Site Sponsors
Results 1 to 12 of 12

Thread: MF "look" vs DSLR "look"

  1. #1
    Super Duper
    Senior Member

    Join Date
    Dec 2007
    Location
    Germany
    Posts
    3,623
    Post Thanks / Like

    MF "look" vs DSLR "look"

    There is one thing which I believe to see again and again:
    With my MF images the transition between the focused distance (sharp area of the image) and the out of focus areas seems (much) smoother compared to 35mm images.
    I would even say the transition between sharp and unsharp looks more film like with MF compared to 35mm-sized sensors.

    I wonder why? Is it the size of the sensor or could it be that sharpening-algorithms of AA-filtered images produce a different look.

    Or is it just my illusion?

    I gave up to try to rum comparison test between systems and formats but just judge from using the gear and look at the overall results.

  2. #2
    Super Duper
    Senior Member

    Join Date
    May 2008
    Location
    Manchester/Jerusalem
    Posts
    2,652
    Post Thanks / Like
    Images
    290

    Re: MF "look" vs DSLR "look"

    I assume it the fact that you are using longer lenses closer up with medium format so the focus fall off is faster.
    I am not a painter, nor an artist. Therefore I can see straight, and that may be my undoing. - Alfred Stieglitz

    Website: http://www.timelessjewishart.com

  3. #3
    Senior Member
    Join Date
    Dec 2007
    Location
    N.S. Canada
    Posts
    2,010
    Post Thanks / Like

    Re: MF "look" vs DSLR "look"

    By smoother you mean more gradual vs. a sudden almost artificial-looking transition?

  4. #4
    Sr. Administrator Jack's Avatar
    Join Date
    Oct 2007
    Location
    Los Altos, CA
    Posts
    10,486
    Post Thanks / Like
    Images
    1031

    Re: MF "look" vs DSLR "look"

    It's real. It has been there all along with film too. It is the combination of larger formats using longer lenses from the same shooting positions to provide the same net AoV, but with correspondingly less DoF. So we see it in the image as the DoF falling off faster. Also, more total pixels between the given falloff points is equivalent to larger areas of emulsion to spread the (now steeper) transition over; hence we get a net smoother -- and at the same time a more obvious -- transition.

    Cheers,
    Jack
    home: www.getdpi.com

    "Perfection is not attainable. But if we chase perfection, we can catch excellence."

  5. #5
    Senior Member
    Join Date
    Dec 2008
    Location
    Los Gatos, CA
    Posts
    340
    Post Thanks / Like

    Re: MF "look" vs DSLR "look"

    Quote Originally Posted by Jack Flesher View Post
    It's real. It has been there all along with film too. It is the combination of larger formats using longer lenses from the same shooting positions to provide the same net AoV, but with correspondingly less DoF. So we see it in the image as the DoF falling off faster. Also, more total pixels between the given falloff points is equivalent to larger areas of emulsion to spread the (now steeper) transition over; hence we get a net smoother -- and at the same time a more obvious -- transition.

    Cheers,
    Jack,

    But if you compared, for example, an 85mm f/1.4 lens on 35mm and a 150mm f/3.5 lens on 645, you could shoot comfortably at the same DOF on both cameras. Say, f/2 vs f/4.

    Would this negate a lot of the expected difference, or is there some other difference between "equivalent DOF" on the two formats that isn't explained in a single number?

    Greg

  6. #6
    Super Duper
    Senior Member

    Join Date
    Dec 2007
    Location
    Germany
    Posts
    3,623
    Post Thanks / Like

    Re: MF "look" vs DSLR "look"

    Quote Originally Posted by robmac View Post
    By smoother you mean more gradual vs. a sudden almost artificial-looking transition?
    yes exactly-not as harsh.

  7. #7
    Sr. Administrator Jack's Avatar
    Join Date
    Oct 2007
    Location
    Los Altos, CA
    Posts
    10,486
    Post Thanks / Like
    Images
    1031

    Re: MF "look" vs DSLR "look"

    Quote Originally Posted by gsking View Post
    Jack,

    But if you compared, for example, an 85mm f/1.4 lens on 35mm and a 150mm f/3.5 lens on 645, you could shoot comfortably at the same DOF on both cameras. Say, f/2 vs f/4.

    Would this negate a lot of the expected difference, or is there some other difference between "equivalent DOF" on the two formats that isn't explained in a single number?

    Greg
    Well here is the issue: First, the 85 on 35mm is closer to a 120 on MF full frame. So shooting both from say a 5 meter distance, you'd have almost identical DoF and framing if you shot the 85 (on the 35) at f1.4 and the 120 (on MF) at f2. However, since you usually have a greater number of pixels (or more film area with film) between any two points with MF, the transition between any two given points should always appear smoother off the MF sensor, all else equal. IOW, more information spread across the same visual distance equals finer granularity across the total transition, and finer granularity equals a smoother total transition.

    Caveat: With digital in the case where you compare identical sensor resolutions, the granularity difference is mitigated. For example, if we have a 22MP 35 sensor without AA filter to a 22MP MF sensor without AA filter using the above lenses, apertures, shooting distances AND assuming the lenses have equal or higher resolution than their respective sensors, then the "granularity" between any two points should be identical, so the resulting "smoothness" should also appear identical. Of course other sensor aspects like the AA filter will alter the perception of smoothness, and finding a 35mm digital sensor comparable to a MF sensor -- ie one without AA filter -- can be problematic...
    Jack
    home: www.getdpi.com

    "Perfection is not attainable. But if we chase perfection, we can catch excellence."

  8. #8
    Senior Member
    Join Date
    May 2008
    Location
    Hong Kong / Asia
    Posts
    524
    Post Thanks / Like

    Re: MF "look" vs DSLR "look"

    Quote Originally Posted by Jack Flesher View Post
    Well here is the issue: First, the 85 on 35mm is closer to a 120 on MF full frame. So shooting both from say a 5 meter distance, you'd have almost identical DoF and framing if you shot the 85 (on the 35) at f1.4 and the 120 (on MF) at f2. However, since you usually have a greater number of pixels (or more film area with film) between any two points with MF, the transition between any two given points should always appear smoother off the MF sensor, all else equal. IOW, more information spread across the same visual distance equals finer granularity across the total transition, and finer granularity equals a smoother total transition.

    Caveat: With digital in the case where you compare identical sensor resolutions, the granularity difference is mitigated. For example, if we have a 22MP 35 sensor without AA filter to a 22MP MF sensor without AA filter using the above lenses, apertures, shooting distances AND assuming the lenses have equal or higher resolution than their respective sensors, then the "granularity" between any two points should be identical, so the resulting "smoothness" should also appear identical. Of course other sensor aspects like the AA filter will alter the perception of smoothness, and finding a 35mm digital sensor comparable to a MF sensor -- ie one without AA filter -- can be problematic...
    There is more, is it not?

    Lens Optics - optical path design from subject, lens elements to image plane, including nodal point, depth of field, depth of focus etc all and everything making a difference.

    Digital - the sensors for MF are able to yield higher image quality, partly because designed primarily for the native ISO which is where they excel.

    Resolution - For film grain size is different. For digital the pixels can be larger for MF.

    Image Plane - Larger capture area of light on MF (something most seem to overlook nowadays because sold on MP instead).

    The law of nature remains - no matter the MPs... a larger capture area yield higher quality.

    Regards
    Anders

  9. #9
    Senior Member
    Join Date
    Dec 2008
    Location
    Los Gatos, CA
    Posts
    340
    Post Thanks / Like

    Re: MF "look" vs DSLR "look"

    Okay, guys...I get it. I was referring specifically to the physics of the DOF, and if the "rolloff" was steeper or something. Ben's reply (the first one) implied there was something to this effect.

    It sounds like technically, the images will be "similar", if the DOF calculator matches up the apetures and sensor sizes, but you'll still get all the benefits of the larger sensor.

    Don't worry, I did the test between the $1200 35mm lens and the $50 MF lens, and the cheap one won.

    Greg

  10. #10
    Senior Member Lars's Avatar
    Join Date
    Nov 2007
    Location
    Sunnyvale, California
    Posts
    1,811
    Post Thanks / Like
    Images
    19

    Re: MF "look" vs DSLR "look"

    Another explanation for why DOF character changes with sensor sizes:

    When you step up from 35mm to MF, you scale the camera side of the system - sensor, lens focal length. But if subject size and distance remains fixed then the entire system has not been scaled up. So relatively speaking, the subject is now smaller and closer to the camera (relative to lens/sensor size).

    So relatively speaking you are focusing closer, which means more narrow DOF.

    (I hope that was not too confusing, I have to admit that I confused myself a little there for a while.)
    Monochrome: http://mochro.com

  11. #11
    Senior Member
    Join Date
    Dec 2008
    Location
    Los Gatos, CA
    Posts
    340
    Post Thanks / Like

    Re: MF "look" vs DSLR "look"

    Quote Originally Posted by Lars Vinberg View Post
    So relatively speaking you are focusing closer, which means more narrow DOF.
    That sentence is all that we need.

    DOF is a percentage of subject distance, depending on all those other factors. Get closer, get shallower.

    It's forcing myself to shoot f/22 on macros that is the hard part.

    Greg

  12. #12
    Sr. Administrator Jack's Avatar
    Join Date
    Oct 2007
    Location
    Los Altos, CA
    Posts
    10,486
    Post Thanks / Like
    Images
    1031

    Re: MF "look" vs DSLR "look"

    Quote Originally Posted by Anders_HK View Post
    There is more, is it not?
    Not really. Once you eliminate effects of the AA filter and grant that the lenses can outresolve the sensor -- as I said above -- then the rest is moot.

    The law of nature remains - no matter the MPs... a larger capture area yield higher quality.
    Huh??? Nope. For example, assume a 36x48 sensor with 1mm sensor sites. It would resolve a total of 36x48 or a whopping 1728 pixels ---- a far cry from say the 5D's or M8's much smaller 11 million pixel sensors --- with almost 100 times the linear resolution, those sensors will show, well, 100 times smoother transitions than the larger, lower rez sensor above. Heck, a cell phone camera would do better!


    Now at the same sensor density, yes, a larger sensor will always have more pixels and ergo, more points for smoother transitions.
    Jack
    home: www.getdpi.com

    "Perfection is not attainable. But if we chase perfection, we can catch excellence."

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •