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  #1  
Old 23-01-13, 10:34 AM
Jacks76 Jacks76 is offline
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Canon 650d focusing on closest object and 50mm lens

Hi All,

I have just bought my first digital slr camera, the canon 650d, and I am determined to eventually learn how to use it properly!

However, it's a lot to read and learn and so i can start using it straight away I am using the intelligent mode.

I have 2 questions if I may and please forgive my lack of understanding at present!

Firstly, and most importantly the auto focus 9 points system seems to default to always focus on the object closest to the lens. So if for example I take a photo on a person sitting down with something on their lap, a dog, the dog is perfectly in focus and incredibly sharp, but the person is out of focus?

Am I doing something wrong or is this just something that happens in the auto mode?

This is using the 18-55mm kit lens.

Secondly I am considering the EF 50mm 1.8 lens as a first lens for portraits. The cost makes it affordable now. Is this a good starter lens?

Thanks for reading
Jacks76
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Old 23-01-13, 11:08 AM
Jamie.b Jamie.b is offline
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the 50mm 1.8 is a huge step up in terms of image quality over the 18-55. it is however very cheaply made, but for £90 new its not a huge concern. The big advantage of this lens is that its openable up to 1.8, however it is slightly soft here, stop down to 2.2 and the images are much better.

As a second lens its perfect. On a crop sensor it wouldn't seem right as an only lens as it seems zoomed in, to about 80mm which is perfect for portraits, but cumbersome for everyday shooting.

In canons auto mode you cant change the focus point, you could try shooting in P mode. P mode the camera selects the shutter speed and aperture, however you can change these together using the scroll wheel. P mode also allows for the iso and the focus point to be changed. this could help your problem.
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Old 23-01-13, 03:28 PM
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donoreo donoreo is offline
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By default the focus point will be the closest object. See using P mode as recommended above until you get more comfortable and select the focus point you want.
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Old 23-01-13, 04:06 PM
nick_gray nick_gray is offline
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In addition to what Jamie has already mentioned.

The auto-focusing system will try to focus on what is central in the picture or what is closest to the front of the lens. If this isn't what you want, there is a small switch on the side of the lens that you can switch from AF to M (auto-focus to manual) and then use the focus ring to focus where you want. Another method is to put what you want in focus into the middle of the viewfinder, half press the shutter button, let the camera auto-focus, then recompose the shot (which might be fine if it's a quick grab shot where you might miss the action, but isn't recommended as you'll likely be increasing focal length between your camera and the object you are taking a picture of and therefore your focus will be out).

Alternatively, if you change the camera mode out of one of the creative modes or full auto (the green square) onto P, TV, AV or M, you can then manually choose one of the 9 focus points (press the button with what looks like a cross above it - on my Canon 500d it's the same button as the zoom, on the top right of the camera back), you will then see the little red focus light when you look through the view finder, you can move this around the focus points with the scroll wheel, until the red light is over where you want to focus. This is replicated on the rear screen (if you have the display set to show camera settings).

I suspect what has happened with your photo is that the camera has reduced the aperture due to insufficient light, which has given you a shallow the depth of field, which is leaving the dog in focus and the persons face out of focus.

Personally, I'd suggest you play around and get a bit more familiar with your camera and with your kit lens (which is pretty good and gives you a bit more flexibility and a bit of zoom), before getting the 50mm 1.8 (which is a lovely lens and one that I used to take my entry in the weekend competition http://www.digitalcameraworld.com/fo...ead.php?t=9921 GREED)

I hope this helps.

Regards

Nick
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Old 23-01-13, 06:38 PM
wave01 wave01 is offline
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i would get out of the auto mode and use the AV TV or manual then you can choose the focus point or use the centre one and just recompose your shot keeping the shutter button half way down
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Old 23-01-13, 08:34 PM
Jacks76 Jacks76 is offline
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Thanks all for reading and your advice.

Guess its time to venture out of the auto mode and play with the focus points! It's a lot to learn but been something I have wanted to get into for a long time and only now can afford to!

Have ordered the 50mm lens as found a good deal. But will be learning a lot more before choosing the next lens.

Sure there will be more questions as I go and good to have somewhere to ask.

Good luck with competition Nick.

Thanks
Jacks
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Old 24-01-13, 06:51 PM
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wavemachine wavemachine is online now
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I agree with the above posters with regards to getting out of auto mode and whilst I am not addressing your original point I think this maybe useful.

The way I look at it is your camera is intelligent but it doesn't understand what you want from your picture or what it is actually taking a picture of, basically it attempts to focus and chooses a shutter speed, ISO and aperture based on the available light. So you could end up with a landscape with a shallow depth of field or a portrait with a massive depth of field which is probably not what you want.

For example if you shoot in AV you control the aperture so you are deciding on the depth of field, you can also select focus points so you can control the focus.

It seems complicated to begin with but you will get the hang of it with a bit of practice
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