PeterPrism
Member
This is a Jpg File done with my beautiful, loved and hated X-Pro1 & 18mm original fujifilm at:
f 3.6 - 1/160 sec - 800 ISO.(images resized due the site limitation).
This pic shows a strange (very ugly IMO) bokeh (see the enlargement below)
Can you please explain in optical terms:
(1) why it is present,
(2) what is it,
(3) if it is only a result of a digital camera or can be obtained also in an analog camera
(4) if it is a problem referred to the lens or to the sensor,
(5) if it is referred to the lens: do you think the zoom 18 --> 55 has the same problem?
(6) if it is referred to the lens: what do you think if I replace 18 & 35 for a new 23?
(7) how to prevent a future similar bad result ? [(obviously, don't tell me to reduce F-stop, I wish use the bokeh feature taking advantage of this fast (f 2) aperture lens)]
Thanks to you all X-Friends!
Peter
f 3.6 - 1/160 sec - 800 ISO.(images resized due the site limitation).
This pic shows a strange (very ugly IMO) bokeh (see the enlargement below)
Can you please explain in optical terms:
(1) why it is present,
(2) what is it,
(3) if it is only a result of a digital camera or can be obtained also in an analog camera
(4) if it is a problem referred to the lens or to the sensor,
(5) if it is referred to the lens: do you think the zoom 18 --> 55 has the same problem?
(6) if it is referred to the lens: what do you think if I replace 18 & 35 for a new 23?
(7) how to prevent a future similar bad result ? [(obviously, don't tell me to reduce F-stop, I wish use the bokeh feature taking advantage of this fast (f 2) aperture lens)]
Thanks to you all X-Friends!
Peter
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wogg
Established
To my eyes, the lens has not horrible OOF rendering there, not great either. Mostly it's just exaggerated and exacerbated by unfortunate lighting coincidence (blowout and highlight at extreme corner).
I don't think there's any blame on the hardware here. It's just tough lighting conditions.
I don't think there's any blame on the hardware here. It's just tough lighting conditions.
PeterPrism
Member
Thanks; do you think that an analog camera in the same situation will have the same result?
jim_jm
Well-known
I've had similar results with film, but I suspect the effect may be unpredictable based on the range of brightness in the scene and the type of subject matter.
In your example, the difference in brightness was just too much, if you wanted to keep the foreground correctly exposed. Digital also has limitations, you just need to be aware of them at the time you are composing your shot. Landscape photographers routinely use split-contrast filters to reduce the brightness of the sky so they give adequate exposure to the darker foreground. Post-processing can sometimes help, but it's always best to recognize these issues and correct for them at the time you're shooting.
Also, this area is in the extreme corner of your frame and most lenses achieve best performance in the center, especially if you are shooting wide-open. This scene would not be the best to use if you are trying to determine the bokeh characteristics of a lens.
This was shot on Provia 400. Slide film is generally less tolerant of under/overexposure than negative film, color or B/W. I was in the shade and there was a parking lot and white building behind me in bright sunlight. I like how the tree looks like it's on fire - some of the distortion is due to the mirrors but the bright background is way beyond the range the film can handle since I metered for the shade and didn't want to lose shadow detail.
In your example, the difference in brightness was just too much, if you wanted to keep the foreground correctly exposed. Digital also has limitations, you just need to be aware of them at the time you are composing your shot. Landscape photographers routinely use split-contrast filters to reduce the brightness of the sky so they give adequate exposure to the darker foreground. Post-processing can sometimes help, but it's always best to recognize these issues and correct for them at the time you're shooting.
Also, this area is in the extreme corner of your frame and most lenses achieve best performance in the center, especially if you are shooting wide-open. This scene would not be the best to use if you are trying to determine the bokeh characteristics of a lens.
This was shot on Provia 400. Slide film is generally less tolerant of under/overexposure than negative film, color or B/W. I was in the shade and there was a parking lot and white building behind me in bright sunlight. I like how the tree looks like it's on fire - some of the distortion is due to the mirrors but the bright background is way beyond the range the film can handle since I metered for the shade and didn't want to lose shadow detail.
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Scrambler
Well-known
Google for Zeiss on bokeh. They say attractive bokeh comes from spherical aberration and then you get a choice between good in front of focus or behind but not both. A well corrected lens shows an even disk for out- of-focus point light sources. The strong contrast in your photo is making the filtered light appear as overlapping disks. Your lens is well corrected. You can't have everything which is why Zeiss has a Planar (well corrected, pin sharp) and Sonnar (great bokeh behind focus) 50mm lenses.
Bokeh is a Japanese word that talks about senior citizens who have dementia. Not something in our view to be emulated. Had a friend into bokeh and he finally switched to lace doilies and was much happier.
PeterPrism
Member
Thanks to you all for the contribution.
Cheers, Peter
Cheers, Peter
icebear
Veteran
Without blaming optics (and lighting conditions):
Have you inspected the raw file, rather than looking at the jpgs?
All auto/standard processing will introduce artifacts that don't necessarly make area out of focus look natural.
First of all - sharpening needs to be turned off
.
Have you inspected the raw file, rather than looking at the jpgs?
All auto/standard processing will introduce artifacts that don't necessarly make area out of focus look natural.
First of all - sharpening needs to be turned off
.
willie_901
Veteran
Speculation about how this lens would look on on a film camera is pointless.
The Fujinon 18/2 has significant barrel distortion. Barrel distortion correction parameters are read from the lens' on-board firmware. With a pure analog work-flow, these corrections would require a custom designed enlarger lens to cancel the barrel distortion. With a hybrid workflow the scanned image would require post-processing software with correction parameters in the range demanded by this lens.
The Fujinon 18/2 has significant barrel distortion. Barrel distortion correction parameters are read from the lens' on-board firmware. With a pure analog work-flow, these corrections would require a custom designed enlarger lens to cancel the barrel distortion. With a hybrid workflow the scanned image would require post-processing software with correction parameters in the range demanded by this lens.
boomguy57
Well-known
As far as I know "bokeh" refers to the quality of the out of focus rendering, and isn't the term for things out of focus themselves. It am I wrong on this?
In response to the OP, OOF rendering has to do with DOF, which is relative to the frame/sensor size. So f/3.6 on APS-C isn't really f/3.6 as we think of it in classic 35mm-film terms. It's a mathematical formula of some kind.
I'm sure someone else can be more detailed.
In response to the OP, OOF rendering has to do with DOF, which is relative to the frame/sensor size. So f/3.6 on APS-C isn't really f/3.6 as we think of it in classic 35mm-film terms. It's a mathematical formula of some kind.
I'm sure someone else can be more detailed.