Olaf Greve wrote:
> Getting good or bad bokeh seems to be a bit difficult to control, as it's
> largely determined by specific lens characteristics such as the amount and
> shape of the diafragm blades, but there seem to be some other factors as
> well. However, once you've discovered a lens has good bokeh, you can use
> this to your advantage to give your pictures extra punch.
Would this mean that opening up the lens to widest apeture would increase the
bokeh possibilities of that particular lens because the diaphram would then
be round? (Maybe I should burn through some film and find out) :)
> Note that on Acer's page there's an exellent example of very bad bokeh, he
> has even named that picture "badbokehbells" :) This picture was taken with
> the 50/3.5 Macro lens, which seems to have a reputation of having bad bokeh.
> ( http://student.ucr.edu/~siddim01/BADBOKEHBELLS.JPG )
>
> I have also included two links to good bokeh pictures, the first one was
> taken by Giles with the 180/2, and the second one was taken by me with the
> 100/2. You will notice that the backgrounds in these 2 pictures look much
> more pleasing than in Acer's picture.
> ( http://www.taiga.ca/~gallery/subpages/stewart/bride.html )
> ( http://members.xoom.com/olaf_greve/ojg_holl11.html )
Yes, the background in badbokehbells is distracting, to the point of over-
powering the foreground. In Giles' picture, the background is an almost smooth
blur. In yours, there is some texture in the background, but very muted. Your
backgrounds are very much "in the background".
But, I wonder. how much of 'bad bokeh' is the lens, and how much is the fact
that the composition has out of focus bright highlights in it? Or are back-
grounds with light coming through leaves (as in Acer's and my cases) just a
tougher background to tame, requiring better bokeh from the lens to get a
pleasing result?
Thanks for the interesting and educational discussion.
Steve Goss steveg3@xxxxxxxxx Dallas, TX, usa
http://www.flash.net/~steveg3/ <- the images are buried in the MATA stuff,
but they're all done with my OM's. --- Begin Message ---
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Subject: |
Bokeh |
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From: |
Olaf Greve <Ogreve@xxxxxxx> |
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Date: |
Thu, 4 Nov 1999 10:59:41 +0100 |
Hi Steve,
I just read your comment on the ADITL2 page and I noticed that I mistook you
for being Giles Stewart, with whom I've had quite a lengthy off-list
discussion about bokeh, the 180/2 and the 100/2, hence the remarks on the
page :)
Either way, as you specifically asked about how to spot the difference
between good bokeh and bad bokeh, I'm now re-sending the message I sent to
the list yesterday.
Note that on Acer's page there's an exellent example of very bad bokeh, he
has even named that picture "badbokehbells" :) This picture was taken with
the 50/3.5 Macro lens, which seems to have a reputation of having bad bokeh.
I have also included two links to good bokeh pictures, the first one was
taken by Giles with the 180/2, and the second one was taken by me with the
100/2. You will notice that the backgrounds in these 2 pictures look much
more pleasing than in Acer's picture.
Getting good or bad bokeh seems to be a bit difficult to control, as it's
largely determined by specific lens characteristics such as the amount and
shape of the diafragm blades, but there seem to be some other factors as
well. However, once you've discovered a lens has good bokeh, you can use
this to your advantage to give your pictures extra punch. As you will notice
in both Giles' and my picture, the DOF is pretty shallow as we both used a
large aperture setting (I think I used f4, dunno about Giles), this, as
you'll undoubtedly know, causes the background to be blurred. The fact that
these two lenses are good bokeh lenses then take care of blurring the
background in a nice way, on the contrary to the results Acer got (which are
not his fault, but which is purely due to the bad bokeh of the 50/3.5), in
Acer's case the composition was good, yet the picture is a bit ruined
because the bokeh is so harsh. This same effect can indeed be seen a little
bit in the lower left corner of your picture, however, it's only a very
small area (and not the whole background). Now that I'm looking a bit better
at the picture again I notice the bokeh in some more places in the
background to be a bit harsh overall, but it's not too disturbing, besides,
the bokeh in the out of focus parts of the foreground is fine.
Regarding the price of the 180/2 I agree with you, it's also _way_ out of my
league. I got very lucky in finding a 100/2 for some $350, it even had the
original box with it, but there are three tiny scratches on the front
element (which don't seem to affect image quality in a noticable way). It's
one of my most expensive lenses, and I still haven't paid it off, but it was
worth the "investment". A good tip for getting an affordable "good bokeh"
lens is to track down a 135/2.8, this is actually one of the most underrated
Zuikos out there, it is light, fast, sharp, has good contrast and nice
bokeh. Also, it can be used very well with the 2xA as well as with the B-300
(I think that's what it's called) 1.7x TCs for the IS camera's. When used
with these converters, look at the new options you get:
135/2.8 + 2xA -> 270/5.6
135/2.8 + B-300 -> 230/2.8+
135/2.8 + 2xA + B-300 -> 460/5.6+
The latter combination may become a little bit unpractical to use, but
still, compare that against the 400/6.3 or the 500/8...
O.k., for the rest of the bokeh explanation I've included an excerpt of
yesterday's message down below, please let me know if everything's clear, or
if you want more clarification/examples...
Cheers!
Olafo
> I would vote Bokeh because I never worked deliberately with that idea.
> A short description of what Bokeh is would help.
In my own words: Bokeh basically comes down to the way the out of focus
parts of a picture are rendered. This is just a one-line description though,
and probably it's not complete/accurate. Typically a "good bokeh" lens would
nicely isolate the subject from the background by rendering the subject tack
sharp and the background very smoothly blurred, whereas a "bad bokeh" lens
would have a very disturbing background with odd distracting shapes, often
taking the shape of the diafragm. Either way, from what I've understood the
amount of blades of the diafragm is one of the factors that determines the
shape of the out of focus objects...
A while ago a URL was posted on which an article appeared describing some
further factors which apparently determine whether a lens has good or bad
bokeh, so just doing a diafragm blade count will most likely not be
sufficient.
Unfortunaly I have not kept the messages belonging to the bokeh threads that
went around on the list a few months ago, but there were some lenses that
came out as having good bokeh, and at least one that has (reputedly) bad
bokeh.
Bad:
---
-50/3.5 Macro (check: http://student.ucr.edu/~siddim01/BADBOKEHBELLS.JPG )
Good:
----
-180/2 (check Giles' great shot of a bride at:
http://www.taiga.ca/~gallery/subpages/stewart/bride.html for an excellent
example)
-100/2 (check: http://members.xoom.com/olaf_greve/ojg_holl11.html )
-135/2.8
-Probably all the really expensive Zuiko telephoto lenses (180/2.8, 250/2,
350/2.8 - not certain though), especially the ones with the 9-bladed
diafragms???
> Or do we just make images with out of focus backgrounds?
That would be your typical "bokeh" shot :)
> Would some of us be at a disadvantage if we did not have those lenses
> which produce the best bokeh?
Maybe, but some shots on the ADITL2 page clearly show that even with some
50mm lenses you can obtain good bokeh, I noticed that there were two shots
taken with the 50/1.4 which have nice bokeh, a coincidence? Also, the
Monarch shot taken with the 50/1.8 + close-up lenses has lovely bokeh.
I have to admit though that that expensive sucker that I bought recently
(i.e. the 100/2) is certainly delivering value for money, and it's probably
the best "good bokeh" lens I have; I think the 135/2.8 would be my second
best "good bokeh" lens...
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