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Thread: How does a scratch on Low Pass Filter looks like?

  1. #1

    Default How does a scratch on Low Pass Filter looks like?

    Hi guys,

    I recently tried to clean my sensor myself as i noticed some faint dust specks on my pictures. I did some self-diagnose - taking photo of a white screen, and then blah blah (not gonna type the entire thing) - when the supposely clean sensor actually is FULL of dust.

    I googled on the how-to and gladly followed it faithfully, except when someone bumped onto my elbow while i was dedicately using cotton buds to rub off some subborn dust - i know what im doing, just read on.

    Since then there is this really bright spot appearing at the same place everytime on my pictures. Did i just busted my low-pass filter?
    Rig: Trusty (dusty) 6 years old Sony A350, Sony 16-105 lens, Sony Flash unit
    Nokia Lumia 1020

  2. #2
    Moderator daredevil123's Avatar
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    Default Re: How does a scratch on Low Pass Filter looks like?

    Quote Originally Posted by AlphaLuver View Post
    Hi guys,

    I recently tried to clean my sensor myself as i noticed some faint dust specks on my pictures. I did some self-diagnose - taking photo of a white screen, and then blah blah (not gonna type the entire thing) - when the supposely clean sensor actually is FULL of dust.

    I googled on the how-to and gladly followed it faithfully, except when someone bumped onto my elbow while i was dedicately using cotton buds to rub off some subborn dust - i know what im doing, just read on.

    Since then there is this really bright spot appearing at the same place everytime on my pictures. Did i just busted my low-pass filter?
    Can you post a sample pic with that bright spot here?

  3. #3

    Default Re: How does a scratch on Low Pass Filter looks like?

    remove lens from body, cover body with body cap.
    go to a dark enclosed room,
    select manual cleaning so mirror will flip up [ do "not" remove body cap at this moment ]
    wait for 5 mins while mirror is flipped up and cmos exposed [ all while body cap is covering it ]
    switch camera to off. [ mirror will flip down ]

    try again to mount lens and take a few test shots to see if bright spot still there..

  4. #4
    Deregistered allenleonhart's Avatar
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    Default Re: How does a scratch on Low Pass Filter looks like?

    Quote Originally Posted by farbird View Post
    remove lens from body, cover body with body cap.
    go to a dark enclosed room,
    select manual cleaning so mirror will flip up [ do "not" remove body cap at this moment ]
    wait for 5 mins while mirror is flipped up and cmos exposed [ all while body cap is covering it ]
    switch camera to off. [ mirror will flip down ]

    try again to mount lens and take a few test shots to see if bright spot still there..
    eh if you are already having body cap on... why the need to go to a dark enclosed room?

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  6. #6
    Senior Member edutilos-'s Avatar
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    Default Re: How does a scratch on Low Pass Filter looks like?

    It sounds like a bright pixel.

    Nothing to do with the cleaning, but I'm not sure how you use the "cotton buds" to clean your sensor. I do so, but only for wet cleaning. I won't go out of my way to touch the sensor unnecessarily too.

  7. #7
    Senior Member edutilos-'s Avatar
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    Default Re: How does a scratch on Low Pass Filter looks like?

    Quote Originally Posted by farbird View Post
    remove lens from body, cover body with body cap.
    go to a dark enclosed room,
    select manual cleaning so mirror will flip up [ do "not" remove body cap at this moment ]
    wait for 5 mins while mirror is flipped up and cmos exposed [ all while body cap is covering it ]
    switch camera to off. [ mirror will flip down ]

    try again to mount lens and take a few test shots to see if bright spot still there..
    So what is this supposed to solve??

  8. #8

    Default

    I also unable to explain. Only know that I experienced this once and managed to resolve it.

  9. #9
    Member Hanmin147's Avatar
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    Default

    Quote Originally Posted by farbird
    remove lens from body, cover body with body cap.
    go to a dark enclosed room,
    select manual cleaning so mirror will flip up [ do "not" remove body cap at this moment ]
    wait for 5 mins while mirror is flipped up and cmos exposed [ all while body cap is covering it ]
    switch camera to off. [ mirror will flip down ]

    try again to mount lens and take a few test shots to see if bright spot still there..
    Hey, I tried what you suggested but it doesn't work! Do I have to go to a dark room because I didn't. Thanks!

  10. #10

    Default Re: How does a scratch on Low Pass Filter looks like?

    hi guys, i have to revive this thread that i started, because im facing with the same issue now.
    The reason i couldn't get back to the thread was because i couldn't get a sample photo as i sent my unit to Sony for their cleaning, which i forgot whether i paid - or was it free
    Plus, i didn't get notifications of replies to my email by default.

    Thanks for the warmth response.
    ---------------------------------------------------------------------------------------------------------------
    I tried to clean just now with a sensor brush from Lenspen + hand blower FOC when i bought this unit.
    Now after repeated attempts not only did the dust merely shifted locations but when i tried to take photo against my white wall at F36 inf focus lots of white specks appeared.

    My tests to determine location of dust was done on white photoshop monitor, 2 photos are attached before and after. The photo of my white wall with the white specks are attached as well.
    https://docs.google.com/file/d/0B2zV...it?usp=sharing
    https://docs.google.com/file/d/0B2zV...it?usp=sharing
    https://docs.google.com/file/d/0B2zV...it?usp=sharing

    Seriously did i do anything wrong with my brushing? How come my unit gets dust on sensor so frequently?
    Last edited by AlphaLuver; 23rd September 2013 at 07:40 PM.
    Rig: Trusty (dusty) 6 years old Sony A350, Sony 16-105 lens, Sony Flash unit
    Nokia Lumia 1020

  11. #11
    Moderator catchlights's Avatar
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    Default Re: How does a scratch on Low Pass Filter looks like?

    Quote Originally Posted by farbird View Post
    Stray light from vf
    FYI, most cameras come with a small piece of plastic, calls "viewfinder cover", use it.
    anyway, just use anything to cover the viewfinder lar, even your hand also can right?
    Shoot to Live, Live to Shoot
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  12. #12
    Moderator catchlights's Avatar
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    Default Re: How does a scratch on Low Pass Filter looks like?

    FYI,

    dust spots will show up as darker dots.

    white spots usually are hot pixels, it show up when you doing long exposure, this is normal.

    white spots can be also dead pixel, it shows up at whatever exposure setting, this can be simply map out using software at your service center.



    from the photos you shown, if the white specks is taken with a long exposure, than that is perfectly normal.

    dust is everywhere, in the air you breathe, so it is perfectly common to have dust land on sensor, we just need to clean our sensor regularly, and we won't able to have 100% dust free sensor no matter how hard we tried, as long it won't show up in the images is acceptable, anyway, not every shot we will shoot on plain background with f32 right?


    you can try the Copperhill Sensor Cleaning kit, http://www.copperhillimages.com/shop...tion.php?id=71
    Shoot to Live, Live to Shoot
    www.benjaminloo.com | iStock portfolio

  13. #13

    Default Re: How does a scratch on Low Pass Filter looks like?

    Quote Originally Posted by catchlights View Post
    FYI,

    dust spots will show up as darker dots.

    white spots usually are hot pixels, it show up when you doing long exposure, this is normal.

    white spots can be also dead pixel, it shows up at whatever exposure setting, this can be simply map out using software at your service center.



    from the photos you shown, if the white specks is taken with a long exposure, than that is perfectly normal.

    dust is everywhere, in the air you breathe, so it is perfectly common to have dust land on sensor, we just need to clean our sensor regularly, and we won't able to have 100% dust free sensor no matter how hard we tried, as long it won't show up in the images is acceptable, anyway, not every shot we will shoot on plain background with f32 right?


    you can try the Copperhill Sensor Cleaning kit, http://www.copperhillimages.com/shop...tion.php?id=71
    awesome, thanks for the info.

    do you recommend me sending my unit to Sony for their cleaning, and if my sensor does really has dead pixels, remap?
    Rig: Trusty (dusty) 6 years old Sony A350, Sony 16-105 lens, Sony Flash unit
    Nokia Lumia 1020

  14. #14
    Moderator catchlights's Avatar
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    Default Re: How does a scratch on Low Pass Filter looks like?

    Quote Originally Posted by AlphaLuver View Post
    awesome, thanks for the info.

    do you recommend me sending my unit to Sony for their cleaning, and if my sensor does really has dead pixels, remap?
    if you find you are not competent to clean the sensor yourself, than bring it to Sony Service Center for sensor cleaning is a logical choice.

    as for suspecting dead pixels, tell the technician about it, let them take a look, see what they find and any recommendation.
    Shoot to Live, Live to Shoot
    www.benjaminloo.com | iStock portfolio

  15. #15

    Default

    Never clean your own sensor if you feel that you're not up to the task.

  16. #16

    Default Re: How does a scratch on Low Pass Filter looks like?

    Quote Originally Posted by catchlights View Post
    if you find you are not competent to clean the sensor yourself, than bring it to Sony Service Center for sensor cleaning is a logical choice.

    as for suspecting dead pixels, tell the technician about it, let them take a look, see what they find and any recommendation.
    Quote Originally Posted by kei1309 View Post
    Never clean your own sensor if you feel that you're not up to the task.
    will do. Thanks for the help guys
    Rig: Trusty (dusty) 6 years old Sony A350, Sony 16-105 lens, Sony Flash unit
    Nokia Lumia 1020

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