I took a couple of years ago. It has terrible bokeh, by chance, and was my first training of the importance of this characteristic. I dug it out, and am including it. It has the type of background that would bring out your artifacts: large grasses. But the out-of-focus grasses do not have that multiple-edge look yours have.
My setup: 60D, Canon 100-400 mm original lens, Hoya UV filter for lens protection
I think that this would be a good question for a Canon engineer. These lenses are complicated affairs, and someone who has experience in their design and testing might be required to get to the bottom of your issue. If it were my lens, I think that I would push Canon pretty hard to either fix or replace my lens. Aftre all, their reputation depends on it.
Edward1064
