A&P Just got my 50mm 1.8 in the mail today! ...and now I no longer understand DX

Discussion in 'Lifestyle' started by TtamNedlog, Sep 22, 2007.

  1. TtamNedlog

    TtamNedlog OT Supporter

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    Ok, the 50 1.8 is my second lens. My first being the 18-200 VR, which is a DX lens. Having no other lens to compare the 18-200 to, I could only learn about DX through reading. From what I gathered, on my D80, a 50mm DX would look like what a normal 50mm lens looks like on a film camera. And if I put a normal 50mm on there, it would look about like an 80mm.

    Well I snapped a pic of random crap in my room with the new 50mm lens, then put my 18-200 back on, spun it to 50mm, snapped the same pic, and they look identical in terms of focal length. I thought the 50 1.8 would look like 80mm?


    EDIT: Also, I know many of you have this 50mm lens. Does the aperture ring feel rough and/or cheap when you rotate it? It's no biggy since my camera controls aperture, but I just had to spin it cuz I've never seen an aperture ring before. =p
     
  2. TtamNedlog

    TtamNedlog OT Supporter

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    :rofl: :rofl: :rofl: Going back and reading over my post, I can't help but think:

    No gym for home, work out floor with 30, but is it for 20 like 30 lb when you no lift it to be for men, for 30 lbs instead? or half is 10 for 20 pounds?
     
  3. dooks88

    dooks88 need some bat wings

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    your using a crop body so 50mm will always equal 50mm no matter what lens you use.

    All of your lenses will have the 1.6 (or so) crop factor.
     
  4. ThexToddster

    ThexToddster New Member

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    haha, just enjoy the lens man.

    and don't post snap shots of your dog, flowers, or random shit.
     
  5. TtamNedlog

    TtamNedlog OT Supporter

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    Then I don't understand why they label some lenses as "DX." What's the point?
     
  6. ihkskim

    ihkskim OT Supporter

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    the clarity is much better on a prime lens
     
  7. Tedrzz

    Tedrzz New Member

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    DX don't have aperture rings so they can't be used on film cameras.
     
  8. redna

    redna New Member

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    DX means that it can't be used on a full frame camera because the size of the image that is projected onto the sensor is not large enough to encompass the entire frame of a 35mm negative. They're still measured in standard focal length and for all intents and purposes are the same focal lengths, but a DX lens extends further into the camera body making the image projection smaller.

    Does that make sense?
     
  9. redna

    redna New Member

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    Btw, you could use a DX lens on a film camera, you'd just get a vignetting effect.
     
  10. Hypnos_VI

    Hypnos_VI JENGA!

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    shoulda got a FF...less math. lolz
     
  11. TtamNedlog

    TtamNedlog OT Supporter

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    So why did they invent DX lenses? If a regular and a DX lens perform exactly the same on a crop camera, and a DX lens vignettes on a full frame.... then a DX lens has no benefit at all?
     
  12. fatass

    fatass New Member

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    dx are smaller lighter and cheaper to produce
     
  13. TtamNedlog

    TtamNedlog OT Supporter

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    I see. I guess as disappointing as that is, cheaper lenses are always a good thing.

    All this time, I just thought it worked like this. Found a random image on google to use for an example:




    A 50mm lens on a full frame would look like this:
    [​IMG]




    Then that same 50mm lens on a crop censor would look like this, essentially 76mm:
    [​IMG]




    I understood that much. I just always thought that a 50mm DX lens on a crop sensor would look like the original 50mm on a full frame. Instead it still looks like 76mm.




    In which case the only difference is when you put the DX lens on the fullframe, which looks something like this:
    [​IMG]




    If DX lenses are *significantly* cheaper to produce, then I guess it's good. And it's strange that I care, because I hate film, and as a Nikon shooter I don't have to worry about full frame anyway. I'd like to think some day though I'd get around to affording and having skills that would require a D3, or maybe by that time Nikon would have a slew of full frame cameras. Either way, I just feel that I've limited myself by owning a DX lens(es) if it has no functional advantage, and only a functional disadvantage.
     
  14. GlobeGuy

    GlobeGuy New Member

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    You got most of it right. Depending on what focal length you are on your DX zoom lens you can get a full image on FX.

    edit: Also DX is lighter too, I love light setup definitely makes difference after a day of shooting.
     
  15. mobbarley

    mobbarley Active Member

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    thats interesting, no one would ever say this about ef-s :hs:
     
  16. GlobeGuy

    GlobeGuy New Member

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    ef-s is canon equivalent of DX? If yes, why wouldn't anyone say that its lighter weight was an advantage ??
     
  17. Hypnos_VI

    Hypnos_VI JENGA!

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    cuz ef-s lenses are pieces of shit. lolz

    how can you hate film? *holding back certain comments that will spark a bitch fest...*
     
  18. GlobeGuy

    GlobeGuy New Member

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    I never said I hated film. Your quote got messed up.
     
  19. jared_IRL

    jared_IRL OT Supporter

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    wait...

    So you're suprised that they made a series of lenses specific to digital cameras, when their old lenses were .5x too big, and had the added complexity of the aperture ring?

    If you're making lenses, and you discover that your lenses are being made with .5x too much glass, and have a manual setting that does not function with any camera made since 1985, why would you continue to do so?

    DX lenses are made to fit digital sensors, and made to work on digital SLR's.

    Your average photo geek doesn't want to spend 500+ for a lens, and doesn't want to deal with having to make sure the aperture ring is closed every time they load a lens. They also don't want heavy, big, stupid metal lenses.


    So thats what gets built. Compact, small, plastic, lenses.

    There's really nothing wrong with DX lenses. They work just fine. They're just consumer DSLR specific lenses.
     
  20. Hypnos_VI

    Hypnos_VI JENGA!

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    so it did, meant to quote OP
     

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