Click here for picture

I feel like the blur is not natural. Looks like it was Gaussian Blurred with the couple as the center. What do you guys think?

  • 2
    I think it's an interesting question, I just find the idea of "naturally occuring bokeh" a bit amusing ;)
    – gerikson
    May 20, 2011 at 9:54
  • The only contribution I can make is to note that you have a spelling mistake in your title ('occurring').
    – bryn
    May 20, 2011 at 10:53
  • @gerikson Totally, my first thought was "is this bokeh naturally occurring, or was it planted by someone? If so who?" Perhaps we'll never know...
    – Matt Grum
    May 20, 2011 at 11:13
  • 2
    @bryn — you don't need to complain about typos. Instead, use the edit link to fix them. :)
    – mattdm
    May 20, 2011 at 11:35
  • 2
    @mattdm: The 6-character minimum edit is infuriating to me when I'm trying to copyedit. (Though I don't think that applies to titles.)
    – coneslayer
    May 20, 2011 at 13:37

5 Answers 5


The bokeh behind the couple looks normal, the sides seem to have had a gaussian blur applied to give a fake tilt shift effect.

The telling factor is the highlights. The light coming from the windows is much brighter and ought to have a sharp cutoff when rendered out of focus. Gaussian blur gives a soft edge to such highlights.

edit: reading the text of the image, the photographer states that this was created as a "bokeh panorama" (otherwise known as a panorama) hence the apparent shallow depth of field. This doesnt quite wash as there are elements of the background that are the same distance as the couple and hence ought to be in focus.

My guess is now that the photographer took a tele shot of the couple and a wide shot of the surround and blurred the latter to match, the blur in the corners just doesn't look like lens blur to me.

  • Exactly as I thought. Thanks for confirming my observation. :)
    – rabbid
    May 20, 2011 at 9:31

I don't think either field curvature or a T/S lens could reasonably account for what I'm seeing here. A T/S lens can change the orientation of the plane that's in focus, but you still get a plane. Field curvature can warp that so it's no longer planar, but it still defines a virtual "surface" that's focused.

If we look at the floor (for one example) a few feet to the left or right of the couple, there's simply no transition from out of focus to in-focus to back out of focus. Perhaps a comparison would be in order:

enter image description here

This shows a distinct line across the floor that's in focus. With field curvature, that line would be curved instead of straight. With a T/S lens, it could be an an angle instead of perpendicular to the camera. The subject picture has nothing of the sort -- no ling across the floor that comes into focus at all, straight or curved.

I suppose if you wanted to badly enough, a combination of extreme tilt with field curvature and focus stacking could almost produce this effect. You'd basically have to tilt the lens so much the focus plane would normally be almost parallel to the floor, but have a lens with lots of field curvature. You'd then do a stack, moving your focus from slightly above the floor up toward the head of the couple.

Offhand, the only lens I know of that would even be sort of close to producing that amount of field curvature would be the old, long-since discontinue Minolta VFC (variable field curvature) macro. With one of those on a T/S mount in front of something like a u4/3rds, I suppose you might be able to at least get sort of close. Even then, of course, Matt Grum's point about the windows would still stand though.

  • I wasn't suggesting field curvature was responsible for the image (which the photographer states was 'shopped) just that is was theoretically possible optically to have a subject in focus and the ground either side not to be, though it would take a pretty extreme lens to produce the effec.
    – Matt Grum
    May 20, 2011 at 16:09
  • 1
    @Matt: right -- I wasn't really trying to argue your point. Rather, there are quite a few people who've never use them, who tend to treat T/S and/or field curvature as almost magical, so I thought I'd try to point out a little more about what kind of things they can and can't do. Bottom line is that I agree with you on both counts: it's theoretically possible, but extremely unlikely. May 20, 2011 at 16:14

I think this was achieved with the "Brenizer method".

Essentially it is the same concept used by landscape photographers known as panorama stitching except instead of stitching a bunch of horizontal shots together to form a wide image, the images are horizontally and vertically stitched to create a wide and tall image not unlike a square. And because you are stitching together many files, you are creating a very high resolution image that can hold up to very large print sizes without loss in quality. By shooting at a very shallow depth-of-field (DOF) and then stitching the shots together, you’re exaggerating the shallow DOF.

  • 4
    The photographer says as much, but this doesn't explain why the ground at the same distance as the couple abruptly stops being in focus.
    – Matt Grum
    May 20, 2011 at 12:14

You can always tell if blur was added in photoshop by trying to find the plane of focus. Look at the couple, everything in front of them and to the sides is OOF. To get that kind of effect w/o post processing you'd have to somehow throw the plane of focus in an extremely weird way. Optics don't work like that, even with a technical camera.

  • Optics can work like that, for example extreme field curvature can give you a sphere of focus rather than a plane of focus and cause the areas surrounding a subject to be OOF
    – Matt Grum
    May 20, 2011 at 11:07
  • a similar effect can indeed be achieved with a tilt shift lens. However, as Matt already pointed out this appears to be a "fake" (post-processed) tilt shift effect. May 20, 2011 at 13:20
  • I agree with your assessment.
    – rabbid
    May 20, 2011 at 16:31

This could be achieved without "fake blur" by shooting a series of photos with focus point bracketing and combining them, picking chosen areas focused and chosen out of focus a'la hand-made HDR (except picking focus instead of contrast ).

Is this is the case here... doubtful.

  • That sounds like a whole lotta work that could be done in seconds in Photoshop :)
    – rabbid
    May 20, 2011 at 16:30

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.