A question about Contax Digital

[raj]

Many a times in this forum when discussing different lenses there is always the mention of good and bad out of focus rendering of different brands. Can someone point out a site or provide pictures where this can be seen.

A picture with GOOD and a picture with BAD out of focus area.

 

[mike_nunan]

Hi Raj,

Here's an ex&le of bad bokeh:

http://www.photo.net/photodb/image-display?photo_id=465198&size=lg (image)

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=002mUO (discussion)

And another, with comprehensive set of links that provide all the info you should ever need on the subject:

http://medfmt.8k.com/mf/bokeh.html

Finally, a technical discussion detailing the optical causes of bokeh:

http://luminous-landscape.com/essays/bokeh.shtml


I would be wary of accepting any statements ascribing universally good or bad bokeh characteristics to any one manufacturer's entire lens range. Although Zeiss and especially Leitz are widely regarded as producing lenses with good bokeh, there are exceptions. E.g., not everybody likes the bokeh of the 50mm f/1.4 Planar (maybe because it has only five aperture blades in the AE version - I can't say, I like mine!) and the really bad bokeh ex&le above comes from a Leitz 180mm APO lens that probably cost more than my entire Contax system. Regarding Fujinons, I saw a shot yesterday from a Fuji GX680. Not sure which lens was used but I would class the bokeh as "acceptable". Nothing to write home about, and could probably become objectionable with the wrong subject matter (back-lit foliage always seems to bring out the worst in lenses with bokeh problems) but in this particular shot it was not a problem, even though the photographer had used the tilt movement to throw part of the main subject out of focus as well as the background. Thanks for the alert though Austin, if nothing else it's cooled me off regarding the GX680 which was looking like the next big purchase, even though I definitely can't afford it at the moment.

 

[rico1]

Ah, the backlit-foliage-bokeh-generator! I know it well:

penny2.jpg

Not the prettiest bokek, what with the distinctly-rendered pentagonal aperture (Canon EF fisheye). Here, I'm attempting to incorporate it into the composition.

One important feature of a full-frame sensor like the dearly-departed N Digital is having OOF possibilities at all - ugly bokeh, or not. The P&S digital with its tiny sensor has enormous, inescapable DOF. Sharpness gets dull after a while.

.

 

[afranklin]

Hi Mike,

> I would be wary of accepting any statements ascribing universally good > or bad bokeh characteristics to any one manufacturer's entire lens > range.

Hum. I agree to a point...but...as I stated, all the Fuji MF lenses I've used (and have seen images from) that have OOF areas that one would consider "bokeh" have had bad bokeh, IMO. So, if I'm only stating my personal experience. I agree that claiming that ALL Leica lenses have good bokeh or ALL Fuji lenses have bad bokeh would be something to not take entirely at face value.

> E.g., not > everybody likes the bokeh of the 50mm f/1.4 Planar (maybe because it > has only five aperture blades in the AE version

But...at full aperture, the aperture blades don't enter into the picture, so you can't really judge the quality of a lenses bokeh without having a bit more information (like at what f-stop the picture was taken...).

Regards,

Austin

 

[mike_nunan]

Hi Rico,

Was that the 15mm f/2.8 EF? If so that's a lot nice than the bokeh produced by my Sigma equivalent (there had to be a downside to buying a lens that cost half the price of the Canon I guess!) Personally I don't have a problem with pentagonal blur regions, I think they look kinda classic.

Hi Austin,

> I agree that claiming that ALL Leica lenses have good bokeh or ALL Fuji lenses have bad bokeh would be something to not take entirely at face value.

Yeah I knew that wasn't what you were really trying to say, I was just pointing it out in case anyone else was taking things literally. Reminds me of conversations among racing drivers, where you hear claims that a certain corner or kink can be taken with the foot flat to the floor... a lot of novices learn to their cost that there's a certain "reality adjustment factor" that needs to be applied when listening to that sort of advice!

> At full aperture, the aperture blades don't enter into the picture

True, true. And I guess the bokeh characteristics can vary depending upon aperture, as the level of spherical aberation varies. Ditto the subject distance (where "subject" in this case means the bright highlight in the background). I guess the best approach is to do a quick test before buying a lens. It's not a hard thing to assess, given that a few handheld shots will reveal most of
what you need to know.

TTFN

-= mike =-