this thread has been off the 1st page for a tad to long - thought i'd bump it. here are some shots from the konica hexanon 40mm f/1.8. somewhere recently i saw it listed as having the worst bokeh of any fast normal lens. i'll let you be the judge.
i have to say i agree that the blur from this lens tends to be less than admirable - though i think the busyness works well with monochrome conversion. the lens is very sharp though with a fair amount of loss of contrast wide open.
these shots were taken on a 4/3 camera. i imagine hexanons would be rather difficult to convert to other formats due to the short flange distance, but i see someone here managed to convert a hexanon 57mm f/1.2.
I like the drawing style of your 40 1.8.
I wonder how that one could be converted to EOS since the aperture ring is in the way of the to be removed mount. Well, somebody on flickr managed it.
Here is the Konica Hexanon AR 57mm 1:1.2.
converted to EF, shots are taken on an EOS 300D
lacksative wrote:
One of the oldies. Not sure if i've posted this before.
Not alternative. Canon EOS 40D with 85mm f/1.2L II near MFD
Notice the "bullseye" on the bokeh.
Pardon for asking a silly question but I notice that the bokeh here is sliced off at the top (flat). I've seen this with the 85L 1.2 and with other lenses with large back elements on DSLRs. It happens with small and large OOFE's and intensifies the further up or down they happen to be in a image. The M8 or M9 doesn't have this issue. Is there any way to mitigate this on a DSLR or we just put up with it? Is it because the internal housing is too small to accommodate light coming through these large back elements?
From my understanding, It's optical vignetting. The Noctilux does it. It can also be caused by the shape of the rear element ala Noct-Nikkor or by something obstructing the rear element like the electrical contacts in the 85L.
Yes, it is some sort of optical vignetting. I would guess from the mirror box of the camera. This is very common with this lens on cameras with such a small mirror box.
The "bullseye" AKA "onion" effect is thought by many to be due to the aspherical element.
Yes it is caused by the size of the exit pupil and mechanical obstructions from the hanging mirror. Nate, I've never seen it in noctilux (or my nokton) shots? I do see the cats eye caused by mechanical vignetting of the lens itself.
Optical vignetting is usally just falloff not usually an abrupt cutoff as it refers to vignetting caused by the glass.
thrice wrote:
Optical vignetting is usally just falloff not usually an abrupt cutoff as it refers to vignetting caused by the glass.
Well, the traditional definition of optical vignetting is not limited to light falloff; it includes the cats eye effect as well: http://toothwalker.org/optics/vignetting.html since it is due to the lens itself.
Also, light falloff can be caused by "natural vignetting". (see same link).
The traditional definition of mechanical vignetting (again, as per the same link) is related to objects in the periphery of the front of the lens (such as lens hoods).
I suppose objects interfering at the other end of the lens ought to be included as well, since they are not a part of the lens itself. So, yeah, lets call this "cut-off" of the highlights mechanical vignetting.
Maybe Toothwalker (author of the site referenced) can comment on this "post-lens mechanical vignetting"; perhaps add it to his already excellent site?
thrice wrote:
Fair enough.
You're right. The Lux still suffers from optical vignetting, but it doesn't cut the top of the circles of confusion off. I was slightly confused; however, I don't think any of this has to do with the mirror box. That shouldn't be anywhere in the optical path if your camera is working right. Clearly the reason the 85L has hightop bokeh is because of some light being obstructed by the electric contacts. Is the 85L's rear element perfectly round? The Noct-Nikkor has a strangely shaped rear element which also causes butchered bokeh on the corners of the frame.
TWoK wrote:
You're right. The Lux still suffers from optical vignetting, but it doesn't cut the top of the circles of confusion off. I was slightly confused; however, I don't think any of this has to do with the mirror box. That shouldn't be anywhere in the optical path if your camera is working right. Clearly the reason the 85L has hightop bokeh is because of some light being obstructed by the electric contacts. Is the 85L's rear element perfectly round? The Noct-Nikkor has a strangely shaped rear element which also causes butchered bokeh on the corners of the frame.
Your explanation doesn't make any sense to me because the electric contacts are not square edged, they are round just like the rear element and you would not expect flat-top bokeh but a round cut off instead. Also it occurs on manual lenses with perfectly round rear elements missing these contacts all together.
I share the view that when the mirror is up (as well as the camera housing on the opposite side) the rear element image circle can be obscured because the housing is too small thus causing this flat-top and flat-bottom bokeh.
My next queston is, why would you pay thousands of dollars on a lens for butchered bokeh on DSLR?
, I only do WO shooting occasionally now.