Canon 70-200mm f/4 and out of focus background

Discussion in 'Canon EOS' started by oliver_wang|1, May 14, 2010.

  1. hi, guys,
    I am thinking of getting the Canon 70-200mm f/4 primarily for out of door portrait. However, I am a bit concerned on its capability of throwing background of focus. I remember Phils's review mentioned something like f/2.8 at 100mm is crucial for out of focus background portrait.
    Apparently, I am not going for f/2.8 L for budget issues. I'd appreciate if f/4 owners can share their experience and samples on this len's out of focus capability.
    Thanks very much.
    Oliver
     
  2. Here's an example, 70-200/4L IS, ISO 200, 97@5.6, distance 3m
    00WSvo-244215584.jpg
     
  3. Oliver,
    There is no effective difference between the f2.8 and f4 once you are at f4. So here is one taken with an f2.8 at f4, 1/125 sec, iso 200 @ 200mm.
    Subject/background separation is the key, get them as far apart as possible and get as close to the subject as possible with the longest end of the zoom, then the backgrounds will melt away.
    Hope this helps.
    00WSvw-244217584.jpg
     
  4. Here's a review with some hopefully useful sample shots -
    http://www.the-digital-picture.com/Reviews/Canon-EF-200mm-f-2-L-IS-USM-Lens-Review.aspx
    The lens being reviewed is actually the 200/2. But he's got sample shots showing the background blur at various apertures. f/2.8 is noticeably more diffuse than f/4, but f/4 is still quite good. And as Scott says, getting the subject away from the background can make a world of difference.
    If you're only shooting portraits you might consider a prime, like the 85/1.8, 100/2, 135/2, or 200/2.8.
     
  5. I shoot a lot of close-ups with the 70-200mm f/4 and it produces very nice bokeh.
    Dan
     
  6. William Michael

    William Michael Moderator Staff Member

    What Camera, Oliver?

    "There is no effective difference between the f2.8 and f4 once you are at f4. So here is one taken with an f2.8 at f4, 1/125 sec, iso 200 @ 200mm."

    But the camera does . . . especially when you are in that tight.

    Nice portrait, Scott.

    You should expect a little more DoF at F/4 if you have an APS-C camera, than what Scott got with his shot - at a guess - you'd get the hairline and just the beginning of the ears - now that might or might not make a difference to you - I don't know.

    But that has no impact on the Bokeh "melting away" it only has to do with the shallowness of the DoF you can get at f/4 . . . if you have an APS-C camera.

    The 85/1.8 is very nice Portrait Lens when used wide open on an APS-C and can give you the very shallow DoF (and more) others get with the F/2.8L zoom . . . just thinking.
    WW

    (I am assuming Scott did use a 1D)
     
  7. Much appreciated of you guys sharing wonderful samples.
    @William, I am using a 40D.
    I understand the difference it will make when I can move the subject away from the background. However, under circumstances, I may not have that much of flexibility, or the patience of the subjects. Thus the quest of exploration for the "boundary" conditions where I can have some confidence of a shallow DOF without moving subject around too much. Nonetheless, the point is duly noted.
    Many thanks to all
    Oliver
     
  8. William Michael

    William Michael Moderator Staff Member

    "Thus the quest of exploration for the "boundary" conditions where I can have some confidence of a shallow DOF without moving subject around too much." . . .
    Then, on this point you make and considering you have a 40D, you should investigate the 85/1.8 or the 100/2.
    Some 85mmF/1.8 at 1.8: http://www.photo.net/photodb/folder?folder_id=925231
    WW
     
  9. Hi Oliver, you may want to check out below link. There you can select the camera, lens and aperture to see how pictures taken with a certain combo can look like: http://www.pixel-peeper.com (start picking the lens).
    Timm
     
  10. Hi William,
    Thanks for the compliment, and yes, it was done with a 1D (best $400 secondhand camera out there), so a 1.3 crop. Very good points though, the 40D would give the head slightly more DOF and a 5D slightly less, if I moved to get the same framing at 200mm, but the background should be very similar.
    Oliver,
    It is working the scene with the lens you have that gets you the results you want. The guy above was standing under a tree and was very close to it, I got his attention and then moved around until he lined up with the other side of the road to get the separation I wanted. Below is another shot in the sequence, I think it was the first, it, conversely, was shot at f2.8 and 70mm, it sets the scene but the background is too busy. Hope these help, the f4 really isn't a step down, it is just another tool, for sure the f4 is way more comfortable on a weeks trekking :)
    Take care, Scott.
    00WT23-244293584.jpg
     
  11. I have both the 70-200 f2.8 (non IS) and the 70-200 f4 IS. I primarily use the f2.8 lens for sports with the F4IS being the one I normally carry around. For portrait use both work fine - the F2.8 lens possibly being able to seperate the subject from the background slightly better. Neither are the best portrait lenses but still take great images. I have the 85 f1.8 and find that it is really little fifferent for portrait use than the 70-200 f2.8 or my 100 f2.8 L IS Macro. At the moment the macro lens is my favourite for portrait use but I plan to buy the 85 F1.2 when I can afford it as this lens really does make portraits pop. I have two of the older FD 85 F1.2 lenses and I find this lens remarkable for portraits. Once past this specialist lens I find that several lenses work well.
    In my opinion there is little to choose between the 70-200 F2.8, 85 F1.8 and 100 f2.8 Macro on a full frame body with the 70-200 F4 IS being very similar performance. I think you will like the F4 lens as not only is it cheaper it is also much more portable.
     
  12. It is working the scene with the lens you have that gets you the results you want.
    Good point.
    @Timm, pixel-peeper seems to be very interesting web site, I will explore more.
    @William, I do have 85mm/1.8, wonderful lens. For whatever reason, at times, I am inching for a little bit more zooming flexibility even though the same photo can be made by working with the scene.
    Best to y'all.
    Oliver
     
  13. This was shot with the f2.8 IS version, but at f5.6. Per the other posters, subject to background separation is at least as important as low f-stop, and even higher up numbers like this can deliver good results. I'm still thinking about picking up the f4.0 version, lighter (much!), more compact, sharper, newer IS, and so on.
    00WT70-244343584.JPG
     
  14. Depth of field, or blur near the plane of focus, is determined by the aperture fraction for a given FoV. Background blur for detail far behind the plane of focus is determined by the physical aperture size.
    A 200mm at f/4 (50mm aperture) has more background blur than a 100 at f/2.8 (36mm aperture) when the subject is framed identically and the background is some distance behind the subject. Of course your working distance with the 200mm for a portrait might be excessive, and you might not care for the degree to which it flattens perspective. Also, you might not be able to put that much distance between the subject and the background.
    All that said: the 70-200 f/4L has nice bokeh and is capable of throwing a background OOF with proper distances (camera to subject to background). It doesn't cost that much to add an 85 f/1.8 as well, which gives you a shorter working distance and less DoF for tight spots.
     
  15. google "depth of field calculator" and make u up some charts,
     
  16. Mendel I shoot the old 70-200 f2.8 non IS for sports and have the new 70-200 F4 IS as a general prupose lens. You will not regret getting the F4 and if you are like me the F2.8 will only leave the house when you really think you need the speed.
     
  17. It will work fine if you are close to your subject and your background is far away. f/2.8 gives you a little more blur power, but the same principle applies. Close to subject; far from background.
     
  18. William Michael

    William Michael Moderator Staff Member

    “@William, I do have 85mm/1.8, wonderful lens. For whatever reason, at times, I am inching for a little bit more zooming flexibility even though the same photo can be made by working with the scene.”

    OK, I get it. I was just making sure you had travelled all avenues before buying.
    As well as all the other great advice here, I agree especially with Philip Wilson – I too have the 70 to 200 F/2.8L USM, and I use it almost exclusively for sport - and I have thought long and hard about buying the 70 to 200 F/4 IS USM for the same reasons Philip outlines - as a walkabout lens (the other one I think about to fill this gap for me, is the 24 to105F/4 IS).
    I also have and use the 100F/2.8 Macro for Portraiture. (examples in my Portfolio here).
    I use both APS-C and FF Camera Bodies with all my lenses.
    I think you will love the 70 to 200f/4 IS USM . . . and you should have already bought it by now.
    All the best,
    WW
     

Share This Page