Bokeh ques..

Hello all, my questio is this. I know what bokeh is but how do you acheive it and how do you control it (or can you) Right now I shoot with a S2 and have VERY LITTLE success with it, but have a 40D coming and am looking forward to wasting lots of shots working on technique. Thanks for your answeres in advance

Bokeh drives me nuts.

I'd been away from SLRs for about 12 years and when I logged on to a forum and started reading that term EVERYWHERE, I thought, how out of it am I? Well it is a fairly new use of a Japanese word, according to Wikipedia, so I didn't feel so bad. It has only been in use for a short while.

We used to just call it a "blown out background" or "short depth of field" -- you control it with the aperture setting of the lens. The smaller the number, the wider the aperture, and the less depth of field you will have for a given focal length. So a lens that goes to 200mm at an aperture of 2.8 will give you more of a blurred out background than a lens at 200mm and an aperture of 5.6.

Normally on point and shoots, the aperture is too small for a decently blown out background. You'll have more control with the 40D but you'll also need a lens that is fast enough -- meaning has a wide enough maximum aperture -- to give the effect.


example... 85mm lens, aperture setting 2.8 (I think) -- wide enough to blow out the background but still give a hint of what it was

TheHoff wrote in post #5600797
Bokeh drives me nuts.

I'd been away from SLRs for about 12 years and when I logged on to a forum and started reading that term EVERYWHERE, I thought, how out of it am I? Well it is a fairly new use of a Japanese word, according to Wikipedia, so I didn't feel so bad. It has only been in use for a short while.

We used to just call it a "blown out background" or "short depth of field" -- you control it with the aperture setting of the lens. The smaller the number, the wider the aperture, and the less depth of field you will have for a given focal length. So a lens that goes to 200mm at an aperture of 2.8 will give you more of a blurred out background than a lens at 200mm and an aperture of 5.6.

Normally on point and shoots, the aperture is too small for a decently blown out background. You'll have more control with the 40D but you'll also need a lens that is fast enough -- meaning has a wide enough maximum aperture -- to give the effect.

example... 85mm lens, aperture setting 2.8 (I think) -- wide enough to blow out the background but still give a hint of what it was

It drives me mad when people oooh and ahh over someone's blurry background or they make shots for the express purpose of gaga'ing over the "bokeh" -- subject matter should be more important than how short your depth of field is.

Hoff is right the image should always be about the subject and everything in that image should be supporting the visual statement. To shoot with shallow DoF just for the effect and not for the betterment of the overall image is silly. I use shallow DoF in images to separate the subject from the background because the background is not helping the visual statement. You can also use it to create depth but do it for the right reasons. In the right hands shallow DoF can be a very effective tool.

To clarify a little further, the term 'bokeh' really only refers to the quality of the blurred region, not the degree. Some lenses can make sharp edged little blur disks, or pentagons or even donuts...these all usually distract from the subject which is why they are not desireable. That is bad bokeh.

Good bokeh really is a background that you don't notice. Smooth is typically best. Even lenses that tend to create 'bad' bokeh like the EF 50/1.8 can render a nice background if you blur it enough. Once the blur disks approach the size of the film format their shape and edges start to not matter.

Finally....The reason you struggle to blur the background with a camera like the S2 is that its really small format forces use of very short focal lengths to achieve normal framing compared to larger formats. So a normal portrait on a 5D might be taken at 85mm and f/2.8 (like Hoff's example) but would be taken with the S2 at about 15mm and f/4 which is the closest the S2 can come to the same shot. The degree of background blur for the same subject framing, perspective and background distance will always be much less with a small format digicam.

TheHoff wrote in post #5600797
Bokeh drives me nuts.

I'd been away from SLRs for about 12 years and when I logged on to a forum and started reading that term EVERYWHERE, I thought, how out of it am I? Well it is a fairly new use of a Japanese word, according to Wikipedia, so I didn't feel so bad. It has only been in use for a short while.

We used to just call it a "blown out background" or "short depth of field" -- you control it with the aperture setting of the lens. The smaller the number, the wider the aperture, and the less depth of field you will have for a given focal length. So a lens that goes to 200mm at an aperture of 2.8 will give you more of a blurred out background than a lens at 200mm and an aperture of 5.6.

Normally on point and shoots, the aperture is too small for a decently blown out background. You'll have more control with the 40D but you'll also need a lens that is fast enough -- meaning has a wide enough maximum aperture -- to give the effect.

example... 85mm lens, aperture setting 2.8 (I think) -- wide enough to blow out the background but still give a hint of what it was

It drives me mad when people oooh and ahh over someone's blurry background or they make shots for the express purpose of gaga'ing over the "bokeh" -- subject matter should be more important than how short your depth of field is.

I agree with fact of subject being more important. I shoot my kids and sports and would love to blur the background on the soccer field or wrestling room.

JeffreyG wrote in post #5600977
To clarify a little further, the term 'bokeh' really only refers to the quality of the blurred region, not the degree. Some lenses can make sharp edged little blur disks, or pentagons or even donuts...these all usually distract from the subject which is why they are not desireable. That is bad bokeh.

Good bokeh really is a background that you don't notice. Smooth is typically best. Even lenses that tend to create 'bad' bokeh like the EF 50/1.8 can render a nice background if you blur it enough. Once the blur disks approach the size of the film format their shape and edges start to not matter.

Finally....The reason you struggle to blur the background with a camera like the S2 is that its really small format forces use of very short focal lengths to achieve normal framing compared to larger formats. So a normal portrait on a 5D might be taken at 85mm and f/2.8 (like Hoff's example) but would be taken with the S2 at about 15mm and f/4 which is the closest the S2 can come to the same shot. The degree of background blur for the same subject framing, perspective and background distance will always be much less with a small format digicam.

Boy, I am going to have to read this again, thanks though!!

If you can swing $1,000 for lenses, I'd get the Canon 85 / 1.8 and the 200 / 2.8 primes. If not, post your budget and if you have the kit lens coming as well?

One other thing these guys forgot to mention is distance. Distance from the lens to the subject and distance from the lens to the background.

If you are using a 135mm lens, the subject is 10 feet from you and the background is 75 feet from you. This will give you more background blur than a 35mm lens, 6 feet and 15 feet. It may not be a pleasing bokeh but it will be more blur.

This is long and one tends to lose interest (I did at first).

But when it's read right through, bokeh and its causes become much clearer (anti-bokeh?).

http://www.rickdenney.​com/bokeh_test.htm

rhodesx6,
I have an S2 as well and you can try using the macro mode for normal use. It is just a plaster though. It isn't a full fledged solution.
To get the blurry background you seek, I think you need to zoom as close to the subject as you can, and have the background sufficiently far away from the subject. This is especially hard to do with our small digicams, but it can be done.

trailblazer wrote in post #5601244
rhodesx6,
I have an S2 as well and you can try using the macro mode for normal use. It is just a plaster though. It isn't a full fledged solution.
To get the blurry background you seek, I think you need to zoom as close to the subject as you can, and have the background sufficiently far away from the subject. This is especially hard to do with our small digicams, but it can be done.

Yes I ahve had a LITTLE success with it and in these conditions. I have posted this pic elsewhere but it is probably the best I have......for now (40D coming soon!!!) It is not as as oof as I would like but ......-

Bokeh is indeed the 'quality' of the out of focus area - a purely subjective analysis. Some folks actually like donut shapes in the background. One item that hasn't been mentioned is the DOF calculator. Since the first thing you need to know is what the DOF will be in a given instance, the calculator can be valuable. At least until you understand all that goes into DOF.

Check out the calculator here: http://www.dofmaster.c​om/dofjs.html