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Thread: I can't get a sharp picture for the life of me!

  1. #21
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    Re: I can't get a sharp picture for the life of me!



    Quote Originally Posted by jlau


    If that jerk would come see me I just might try out his lens...but...lets not get into that.


    Sorry, couldn't resist making a comment...I just want to point out that lucky is the man who has a significant other with whom he shares an interest in photography. Very, very lucky.


    Can you try posting a test chart? It doesn't have to be elaborate. Just take a photo of a calendar hanging on the wall, something where you can confirm focus on a flat target. Taking photos of three-dimensional objects can be misleading due to shallow DOF.

  2. #22

    Re: I can't get a sharp picture for the life of me!



    You try telling him that! Ugh. a wijajlkd awjds lkjsjlkdalsd.





    Anyways, here is a...ugh...my attempt at a test chart.


    http://img25.imageshack.us/img25/7687/sdfsdfuu.jpg

  3. #23
    Senior Member jks_photo's Avatar
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    Re: I can't get a sharp picture for the life of me!



    hi,


    have you ever tried setting to your focus point on the camera?? try to set set you camera to always focus using the center focus point. that way you'll be sure that your camera will focus only on the subject where the center focus point is on. You may may have set it at automatic whereby the camera chooses where to focus. so though it gives you the green light saying its focused, it may have actually focused on a different part of the whole image and not necessarily on what you are focusing at. Try to check this out. The red blinking lights you see when you look into your veiwfinder, the one in the center should always be "the only one" blinking when you half press the shutter and the camera starts to focus.


    This doesn't mean that your subject has to be in the center of the shot all the time. You can always focus on the subject first [half press the shutter] then without releasing the half press on the shutter recompose the shot so that the subject is on one side of the shot if that's what you want. What you can be certain of is that the subject will be in focus and judging by the camera and lens you use you should have no problem getting sharp images.

  4. #24

    Re: I can't get a sharp picture for the life of me!



    I am not sure what you mean by focus point? I have tried all metering options on the camera including, evaluative, partial, spot, and centerweighted average...I am assuming that the AF points that I see through my viewfinder are what the camera is focusing on right? Objects are not moving, and the only movement I'm contributing may or may not be my hands so I am not sure...where I am going with this anymore...but...yes...

  5. #25
    Senior Member jks_photo's Avatar
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    Re: I can't get a sharp picture for the life of me!



    hi


    yes they are called AF points. sorry for the wrong terminology.


    yes,try to set your camera so it ONLY uses the center AF point. thats the one in the center of your viewfinder.

  6. #26
    Senior Member jks_photo's Avatar
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    Re: I can't get a sharp picture for the life of me!



    the metering options on the camera only controls how the camera meters or calculates the "right" exposure. It doesn't really have much to do [at least for me] with the sharpness of the picture.


    I would suggest shooting in the AV mode. That way you control the depth of field which determines which part of the image is sharp which is "out-of-focus" with your 2.8 lens this will be easy. But to get sharpest image try not to use openings higher than f4. so 5.6, 8, 11 all will give you sharp images.


    by the way also try to adjust the sharpness control on the picture style you currently use this will also help.

  7. #27
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    Re: I can't get a sharp picture for the life of me!



    Well, you could post his email address on here and watch dozens of photographers write him messages saying what a dork he's being. (Kidding, of course) [:P][]


    As for your test chart, it's a good start. Here are a few comments:
    1. Sorry for not telling you earlier, but when you shoot the test target, make sure you force the camera to focus using only the center AF point. This is not a huge issue, for reasons I will explain later.
    2. Post two 100% crops from each shot. The first crop should be from the center, and the second crop should be any of the corners. If your test target is not large enough to fill the entire frame, a simple solution would be to take another object (like a piece of paper with printing on it) and stick it on the wall in the spot where it'll show up in a corner of the photo. These two crops help us determine whether your lens is faulty, but even better would be to compare the performance from corner to corner, because if the lens is misaligned, you could have one half of the image sharper than the other!
    3. From what I can see from your test images, the performance @ 55mm is not as good as @ 20mm. I realize you were shooting in available light so you were going to ISO 1600, but try finding a nice bright lamp to shine on your target so you can hopefully shoot at ISO 100-200. This will enable us to see just how much detail can be resolved by the sensor+lens combo.
    4. Note that if the lens is not up to spec, the solution is simply recalibration by Canon. Judging from the 100% crop of the image, I would say your camera's sensor is capable of resolving enough fine detail @ ISO 1600, and that it is the lens that does look a little soft @ 20mm and more so @ 55mm.
    5. Shooting this test is very, very informal. It's not going to show you subtle defects, only major ones. But that is the goal, to diagnose major problems.



    It's hard to say for sure whether the lens is not up to spec. If you can test out the EF 24-105/4L IS, that would be an excellent next step. And if you aren't satisfied with the EF-S 17-55/2.8 I would not hesitate to send it to Canon to have it looked at. Good luck!

  8. #28

    Re: I can't get a sharp picture for the life of me!



    Lol thank you for putting a smile on my face. Anyways...


    So I've tested my lens in daylight (FINALLY) and I'm too lazy to post my results but it is indeed sharp with enough light out even AT 2.8. Not so much when about 1-1.5m away from the subject though (no zoom). Is that normal? Also, is it normal that I cannot get a sharp image at 2.8 in LOW light?


    Oh and just wanted to thank everyone who's helped me so far =)

  9. #29

    Re: I can't get a sharp picture for the life of me!



    So I changed the focus to only focusing on the centre of the frame. I THINK its helped, but I was shooting in daylight today so I will test this out tonight.


    I have found that indeed f/4 range is sharper, but the point if my getting this lens is that I can use it in low light with aperture wide open. Otherwise...what was the point of getting a 2.8 if it can't give me a sharp image?


    Where is this sharpness control...??

  10. #30
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    Re: I can't get a sharp picture for the life of me!



    Having a lens at f/2.8 will not garantee sharp images, it allows the user to shoot images in lower light without a tripod (better if IS is available for further step-downs). A lens @ f/2.8 allows more light into the lens/camera. You can try taking a photo at f/2.8 and check the aperature within the viewfinder, then change it to f/4 and so on. With each step down, you will notice the aperature time increases. Whereas at f/2.8 you may get 1/13 of a sec, at f/4 you may get 3 seconds. But withf/4 and lower, you will get some really beautiful background blur and a narrower depth of field!


    Hope this helps.
    Canon 450D Gripped, Canon 24-105 f/4L, Canon 70-200 f/2.8L IS USM II, Sigma 10-20 EX f/4-5.6, Canon S95

    “There are always two people in every picture: the photographer and the viewer.” -Ansel Adams

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