canon 500d and the AF (I guess)

Starastin

Starastin

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hi all !

First of all - I utterly love the 500d although there are no manual controls in the video and some other bits .

but this bothers me the most I guess -

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I'm addicted to street candids, and this chap was basically standing next to me , I used the split second when I felt that he won't notice that I snapped him, but as from such super fast movements the image is not sharp.

not all of them are as such. just some. if I remember correctly the settings where - iso400, f2.2 and 1/160 - I think fair enough for it to be sharp .
or should I use smaller file sizes as I think that 15mp or so with this small sensor is a lot if not too much .

would I be better of with the 60d ?
can't stretch to 5d or 7d but the camera must have a video in it.
what I've read that the 60d is not much of an upgrade from 550d and that the 18mp is too much .


any thoughts ?


regards,
D.
 
So what you're saying is that the reason it's blurry is because you were moving the camera too quickly when you took the shot?

If that's the case then no, a different body won't help, it's all down to technique I'm afraid! You could have upped the iso a little, to reduce shutter speed so the fast movement would have had less effect, but I wouldn't have thought it was anything to do with the number of megapixels.

Another thing to think about is that f/2.2 the depth of field is pretty small. So moving the camera very quickly could lead to the subject not really being in focus.

I can't see how new kit would help, just practice I think. If I've completely misunderstood your problem though, just say!

Chris

Edit: Just re-read the title, to me it doesn't look like an AF problem, it's hard to tell with a small file, but I'd say it looks more like motion blur than being out of focus?
 
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Its just motion blur, nothing more nothing less. New gear wont solve that.
The file size is fine, again that wont have any impact on this. Even at 1/160, the movement of the camera has been picked up. The only way to combat this, is a higher shutter speed, and more practice.
 
thnks guys !

I was about to ask about the shutter speeds.


that's the thing ! - i think I've had enough practise in my life with dslr's . I've shot Nikons Sonys and Canons, but this one feels a bit slow . I'm used to lifting my camera really fast to shoot. the 50mm f1.8 is slow but I work with that . here I think it's still the camera and I refuse to be slower. I just can't afford it ! well in streets I can't .

I still think it's down to image size, too much info to be written down in such split second.
hopefully tmrw I'll try to shoot the streets my style but only using about 6mp of the camera or so.
 
It has absolutely nothing to do with the megapixels on the sensor! Lowering the file size will do nothing. As already mentioned it's shutter speed and focus speed pure and simple. Just up the iso, the 550d has excellent high iso even at 1600. Reducing the file size will no nothing other than lowering your final resolution.

Also the ef 50mm is very slow to focus which won't help.
 
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Essentially you were firing from the hip so to speak, the ef 50mm is just not quick enough for that!
 
The time it takes to write the file is irrelevent , as once taken, its imediately sent to the buffer and the camera can take another shot. Stick the camera in High speed mode and you will see that the camera can shoot 3.4 FPS upto 170 JPGs at a time. The fastest speed on this camera is 1/4000 of a second. If it can find time to write a file in the space of time, then 1/160 is going to be no problem!

The issue is purely your shutter speed was too slow. Yes the 50mm wont help matters as its not a very fast focus lens, to solve that you will need to buy a lens with the USM motor.
 
odd jim said:
Essentially you were firing from the hip so to speak, the ef 50mm is just not quick enough for that!
Click to expand...

I think I just need that f1.4 :(

TCR4x4 said:
The time it takes to write the file is irrelevent , as once taken, its imediately sent to the buffer and the camera can take another shot. Stick the camera in High speed mode and you will see that the camera can shoot 3.4 FPS upto 170 JPGs at a time. The fastest speed on this camera is 1/4000 of a second. If it can find time to write a file in the space of time, then 1/160 is going to be no problem!

The issue is purely your shutter speed was too slow. Yes the 50mm wont help matters as its not a very fast focus lens, to solve that you will need to buy a lens with the USM motor.
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silly me ! doesn't it sound obvious ? :lol:



thanks chaps !
 
Definitely looks like motion blur, rather than focus. So you need one or more of:
- a higher ISO (easy, but some risk to quality)
- a faster aperture (which may mean a new lens, and risks missing focus more easily if you're in a hurry)
- a stabilised (IS) lens
- a heavier lens (which may be easier to hold steady)
- more time (to get yourself into a steady position - and it might just be a fraction of a second more that you need)
- flash (but probably not as discree anymore!!)
- brighter places to take photos

Lots of options, but none are necessarily ideal in any given situation, just need to balance them all for each photo, which i guess will come with practice.

David
 
another thing !

if I put it in auto iso + AV mode , it likes to leave the iso at 100 unless the shutter speeds are not slower than 1/60th . can I hack the camera to make that min shutter speed 160 ?
I was just in Malta and the dynamic range differences were super massive (indoors, outdoors, shadow,sun etc (amazing how you can get used to low DR Britain)) so I couldn't really shoot Tv mode @ 160 all the time + I had to enjoy the stay as well. not resetting the camera all the time
 
No, Canon's auto ISO is strange.
You need a Nikon to do that!

I can set my D700 to automaticly use up to any ISO I want when the shutter speed falls below a certain speed. I have mine set at 1/30 and the ISO up to 4000. The camera will stay at ISO 200 until the aperture or shutter speed, depending on which mode Im in cant compensate for the light. It will then gradualy increase the ISO up to my set amount to keep the shutter speed at 1/30.
Pretty handy really.
 
well mine won't go below 1/60th unless it has hit it's limit - iso1600 . which is great ! but ! I want the iso to be changed when it goes below 1/160 .

oh ! another thing I remembered ! If I were to shoot tv @ 1/160th it would automatically use max aperture and min iso ! WHY !!! the nifty is not at it's best @ 1.8 ... ehhh !!!
but you can't ask that much from an entry level dslr


Nikon on the other hand ! it's wonderfull .. mine has non if these problems as it's a F100 :lol:
 
got stuck in Tv mode from the sunny place as sometimes it would want to go beyond 1/4000 and below 1/30 in half a minute.

ehh ! It's just sooo much wooork !!! :(

:D



btw , I still want that 60d because of the display + controls over the video .
only thing that bugs me is the 18mp in such small sensor.
 
manualfocus-g said:
Yep, diffraction sets in at f6.8 with an 18mp sensor...eep!
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Eh? How did you work that out?? What you are saying is that quality deteriorates after f6.8, that's simply not true.
 
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the nifty fifty isn't the fastest focussing lens, but a couple of things you can try to help you nail the focus in situations where the subject won't stay still is to use servo focussing - that is, select AI Servo on your camera instead of One Shot and the camera will refocus the lens automatically if the object under focus point moves.

as you've noticed auto iso on the 500d (like it does on the 5d2) conspires against you, so set it manually and for those sorts of shots i'd be trying to keep my shutter speed at 1/500 or faster if possible to freeze the motion.
 
manualfocus-g said:
Google is your friend :)
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Well it's wrong, lol!

Why would canon make a high end camera you can't push past f6???
 
odd jim said:
Why would canon make a high end camera you can't push past f6???
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Probably because no-one will see any difference until the aperture gets smaller than that anyway, and any diffraction effects will probably be negated somewhat by the lens's performance increasing at the same time :)
 
cuthbert said:
the nifty fifty isn't the fastest focussing lens, but a couple of things you can try to help you nail the focus in situations where the subject won't stay still is to use servo focussing - that is, select AI Servo on your camera instead of One Shot and the camera will refocus the lens automatically if the object under focus point moves.

as you've noticed auto iso on the 500d (like it does on the 5d2) conspires against you, so set it manually and for those sorts of shots i'd be trying to keep my shutter speed at 1/500 or faster if possible to freeze the motion.
Click to expand...


I'm really thinking about the 50mm f1.4 now to be honest. I was perfectly happy with the 1.8 until too many indoors etc. it's still the best lens I think - in terms of iq, weight and price in any make etc.
 
odd jim said:
Well it's wrong, lol!

Why would canon make a high end camera you can't push past f6???
Click to expand...



can't remember about the diffraction, but the British journal of photography weren't very happy with the "over crowded" sensor . 18mp on aps-c is too much :(

I don't know any other options. but then again if I want to start shooting more seriously (the videos), dslr price will be least of my worries .
 
Starastin said:
can't remember about the diffraction, but the British journal of photography weren't very happy with the "over crowded" sensor . 18mp on aps-c is too much :(

.
Click to expand...

if 18 mp on cropped was such a portent of doom then the 7d would have taken the ditch quite some time ago
 
chris321 said:
Probably because no-one will see any difference until the aperture gets smaller than that anyway, and any diffraction effects will probably be negated somewhat by the lens's performance increasing at the same time :)
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reread the article, they also mentioned the diffraction past f6, which is sad :(



p.s. back on the topic - I think I was used to using the old dslr's etc :cuckoo:
having much better results with centre AF .
 
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