Analysis of EOS 7D AF performance-my final verdict

[arash_hazeghi]

After the original thread and the follow up on the performance of EOS 7D new AF system I received a number of emails from BPN friends to update the article with the new 7D that I purchased (the original was returned). I was somewhat reluctant to do this but I thought it might be helpful for some people. I put together a short summary of my findings with images here on my website.

[John Blumenkamp]

Arash... I appreciate your time and effort in posting the follow-up review.

My take on the 7D is in-line with your comments. In short, it is a fine camera and a step-up from the previous XXD bodies in terms of build, features and overall operation. But for top IQ and AF performance, especially for the subject matter we all enjoy photographing here at BPN, it is clear the 1D series is the best Canon has to offer, as well it should be considering the price difference.

I think the general sentiment of 'fine but not stellar' performance is a result of what you alluded to in your review... 'on paper' the 7D is a birders dream, and expectations were certainly high. Actual performance is of course the final verdict.

Thanks again.

[IanWorthington]

Many thanks Arash. Your efforts are *much* appreciated.

i

[Joerg Rockenberger]

Hi Arash,

Thanks for doing such extensive testing and sharing your impression. Hope you don't get too much heat for it...

As for your results, they seem to be similar to my experience with the 7D (can be problematic against background of similar color) although I've never had the opportunity to do a side-by-side comparison with another camera body unlike you. I think the harrier image taken with the Nikon D700 is particularly telling in this regard assuming that the bird takes up a similar fraction of the VF/AF sensor than in the Canon images which clearly fail to AF.

By the way, did you notice any meaningful difference between the two 7D bodies?

Then regarding your note going to HMB yesterday: I've had planned to go there too but one look at Traffic on Google Maps convinced me not to. It's a major pain in the *&& going to HMB via 92 this time of the year. What I try to do is go photographing in the morning in Santa Cruz and then come up Highway 1 in the early afternoon. Works like a charm.

We should try to connect one of these days. JR

[Jeff Donald]

Hi Arash, very well done article and the accompanying photos are excellent at illustrating your points. I think I may have found a typo, however. In your Custom Function section, C.Fn III-4 Lens Drive when AF impossible : 0-OFF (to prevent focus hunt), is in error, I think. On my 7D, 0 is ON, not OFF.

I have two questions, maybe you can help me with. The first is your choice of Manual AF Point selection. I've been using AF Point Expansion, which the Canon White Paper you reference in your article, recommends for BIF. Do you feel this could have contributed to your dissatisfaction with the AF accuracy you encountered with your BIF shots?

The second question is your choice of Servo Tracking Sensitivity being set to Slow. I've experimented with using a higher setting and think the Tracking is improved over the Slow setting. My testing is not near as extensive as yours, but I wonder if you experimented with other settings in the course of your review of the 7D?

[Aravind Krishnaswamy]

Thanks for the great writeup Arash. I see no reason why anyone should give you any heat for sharing your thoughts after actually using 2 bodies.

[arash_hazeghi]

Hi Arash,

Thanks for doing such extensive testing and sharing your impression. Hope you don't get too much heat for it...

As for your results, they seem to be similar to my experience with the 7D (can be problematic against background of similar color) although I've never had the opportunity to do a side-by-side comparison with another camera body unlike you. I think the harrier image taken with the Nikon D700 is particularly telling in this regard assuming that the bird takes up a similar fraction of the VF/AF sensor than in the Canon images which clearly fail to AF.

By the way, did you notice any meaningful difference between the two 7D bodies?

Then regarding your note going to HMB yesterday: I've had planned to go there too but one look at Traffic on Google Maps convinced me not to. It's a major pain in the *&& going to HMB via 92 this time of the year. What I try to do is go photographing in the morning in Santa Cruz and then come up Highway 1 in the early afternoon. Works like a charm.

We should try to connect one of these days. JR

Hi Joerg,
You made the right choice by staying at home, I thought the weekend after pumpkin festival and before Halloween would be OK but I was wrong! I also spotted a short-eared hunting right before sunset, wish I had a 600!

I don' think there was a measurable difference between the two bodies that I got.

Shoot me an email if you'd like to go shooting.

[arash_hazeghi]

Hi Arash, very well done article and the accompanying photos are excellent at illustrating your points. I think I may have found a typo, however. In your Custom Function section, C.Fn III-4 Lens Drive when AF impossible : 0-OFF (to prevent focus hunt), is in error, I think. On my 7D, 0 is ON, not OFF.

I have two questions, maybe you can help me with. The first is your choice of Manual AF Point selection. I've been using AF Point Expansion, which the Canon White Paper you reference in your article, recommends for BIF. Do you feel this could have contributed to your dissatisfaction with the AF accuracy you encountered with your BIF shots?

The second question is your choice of Servo Tracking Sensitivity being set to Slow. I've experimented with using a higher setting and think the Tracking is improved over the Slow setting. My testing is not near as extensive as yours, but I wonder if you experimented with other settings in the course of your review of the 7D?

Hi Jeff,
You are right, sorry for the typo, I just checked my camera and it is set to 1, I will correct this.

I did try the expansion mode during the first shoot, while it performs good against sky it increases the tendency to lock on the BG in other situations, this was somewhat obvious in the finder when trying the 4-point expansion mode, I could see the focus shift to BG and stay there. The other problem with 4-point expansion is that at times, the camera will pick on of the 4 points randomly even when there is enough contrast under the center point this can shift the focus point a bit, My understanding is this mode is best when tracking a bird that flies parallel to the camera against sky. In order to have full control over the focus I decided to go with manual point only. Also as conditions change in the field rapidly it is sometimes difficult to switch between expansion and single point for stationery shots, the manual point is the best way to be prepared for all situations.

I also tried setting sensitivity to normal and high, actually yesterday I initially had it set to high, in my experience it increased the jumpiness of the AF a little bit so I switched back to slow.

Best,

Arash

[Jeff Donald]

Thanks again, I appreciate your input.

[Flavio Rose]

Thanks very much. I hesitate to ask such a dangerous question, but does the AI Servo represent an improvement over the 40D or 50D? If so, in what way?

[Andrew McCullough]

Thanks for doing this. It is an interesting read.

[arash_hazeghi]

Thanks very much. I hesitate to ask such a dangerous question, but does the AI Servo represent an improvement over the 40D or 50D? If so, in what way?

For static shots the new spot mode puts 7D at an advantage.

For tracking birds against plain sky 7D is good but so are 40D and 50D, all of these cameras can pick the bird easily so it's hard to improve on something that's already good. 7D does provide a slight advantage thanks to its 8fps and higher IQ over the 50.

In other and more challenging situations mentioned in the summary, 40/50D would also struggle to some extend but from my experience the AF was more stable/consistent when the center point was kept on the bird during tracking.

Here is a tern shot with 40D

[Bill McCrystyn]

Thanks Arash, you most definitely answered my question and perhaps Alex's. Thanks for the objective viewpoint - how refreshing.

[Ed Cordes]

Arash, thank you for this detailed report. From your description and examples it is evident that BIF against a busy BG is certainly a challenge for the 7D. My only input is the fact that the comparison is between the 7D at $1,700 and the Canon 1 DMK3 ($2,000+ more when newly released) and Nikon D700 ($1,000 more). So, while I agree that your conclusions represent actual performance differences it is in a way not quite a completely fair comparison. On the other hand your comparison to the Canon 40D and 50D seem more relevant as they are the same class of camera.

Please receive my comments in the light of constructive input.

[Bill McCrystyn]

And Ed, if I dare say, in the same class as the Nikon D300.

[Paul Granone]

Arash,

Anyone who expects a non-professional camera to perform like a professional camera costing many times more is not being realistic. The 7D costs $1699 and the 1D Mark III new was $4500, the D700 $2700, and the D3 $5000, and the 1D mark IV $5000. So your expectations are unlrealistic in your comparisons.

Show me a camera that costs $1700 and then make a comparison. The Nikon D300 would be a fair comaparson; not a 1D mark III, 1D mark IV, D3, or D700.

You also seem to have more problems with focus then others I have seen on the net. I do not claim to be a pro, or a highly skilled birder. But I am not seeing the problems you had with the 7D.

[Bill McCrystyn]

Bet money Luminous Landscape's Michael will have that comparison soon. They always do a very through objective comparison. Their prior tests put me over the fence when I got my D300. None the less, Arash's run still represent what the camera is doing or perhaps, what it's not. It's new and I am sure more tests will come.

http://www.luminous-landscape.com/re...-d3-d300.shtml

[arash_hazeghi]

Arash, thank you for this detailed report. From your description and examples it is evident that BIF against a busy BG is certainly a challenge for the 7D, but if you note I have always praised the IQ of 7D given its sensor size and price, so credit to Canon where it is due. My only input is the fact that the comparison is between the 7D at $1,700 and the Canon 1 DMK3 ($2,000+ more when newly released) and Nikon D700 ($1,000 more). So, while I agree that your conclusions represent actual performance differences it is in a way not quite a completely fair comparison. On the other hand your comparison to the Canon 40D and 50D seem more relevant as they are the same class of camera.

Please receive my comments in the light of constructive input.

Hi Ed,

Your comments are always welcomed and constructive and I totally appreciate it :)

The goal here was not to compare the 7D with 1DSMKIII or D700, the IQ of those cameras alone is head and shoulders above 7D especially in low light, which accounts for difference in sensor size and price, however If you notice I have always praised the IQ of 7D given its price and sensor size/pixel density, so credit to Canon where it is due. The goal was to show that there was a particular problem with tracking raptors against foliage in the conditions mentioned. If it was the case that more expensive cameras had 80% keeper ratio and 7D had 40% keeper ratio that was understandable, the issue was 7D seemed to have a flaw not allowing it to grab focus in these conditions.

Also note that Canon CPS considers the 7D a fully functional and professional product and thus provides exclusive support for it just like the 1D series, in fact I have submitted a collection of samples to CPS per their request for evaluation, I will post their response whenever I hear from them. 1DMKIII AF is three years old now, and I expect after three years of R&D a brand new AF system in the flagship crop DSLR to surpass that of a previous generation model or at least perform equally as good. For example you can buy a Nikon D700 today for $ 2449 from B&H and yet it has the same AF system of the $5K D3/D3X. I am sure Canon marketing has studied the facts throughly and concluded what is best for the company and its shareholders and that's the only thing that matters from their perspective and they are absolutely rightful in their decision.

Also please note that the issues I explained were relative to my subjects and conditions, they do not necessarily apply to other subjects and/or conditions as I stated in the beginning of the summary as well as in the conclusion.
I do recommend people get a 7D and test it in the field to see if it is the right tool for them, all that matters at the end of the day is that if it is producing the photos that you like or not.

Thanks for your comments and insights again.

[Ed Cordes]

Thank you, Arash. I completely understand your explanation. Again, we all appreciate your effort to inform us of your findings. It will be very interesting to hear what CPS has to say.

[John Blumenkamp]

1DMKIII AF is three years old now, and I expect after three years of R&D a brand new AF system in the flagship crop DSLR to surpass that of a previous generation model or at least perform equally as good.

Arash, when you said 'previous generation model' did you mean the 1DMIII, or the XXD series?

[arash_hazeghi]

Arash, when you said 'previous generation model' did you mean the 1DMIII, or the XXD series?

John, my standards are probably hight but I expected the 7D to be heads and shoulders above the XXD (Canon 50D is still in production and sells for just under $1000) and at least as good as a healthy MKIII :)

[Bill McCrystyn]

In all fairness, my D300 AF does not lock up in area-mode (not that I use it much with birds) quite as fast as my friends D700 and so consideration does have to be given to cost/price effectiveness. There is no free lunch. Nothing I must say how-ever is more frustrating than to drop your lock midway in tracking or to lock on a fuzzy image. It does seem the two companies have quite different approaches to marketing.

[Flavio Rose]

1DMKIII AF is three years old now, and I expect after three years of R&D a brand new AF system in the flagship crop DSLR to surpass that of a previous generation model or at least perform equally as good. For example you can buy a Nikon D700 today for $ 2449 from B&H and yet it has the same AF system of the $5K D3/D3X. I am sure Canon marketing has studied the facts throughly and concluded what is best for the company and its shareholders and that's the only thing that matters from their perspective and they are absolutely rightful in their decision.

My expectations were different. I had hoped (but not really expected) that the 7D would have received a dumbed down version of the 1D2 AF system. That would have been a "D300 killer," providing a tried and tested AF system combined with better pixel density and at a lower price. If you have written firmware, you know how easy it is to slow something down by inserting code in appropriate places. Engineering cost is minimal. Parts cost could have been high, however, because of a delicate AF optical path and relatively large AF sensor chip.

What instead we got was a 21 point AF system in which color is seemingly used to compensate for the lack of points, which you have suggested is the technical reason for the poor performance you observed with cryptically colored BIF. Now, I would imagine the main market for good AI Servo is sports, and maybe color compensates for the lack of points very well there. After all athletes don't wear cryptic coloration, they wear brightly colored jerseys (leaving aside occasional odd sports like women's beach volleyball). What bugs me a bit is that there isn't a compatibility mode in which the system works just like the 50D's, with no color used.

[Jim Fenton]

I'm currently using D300s bodies and they are every bit as fast / good rrelative to AF as the $2700 D700 and the almost $5K D3. I've been using all 3 and I find no differences whatsoever. (is whatsoever a real word?)

[Bill McCrystyn]

I agree Jim. What-ever dude. :D

It looks to me like Canon is still playing catch up, at least in the DX arena. The new MKIV on the other hand sounds more promising.

Of course I'm one of those scratching their head as to who wants a goofy half-*** Nikon video system in your DSLR ???? Apparently they think someone does.

[Doug Brown]

I've shot 8,000 frames with the 7D and I've yet to formulate my final opinion on its AF. It takes a long time to figure out how to use a substantially new AF system, particularly one with so many new options. I've not been disappointed in the slightest with the 7D's AF so far, but I'll be at the Bosque in November and California in December doing flight photography against varied BGs. After that I'll feel comfortable rendering my own verdict.

[Fabs Forns]

I'm currently using D300s bodies and they are every bit as fast / good rrelative to AF as the $2700 D700 and the almost $5K D3. I've been using all 3 and I find no differences whatsoever. (is whatsoever a real word?)

Jim, I did find a considerable difference in AF acquisition between the D300 and the D3.
Reasonable, if you consider the price difference.

[arash_hazeghi]

I've shot 8,000 frames with the 7D and I've yet to formulate my final opinion on its AF. It takes a long time to figure out how to use a substantially new AF system, particularly one with so many new options. I've not been disappointed in the slightest with the 7D's AF so far, but I'll be at the Bosque in November and California in December doing flight photography against varied BGs. After that I'll feel comfortable rendering my own verdict.

Looking forward to shooting raptors with you in December as well as hearing your thoughts and verdict.

[arash_hazeghi]

My expectations were different. I had hoped (but not really expected) that the 7D would have received a dumbed down version of the 1D2 AF system. That would have been a "D300 killer," providing a tried and tested AF system combined with better pixel density and at a lower price. If you have written firmware, you know how easy it is to slow something down by inserting code in appropriate places. Engineering cost is minimal. Parts cost could have been high, however, because of a delicate AF optical path and relatively large AF sensor chip.

What instead we got was a 21 point AF system in which color is seemingly used to compensate for the lack of points, which you have suggested is the technical reason for the poor performance you observed with cryptically colored BIF. Now, I would imagine the main market for good AI Servo is sports, and maybe color compensates for the lack of points very well there. After all athletes don't wear cryptic coloration, they wear brightly colored jerseys (leaving aside occasional odd sports like women's beach volleyball). What bugs me a bit is that there isn't a compatibility mode in which the system works just like the 50D's, with no color used.

21 points is still plenty, all I need is only ONE good AF point that holds focus on the subject.
Also I have no field experience with D300 and cannot comment on that body.

[Tony Whitehead]

I have found a significant difference between D300 and D700 in terms of focus acquisition and lock - would be interested to know if the D300s is significantly different to D300.

[arash_hazeghi]

I have added a short video that shows the field conditions and the flight pattern of the harriers here.

Sorry for lousy hand holding and manual focus.

[Ed Cordes]

Thanks for posting this Arash. It is very interesting to see how close to civilization these raptors live. It also shows how hard it is to do BIF photography. I thought I was the only one who has trouble following this type of bird. ;)

[Christopher C.M. Cooke]

Thanks for posting this Arash. It is very interesting to see how close to civilization these raptors live. It also shows how hard it is to do BIF photography. I thought I was the only one who has trouble following this type of bird.

Well done arash! My attempt at using my 5DMKII in video on Harriers yielded some superb footage (much better than yours) but unfortunately did not include any footage of birds but wonderful footage of the sky and fresh air and I got dizzy enough to fall on my a** a few times.:)

My advice, dont try what you did with a 500 f/4, keep going and any feed back would be very welcome.

[arash_hazeghi]

Well done arash! My attempt at using my 5DMKII in video on Harriers yielded some superb footage (much better than yours) but unfortunately did not include any footage of birds but wonderful footage of the sky and fresh air and I got dizzy enough to fall on my a** a few times.:)

My advice, dont try what you did with a 500 f/4, keep going and any feed back would be very welcome.

Lol, I agree it's really hard to hold a SLR with a huge telpehoto like a point and shoot camera and try to follow birds using the rear LCD! If you are on tripod and find a nice perched bird video is worth a try though. Here I just wanted to show the erratic flight pastern of the harriers. Here is another lousy video

I will also add more examples and comments to the article later tonight.

[Christopher C.M. Cooke]

arash, I am going out tomorrow to try with a few lenses from my 24-70 f/2.8, 100 f/2.8, 135 f/2, 70-200 f/4, 300 f/4, 400 f/5.6, the last two on tripods and the others hand held and monopod.

If I don't fall off the cliff I will post results.:)

[Bob Jefferson]

Jim, I did find a considerable difference in AF acquisition between the D300 and the D3.
Reasonable, if you consider the price difference.

Jim said D300"s". I think there is a difference in AF speed between the D300 & D300s according to what I have read also.

[IanWorthington]

Arash --

There are a couple of people over at

http://forums.dpreview.com/forums/re...ssage=33609739

who think that fm 1.1.0 *may* improved/changed focusing.

Big pinch of salt required, but maybe worth a try?

i

[arash_hazeghi]

Arash --

There are a couple of people over at

http://forums.dpreview.com/forums/re...ssage=33609739

who think that fm 1.1.0 *may* improved/changed focusing.

Big pinch of salt required, but maybe worth a try?

i

Thanks Ian, weather and time permitting I might be able to go shooting this weekend, I will remember to flash the new firmware. I would be very skeptical about dpreview.com 99% of the material on that forum is garbage.

Best,

[phillane]

Arash


I found your review of the 7D honestly refreshing, informative, concise and well thought out. Shooting raptors in flight is no small order and regardless of the system I have not found one that is fool proof or on task 100% of the time. The issue you encountered with capturing Raptors in flight principally occurred when the background color was very close or similar to that of the hawk, falcon or what have you, yes? Could this account for a lack of overall contrast in the scene between the subject, background or foreground?




Many thanks



Phil/ aka Denny

[arash_hazeghi]

Hi Phil,
Thanks for your comments. Yes, as mentioned in the summary in the cases where AF failed raptors had similar color compared to the BG. The raptor itself still plenty of contrast but similar color with BG somehow fooled the AF system. What was striking though was that the mentioned 1DSMKIII as well as the Nikon apparently had no particular issue in these cases locking on the bird when the focus point was kept on it, the 7D seemed to struggle too much in comparison. There is a link in the summary to the photos taken with 1DSMKIII for comparisons. In order to get best results from 7D raptor has to fill the entire 19-point AF area such that the AF sensor will not have a chance to "see" the BG.


Best,
Arash