EOS 20D...1.6x Crop Factor...Do you actually see it while shooting?

Discussion in 'Digital SLR' started by Jay Beckman, Dec 19, 2004.

  1. Jay Beckman

    Jay Beckman Guest

    Greetings All...

    I have made the jump from Canon FD (T90, 300/f4, etc...) to the EOS 20D.

    I think I understand the crop factor and why it produces relative
    magnification. But, I'm still a little fuzzy on what manifests itself in
    the viewfinder.

    Just as a point of reference, let's say that from 50 yards away, with a
    300mm lens on a T90, I can get a six foot tall person framed head to toe.

    Now, without changing my distance from the subject, I go to frame the same
    shot with a 300mm lens on a 20D...what will the ol' analog eyeball actually
    see in the viewfinder?

    Do I see the same image I saw with the T90 (knowing that my subject will
    actually be cut off at the waist when I play back that shot), or will I
    actually SEE the 1.6x at work and get a visual image that shows my subject
    framed from head to waist as if shot with a 480mm lens ?

    In other words, is the 20D viewfinder "tweaked" such that the crop factor is
    visually apparent when you are shooting, or do you have to constantly think
    "Shoot Loose!" to accomodate the crop factor???

    Am I comparing apples to oranges? Or, should I just purge my brain of any
    35mm memories and always be sure that I have an extra 30 yards of real
    estate behind me so that I can shoot from 80 yards away instead of 50? :O)

    So far, I'm very happy with the first dozen or so images I've gotten with
    the 20D, but I wanted to get a better handle on all of the above as I move
    forward with lens choices and begin to fill out my digital system.

    Thanks in advance,

    Jay Beckman
    Chandler, AZ
    Jay Beckman, Dec 19, 2004
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  2. Jay Beckman

    Colm Guest

    How did the results compare to what you saw in the viewfinder?
    Colm, Dec 19, 2004
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  3. Jay Beckman

    Jay Beckman Guest


    I don't have any results from which to draw comparisons yet...that's kinda
    why I'm asking the question. ;O)

    Maybe I should have said: Is what I see in the viewfinder exactly what is
    going down on disk, or do I always have to think "Shoot Loose" because the
    actual picture being recorded is cropped tighter?

    From a logistical point of view, this is a key question. There are places
    I've shot or that I like to shoot that may not allow me the option of
    backing off more to accomodate a "longer lens" and so I might only want a
    200mm lens (for the effective yield of 320mm) instead of getting a 300mm
    lens and having to physically move farther back to accomodate the (virtual)
    480mm image.

    I hope this clarifies my point.


    Jay Beckman, Dec 19, 2004
  4. Jay Beckman

    Mac Tabak Guest

    Jay, what you see is nearly what you get, it's about 95% through the

    Mac Tabak, Dec 19, 2004
  5. Jay Beckman

    Alan Adrian Guest

    Considering you have the camera with you.... this is an easier thing to test
    for than asking.... =)

    But anyways... in my viewfinder, If I line the top edge of the viewfinder up
    exactly with the top of someone's head... I get a bit more space above in my
    image... so the viewfinder shows about 95% of what you get... sort of like
    on your old analogue camera.

    Alan Adrian, Dec 19, 2004
  6. Jay Beckman

    Colm Guest

    Waiting on the film to come back, eh? :)

    What you see is more or less what you get. It would be quite a pain to have
    to imagine the crop in your head every time you took a shot. Simply think of
    your 50mm as an 80mm. Other than that, it behaves as a normal slr.
    Colm, Dec 19, 2004
  7. If you stick the 20D in exact the same position as the T90, you will
    see a person where the head and feet are outside the frame. The field
    ov view in viewfinder will be identical to what you'd see if you stuck
    a 480 mm lens on your T90.
    The latter - if you tilt the camera slightly up to get the head in
    the shot. This should be simple to verify if you still have the
    film body.
    The viewfinder in the 20D look down on a matte focusing screen that
    matches the smaller sensor in the camera (it shows about 95% of what
    you capture - I believe the T90 viewfinder also show about 95% of
    what you get on the film).
    You don't move back, moving back changes perspective. You use a wider
    focal length to get the same field of view as your film body would
    give you. For instance, instead of a 300 mm on a T90, you zoom out to
    188 mm on a 20D.
    Gisle Hannemyr, Dec 19, 2004
  8. Jay Beckman

    Jer Guest

    Let me see if I understand your question... you've said you understand
    that the FOV of the lens will be different, and you want to know if your
    FOV in the viewfinder will reflect this difference. Right?
    Jer, Dec 19, 2004
  9. Jay Beckman

    Skip M Guest

    Skip M, Dec 19, 2004
  10. Jay Beckman

    Alan Browne Guest

    My film camera has a 100% viewfinder and it bothers me that the DSLR's have gone
    to sub-100% viewfinders when the vf optics are less expensive with cropped sensors.
    Alan Browne, Dec 19, 2004
  11. Jay Beckman

    Skip M Guest

    Not all DSLRs have less than 100% viewfinders, the Canon 1 series has a 100%
    viewfinder, and I think some, if not all, of the Nikons do, too.
    Skip M, Dec 19, 2004
  12. Jay Beckman

    dylan Guest

    Take a 35mm negative (36mm x 24mm) and draw a rectangle the size of a APS
    negative (22.5mm x 15mm) in the centre of it and that's the picture your 20D
    will see.

    A 300mm will give the coverage of a 300x1.6 (420mm) on the 20D.

    The viewfinder will show 95% of the APS size image.
    dylan, Dec 19, 2004
  13. Jay Beckman

    dylan Guest

    try 300x1.6 = 480 !!

    dylan, Dec 19, 2004
  14. Jay Beckman

    Todd H. Guest

    What you see in teh viewfinder is what you'll get. Head to waist
    should be what you see in your example.

    Yeah, if you just clear your head of what a given focal length gives
    you in terms of field of view and recalibrate the noggin to the new
    format, you'll be good.
    Todd H., Dec 19, 2004
  15. Jay Beckman

    Jeremy Nixon Guest

    Only top-end film SLRs ever had 100% viewfinders, anyway. Some of the
    top-end digitals have them, too.

    What bothers me is that they tend to keep the same magnification in the
    viewfinder as with full-frame. That is, the viewfinder in the D70 is
    a cropped version of a 35mm viewfinder; the image is smaller, rather
    than having more magnification. That's annoying. I should see the same
    thing (well, roughly) looking through a 35mm lens on digital as I see
    with a 50mm lens on film, but that's not the case; a 50mm on digital
    results in no visual magnification, despite it being a moderate telephoto.

    I'm hoping for a better viewfinder on the D2x.
    Jeremy Nixon, Dec 19, 2004
  16. Jay Beckman

    Alan Browne Guest

    Page 159 of the Canon 20D manual states that the 20D viewfinder is 95% (V and
    H), so the image will be slightly outide what you see in the VF.
    Alan Browne, Dec 19, 2004
  17. Jay Beckman

    Jay Beckman Guest


    Thank you

    Jay Beckman, Dec 19, 2004
  18. Jay Beckman

    Jay Beckman Guest


    That is exactly the question I'm asking. It has been answered to my
    satisfaction, thank you.

    Jay Beckman, Dec 19, 2004
  19. Jay Beckman

    John Francis Guest

    Not on many modern film SLRs :-( While the viewfinders on my older
    cameras are roughly life-size with a 50mm lens mounted, those on the
    later cameras, with more in-viewfinder information displays, have
    shrunk the angle of view allocated to the actual viewfinder display.
    Nowadays you need to mount a 70mm or 80mm lens to get a viewfinder
    display that roughly matches your normal vision.

    Still, that means that if your DSLR, with a 50mm lens attached, were
    showing you the smaller angle of view in the same physical area, it
    would be approximately life size. But, as you noticed, that often is
    not the case; the viewfinder image area is even smaller in the DSLR.

    One notable exception in the lower-priced entries is found in the
    Pentax *ist-DS; the viewfinder magnification of that camera with a
    50mm lens mounted is close to life size. Do a side-by-side test of
    that camera and a Nikon D70 or a Canon 300D - you'll be impressed.
    John Francis, Dec 19, 2004
  20. Jay Beckman

    Alan Browne Guest

    That's essentially what I said above. It is the result of making the mirror and
    VF optics smaller and cheaper. It would even be nice to have 125% viewfinders
    which would be nice for action shooting. However, the tradeoff in an SLR
    viewfinder would be a smaller 'true' image area (0.6x or so).

    Alan Browne, Dec 19, 2004
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