Canon EOS 550D AF performance

[paulo_cortez]

<p>Hi,<br /> I'm considering buying a 550D as a back-up for my 5D but after some bad experiences with 400D and 450D AF performances, I would like to have some opinions about this aspect from 550D owners, preferably who also own EOS pro or semi-pro bodies or who owned the referred bodies.<br /> I'm asking this as I had some photos ruined (in some cases, near half) due to poor AF performance during, for example, some friends weddings with good light, contrasty subjects and fast lenses.<br /> Curiously (or not), the worst results involved lenses like the EF 24-105mm f4L and EF 24-70mm f2.8L, which have very good performance with the 5D. BTW, none of these lenses is doing back or front focus.<br /> Thanks for your help,<br /> Paulo</p>

[paulo_cortez]

<p>I've noticed now that there's a thread from Jan Kowalsky referring to Canon 's bodies AF performance - http://www.photo.net/canon-eos-digital-camera-forum/00Wy9S. Anyway, I just would like to have your opinion about 550D AF performace - that's it.</p>

[faysal]

<p>Paulo, can we see some examples of the images you are talking about?</p>

[mbkissel]

<p>Well, I don't know what you're really expecting to hear. My wife uses a 550D all the time and hasn't complained about the AF performance. I've personally used the other two cameras you mentioned without AF problems.</p>

[paulo_cortez]

<p>F5.6 and 1/200 - only the flowers are in focus</p>

[paulo_cortez]

<p><img src="http://i869.photobucket.com/albums/ab255/digivet/IMG_6663.jpg" alt="" /></p>

[paulo_cortez]

<p>In this wedding, for example, I was shooting from from about 4 meters, with a 450D+24-105mm f4L, pointing at their eyes and half of the shots were unusable. This wandering focus issue occurred frequently in similar situations. Although less prone, this also happened with the 400D.</p>

[buffdr_rasouliyan]

<p>Hi, not only you have a focus issue here but I think the shot was metered wrong. Another words, the shot is over exposed. It appears there is ample amount of light and to be only at 5.6 and the shutter speed of 200? I would think you could have shot this at F8 and shutter speed above 800 easily. From the data I pulled from the picture it states the camera was in Program mode (2). Does this mean you had a custom programed? If the flowers are in focus, then it is front focusing. I would try this again but rather than allowing the camera to pick your settings, for test purposes, manually set the parameters. very interested what caused this. If you figure it out, let us know. Good luck v/r Buffdr </p>

[rubo]

<p>Just curious, did you set the focus point manualy, or was the camera set to choose the focus point?</p>

[mbkissel]

<p>Paulo, from the EXIF data, it appears the camera was in Auto Exposure mode (Green Box Mode). In this mode, the camera is selecting the focus point regardless of where you have it aimed. It will typically assume the closest object to the camera is your intended subject and use that focal point; in this case, the flowers in front.</p>

[brett_w.]

<p>I agree, - learn to use AV, (aperture priority) Tv, (shutter priority) or manual modes and set the AF point yourself. Full Auto mode automatically selects the AF point and in a crowd of people it can be wrong! </p>

<p> </p>

[paulo_cortez]

<p>Hi,</p>

<p>Thanks a lot for taking the time to analyse EXIF data from this picture.</p>

<p>Although I normally use Program mode with manual focus point selection for most type of situations, I guess the settings were different as previously I had lent lend the camera to my wife so she could take some pictures of my son before the wedding ceremony. I vaguely remember looking at the sets to check: speeds above equal or above 1/200 were OK for the focal length and f5.6 allowed to emphasize the fiancées from the crowd behind. If you look at EXIF data, you'll notice that Exposure Bias Value of EV0,0 (obvious for Auto mode), although as Buffdr correctly referred, it's a little bit overexposed - this issue was also frequent when using this lens with the 450D.</p>

<p>Anyway, one thing I remember is that the AF points were blinking over the fiancées for this and many other shots (I wouldn't shoot if they were over the balcony or over the flowers inside the glass jars even if I had drunk too much previously...).</p>

<p>Therefore, I'll keep the first answer from Mark referring the the apparent absence of AF problems with the 550D. Finally and if you allow me, I'll write the following advice to Canon gear owners before buying a new lens: above sharpness, I would first test the AF performance of a lens with it attached to my camera.</p>

<p>Best regards,<br>

Paulo</p>

[brett_w.]

<p>the AF of the 550D, 450D, 400D is similar so if you had problems with the prior two cameras then you might still have problems. Other people get great pics and AF performance from the 450D and 400D. Perhaps it's time to get away from "program mode" and learn a little bit about the cameras ! </p>

<p> </p>

[paulo_cortez]

<p>Brett, sorry but I can't establish a relation between P mode and poor AF performance. Can you?<br>

And I wrote that I use "Program mode with manual focus point selection for most type of situations", not for all!</p>

[brett_w.]

<p>That's it -<strong> blame the camera for your poor pics!</strong><br>

"P" program mode chooses the aperture, shutter speed, ISO which may not be the best choice. There is not "poor" AF, only poor photographers! The 450D, 400D, 1000D, etc. can get great action shots, landscape pics, portraits, whatever. <strong><em>learn to use the camera's functions !</em></strong></p>

<p> </p>

[paulo_cortez]

<p>Dear Brett,</p>

<p>Sorry but you didn't reply to my question:</p>

<p>- What's the relation between P mode and poor AF performance?</p>

<p>I know that these cameras are great as I bought a 450D after owning a 400D, my first digital SLR - my first SLR, 25 years ago, was a Pentax K1000 which, as you know, didn't have Program mode or AF. Most of my lenses are MF (M42, Nikon F, Pentax K, Contax/Yashica, etc.) and, when not using them with the respective film bodies, I attach them through an adapter to my 5D (the large and luminous viewfinder view that makes MF easier was one of the main reasons for it acquisition) and shoot with AV and manual modes, although the rear elements of some of these lenses may collide with the mirror.</p>

<p>Thus not a regular poster in this site, I visit it frequently in search for answers to doubts or questions related to photography. I didn't start this thread to waist the time of the other members of this community who often very promptly and <strong>gently </strong>help me and other members. I know I'm a poor photographer (the chosen picture and my Flickr page, which is only destined to show some of my travel pictures to my family, confirm that) as I don't have the time and talent to produce the overwhelming pictures, which can be found by the thousands in sites like this one, Flickr, Pbase, etc.</p>

<p>Anyway and though you disagree, I think I have some photographic technical notions, at least enough to understand that this AF issue is not related to the used exposure mode.</p>

<p>Take care,<br>

Paulo</p>

[steve_wagner1]

<p>Paulo, from another, possibly more helpful Brett, here are some steps you can take to improve focus and sharpness.</p>

<p>1. Brace well, improve steadiness<br /> 2. Observe golden rule of using a faster shutter speed than the focal length<br /> 3. Use IS well, when applicable<br /> 4. "Focus" intently on the focusing process<br /> 5. Reduce lag time between acquiring focus (the beep) and pressing of shutter, this can be a biggie<br /> 6. Be more aware of subject movement<br /> 7. Experiment with auto ISO, which can be very helpful<br /> 8. Practice using AE lock<br /> 9. Be sure you're only using AI servo when necessary<br /> 10. Use flash when appropriate</p>

<p>These are for hand held. For tripod shooting:</p>

<p>1. Use mirror lockup<br /> 2. Use the self-timer<br /> 3. Use a cable release</p>

<p>Happy shooting!</p>

[wajad_iqbal]

<p>Hi Paulo,<br>

I have owned the 550D since day one and iv had no AF issues, my photos are sharp as ever.<br>

i switch between<br>

18-55 kit lens<br>

50 1.8<br>

75-300mm 3.5-5.6 USM<br>

and 24-85 3.5 4.5 (older lens but great walk around)<br>

http://www.flickr.com/photos/wiqbal/<br>

all my pictures were taken with a 550D and there are pictures in various lighting so you can be the judge of the sharpness here ;P</p>

<p> </p>

[brett_w.]

<p><em>"1. Brace well, improve steadiness</em><br /><em> 2. Observe golden rule of using a faster shutter speed than the focal length</em><br /><em> 3. Use IS well, when applicable</em><br /><em> 4. "Focus" intently on the focusing process</em><br /><em> 5. Reduce lag time between acquiring focus (the beep) and pressing of shutter, this can be a biggie</em><br /><em> 6. Be more aware of subject movement</em><br /><em> 7. Experiment with auto ISO, which can be very helpful</em><br /><em> 8. Practice using AE lock</em><br /><em> 9. Be sure you're only using AI servo when necessary</em><br /><em> 10. Use flash when appropriate</em><br>

<em>These are for hand held. For tripod shooting:</em><br>

<em>1. Use mirror lockup</em><br /><em> 2. Use the self-timer</em><br /><em> 3. Use a cable release</em><br>

<strong>All good suggestions but the OP blames his poor pics on faulty "AF" - not his techniques!</strong><br>

(strange how other people with the same cameras get good pics!)<br>

good luck with that faulty AF 550D !<br>

<p> </p>

[paulo_cortez]

<p>Hi again Brett W.<br>

Thanks a lot for your constructive comments on my photographic technique.<br>

I advise you to reply to this thread: http://www.photo.net/canon-eos-digital-camera-forum/00Wy9S<br>

It looks like Jan also needs your expert advices on how to take great pictures with Canon gear.</p>

<p>Brett Cole: sincerely, thanks a lot for your advices. Although I've taken almost all steps you referred, there was always a clear difference between the 5D and 450D AF performances with certain lenses.</p>

<p>Many thanks to all repliers,<br>

Paulo</p>

[brett_w.]

<p>here's another photography resource for you paulo - http://photography-on-the.net/forum<br>

<em><strong>Hope you get out of that green box auto mode with your new 550D !</strong></em></p>

<p> </p>