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Thread: Sharp photos - How to Shoot ah?

  1. #21
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    Default Re: Sharp photos - How to Shoot ah?

    Quote Originally Posted by skyhifi
    I will try to take some more photos again and see how it goes. To get sharp photos, do I have to use small apertures, eg 5.6 or more? I usually use large apertures, eg 1.8 to create that blurry effect. Also, by using large apertures I am able to use higher shutter speeds (thinking that my subject will be well focused, getting ride of hand movement effect). But somehow this is not the case.

    Will a camera, in this case 20D, have a focus calibration problem? I really hope not...
    Now I can understand why your image blur. It is due to F1.8 settings. Try using 3.2

  2. #22
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    Default Re: Sharp photos - How to Shoot ah?

    For a medium close up (head and a bit of shoulders) shot, on an 85mm and 1.6 crop, you'll probably be say 8-10feet away from your subject, at f1.8 you'll be looking at a critical DoF of only 2-4 inches. Like what's mentioned, try to shoot at f2.8 or f4 if you wish to keep say more of the face in focus; f1.8 is fine if you're only interested in keeping eyeballs in focus (individual preference; no fault or anything). You might be interested to know that there exist very little or no lenses where the performance is excellent wide open, so stopping down a bit helps somewhat. eg. for 50f1.4, there's a slight glowy feel to the subjects [when shot wide open], so unless I'm going for that look, I try to shoot at f2 minimum.

    Shutter speeds affect steadiness too... usually the recommended is 1/focal length or faster; in your case, 1/85 or faster. Of course, more practice in proper handling techniques helps.

    Other factors could be subject movement or wind and etc...

    edits in []
    Last edited by alexj; 3rd September 2006 at 04:28 PM.

  3. #23
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    Default Re: Sharp photos - How to Shoot ah?

    Quote Originally Posted by alexj
    For a medium close up (head and a bit of shoulders) shot, on an 85mm and 1.6 crop, you'll probably be say 8-10feet away from your subject, at f1.8 you'll be looking at a critical DoF of only 2-4 inches. Like what's mentioned, try to shoot at f2.8 or f4 if you wish to keep say more of the face in focus; f1.8 is fine if you're only interested in keeping eyeballs in focus (individual preference; no fault or anything). You might be interested to know that there exist very little or no lenses where the performance is excellent wide open, so stopping down a bit helps somewhat. eg. for 50f1.4, there's a slight glowy feel to the subjects [when shot wide open], so unless I'm going for that look, I try to shoot at f2 minimum.

    Shutter speeds affect steadiness too... usually the recommended is 1/focal length or faster; in your case, 1/85 or faster. Of course, more practice in proper handling techniques helps.

    Other factors could be subject movement or wind and etc...

    edits in []
    Agree also. What I was advise was always never to use the lowest settings. If it is 1.4, u can use 1.8, If 2.8 lens, use 3.2 to 4. Those are the rough guide as to how the settings shd be

  4. #24

    Default Re: Sharp photos - How to Shoot ah?

    yup. will try more shots with my sister when my 400D and 50mm 1.8 comes

    20D was rented.
    random equipment.
    where are my primes?

  5. #25

    Default Re: Sharp photos - How to Shoot ah?

    Quote Originally Posted by skyhifi
    Hi all. I am using a Canon 20D and Canon 85mm f1.8 lens. I have been having problem trying to shooting images sharply. I usually take shots of people. Even though I aim, half press the shutter to focus accurately at the object/person, and thereafter full press it to take that pic, somehow when I preview it the photo comes out not very sharp. On some occassion I was able to get very sharp images. How come ah?

    I really ensured that I auto focus the object correctly before taking the shot. It's just not as sharp as I wanted it to be.

    I came up with 2 conculsion for this problem:

    1. My hand not steady enough.
    2. Shutter speed too slow (but I do shoot at above 1/300 and it still is not very sharp).

    Could any Pro/Guru help me out, please?

    Thanks in advance.
    I am no guru nor pro.

    I read what others wrote and is in agreement with what was said.

    But let me give another possible reason. I can, IF I WANT, shoot a sharp image with a 80 mm lens at 1.4, manually.

    With this kind of photgraphy like taking a close face image, the moment between achieving focus and tripping the shutter is quite important. So the moment I achieved my focus (where i wanted it), I trip the shutter.

    With a system like what you have, you are relying on the camera's autofocussing mechanism which, unless faulty, is very accurate. But once focus is locked, do not delay, because if you or the subject move, you might have an out of focus image. WIth my manual camera, even if I delay, it matters not, because I do not assume focus is right, and there is no autofocus to trick me.

  6. #26

    Default Re: Sharp photos - How to Shoot ah?

    Quote Originally Posted by skyhifi
    I will try to take some more photos again and see how it goes. To get sharp photos, do I have to use small apertures, eg 5.6 or more? I usually use large apertures, eg 1.8 to create that blurry effect. Also, by using large apertures I am able to use higher shutter speeds (thinking that my subject will be well focused, getting ride of hand movement effect). But somehow this is not the case.

    Will a camera, in this case 20D, have a focus calibration problem? I really hope not...
    do the focustest chart test lor

    and also... f/1.8 may not produce the sharpest image... usually got to stop down a bit depending on lense lor....

    try f/2.0 2.4 2.8 3.2 alllll the way until f/4 or f/8 and compare on your monitor

  7. #27

    Default Re: Sharp photos - How to Shoot ah?

    Thanks to one and all for your valuable feedback. I'll try to take some photos with a smaller aperture to see if I am able to get a much sharper photo.

    Hi Slooow, is there a focus test chart available in the market, or can I just simply download it from the web. Kinda new to photography, but I am learning (thanks to you guys). =)

    My autofocus is set to centre (default). When I take a photo, I will point that centre focus point on the subject, half press the shuttle release, move the camera away from the subject to place it at 1/3 of the screen (with my finger still half press on the shuttle release button) and then snap the photo. Is this the correct method?

    I'll try to snap some photos and attach them here tomorrow.
    Last edited by skyhifi; 4th September 2006 at 01:17 AM.

  8. #28
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    Default Re: Sharp photos - How to Shoot ah?

    http://www.canon.com/camera-museum/c...8_usm_dof.html

    The 85mm at 1.8, 1 m away, has a DOF of FD - ND = 1.01m - 0.99m = 2cm
    2cm of acceptable focus sharpness. Meaning, in actual fact, if you were to pixel peep, you'd have less than 1cm of sharp image.

    Presuming a standard size head of 20cm, you'll need F5.6 at 2m away to be able to capture the eyes + shoulder in relative sharp focus.

  9. #29
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    Default Re: Sharp photos - How to Shoot ah?

    LOL right, i forgot to reply the question.. as student mentioned, it's best to shoot the instant you got your focus.

    IF you were to shift your camera after achieving focus... there's a chance you'll move out of the focal region. Are you confident that your range of motion is only 2 dimentions, along the XY plane (up and down only)? that you don't sway forward or back even 1cm?

  10. #30

    Default Re: Sharp photos - How to Shoot ah?

    Quote Originally Posted by student
    ...... With a system like what you have, you are relying on the camera's autofocussing mechanism which, unless faulty, is very accurate. But once focus is locked, do not delay, because if you or the subject move, you might have an out of focus image. WIth my manual camera, even if I delay, it matters not, because I do not assume focus is right, and there is no autofocus to trick me.
    Agree with Doc.

    From my own experience with the EOS 1Ds MkII, Canon's auto-focus system is indeed a bit tricky. Once you 'lock-in' your subject, do not hesitate or move, click the shutter at once (follow the sniper's code '1 shot, 1 kill'). Otherwise, your images will not be sharp. This is especially true with Image Stabilizer lenses. The respond is in terms of miliseconds,

    To overcome this problem, I do manual focusing (yes, back to stone age). Your results are, however, reassured especially shooting at f1.8, where the depth of field is just a matter of inches.
    Last edited by photobum; 4th September 2006 at 07:24 AM.

  11. #31

    Default Re: Sharp photos - How to Shoot ah?

    well if your subject is not within the range of the centre AF point, you can always select the other points.
    random equipment.
    where are my primes?

  12. #32
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    Default Re: Sharp photos - How to Shoot ah?

    Check the MTF for this lens here:

    http://www.photozone.de/8Reviews/len...0_18/index.htm.

    The pic from max aparture with Canon & Nikon are normally not delivered with promise.

  13. #33

    Default Re: Sharp photos - How to Shoot ah?

    its a bit vauge to post questions about sharpness, without posting an example.

    sure, at 1.8 your DOF is going to be thin, but it doesnt mean you cant get a tack sharp picture...

  14. #34

    Default Re: Sharp photos - How to Shoot ah?

    Quote Originally Posted by jdredd
    its a bit vauge to post questions about sharpness, without posting an example.

    sure, at 1.8 your DOF is going to be thin, but it doesnt mean you cant get a tack sharp picture...
    Agreed. It depends on the situation as well but you should always try to stop down without losing the bokeh for that clear skin tone if your shuttle speed permits

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