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450d vs. 40d - which is better for focus accuracy?: Canon EOS 1000D / 450D - 300D Forum: Digital Photography Review
I suppose this has been debated but I've not been able reaching a conclusion.
From experienced users, which of the two cameras (40d and 450d) performs better for what is concerning the accuracy of the AF?
Thanks
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This is what Rob Galbraith used to say about the 20D/30D (now on 400D/450D) AF:
From http://www.robgalbraith.com/bins/multi_page.asp?cid=7-7891-8214-8216
"More importantly, we've shot the D200 and 20D side-by-side for available light basketball over several weekends this winter, and the 20D is by far the better camera for this purpose.
Not only were the ISO 800 through ISO 3200 frames massively cleaner and more usable, the percentage of in-focus frames was signficantly higher.
In fact, we've ruled out using the D200 for this sort of assigment again."
He sounded reasonably impressed with the 20D AF at that time.
But his current report on the 40D AF does not sound promising at all: http://www.robgalbraith.com/bins/multi_page.asp?cid=7-8740-9068-9537
And this is what Imaging Resource has to say about the 40D AF as compared to the 20D AF:
From http://www.imaging-resource.com/PRODS/E40D/E40DA.HTM
"In horizontal mode, Dave had a heck of a time getting the Canon 40D's top center AF point to focus on Marti's hair during the indoor shots.
Hair isn't the best place to focus, of course, but it works well enough when we do it with other cameras.
In Dave's case, the camera said it was in focus, but it was either front- or back-focusing.
When shooting a soccer match in AI Servo mode recently, the Canon 40D had a hard time finding and keeping focus on my subject.
It was usually okay if I could keep the player over the center point, but not always.
It still randomly focused many yards behind a player for one frame, then snapped back to proper focus, then back out.
Soccer is an extreme example -- and I am spoiled by shooting the 1D Mark II N, and even the 1D Mark III -- but the 20D does better than the 40D in these situations.
I got better results shooting in AI Focus mode, which is probably more appropriate for a more random movement game like soccer."
In my experience, for single shot focus with the center AF point, there is not much to choose from between the 40D and 450D.
The key is to ensure the camera and lenses are appropriately calibrated.
A View through my Lens
thw.smugmug.com
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Thanks for interesting links, thw.
Imaging Resource continues:
"Despite my problems with autofocus as mentioned above, I generally shoot with a single AF point selected;
And mostly that's the center AF point.
I haven't had nearly the trouble I had with the multi-point mode selected.
In low light, the Canon 40D outperforms the EOS 20D and Rebel XTi.
The 20D and 30D do better than the XTi with the same subjects and same lens, and the 40D bests them all.
My former extreme test subject of a person in light from a television proved the 40D better than all three.
Testing in the lab proved that the EOS 40D does even better than the company claims, focusing accurately at less than -0.5 EV (1/4 foot candle), all the way down to 1/16 foot candle, the lowest light level we test.
Of course, that's with a high-contrast black and white test target, and we have no way of knowing what Canon's test conditions are."
"In summary, I've found the Canon 40D's AF system to be stronger in some ways and weaker in others when compared to the more predictable 20D and 30D AF system.
I got more consistent results in single-point AF mode."
http://www.imaging-resource.com/PRODS/E40D/E40DA.HTM
--
I once tested 450D and 40D side by side for a few hours.
My testing was very far from scientific, didn't even use several lenses, but I felt that 40D sometimes focused slightly faster in low light.
I didn't notice any difference in the actual focusing accuracy thought.
I still think that the major difference is that all 40D's nine AF sensors are cross-type while 450D has only one (center) cross-type sensor.
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Quote: :
> When shooting a soccer match in AI Servo mode recently, the Canon 40D
>
Had a hard time finding and keeping focus on my subject.
It was
> usually okay if I could keep the player over the center point, but
>
Not always. It still randomly focused many yards behind a player for
>
One frame, then snapped back to proper focus, then back out.
Soccer
> is an extreme example -- and I am spoiled by shooting the 1D Mark II
>
N, and even the 1D Mark III -- but the 20D does better than the 40D
>
In these situations.
I got better results shooting in AI Focus mode,
>
Which is probably more appropriate for a more random movement game
>
Like soccer."
>
That sounds like my 350d.
And I use AI Servo.
Maybe I need to try AI Focus.
Shooting soccer is one of the main reasons I want to upgrade my 350d to something that focuses better.
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I don't know about what bloggers say, but in my experience the 40D is in a different league compared to the 350D.
Low light AF is much better, accuracy is better (within 1/3 dof at f/2.8 and below compared to 350Ds within 1 dof, I've tested it and it is indeed true in reality).
Also, the 40D needs less detail to succesfully AF.
The only time I had troube focusing was with shooting in candle light.
Using just one candle seems to be hard on the AF sensor.
Using two candles fixed that problem though.
But really, with those kind of low light shots, I was hardly able to see the subject through the viewfinder.
The 350D would not AF at all, it just hunted back and forth.
I'm talking about light levels of about 1600 iso, 1/30ss f/1.8 to f/2.8.
I've found the cheapo 50mm f/1.8 much more usable on the 40D than on a 350D when shooting shallow dof shots.
Fast primes are more hit and miss affair on the 350D while the 40D is spot on 95% of the time.
I gave both a real workout shooting ballet in low light.
I've shot about 5000 shots with both camera's and the 40D had about 95% keepers, the 350D about 50%, much more oof.
So I've limited the 350D to use the sigma 18-50mm f/2.8 at f/4, at wide angle and AF for the whole ballet stage and switched to manual AF.
AF on the 350D improves in good light though.
The AF performance with short tele primes like 85mm f/1.8 is much better on the 350D than shorter primes like 30mm.
Same thing goes with the sigma 18-50, 18mm is less accurate than 50mm.
So I zoom in, AF, zoom out a lot if I want to be sure.
Not so with the 40D, it's bang on target even at wide focal lenghts.
I've seen reports that the 400D is an improvement over the 350D, and the 450D is an improvement over 450D.
So the 450D should be noticeably better than the 350D, esp.
With the 2.8 center AF sensor.
For better and candid/fast pace shots it's better to be able to use an off center af point and being able to very quickly select it using the stick on the 40D.
It's great for event photography.
It's almost as accurate off center as the center af point.
Sometimes even more accurate as the center AF zone is bigger than the off center ones, getting less confused where to AF.
I'd like to know if the 450D + lenses <
35mm AF well in low light at f/1.4 to f/2.8.
Quote: :
>
>
Quote: :
> >
When shooting a soccer match in AI Servo mode recently, the Canon 40D
>
> had a hard time finding and keeping focus on my subject.
It was
> > usually okay if I could keep the player over the center point, but
>
> not always. It still randomly focused many yards behind a player for
>
> one frame, then snapped back to proper focus, then back out.
Soccer
> > is an extreme example -- and I am spoiled by shooting the 1D Mark II
>
> N, and even the 1D Mark III -- but the 20D does better than the 40D
>
> in these situations.
I got better results shooting in AI Focus mode,
>
> which is probably more appropriate for a more random movement game
>
> like soccer."
>
>
>
> That sounds like my 350d.
And I use AI Servo.
Maybe I need to try
>
AI Focus. Shooting soccer is one of the main reasons I want to
>
Upgrade my 350d to something that focuses better.
--
Kind regards
Imqqmi
Image control: Zoom out | Zoom 100% | Zoom in | Expand / Contract | New window
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Actually I own a 350d and I always had problems with AF accuracy.
I went many times (7) to the Canon Service but the focus simply was moved from front to back to front etc.
But never in the DOF.
( i don't want perfect focus, just inside the DOF).
I've read many posts claiming about successful focus calibration.
I suppose it depends from the service.
At last I reached the conclusion that it will be impossible to have a good focus on my camera.
When I do a portrait, now I just focus on the ear, to have the eye in focus.
Or I avoid using 2.8 (but that's what justify the lens cost!).
I'm not speaking of low-light etc.
Just perfect focus condition.
Center focus point, good light, good contrast etc.
In these years I've become an expert in measuring AF.
There are things that confuse the AF, like patterns, or leaves etc.
I avoid all these to judge AF.
And I don't care of the results of focus test.
I use focus test just to confirm the seriou issues I see in the field (today I throw away about 50% of photos) but the others are OK.
So, the worst thing could be if I buy a new camera just for AF, and then I still have problems.
That's why I'm posting.
Reading replies, it seems to me to have understood that 450d, due to its low costs, can give a higher risk of AF unaccuracy (I suppose a lower quality control).
Of course many people are satisfied.
There are always satisfied people.
But I learned one thing from the forum: If the forum finds an issue and this issue is confirmed by many people (even if not the majority) then, when I buy, I find the issue.
And always there are people saying that they are ok etc...
It always happened to me, for cameras and lenses.
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Quote: :
> Or I avoid using 2.8 (but that's what justify the lens cost!).
May I know what f/2.8 lens you were using ?
My experience with 40d + f/2.8 lenses were not quite rosy, most of the time it grabbed the right spot, but every now and then I end up with totally blur pics - which later on I found out were focused wayy in front, near my shooting position.
The annoying part is that I got those $$ lenses after successful shots with slower ones (kit + 28-135).
And 3rd party / sigma normal 2.8 zooms were simply useless, while they worked great on a 30d.
Seems like there's a glitch in this extra sensitivity area which doesn't show up on slower lenses, and strangely, also no problem with primes.
I always use center spot +SS, and body/lenses already calibrated.
Very confusing ...
>
And I don't care of the results of focus test.
I use focus test just
>
To confirm the seriou issues I see in the field (today I throw away
>
About 50% of photos) but the others are OK.
Mine was probably 10% but still I found them disturbing considering the costs involved.
>
It always happened to me, for cameras and lenses.
Lol ...
Same here. However, as a last attempt before going back to 30d, I tried 450d, and surprisingly initial test shots with same lenses were very promising (already sold the sigma).
Hopefully this is my lucky break and if interested I can update you later on.
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It seems mr murphy doesn't do you any favors ;)
Every camera batch has some lemons, it's a fact of life.
I think many here on the xxxD don't use fast lenses, pixelpeep, and do fast paced shoots with/of people in low light.
Those who do either have low expectations and shoot a lot of redundancy to get at least a few usable shots or have high expectations and run into the limits of the xxxD series camera's.
I've about had it with the AF performance of the 350D, it just doesn't cut it in that (admittedly difficult) situation, only in certain situations like the fixed distance of the signing of the paper.
I focus once, check focus by zooming in, switch to manual focus and shoot away knowing that all shots will be in good focus.
That's why I knew I wouldn't settle for anything less than the 40D.
It has not let me down yet.
Extra care needs to be taken for critical shots like moments that will not happen again such as graduation shots.
The 40D just delivered which should be expected from a semi pro camera.
Don't get me wrong, I very much like the 350D, but the AF isn't perfect.
The 40D isn't perfect either but comes a lot closer.
I'm looking to replace the 350D with something that's as good as 40D or better.
I'm currently eyeballing second hand 1D mk II which can be had relatively cheaply.
A lot of new 1D mk III owners are selling that camera now so now's the right time.
It's great to have a second body during shoots and events, I'd like to have one that's as reliable as the 40D without having to shoot something 3 times.
I really have to unlearn the 'refocus and shoot' 3x thing I use on the 350D with the 40D, it just gets me 3 perfectly in focus shots that look exactly the same.
Long story short, if you are done with bad AF in very demanding conditions, and I know you do, get a 40D or better camera.
If you believe you get a lemon, send it in or get another body, it's worth the trouble.
Better yet let someone else buy the camera for you ;)
Quote: :
>
Actually I own a 350d and I always had problems with AF accuracy.
>
>
I went many times (7) to the Canon Service but the focus simply was
>
Moved from front to back to front etc.
But never in the DOF.
( i
> don't want perfect focus, just inside the DOF).
>
>
I've read many posts claiming about successful focus calibration.
I
> suppose it depends from the service.
>
>
At last I reached the conclusion that it will be impossible to have a
>
Good focus on my camera.
>
When I do a portrait, now I just focus on the ear, to have the eye in
>
Focus.
> Or I avoid using 2.8 (but that's what justify the lens cost!).
>
>
I'm not speaking of low-light etc.
Just perfect focus condition.
>
Center focus point, good light, good contrast etc.
In these years
>
I've become an expert in measuring AF.
>
There are things that confuse the AF, like patterns, or leaves etc.
I
> avoid all these to judge AF.
>
And I don't care of the results of focus test.
I use focus test just
>
To confirm the seriou issues I see in the field (today I throw away
>
About 50% of photos) but the others are OK.
>
>
So, the worst thing could be if I buy a new camera just for AF, and
>
Then I still have problems.
>
That's why I'm posting.
>
>
Reading replies, it seems to me to have understood that 450d, due to
>
Its low costs, can give a higher risk of AF unaccuracy (I suppose a
>
Lower quality control).
>
Of course many people are satisfied.
There are always satisfied people.
>
>
But I learned one thing from the forum: If the forum finds an issue
>
And this issue is confirmed by many people (even if not the majority)
>
Then, when I buy, I find the issue.
>
And always there are people saying that they are ok etc...
>
>
It always happened to me, for cameras and lenses.
>
--
Kind regards
Imqqmi
Image control: Zoom out | Zoom 100% | Zoom in | Expand / Contract | New window
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The focus engine in the 40D is higher quality and faster.
At 6.5 fps, it needs to be dead on.
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Quote: :
> May I know what f/2.8 lens you were using ?
Mainly 24-70 2.8L.
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Quote: :
> At 6.5 fps, it needs to be dead on.
Yup, it needs to be.
However in my experience it somewhat failed in real life shooting.
Sure it focused faster, and more sensitive in low light, almost no hunting compared to 30d, but my ratio of oof shots are certainly higher than what I got through 450d with same lenses.
Ironically 40d seemed to be more twitchy with f/2.8 zooms.
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Not my experience.
Which lens were you using?
Using L glass (70-200 2.8 IS), I had almost 100% take rate.
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Quote: :
> Mainly 24-70 2.8L.
Ouch.
Anyway, from same test location today I'm glad to report that 450d only missed very few shots and thankfully none on 'easy targets'.
Its AF is still more prone to be tricked compared to 40d though, perhaps sensor placement was not perfectly aligned with AF spot on VF, while 40d continued to grab correct target through branches or nearby objects.
So relieved to finally find that 17-55 (as well as kit 18-55) performed as expected on distant objects.
Looking back, I think 40d is more demanding or has less tolerance on lens condition that is used.
It doesn't like any slight misalignment inside (which probably passed service center's alignment tolerance) whereas 450d or lesser bodies are happy enough to land their focus point within 'deeper' area.
Hopefully I make some sense here, and as usual sorry for my poor English.
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Quote: :
> not my experience.
Which lens were you using?
Using L glass (70-200
>
2.8 IS), I had almost 100% take rate.
Most problem shots were taken with 17-55 is, smaller portion with 70-200/2.8 non IS, and very difficult to get sharp shots with 135+1.4 TC.
Sigma standard 2.8 zooms are as good as useless and tamron 28-75 missed clear targets.
What made me scratch my head:
1.
Lenses worked fine with other bodies (135 +TC is prime-like with 450d)
2.
No problem with slower lenses (kit, 28-135) - and - normal primes (35-50-85).
Countless trips to service center with body and lenses, found nothing wrong.
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My XSI focuses quicker and more accurately than the 40D I've owned since Aug.
2007. There is nothing wrong with my 40D.
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I have got both of them, without any hesitation the 40D
The AF in 450D is probably the only weak point that comes from canon middle ages period : not very sensitive in low light and mainly in low contrast situations, not fast enough as well for sport or wildlife with lenses that are not USM.
(where 40D gives good results)
Also the viewfinder although improved not as clear as 40D)
Robert
:--)
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Quote: :
> I have got both of them, without any hesitation the 40D
Interesting how we got mixed results here.
;-)
I'm done testing: not a single missed focus coming from 450d with 50/1.4 wide open.
In addition, not sure how canon increased jpeg sharpness on 450, but with similar settings (+1 or 4), I saw sharper and more contrasty pics at 1.4.
So 40d is now in the hand of its new owner.
;-)
One thing I already miss from 40d is its 'confident' shutter sound and firm grip (ok that's two).
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Quote: :
> Quote: :
>
> I have got both of them, without any hesitation the 40D
>
>
Interesting how we got mixed results here.
;-)
I know, maybe you have a lemon 40D.
>
>
I'm done testing: not a single missed focus coming from 450d with
>
50/1.4 wide open.
In addition, not sure how canon increased jpeg
>
Sharpness on 450, but with similar settings (+1 or 4), I saw sharper
>
And more contrasty pics at 1.4.
So 40d is now in the hand of its new
>
Owner. ;-)
Any sample (action) shots came from your XSi, that's really impressive?
Here's mine, taken with 40D.
http://forums.dpreview.com/...
...sp?forum=1019&message=28827725&changemode=1
>
One thing I already miss from 40d is its 'confident' shutter sound
>
And firm grip (ok that's two).
I still like the shutter sound of my XTi, but I like the grip of my 40D specially when my external flash attached.
--
Rod
40D, XTi cameras.
Canon EF 70-200mm f/4 L IS.Tamron 17-50mm f/2.8 SP and 90mm f/2.8 SP macro lenses.
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