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Thread: Canon 550d, 18-135 lens and focus problem/s?

  1. #1
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    Canon 550d, 18-135 lens and focus problem/s?

    I know it is my fault for not adjusting the F-Stop before I took the images, but it has maybe highlighted another (possible) problem:

    I had the F at 5.7 and zoomed in on things with Auto Focus set.

    After a few shots I realised the error and set F 8.

    It beeped (center spot only used) and I clicked.

    Alas when I got home and looked at the early pictures, they were BLURRY.

    Later on, I was mucking about and tried the situation again.

    Greg? (Geoff? Hey I am BAD with names. B A D !) showed me the trick with live view and zooming in....

    Anyway.

    My question/concern:

    If I have a solitary subject and F 5.7 (or 4.5....) and it is a LONG WAY AWAY. I auto focus on it (beep) and click.

    It should be in focus - shouldn't it.

    If I have F 8 it is, but obviously the DOF has something to do with it.

    So is there a problem with what is going on in the camera?

    I shall have to do more testing and see what happens.

    Shall post results when I have them.
    +===========================================+
    Canon EOS 550D 18-135 (IS) lens 90-300 lens
    +===========================================+

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    I think the results may help but we are missing some information.

    What was the shutter speed? The camera can achieve focus but it may well have chosen a slow shutter speed and that could be causing camera shake resulting in blur. Are ALL you images blurred or some / most/ 1 in 10?

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    Administrator ricktas's Avatar
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    Auto Focus works at the widest aperture, so what ever f stop you choose should have zero affect on focus. What happens is the lens opens up to the widest it can (prob f3.5) for the lens you used, and then focuses, then the lens closes back down to f8 or whatever aperture you have selected to take the shot. So aperture should have zero affect on focusing correctly.

    Post some photos with EXIF in-tact and let us take a look. The problem is probably behind the camera, not in it (photographer error). And letting us see the photos with EXIF will allow us to assist re settings etc.
    Last edited by ricktas; 20-12-2013 at 6:30am.
    "It is one thing to make a picture of what a person looks like, it is another thing to make a portrait of who they are" - Paul Caponigro

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    Here is some examples:

    I am not that good with EXIF data and if it is stored, so here it is anyway.
    I feel it is better to have too much than me posting some and not including what is needed and getting people asking me to include more information again and again.

    What I may do later on today if I feel so inclined is do another set and take MORE notes on what I am doing.
    Alas I am suffering severe blond moments these days.

    I took some pictures wide angle and two aperture settings.
    One 5.7-ish and the other at the other end.

    I let it "auto focus" then turned it to manual.
    Without adjusting it, I too the 5.7 then the 22.

    There is a change in what is in focus - obviously.
    But I only have the ONE spot for focusing. The center of the screen.

    The second two are what I was seeing on my computer with another two pictures zooming in to 101% and you can clearly see the difference.

    As I hadn't changed the focus and was focused on the bush (see red arrow/s) I'm concerned that there is something "wrong" with my setup.


    EXIF data for 5459:
    Make : Canon
    Model : Canon EOS 550D
    Orientation : Horizontal (normal)
    XResolution : 72
    YResolution : 72
    ResolutionUnit : inches
    ModifyDate : 2013:12:22 08:04:44
    Artist : Andrew Bruno
    WhitePoint : 0.313 0.329
    PrimaryChromaticities : 0.64 0.33 0.21 0.71 0.15 0.06
    YCbCrCoefficients : 0.299 0.587 0.114
    YCbCrPositioning : Co-sited
    Copyright :
    ExposureTime : 1/320
    FNumber : 5.6
    ExposureProgram : Aperture-priority AE
    ISO : 200
    ExifVersion : 0221
    DateTimeOriginal : 2013:12:22 08:04:44
    CreateDate : 2013:12:22 08:04:44
    ComponentsConfiguration : Y, Cb, Cr, -
    ShutterSpeedValue : 1/332
    ApertureValue : 5.7
    ExposureCompensation : -2/3
    MeteringMode : Multi-segment
    Flash : Off, Did not fire
    FocalLength : 135.0 mm
    UserComment :
    SubSecTime : 45
    SubSecTimeOriginal : 45
    SubSecTimeDigitized : 45
    FlashpixVersion : 0100
    ColorSpace : Uncalibrated
    ExifImageWidth : 5184
    ExifImageHeight : 3456
    InteropIndex : R03 - DCF option file (Adobe RGB)
    InteropVersion : 0100
    FocalPlaneXResolution : 5728.176796
    FocalPlaneYResolution : 5808.403361
    FocalPlaneResolutionUnit : inches
    CustomRendered : Normal
    ExposureMode : Auto
    WhiteBalance : Auto
    SceneCaptureType : Standard
    Gamma : 2.2
    Compression : JPEG (old-style)
    XResolution : 72
    YResolution : 72
    ResolutionUnit : inches
    ThumbnailOffset : 8892
    ThumbnailLength : 17876
    ---- MakerNotes ----
    MacroMode : Normal
    SelfTimer : Off
    Quality : Fine
    CanonFlashMode : Off
    ContinuousDrive : Single
    FocusMode : One-shot AF
    RecordMode : JPEG
    CanonImageSize : Large
    EasyMode : Manual
    DigitalZoom : None
    Contrast : Normal
    Saturation : Normal
    MeteringMode : Evaluative
    FocusRange : Not Known
    CanonExposureMode : Aperture-priority AE
    LensType : Canon EF-S 18-135mm f/3.5-5.6 IS
    LongFocal : 135 mm
    ShortFocal : 18 mm
    FocalUnits : 1/mm
    MaxAperture : 5.7
    MinAperture : 36
    FlashActivity : 0
    FlashBits : (none)
    ZoomSourceWidth : 0
    ZoomTargetWidth : 0
    ManualFlashOutput : n/a
    ColorTone : Normal
    FocalLength : 135 mm
    AutoISO : 100
    BaseISO : 200
    MeasuredEV : 11.75
    TargetAperture : 5.7
    TargetExposureTime : 1/323
    ExposureCompensation : -2/3
    WhiteBalance : Auto
    SlowShutter : None
    SequenceNumber : 0
    OpticalZoomCode : n/a
    CameraTemperature : 39 C
    FlashGuideNumber : 0
    FlashExposureComp : 0
    AutoExposureBracketing : Off
    AEBBracketValue : 0
    ControlMode : Camera Local Control
    FNumber : 5.7
    ExposureTime : 1/323
    MeasuredEV2 : 11.625
    BulbDuration : 0
    CameraType : EOS High-end
    NDFilter : n/a
    CanonImageType : Canon EOS 550D
    CanonFirmwareVersion : Firmware Version 1.0.9
    OwnerName :
    SerialNumber : 1032303043
    FNumber : 5.7
    ExposureTime : 1/332
    ISO : 200
    HighlightTonePriority : Off
    FlashMeteringMode : Off
    CameraTemperature : 39 C
    FocalLength : 135 mm
    CameraOrientation : Horizontal (normal)
    FocusDistanceUpper : inf
    FocusDistanceLower : 81.91 m
    WhiteBalance : Auto
    ColorTemperature : 5200
    PictureStyle : Standard
    LensType : Canon EF-S 18-135mm f/3.5-5.6 IS
    ShortFocal : 18 mm
    LongFocal : 135 mm
    FirmwareVersion : 1.0.9
    FileIndex : 5459
    DirectoryIndex : 100



    EXIF data for 5460:
    Make : Canon
    Model : Canon EOS 550D
    Orientation : Horizontal (normal)
    XResolution : 72
    YResolution : 72
    ResolutionUnit : inches
    ModifyDate : 2013:12:22 08:04:58
    Artist : Andrew Bruno
    WhitePoint : 0.313 0.329
    PrimaryChromaticities : 0.64 0.33 0.21 0.71 0.15 0.06
    YCbCrCoefficients : 0.299 0.587 0.114
    YCbCrPositioning : Co-sited
    Copyright :
    ExposureTime : 1/20
    FNumber : 22.0
    ExposureProgram : Aperture-priority AE
    ISO : 200
    ExifVersion : 0221
    DateTimeOriginal : 2013:12:22 08:04:58
    CreateDate : 2013:12:22 08:04:58
    ComponentsConfiguration : Y, Cb, Cr, -
    ShutterSpeedValue : 1/21
    ApertureValue : 22.6
    ExposureCompensation : -2/3
    MeteringMode : Multi-segment
    Flash : Off, Did not fire
    FocalLength : 135.0 mm
    UserComment :
    SubSecTime : 68
    SubSecTimeOriginal : 68
    SubSecTimeDigitized : 68
    FlashpixVersion : 0100
    ColorSpace : Uncalibrated
    ExifImageWidth : 5184
    ExifImageHeight : 3456
    InteropIndex : R03 - DCF option file (Adobe RGB)
    InteropVersion : 0100
    FocalPlaneXResolution : 5728.176796
    FocalPlaneYResolution : 5808.403361
    FocalPlaneResolutionUnit : inches
    CustomRendered : Normal
    ExposureMode : Auto
    WhiteBalance : Auto
    SceneCaptureType : Standard
    Gamma : 2.2
    Compression : JPEG (old-style)
    XResolution : 72
    YResolution : 72
    ResolutionUnit : inches
    ThumbnailOffset : 8892
    ThumbnailLength : 18348
    ---- MakerNotes ----
    MacroMode : Normal
    SelfTimer : Off
    Quality : Fine
    CanonFlashMode : Off
    ContinuousDrive : Single
    FocusMode : Manual Focus (3)
    RecordMode : JPEG
    CanonImageSize : Large
    EasyMode : Manual
    DigitalZoom : None
    Contrast : Normal
    Saturation : Normal
    MeteringMode : Evaluative
    FocusRange : Not Known
    CanonExposureMode : Aperture-priority AE
    LensType : Canon EF-S 18-135mm f/3.5-5.6 IS
    LongFocal : 135 mm
    ShortFocal : 18 mm
    FocalUnits : 1/mm
    MaxAperture : 5.7
    MinAperture : 36
    FlashActivity : 0
    FlashBits : (none)
    ZoomSourceWidth : 0
    ZoomTargetWidth : 0
    ManualFlashOutput : n/a
    ColorTone : Normal
    FocalLength : 135 mm
    AutoISO : 100
    BaseISO : 200
    MeasuredEV : 11.75
    TargetAperture : 23
    TargetExposureTime : 1/20
    ExposureCompensation : -2/3
    WhiteBalance : Auto
    SlowShutter : None
    SequenceNumber : 0
    OpticalZoomCode : n/a
    CameraTemperature : 39 C
    FlashGuideNumber : 0
    FlashExposureComp : 0
    AutoExposureBracketing : Off
    AEBBracketValue : 0
    ControlMode : Camera Local Control
    FNumber : 23
    ExposureTime : 1/20
    MeasuredEV2 : 11.625
    BulbDuration : 0
    CameraType : EOS High-end
    NDFilter : n/a
    CanonImageType : Canon EOS 550D
    CanonFirmwareVersion : Firmware Version 1.0.9
    OwnerName :
    SerialNumber : 1032303043
    FNumber : 23
    ExposureTime : 1/21
    ISO : 200
    HighlightTonePriority : Off
    FlashMeteringMode : Off
    CameraTemperature : 39 C
    FocalLength : 135 mm
    CameraOrientation : Horizontal (normal)
    FocusDistanceUpper : inf
    FocusDistanceLower : 81.91 m
    WhiteBalance : Auto
    ColorTemperature : 5200
    PictureStyle : Standard
    LensType : Canon EF-S 18-135mm f/3.5-5.6 IS
    ShortFocal : 18 mm
    LongFocal : 135 mm
    FirmwareVersion : 1.0.9
    FileIndex : 5460
    DirectoryIndex : 100
    Attached Images Attached Images

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    Looks like you didn't go to f8, but to F22 @ 1/20th sec. There's your problem. Camera shake and blurry photo.

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    Administrator ricktas's Avatar
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    Yep, agree with. f22 and thus slow shutter speed and blurry due to camera shake during 1/20th second exposure

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    (Egg on my face)

    I used a tripod. Probably should have said that.

    As I was wanting to take a few shots and reduce external variables, I took my tripod.

    Sorry.

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    A royal pain in the bum! arthurking83's Avatar
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    Quote Originally Posted by Mr Felix View Post
    ....

    I used a tripod. Probably should have said that.

    .... .

    It must be noted that the use is of a tripod can be of no consequence in attempting to capture sharp images, if you're using it incorrectly too.
    Did you use a remote release?, did you have IS on .. etc.
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    Quote Originally Posted by arthurking83 View Post
    It must be noted that the use is of a tripod can be of no consequence in attempting to capture sharp images, if you're using it incorrectly too.
    Did you use a remote release?, did you have IS on .. etc.
    Interesting.

    Granted I put up 4 pictures but only 2 sets of EXIF data. The second two were illustrations on how when I zoom in digitally on my computer there is blurring.

    I took two pictures ZOOMED IN, and two picture WIDE ANGLE, as I don't remember if the pictures were wide or zoom when I originally noticed the blurring.

    My ORIGINAL question / concern was that when I was at the recent meeting, I took some pictures with F5.7 and the pictures were blurry. The subjects were well lit, and I had Auto Focus on. (No stabilisation).

    I am concerned that at F5.7 (which means a lot of light is getting in) the camera is somehow not focusing correctly, although it does beep saying it is in focus.

    I took some example pictures and posted them for CLARIFICATION rather than being obfuscated to the point of frustration.

    So let's re-cap:

    The two first pictures:
    5459 and 5460 as their names are.
    5459 is a BLURRED picture. 5460 is a SHARP picture.
    5459 has an F stop of 5.7 and 5460 has an F stop of 22.


    IF (and I stress IF) the camera was shaken with F22 because I didn't use the tripod correctly (and / or cable release) why is that picture so much clearer than the other one which had an aperture of 5.7?

    Your whole post is kind of "back to front" with the results I have posted.

    The F5.7 which has a faster shutter speed - because there is more light getting through the hole - is BLURRED where as the one which has an F of 22 and a slow shutter speed is clearer.


    Did I miss something?

    Am I wrong is asking why with I have SHALLOW depth of field, the subject is (somewhat obviously) out of focus where as when I have a DEEP depth of field the subject is in focus.

    Now granted I went from 1 extreme to another with 5.7 to 22, but even so: Why is the picture blurred when I let the camera AUTO FOCUS on the subject; turn off auto focus; take a picture at F 5.7 then change it to F22 and get a clear picture.
    Last edited by Mr Felix; 22-12-2013 at 5:12pm.

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    Dude - chill.

    I refrained from posting a response to this tread for a number of reasons but now I feel your frustration and think i might have something valuable to add. I am going to reply in bullet point, it is more direct and although it risks being inflamatory it is not intended to be, direct comments in bullet form tend to seem sharp. (no pun intended)

    • Looking at the images I see no problems.
    • Image 1 looks fine given the focus is the bush. Out of focus areas are due to DOF.
    • Image 2 looks fine given the focus is the bush. Out of focus areas are due to camera shake.
    • You took an image at 300mm, F22 and 1/20 of a second. If you fart it will blur. - Rick's comments are valid.
    • Images 3 and 4 look nice with the red lines but since the exif does not apply to them I cannot see the relevance.
    • Images 3 and 4 look out of focus. I hope the red lines did not affect the camera but if they did consider not taking photos with the red lines in place.
    • You may have a broken camera. You may be getting something wrong. You are on an internet forum asking for advice - advice will be given, even if you do not like that advice.


    In my honest opinion it is too hard to tell what is going on given the images posted. It certainly looks like user error but hell you might just have a duff camera. Maybe there is someone on the forum that lives close enough to you for you to arrange a meet and see if they experience the same issue.

    Hope that was clear and not too obfuscated.

    Cheers

  11. #11
    In Training MarkChap's Avatar
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    I know the question has been asked before, but the quality of the tripod will have a lot to do with whether your images are sharp or not also

    And I really hate to say this, but those results are probably as good as can be expected from that lens
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    A royal pain in the bum! arthurking83's Avatar
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    Yeah, and the way the question has been posted is a bit convoluted too.

    Posting images and exif separately makes the assessment of any errors/problems harder than it needs be.

    Firstly just post the images to the forum, with all exif intact WITHIN the image itself .. not a a separate post/paragraph.

    We can see the exif within the image.

    Secondly, are you sure that the exif is definitely for the images you described. ie. have you accidentally uploaded the images in reverse order?
    This is why it's better to just upload the images .. with exif intact, as the possibility of confusion is eliminated.

    What worries me about the probable roundabout nature of this thread is that you have posted the images 5460 and 5459 in the reverse order that you posted the exif data!

    BUT!! .. if you are indeed definitely positively 100% certain that the images are 5460 at top and 5459 second, then one thing is clear ... you need a better tripod!

    Focus doesn't look to be an issue with that image. It's almost certainly a blur issue(camera shake) of some kind.

    Things that can conspire against you that result in camera shake, can be something as simple as the combination of IS on and a highish shutter speed.

    One major clue as to why focusing doesn't appear to be a problem in the blurred image is that even if the camera misfocused in that image, it wouldn't have misfocused to the point where it set the lens to a very close focused distance. It may have misfocused along the plane for example at the far distant trees, or the silver Camry .. as opposed to the bushes behind it.
    But if it did focus at those two distant points, the natural DOF would still render the image with some detail.
    Only if you focus really close .. say 3m or so .. will the background blur so much.

    I'd say a combination of a possibly soft lens at wide open aperture and long focal length, and camera shake have created the blurry image.

    But it can't be expressed strongly enough .. leave exif intact and embedded in the image, if you want a reasonably speedy reply to your problem.

    if your current software can't do this for you, there are many other freebies that can.


    Now, as for an easy way to check for focusing issues with your camera/lens:

    1. take camera to similar spot and leave aperture wide open, and focal length as previously done.
    2. focus as per the normal method, but be sure not to take an exposure(yet).
    3. turn on live view(I'm pretty sure the 550D has Lv mode) touching nothing else.
    4. Is the image through Lv mode looking sharp(enough)?
    5. turn focus collar a bit this way and that way to see if you can achieve a more acute image detail rendering on the review screen.

    Things that you need to be 100% sure of if trying this.
    Make sure the camera doesn't automatically try to focus on it's own accord when in Lv mode.
    Make sure you don't press the focusing mechanism again during any of the steps above.

    Now take a few exposures too:
    one at f/wide open, and one at f/8.

    As already said .. the camera always focuses with the lens wide open irrespective of aperture set. They all do this except for a very few exception(lenses!) but I can't see any of these lens types listed in your signature.

    So, by deduction, your camera must be focusing OK, if it's has captured the f/22 image sharply, as the aperture used to focus was f/wide open anyhow.
    If the image at f/22 is sharper than at say f/5.6, then this is a consequence of a hazy lens rendering at wide open aperture .. not uncommon.

  13. #13
    Administrator ricktas's Avatar
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    pressing the shutter button and or mirror slap can invoke movement in a camera, even if on a tripod, and that is more evident at shutter speeds like 1/20th second etc.

    I feel that the cause is definitely camera shake at the time of exposure, and nothing else. A tripod does not in itself ensure a camera is held perfectly still during exposure. There are many factors that can cause blur whilst using a tripod.

    * wind
    * wet Sand (sinking into the sand)
    * pressing the shutter button
    * touching the camera or tripod
    * mirror slap (as the mirror flips up it hits the mirror box and that hit causes slight movement
    * passing traffic, especially trucks/ buses etc

    and more.

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    In Training MarkChap's Avatar
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    You refer to image numbers 5459 and 5460, but the image numbers in the screen grabs are 5456 and 5457, ?

    Are you sure you have the correct images ??

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    Ok folks update:

    (Oh Rick, I don't seem to be getting notifications any more)

    The last couple of days have been a bit yuck, so any testing has been held off.

    Today (27'th) is warm and sunny. (Humid as well.)

    I went to a park and set myself up.

    The subject was about 40 metres away.

    51 photos.

    17 wide angle "auto focus" 17 wide angle my focus. Alas as it was bright I couldn't verify the altered focus was "better" but to make a comparison.

    Then 17 fully zoomed pictures with auto focus.

    Now, let's clarify what I mean:
    "Auto focus" - I set the lens to AUTO FOCUS, acquire the subject the turn the lens to MANUAL.
    After that I do NOT adjust the focus at all. I ONLY adjust the F number.

    Starting at widest angle and F3.5 I took a photo.
    Then worked my way up to F22.

    I was using a Manfrotto tripod and didn't bother with cable release.
    Why?
    Well, because at the "sunset" meeting in Balmain, when I took some pictures of buildings which were well lit (WELL LIT) I have F5.7 and they were blurred. When I went to F11 it was ok. Which got me to wondering why with a shallow depth of field and AUTO FOCUS (on stationary objects) I was getting blurs.

    51 pictures is a lot to upload and I don't want to bore you all with them all.

    But I did notice some weird things:

    F3.5 with a subject at 40 metres..... Shouldn't have much DOF - right?
    Looks like everything is in focus.

    Or: Suffice to say close up isn't BLURRY!

    As the F number increases there isn't any discernible increase in the DOF. Hmmmmm..

    I know I am getting old, but this doesn't make sense to me.

    When I zoom in - digitally - the subject is YUCK! Blurred like crazy.

    Yes, there could be a thing about digital zoom, and how it does it, etc etc etc.

    Granted. I'm no expert. I can only report on what I see.

    What I may do soon is go through and reduce the 17 of each down to maybe 3. First, middle and last, and post them. Though that will be nine.

    We can work on it from there.

    Oh, other things:

    When I zoomed all the way in - with the lens - and took pictures:
    This changed the whole thing as I said: The subject was in focus but the whole frame changed.
    Now I had more "background" things - or things BEHIND the subject - in view.

    Looking at them, the things behind hardly changed with the change in DOF either.

    So what is going on I wonder?

    Could it be that in WIDE: The lens is just focusing on "what ever" and not really worrying? Where as when I zoom in and the subject is "there" it knows on what to focus?

    As the lens doesn't have distance markers it is frustrating for me to workout where it is focused. Sure I can turn the dial and see what goes on. But it doesn't tell me if I am focusing "in" or "out".

    Yeah, find something in the mid ground and work it out. I kinda worked this out now.

    Need more time to get more data.

    Anyway, that's the situation to date.

    Be back soon.

    - - - Updated - - -

    OK, here they are...

    The 9 pictures.

    Again I shall state that I am looking for "out of focus" with using small DOF, as opposed to the subject being in focus with large DOF.

    The "Subject" is the bin on the post in the distance.

    You can see when I took them: Early morning. Sun was to my left and behind me.

    I ran a line to the subject to mark 10 metre marks. Shown by the skewers in the ground.
    Sorry I didn't really have anything better. I was hoping for witch's hats, but I couldn't catch any.

    01 3.5 18.0 mm auto focus (Large).JPG01 3.5 18.0 mm manual focus (Large).JPG01 5.6 135.0 mm autol focus (Large).JPG09 9.0 18.0 mm auto focus (Large).JPG09 9.0 18.0 mm manual focus (Large).JPG

  16. #16
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    This is it.

    The last ones.

    Look at the names. They show a number (1-17) for me so I know which is which. The F number lens/focal length and auto/manual focus.

    That is a BIT misleading but for the sake of me and knowing which ones the camera focused, and which ones I did, I had to call them something.

    Alas the "manual focus" ones seem to be a waste of time.

    I may have to do it again at 135mm and see what happens.

  17. #17
    Administrator ricktas's Avatar
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    Ok

    to answer one of your questions/comments

    F3.5 with a subject at 40 metres..... Shouldn't have much DOF - right?
    Looks like everything is in focus.
    Depth of field is NOT just f-stop based, but the other BIG factor is distance to subject

    @ f3.5 with a distance to subject of 40 metres using a 50mm lens (as an example) hyperfocal distance is around 25 metres and acceptable sharpness will start around 15 metres from lens, with infinity (as far as you can see) being the other end of the sharpness point

    Now to show you how this changes with distance, lets say the same as the above but your distance to subject is 2 metres, and nothing else changes. sharpness will occur between 1.8metres from lens out to about 2.1 metres and then sharpness will drop off for anything further away that that. F-stop and depth of field is MAJORLY affected by distance to subject. The further your subject is away from the lens the more will be in focus when you have focused on your subject. You seem to have forgotten/not know the distance to subject implications of f-stops and focus points.

  18. #18
    A royal pain in the bum! arthurking83's Avatar
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    Quote Originally Posted by Mr Felix View Post
    .......

    But I did notice some weird things:

    F3.5 with a subject at 40 metres..... Shouldn't have much DOF - right?
    Looks like everything is in focus.

    Or: Suffice to say close up isn't BLURRY!

    As the F number increases there isn't any discernible increase in the DOF. Hmmmmm..

    I know I am getting old, but this doesn't make sense to me .........
    OK, so from the results you now see, you SHOULD have learned something ... and Rick summed it up perfectly!

    Also to note.
    If you stop down a bit, you may in fact see some sharpening up of the image even tho the DOF really doesn't change all that much.
    This is simply because the lens may render more sharply as you approach some of it's optimum settings.

    Your comment that the manually focused images were a waste of time needs qualification!
    Why were they a waste of time. Did they not work out at all .... did the resultant images look identical to the AF images

    Manually focused images for testing are never a waste of time!
    If you see no difference between manually(and optimally) focused images and the automatically focused images, the only conclusion is that the AF system is operating correctly.
    If the manual images came out looking somehow worse than the other images, it could yet again be operator error induced.

    Take care, don't rush and you really don't need such volumes of images to confirm basics such as AF operation.

    And learn to upload images in sequences that help your thread to mean something.

    That is:
    if you are showing examples of images shot at 135mm, post the 135mm images in sequence.
    If you want to display any images for determining wide angle, eg. 18mm .. issues, post the 18mm shots in sequence.

    Scrolling up and then down and then up again to view images that are comparable to each other is not only annoying, but doesn't allow anyone to compare the images in a meaningful way .... unless we download them to our PC's.


    And finally you said this:

    .... at the "sunset" meeting in Balmain, when I took some pictures of buildings which were well lit (WELL LIT) I have F5.7 and they were blurred. When I went to F11 it was ok....



    Post the images.
    Something that should be understood about how light works.
    If light is harsh, a lens set to wide open aperture value can render the images with low contrast and flare. That is, the fact that the lens is set wide open doesn't allow the lens to render the image optimally.
    Stopping the lens down sufficiently can help to increase contrast.
    Without being there .. without knowing the conditions at the time of the shoot ... without seeing images .. it's impossible to define the why's and wherefore's of what you are seeing.
    And .. to put it simply .. there are times when your AF system simply mucks it all up, and it misses focus.

  19. #19
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    Hi guys.

    Rick:
    I shall mention again: I didn't get e-mails telling me of these two replies. I just happened to come in and look.


    Arthur:
    Uplaoding - the file names are sequential. Sorry I uploaded them in a way I thought at the time was good.
    What I have noticed is that sometimes the order I put them and the order they "arrive" on the site is DIFFERENT!
    Shall try in the future to do it as you suggested.

    The pictures I mentioned about the building being out of focus.
    Yeah, well I don't have "out of focus" and "in focus" pictures of the same thing to compare.

    I (stupidly) took the camera out and took some pictures not noticing the F5.7.
    After taking a few, I just happened to look at the screen and noticed the blurriness.
    This prompted me to try F8/9.
    Subsequent pictures were ok.

    I mentioned it to "Greg" (?) and was looking at the city. He suggested going to live view, zooming in, and manually focusing.

    I did that, half pressed the button, saw the image. Switched to manual and adjusted.

    Strangely the image became clearer.

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