Megapixel of the Eye

Discussion in 'Digital Discussion & Q&A' started by iflynething, Jan 19, 2007.

  1. iflynething

    iflynething TPF Noob!

    Joined:
    Oct 26, 2006
    Messages:
    1,347
    Likes Received:
    0
    Location:
    South Carolina USA
    Can others edit my Photos:
    Photos OK to edit
    I have always though of how the eye sees and relating it the a camera: DSLR or Film..

    I always think, why does it take forever for the camera to focus when there is dim light...heck most of the time it doesn't focus (unless it's manual focus, mostly). Well, I like to play around and I will close one eye and get close to something. Anyways, I will put that in focus, then to my phone, then to the carpet or something. Just to play

    Well what about the megapixel of the eye. Is there a way to measure, if your eye was digitized, what would it be?

    Odd question I know, but any though


    Just some random thoughts

    ~Michael~
     
  2. auer1816

    auer1816 TPF Noob!

    Joined:
    Jan 14, 2007
    Messages:
    139
    Likes Received:
    0
    Can others edit my Photos:
    Photos OK to edit
  3. iflynething

    iflynething TPF Noob!

    Joined:
    Oct 26, 2006
    Messages:
    1,347
    Likes Received:
    0
    Location:
    South Carolina USA
    Can others edit my Photos:
    Photos OK to edit
    That is VERY interesting. WOW. I really didn't understand the equations. I just skimmed over it. I think I might sit down and read the whole thing.

    Thank you for the link and the information.

    I guess my question is answered in one post.

    Thanks

    ~Michael~
     
  4. darich

    darich TPF Noob!

    Joined:
    Jan 22, 2005
    Messages:
    1,230
    Likes Received:
    1
    Location:
    Near Lanark, Scotland
    Can others edit my Photos:
    Photos NOT OK to edit
    I'm not convinced that's entirely true.

    yes the eye can see lots of detail and the brain adjusts for 2 eyes etc but when you look at one item eg your pc monitor you can see the keyboard in front of it and the speakers to the side, but can you see any details?
    No - you have to look at them to see the detail. The article even says that and then says that the eyes moving around "paints" in the detail. I can do the same thing with my camera but i don't claim to have a 576mp camera.

    what you see and what you look at are 2 different things and i think the linked site is using what the eye can see as being highliy detailed eg 120degee vision - no one can see detail at 60degrees off to either side without actually looking that way. Yes you'll see a person or car or object coming at you and moving out the way but if it's something that's been thrown you don't know if it's paper, stone, wood, ploystyrene unless you look at it.

    And another thing - when i take shots with my 5D i can see detail at 100% magnificationh that my eye could never pick out. An example was a shot of my cat. No way could i see the details on her tag from around 10feet but when i viewed the image at 100% i can see the logo and contact details.

    I think that article is quite misleading and based on some incorrect assumptions.
     
  5. fmw

    fmw No longer a newbie, moving up!

    Joined:
    Sep 30, 2006
    Messages:
    2,603
    Likes Received:
    137
    I'm Darich on this one. You need to be careful about information on the internet and I think this is one of them with which you need to be careful.

    The auto focus issue is simply a matter of how AF systems are designed. They just need enough light to work properly. If you are in a hurry to focus in dim light then manual focus may be the answer for you.
     
  6. ksmattfish

    ksmattfish Now 100% DC - not as cool as I once was, but still

    Joined:
    Aug 25, 2003
    Messages:
    7,021
    Likes Received:
    34
    Location:
    Lawrence, KS
    Can others edit my Photos:
    Photos NOT OK to edit
    Many people attribute issues of image quality to megapixels, but among camera manufacturers the only common definition of the term "megapixel" is that it describes how many photo receptors there are on a digital sensor (look into the many "all megapixels are not created equally" threads here and elsewhere).

    According to info I googled, the human eye has 130,000,000 rods, and 7,000,000 cones. So each human eye has 137,000,000 photo receptors, and the combined megapixels of both eyes would be 274 mp. Just like with cameras, knowing this number doesn't tell us much about ability, quality, etc....
     
  7. auer1816

    auer1816 TPF Noob!

    Joined:
    Jan 14, 2007
    Messages:
    139
    Likes Received:
    0
    Can others edit my Photos:
    Photos OK to edit
    What exactly does 100% magnification mean? If I print that picture at 720ppi is that 100%? Or do you mean viewing it on your screen at 72dpi? Ksmattfish is right, the number of photo receptors doesn't tell us anything about quality.

    It's an interesting thought to compare our eye to an image sensor, but I think we're comparing apples to oranges. The eye doesn't see the world the same way an image sensor does.

    Regardless, I think the human eye makes for a better vision system than a camera.
     
  8. morydd

    morydd TPF Noob!

    Joined:
    Apr 19, 2006
    Messages:
    499
    Likes Received:
    0
    Location:
    Chicago
    Can others edit my Photos:
    Photos OK to edit
    Of course, a major part of the reason that the eye makes a better vision system is the gigantic processor sitting 3 inches behind it. :)
     
  9. iflynething

    iflynething TPF Noob!

    Joined:
    Oct 26, 2006
    Messages:
    1,347
    Likes Received:
    0
    Location:
    South Carolina USA
    Can others edit my Photos:
    Photos OK to edit
    Thank you for all your different perspectives

    Darich,
    I must agree with youthat some of the information on that site is little misleading. I must say that when you look at something you have to actually be looking at it. You do have periferial (sp?) vision but youcant see things in detail, like yousaid, at that 120° or 180°.

    I think one thing I didn't like about that link was there was alot of Jargon used which I, personally didn't understand. Some of it I did bcause I'm 18 and in high school and talk,or have talked about it in my math classes. But for the most part I skimmed for what answer he was getting and just went with that.

    Fmw,
    It would be best to use the manual focus when you are in dim light because the camera just can't do the work in low light conditions.

    auer1816,
    We are compaing apples to oranges. We could never compare the eye to a camera but Ijust wanted to get a rought estimate as to if the eye were a digital sensor then just what would it be for our eyes.

    So from what kmattfish said and what was presented on the website, we have between 274 and 576 megapixels of the eye. But that's just a rough estimate and I know all people see differently.

    Thanks for all the insights

    ~Michael~
     
  10. darich

    darich TPF Noob!

    Joined:
    Jan 22, 2005
    Messages:
    1,230
    Likes Received:
    1
    Location:
    Near Lanark, Scotland
    Can others edit my Photos:
    Photos NOT OK to edit
    ppi or dpi is noting to do with magnification.
    Whatever processing package you use, you'll have a zoom function. you can zoom in and out of your image to work on areas or pick out details.

    When viewing one of my shots a full screen it's about 8-12% of full size but it doesn't matter whether it's 72dpi or 1000dpi - i can still only see it at 8-12%

    the number of dots or points per inch makes no difference to the quality or amount of image i can see on the screen at any given magnification.
     
  11. Alex_B

    Alex_B No longer a newbie, moving up!

    Joined:
    Aug 30, 2006
    Messages:
    14,491
    Likes Received:
    206
    Location:
    Europe 67.51°N
    Can others edit my Photos:
    Photos NOT OK to edit
    Wehn I speak of looking at an image on screen at 100%, I refer to 1 screen pixel being 1 image pixel, no interpolations to be made.

    of course, then my screen is not large enough to see 100% of the image area, but it might be only capable of showing less than 10% of it .. maybe this creates some of the confusion here :p
     
  12. iflynething

    iflynething TPF Noob!

    Joined:
    Oct 26, 2006
    Messages:
    1,347
    Likes Received:
    0
    Location:
    South Carolina USA
    Can others edit my Photos:
    Photos OK to edit
    Woah.....

    ~Michael~
     

Share This Page