Luminous Landscape Forum
Equipment & Techniques => Cameras, Lenses and Shooting gear => Topic started by: Playdo on November 28, 2009, 07:10:33 pm
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Hi,
First of all I'd like to say thanks to all those who contributed to my previous thread: http://luminous-landscape.com/forum/index....showtopic=38546 (http://luminous-landscape.com/forum/index.php?showtopic=38546). There was a lot of good information there and I'm hoping that I'll get as good an outcome with this post as there are obviously a lot of knowledgeable people here.
I'd like to know more about perceived sharpness between Canon and Nikon. The majority of Nikon photos that I see have more clarity/contrast to them, especially when viewed on the web. They seem to 'pop' more. This is more evident when looking at photos with a very shallow DOF. I'm not referring to resolving fine details (resolution) but perceived sharpness.
My thoughts on this are:
1. Most Nikon photos that I see have much more vibrant/saturated colours. This itself gives more contrast and can add to perceived sharpness.
2. Nikon lenses may have higher micro-contrast (in general).
3. Nikon may use softer AA filters.
I'm sure there are photographers that have noticed the same thing so I'd be interested to hear your reasonings.
One thing I'm not clear on. If an image is captured with a high micro-contrast lens without an AA filter, providing a sharp, contrasty looking image, can correct use of sharpening techniques in post-processing match it (for a low micro-contrast lens and strong AA filter)?
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There are too many non-camera variables on web-sized JPEGs to be able to distinguish between two 35mm cameras. The resampling and sharpening method become much more important than the sensor. Unless you're doing a comparison without knowing which shot is from each camera before making a judgment, what you're seeing is pure bias.
I ran a test here a while back with web-resolution MFDB and 35mm photos. I had 50 MFDB and 50 35mm shots in the blind test. LL readers were unable to distinguish between them. So comparing two 35mm cameras together is even more difficult. Whatever you're seeing is placebo.
If you're actually running a blind test you can congratulate yourself, as you are an exceptional pixel peeper.
An alternative explanation is that you are seeing "Canon color" which some claim to be able to spot, and applying any preconceived notions to the shots accordingly. Another alternative is that Nikon users like to jack up the Saturation/Vibrance/Sharpening sliders more than Canon shooters smile.gif
Finally, there's a good recent thread about "micro-contrast" and another one started by me on "tonality" here as well - recapping those threads: both words are jedi mind tricks, and are not quantifiable. Don't be fooled by them.
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Hi,
1) Color rendition does not affect sharpness but may affect the perception of it.
2) I don't think so. The term microcontrast seems a bit underdefined to me.
3) Yes AA-filtering may matter. On the other hand I'd suggest that it's effect is overestimated. The choice of AA-filter thickness is to my understanding quite complex and closely related to the fill factor of the sensor. Increasing fill factor reduces aliasing but also resolution.
I guess the effect of the aliasing filter can be reduced by increased sharpening using high amount and small radius.
An ancient comparison of two cameras without/with AA filter can be seen here:
http://www.dpreview.com/reviews/kodakdcs14n/page18.asp (http://www.dpreview.com/reviews/kodakdcs14n/page18.asp)
Today's raw converters are probably better on avoiding color moiré.
A more modern example can be found in this article: http://www.imx.nl/photo/leica/camera/page157/page157.html (http://www.imx.nl/photo/leica/camera/page157/page157.html)
Color moiré can be reduced by desaturating part of the image. Monochrome moiré cannot be eliminated to my best knowledge.
The impression I have is that scientist regard aliasing as an artifact while photographers may under circumstances see it as increased sharpness.
Finally, I suspect that AA-filtering on Canon and Nikon is similar, it seems that they are pretty close in resolution in most test I have seen.
Please keep in mind that there are many factors that are detrimental to sharpness, inexact focusingm camera vibration, lens aberrations and diffraction. In test all these parameters should be controlled in practical shooting this is seldom the case.
Image quality can only be judged at actual pixels or large prints.
Best regards
Erik
Best regards
Erik
Hi,
First of all I'd like to say thanks to all those who contributed to my previous thread: http://luminous-landscape.com/forum/index....showtopic=38546 (http://luminous-landscape.com/forum/index.php?showtopic=38546). There was a lot of good information there and I'm hoping that I'll get as good an outcome with this post as there are obviously a lot of knowledgeable people here.
I'd like to know more about perceived sharpness between Canon and Nikon. The majority of Nikon photos that I see have more clarity/contrast to them, especially when viewed on the web. They seem to 'pop' more. This is more evident when looking at photos with a very shallow DOF. I'm not referring to resolving fine details (resolution) but perceived sharpness.
My thoughts on this are:
1. Most Nikon photos that I see have much more vibrant/saturated colours. This itself gives more contrast and can add to perceived sharpness.
2. Nikon lenses may have higher micro-contrast (in general).
3. Nikon may use softer AA filters.
I'm sure there are photographers that have noticed the same thing so I'd be interested to hear your reasonings.
One thing I'm not clear on. If an image is captured with a high micro-contrast lens without an AA filter, providing a sharp, contrasty looking image, can correct use of sharpening techniques in post-processing match it (for a low micro-contrast lens and strong AA filter)?
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Hi,
You happen to have links to those two discussions?
Agree with your view. I don't know if microcontrast is a Jedi trick but also don't know any definition of it.
Best regards
Erik
There are too many non-camera variables on web-sized JPEGs to be able to distinguish between two 35mm cameras. The resampling and sharpening method become much more important than the sensor. Unless you're doing a comparison without knowing which shot is from each camera before making a judgment, what you're seeing is pure bias.
I ran a test here a while back with web-resolution MFDB and 35mm photos. I had 50 MFDB and 50 35mm shots in the blind test. LL readers were unable to distinguish between them. So comparing two 35mm cameras together is even more difficult. Whatever you're seeing is placebo.
If you're actually running a blind test you can congratulate yourself, as you are an exceptional pixel peeper.
An alternative explanation is that you are seeing "Canon color" which some claim to be able to spot, and applying any preconceived notions to the shots accordingly. Another alternative is that Nikon users like to jack up the Saturation/Vibrance/Sharpening sliders more than Canon shooters smile.gif
Finally, there's a good recent thread about "micro-contrast" and another one started by me on "tonality" here as well - recapping those threads: both words are jedi mind tricks, and are not quantifiable. Don't be fooled by them.
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Hi Feppe. Yeah I wondered how much of it was placebo too so recently I did blind tests and the majority of the time I could confidently notice the difference. Not pixel peeping but I think it's quite evident. I presume that a lot of it is to do with the colours. I think that the vibrancy/saturation seen more in nikon photos adds to the perceived sharpness. Different people with different perception eh. I'm intrigued to know if there's more to it.
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Didn't save the links, searching my topic history will bring up the tonality post, micro-contrast topic might be harder to find as that's a term thrown around a lot here.
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I believe Canon uses a stronger AA filter than does Nikon. In any event, if yuor shooting RAW, it doesn't matter. You can process them anyway you like.
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Please keep in mind that there are many factors that are detrimental to sharpness, inexact focusing
Hi Erik,
This is something else that I have been wondering about. On a lot of forums I hear of people needing to microadjust their Canon lenses. I rarely hear this regarding Nikon. I usually hear that they don't need adjustment. At shallow DOF focus is thin so there isn't much room for error. I don't know much about it myself but I have heard that microadjustment doesn't totally resolve the problem as focus can vary at different distances. If this is the case then a microadjusted lens could easily fall short of critical focus at different distances to the one it was microadjusted to?
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Hi Erik,
This is something else that I have been wondering about. On a lot of forums I hear of people needing to microadjust their Canon lenses. I rarely hear this regarding Nikon. I usually hear that they don't need adjustment. At shallow DOF focus is thin so there isn't much room for error. I don't know much about it myself but I have heard that microadjustment doesn't totally resolve the problem as focus can vary at different distances. If this is the case then a microadjusted lens could easily fall short of critical focus at different distances to the one it was microadjusted to?
What else can you do? You could send the lens to the factory and have it calibrated. After that, if it's not good enough, you use manual focus. I tested my lens' at about 20 feet using the LCD screen test. 70-200IS L, 16-36L, 24-70L all perfect.
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I'd previously got my definition of micro-contrast from the luminous landscape website http://www.luminous-landscape.com/tutorial...-contrast.shtml (http://www.luminous-landscape.com/tutorials/understanding-series/lens-contrast.shtml)
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I'd like to know more about perceived sharpness between Canon and Nikon...
I think you are barking up the wrong tree if you are looking for generalized differences in "sharpness" between two brands like Canon and Nikon. There are great photographers using both brands and producing excellent photography using both, and there is no way to tell which brand was used by looking at the photos. Sure, one lens from brand X might be "sharper" than a similar lens from brand Y... and vice versa, but the the differences are often a matter of degree, cut both ways, and are between lenses that are often both quite good.
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Hi,
There are several aspect to this. One issue is sensor alignment. To achive absolute sharpens Sensor, DSL-mirror, autofocus mirror and the autofocus device msut be aligned within perhaps 10 microns (1/100 of a milimeter) no easy task.
Lately most models have micro adjustment, which probably works. I'd suggest that at least alignment related adjustment would work for all focusing distances.
It's entirely possible that one maker has greater tolerances than an another.
Best regards
Erik
Hi Erik,
This is something else that I have been wondering about. On a lot of forums I hear of people needing to microadjust their Canon lenses. I rarely hear this regarding Nikon. I usually hear that they don't need adjustment. At shallow DOF focus is thin so there isn't much room for error. I don't know much about it myself but I have heard that microadjustment doesn't totally resolve the problem as focus can vary at different distances. If this is the case then a microadjusted lens could easily fall short of critical focus at different distances to the one it was microadjusted to?
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OK,
MTF at low frequencies, right?
Erik
I'd previously got my definition of micro-contrast from the luminous landscape website http://www.luminous-landscape.com/tutorial...-contrast.shtml (http://www.luminous-landscape.com/tutorials/understanding-series/lens-contrast.shtml)
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Hi,
There is a very good article on the Carl Zeiss site describing MTF in visual terms, it's hard to find so I set upo apge with links to it:
http://83.177.178.241/ekr/index.php/photoa...-and-perception (http://83.177.178.241/ekr/index.php/photoarticles/22-a-very-god-article-about-mtf-and-perception)
I'd check out this image: http://www.zeiss.de/C12567A8003B8B6F/Graph...le/Image_02.jpg (http://www.zeiss.de/C12567A8003B8B6F/GraphikTitelIntern/CLN31MTF-KurvenBild2/$File/Image_02.jpg)
And the accompanying article: http://www.smt.zeiss.com/C12567A8003B8B6F/...Kurven_2_en.pdf (http://www.smt.zeiss.com/C12567A8003B8B6F/EmbedTitelIntern/CLN_31_MTF_en/$File/CLN_MTF_Kurven_2_en.pdf)
Best regards
Erik
I'd previously got my definition of micro-contrast from the luminous landscape website http://www.luminous-landscape.com/tutorial...-contrast.shtml (http://www.luminous-landscape.com/tutorials/understanding-series/lens-contrast.shtml)
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Hi,
I'd say that sharpness can only be seen at actual pixels or in large prints. If we see differences in web-size pictures it would be something else. Color characteristics may differ between cameras especially in JPEG. With RAW endless processing options do exist. The same applies to tone curve.
It's well possible that one or another maker would be more successful in reducing flare, which is a major contribution to perceived haziness. Also different vendors take different approaches to noise reduction, but this is mostly a high ISO and JPEG issue.
Best regards
Erik
I think you are barking up the wrong tree if you are looking for generalized differences in "sharpness" between two brands like Canon and Nikon. There are great photographers using both brands and producing excellent photography using both, and there is no way to tell which brand was used by looking at the photos. Sure, one lens from brand X might be "sharper" than a similar lens from brand Y... and vice versa, but the the differences are often a matter of degree, cut both ways, and are between lenses that are often both quite good.
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I'd suggest that at least alignment related adjustment would work for all focusing distances.
Hi Erik,
Are you saying that microadjustment (an in camera function) would work for all focusing distances or do you mean actual calibration (sent in)?
Thanks for the links - very informative. I'll have an in-depth read when I get time.
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Hi Feppe. Yeah I wondered how much of it was placebo too so recently I did blind tests and the majority of the time I could confidently notice the difference. Not pixel peeping but I think it's quite evident. I presume that a lot of it is to do with the colours. I think that the vibrancy/saturation seen more in nikon photos adds to the perceived sharpness. Different people with different perception eh. I'm intrigued to know if there's more to it.
The vibrancy and saturation have more to do with the camera or raw converter settings than the qualities of the raw file produced by the camera. However, there are some differences in color rendering by different sensors as borne out by the DXO tests. To ensure a level playing field, you should use one raw converter and then calibrate the cameras to a neutral setting. For ACR, I would suggest a linear tone curve and the Adobe Standard profile tweaked by using the DNG Profile editor with a Color Checker. The results would look flat, but the playing field would be more equalized.
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My guess is that in camera function is superior to calibration by manufacturer. My guess is also that it may be adequate for all distances.
Please not that both statements are guesses, not without reason but still a guess.
Erik
Hi Erik,
Are you saying that microadjustment (an in camera function) would work for all focusing distances or do you mean actual calibration (sent in)?
Thanks for the links - very informative. I'll have an in-depth read when I get time.
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Finally, I suspect that AA-filtering on Canon and Nikon is similar, it seems that they are pretty close in resolution in most test I have seen.
Here's a quote Graeme Nattress from this thread ... http://luminous-landscape.com/forum/index....showtopic=20367 (http://luminous-landscape.com/forum/index.php?showtopic=20367) which supports this ...
"Optical low pass filters (OLPF's) or Anti Alias filter don't come in different "strengths". The filter works in two passes, each layer splits the light in two either horizontally or vertically, so by combing them together, you get vertical and horizontal filtering. The distance of seperation of the two rays of light is governed by the thickness of that layer, so if you want, (or need to as you don't have square photosites) you can adjust the filter accordingly. You choose the thickness of the filter in relation to the spacing of the photosites on the sensor."
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I just came across this thread: http://www.fredmiranda.com/forum/topic/833110/0 (http://www.fredmiranda.com/forum/topic/833110/0). The OP says it seems "photographers with Nikon cameras and lenses more easily create the unique special look (beautiful sharp, crisp, fresh images with dreamy look, and colors which pop!)". I've heard comments like this by others. This is similar to what I've noticed.
I know that different cameras and lenses give different 'looks'. I also believe that these different looks are better suited to shooting certain subjects.
I'm not talking about resolution here ie. how much detail can be seen. As most of the images that I am viewing are on line so, as mentioned, I'm pretty sure that it is more to do with colour and contrast. Here's examples of what I mean: http://www.flickr.com/photos/tvchicklet/se...57600313161578/ (http://www.flickr.com/photos/tvchicklet/sets/72157600313161578/). All the images taken with the D3 have more colour saturation/vibrancy and contrast and tend to show that sharpness/crispness.
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I just came across this thread: http://www.fredmiranda.com/forum/topic/833110/0 (http://www.fredmiranda.com/forum/topic/833110/0). The OP says it seems "photographers with Nikon cameras and lenses more easily create the unique special look (beautiful sharp, crisp, fresh images with dreamy look, and colors which pop!)". I've heard comments like this by others. This is similar to what I've noticed.
So that's what I've been doing wrong all these years - time to sell my Canon and Mamiya gear!
In all seriousness, nobody is a great photographer due to their gear. Some subject matter requires specialized gear and certain audiences expect specific quality, but in general a camera is a camera, and the greats produce good work whether it's with a Holga or a P65+.
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The OP says it seems "photographers with Nikon cameras and lenses more easily create the unique special look (beautiful sharp, crisp, fresh images with dreamy look, and colors which pop!)". I've heard comments like this by others. This is similar to what I've noticed.
Nonsense. Pure nonsense.
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In all seriousness, nobody is a great photographer due to their gear. Some subject matter requires specialized gear and certain audiences expect specific quality, but in general a camera is a camera, and the greats produce good work whether it's with a Holga or a P65+.
Similar to saying paint is paint, and the greats produce good work whether it's with oil or acrylic. True, they do produce good work, but the results are not the same. For me this isn't about if one piece of gear is better than another it's about understanding certain characteristics of a photograph.
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Nonsense. Pure nonsense.
I don't think it is nonsense, in the sense that there are differences between brands, and people have a subjective appraisal of a given image quality. I am sure there are people who favour Canon over Nikon for various reasons, some real, some not, and maybe most people do not care.
I use Nikon, and they are renowned for a 'contrasty' image. I have a book on macro photography by Paul Harcourt Davies, and I can quite easily recognise the images taken with a Tamron 90mm F2.8 macro lens, and a Nikon 105mm F2.8 AFD lens. The Nikon have more 'snap'. I have owned both lenses, and I also see the same difference in my images, which is why I sold the Tamron. I mention the book as it is something others might have on their bookshelves, hence they can see if they agree or not. Now it so happens that of the lenses that I owned, the Tamron had higher resolution (by a fair margin according to my limited tests). So that means that contrast at the small scale was higher in the Tamron. But on the larger scale, the Tamron produced flatter images. That is not a fault, but a characteristic. I happen to prefer the Nikon look but I am sure others will disagree. I also have a Sigma 400mm F5.6 APO Macro lens, which has good resolution even wide open (on DX), but a slightly flat image quality with a warm cast. The lens is decent, but I do not like the image characteristics, and in this case I think the lens is not up to Nikon (or Canon) standards.
I have not used Canon, so I cannot comment. I also hear people making comments about the Leica and Zeiss look, and I do not discount those comments. The design of a lens is all about compromise, and achieving the desired image quality. And part of that is how the MTF varies with spatial frequency.
If you have access to high end binoculars or spotting scopes, you might be surprised at the differences in contrast and colour rendition. You need to swap between two models to see the differences, as the eye (or rather the brain) quickly adapts and corrects for any colour cast.
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the Tamron had higher resolution (by a fair margin according to my limited tests). So that means that contrast at the small scale was higher in the Tamron. But on the larger scale, the Tamron produced flatter images.
And part of that is how the MTF varies with spatial frequency.
Hi Slough,
So it is mainly due to the proprties of a lens? Could you explain this a bit more as I'd have thought if the 'contrast on the small scale' was higher then the image would have more snap.
Do you notice these properties on Nikon lenses in general? I'm also unsure on what you mean about 'how the MTF varies with spatial frequency'.
Thanks
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I don't think it is nonsense
I never said there were no differences between lenses or sensors or whatnot ... but ...
This statement is pure nonsense ... pure imagination ...
"Nikon cameras and lenses more easily create the unique special look (beautiful sharp, crisp, fresh images with dreamy look, and colors which pop!"
PS - I own, shoot and prefer Nikon DSLRs
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I never said there were no differences between lenses or sensors or whatnot ... but ...
This statement is pure nonsense ... pure imagination ...
"Nikon cameras and lenses more easily create the unique special look (beautiful sharp, crisp, fresh images with dreamy look, and colors which pop!"
PS - I own, shoot and prefer Nikon DSLRs
Okay, fair enough. It is a trifle exaggerated.
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Hi Slough,
So it is mainly due to the proprties of a lens? Could you explain this a bit more as I'd have thought if the 'contrast on the small scale' was higher then the image would have more snap.
Do you notice these properties on Nikon lenses in general? I'm also unsure on what you mean about 'how the MTF varies with spatial frequency'.
Thanks
I am no expert, but I will explain what I understand. But do search for the explanation of MTF on this site by MR, as it is clear and accurate, and will probably help you understand the issues. If you want to see how not to explain MTF, then search for an explanation by someone called Ken Rockwell. The word inept comes to mind.
MTF is a measure of contrast at a given spatial frequency. Simply put it records contrast along a line across the image plane. (I'm ignoring tangential and sagital issues.) If you photograph a series of black and white lines, the image should record an exact copy i.e. perfect black and perfect white, with sharp transitions. But in practice some contrast is lost. The black is not quite black, the white not quite white, and the transition is not sudden, but gradual. The MTF plot represents how close to perfect the contrast is along that line across the image plane. Clearly the one variable here is the spacing of the black and white lines. That is what I mean by spatial frequency. You can plot the MTF for very closely spaced lines, and for widely spaced lines. If you look at MTF plots from manufacturers such as Canon, you see that they usually present MTF curves for two spatial frequencies (and they also provide sagittal and tangential plots, but let's ignore that issue).
Regarding snap, I believe that the snap of an image is due to the contrast at mid spatial frequencies. TV camera lenses used to be optimised for contrast rather than resolution for the obvious reason that TV images had low resolution. Resolution is due to contrast on the very small scale. If you think about it, the resolution limit is where the contrast goes to zero (or at least to the point where you cannot separate lines). So to get high resolution you need to maintain contrast at small scales.
In reality to represent a lens accurately (at a given subject distance) you would need to plot MTF at a whole range of spatial frequencies, but people seem to think that 2 is enough. There are in fact many problems with MTF plots, which most people ignore, preferring to take them as gospel. They tell you nothing about IQ at infinity and close focus, or tendency to flare and ghost, for example.
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Hi,
The issue with flare is important and actually hard to measure. Flare depends on many factors. Antireflex coatings obviously, but also on blackness of mounting tubes in the lens, mirror chamber etc, internal baffling in the lens.
Placebo certainly plays a role.
In my view there is probably not that much of difference between lens families if we shoot raw in a correctly controlled color managed environmeent. On the other hand, correct color is not very usable, it would be flat. Therefore color is always adjusted using an "S" curve enhancing midtone contrast. Most pictures on the net may probably come from in camera JPEGS, with usually something like half a dozen different camera settings producing different colors. Add to this that most images may be in sRGB and most screens are not calibrated. Very few web-viewers handle color profiles correct anyway.
So there are many variables:
- In camera settings, say Nikon 6 Canon 6 that's just 36 combinations
- sRGB/Adobe RGB
- Raw processor if not in Camera JPEGs are used
- Screen calibration and settings (many modern screens are actually close to Adobe RGB, but color is normally assumed to be sRGB)
- Does viewer handle color profiles correctly?
[attachment=18257:ColorSam...anon_20D.jpg]
All this images were made from the same crop from a picture shot by a friend with a Canon 20D. Lightroom tries to reproduce different in camera setting when converting raw. You see that all images are quite different.
Lightroom doesn't have a lot of color profiles for the equipment I use (Sony).
Best regards
Erik
I am no expert, but I will explain what I understand. But do search for the explanation of MTF on this site by MR, as it is clear and accurate, and will probably help you understand the issues. If you want to see how not to explain MTF, then search for an explanation by someone called Ken Rockwell. The word inept comes to mind.
MTF is a measure of contrast at a given spatial frequency. Simply put it records contrast along a line across the image plane. (I'm ignoring tangential and sagital issues.) If you photograph a series of black and white lines, the image should record an exact copy i.e. perfect black and perfect white, with sharp transitions. But in practice some contrast is lost. The black is not quite black, the white not quite white, and the transition is not sudden, but gradual. The MTF plot represents how close to perfect the contrast is along that line across the image plane. Clearly the one variable here is the spacing of the black and white lines. That is what I mean by spatial frequency. You can plot the MTF for very closely spaced lines, and for widely spaced lines. If you look at MTF plots from manufacturers such as Canon, you see that they usually present MTF curves for two spatial frequencies (and they also provide sagittal and tangential plots, but let's ignore that issue).
Regarding snap, I believe that the snap of an image is due to the contrast at mid spatial frequencies. TV camera lenses used to be optimised for contrast rather than resolution for the obvious reason that TV images had low resolution. Resolution is due to contrast on the very small scale. If you think about it, the resolution limit is where the contrast goes to zero (or at least to the point where you cannot separate lines). So to get high resolution you need to maintain contrast at small scales.
In reality to represent a lens accurately (at a given subject distance) you would need to plot MTF at a whole range of spatial frequencies, but people seem to think that 2 is enough. There are in fact many problems with MTF plots, which most people ignore, preferring to take them as gospel. They tell you nothing about IQ at infinity and close focus, or tendency to flare and ghost, for example.
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Hi,
MTF says how contrast is transferred from subject to sensor for items of different size. Large items can be reproduced with full contrast but smaller items loose contrast. The item size is called linear frequency, because the terminology comes from signal processing theory. At small frequencies MTF is essentially 100% at resolution limit it is close to zero. Ideally MTF would fall essentially almost linearly with increasing frequency. MTF is limited by lens aberrations and diffraction. Aberration goes down stopping down and diffraction goes up. Diffraction is a property of light, not optics, so there are no lenses not affected by diffraction (at least not with present technology).
In practice MTF ids often presented as three different frequencies 10/20/40 lp/mm. If we look at an A4 print and compare to old 135 format what we call "full format" now, we would need to enlarge the image 8-times for A4. So:
10 lp/mm -> 20 items/mm on film -> item size 8/20 -> 0.4 mm
10 lp/mm -> 0.4 mm
20 lp/mm -> 0.2 mm
40 lp/mm -> 0.1 mm
Another way to see MTF is how small details will have a certain MTF like 50%, this is the way Imatest works.
Why don't you check this? http://www.normankoren.com/Tutorials/MTF1A.html (http://www.normankoren.com/Tutorials/MTF1A.html)
Best regards
Erik
Hi Slough,
So it is mainly due to the proprties of a lens? Could you explain this a bit more as I'd have thought if the 'contrast on the small scale' was higher then the image would have more snap.
Do you notice these properties on Nikon lenses in general? I'm also unsure on what you mean about 'how the MTF varies with spatial frequency'.
Thanks
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That is a good point about JPG. As stated, each manufacturer will apply tone curves to the RAW data when creating a JPG image. And of coruse many people use settings such as enhanced saturation. That means that each camera will have its own look according to the users preferences, and the camera makers choices. Peronally I shoot RAW with neutral settings, as do many here I am sure.
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Hi,
Thanks very much for the info. So, correct me if I'm wrong;
1. The 'snap' is partly due to contrast on the small scale (referred to as micro-contrast?) at mid-spacial frequencies.
2. At capture this is largely a property of the lens.
3. In post processing, sharpening technique (ie unsharp mask etc) mimics this kind of contrast.
4. A tonal curve controls the overall contrast of an image.
Erik: As mentioned previously I really notice it in the shots taken by the D3 http://www.flickr.com/photos/tvchicklet/se...57600313161578/ (http://www.flickr.com/photos/tvchicklet/se...57600313161578/). I also see it a lot more in D700 shots. Recently I think that Nikon's increased the vibrancy/saturation in some of their presets (even if shooting RAW I think people are post processing to a similar style of these presets).
What I wasn't sure of is if the crispness was due to this 'overall' contrast (due to the increased vibrancy/saturation) or whether it was due to smaller contrast (a property of the lens/sharpening technique/pixel density).
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The 'snap' is partly due to contrast on the small scale (referred to as micro-contrast?) at mid-spacial frequencies.
Sure ... but let's be clear ... there is no generalized and statistically significant difference between "Nikon" and "Canon" in this regard. Any difference you think you can divine from examining images is likely the result of differences in RAW processing and not the result of differences between "Nikon" and "Canon" optics.
I promise you that you (and others) would fail a blind image test based on your hypothesis.
You seem convinced of something that is a illusory, and the sooner you disabuse yourself of this shibboleth, the better.
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Sure ... but let's be clear ... there is no generalized and statistically significant difference between "Nikon" and "Canon" in this regard. Any difference you think you can divine from examining images is likely the result of differences in RAW processing and not the result of differences between "Nikon" and "Canon" optics.
I take it that you own/use both Nikon and Canon, and that you have performed these tests? As I've said before, not having used Canon, I cannot comment.
As I said, I see very real differences between the rendition of the Tamron 90mm F2.8 macro lens, and Nikon micro lenses, and also some of my old Nikon lenses have less 'snap'. I once owned the 28mm-105mm AFD zoom which is very popular, but I never liked the 'flat' and rather cool rendition. I even see this in online samples, which is curious as online JPGs are small, and processed/manipulated by RAW conversion software (sometimes in camera). Improved coatings, use of ED glass, and better designs will change the IQ.
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I take it that you own/use both Nikon and Canon, and that you have performed these tests? As I've said before, not having used Canon, I cannot comment.
As I said, I see very real differences between the rendition of the Tamron 90mm F2.8 macro lens, and Nikon micro lenses, and also some of my old Nikon lenses have less 'snap'. I once owned the 28mm-105mm AFD zoom which is very popular, but I never liked the 'flat' and rather cool rendition. I even see this in online samples, which is curious as online JPGs are small, and processed/manipulated by RAW conversion software (sometimes in camera). Improved coatings, use of ED glass, and better designs will change the IQ.
Ok, fair enough. I have not performed extensive tests.
BUT ... I have seen enough images shot with enough lenses and cameras over the last 30 years to know in my gut that there is nothing shared across ALL nikon equipment that is somehow recognizably "nikon" and that it is this ephemeral aspect of the equipment that makes it "better" at producing "good" images than any other serious system.
There are differences between lenses and cameras ... but I'll stick by my 'nonsense' characterization until I see some evidence of this 'shared' aspect that cuts across all Nikon-branded equipment.
I'm not making the extraordinary claim that there is some Nikon magic that is better than the Canon magic ... I'm just the skeptic.
Like I said, there are differences is equipment ... but to then infer from that that 'Nikon' is better than 'Canon' simply because not all cameras and lenses are alike is nonsense.
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there is nothing shared across ALL nikon equipment that is somehow recognizably "nikon"
No one mentioned it being across all Nikon equipment. I stated that I see something in the majority of Nikon photos that I see and then went on to say I've noticed it a lot in D3 and D700 shots. I don't appreciate you insulting my perception, or others'.
infer from that that 'Nikon' is better than 'Canon'
Was it mentioned/inferred that one was better than another? (that's a rhetorical question by the way).
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I don't appreciate you insulting my perception, or others'.
Get over it ... I'm sorry you feel insulted ... I'm just trying to be direct with you. Most people are too polite to tell you when you are full of it.
Was it mentioned/inferred that one was better than another? (that's a rhetorical question by the way).
rhetorical, smergorical ... You wrote this:
"... 'photographers with Nikon cameras and lenses more easily create the unique special look (beautiful sharp, crisp, fresh images with dreamy look, and colors which pop!)'. I've heard comments like this by others. This is similar to what I've noticed."
I said I thought this was nonsense and I stand by that.
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Hi,
In essential, yes sharpening affects mid spatial frequencies. I agree with your interpretation by and large.
Regarding color rendition my guess is that Nikon may have more vibrant colors. It may also be that at least some Nikon models can have sharper color filter grid array characteristics than corresponding Canon models, but I would not overemphasize these differences.
The effect of sharpening would be not visible in small pictures (like anything that fits on the computer screen). HD video is just two Megapixels ;-)
Best regards
Erik
Hi,
Thanks very much for the info. So, correct me if I'm wrong;
1. The 'snap' is partly due to contrast on the small scale (referred to as micro-contrast?) at mid-spacial frequencies.
2. At capture this is largely a property of the lens.
3. In post processing, sharpening technique (ie unsharp mask etc) mimics this kind of contrast.
4. A tonal curve controls the overall contrast of an image.
Erik: As mentioned previously I really notice it in the shots taken by the D3 http://www.flickr.com/photos/tvchicklet/se...57600313161578/ (http://www.flickr.com/photos/tvchicklet/se...57600313161578/). I also see it a lot more in D700 shots. Recently I think that Nikon's increased the vibrancy/saturation in some of their presets (even if shooting RAW I think people are post processing to a similar style of these presets).
What I wasn't sure of is if the crispness was due to this 'overall' contrast (due to the increased vibrancy/saturation) or whether it was due to smaller contrast (a property of the lens/sharpening technique/pixel density).
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I'm just trying to be direct with you. Most people are too polite to tell you when you are full of it.
I'll help you out then Jeremy; you're full of it.
rhetorical, smergorical ... You wrote this:
"... 'photographers with Nikon cameras and lenses more easily create the unique special look (beautiful sharp, crisp, fresh images with dreamy look, and colors which pop!)'. I've heard comments like this by others. This is similar to what I've noticed."
I said I thought this was nonsense and I stand by that.
It was a reference to another post and the opinions of some other photographers. I was referring to the 'crisp and colours which pop'; two factors that I see quite evidently. I know you can't believe it Jeremy but your perception/differentiation of imagery isn't universal. 30 years eh? You'd think you'd know that certain equipment would more easily produce certain results by now. Anyway, just letting you know, I'll be sure to skip over your future posts.
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Thank you for the info Eric
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You'd think you'd know that certain equipment would more easily produce certain results by now.
Oh, I've become familiar with lots of different pieces of equipment over the years ... enough to know that there is nothing 'shared' across 'Nikon' equipment that would explain this illusory 'Nikon Pop'.
Anyway, just letting you know, I'll be sure to skip over your future posts.
Sure you will ... everyone always says that ... and they never do ... so I'll see you around!
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Ok, fair enough. I have not performed extensive tests.
BUT ... I have seen enough images shot with enough lenses and cameras over the last 30 years to know in my gut that there is nothing shared across ALL nikon equipment that is somehow recognizably "nikon" and that it is this ephemeral aspect of the equipment that makes it "better" at producing "good" images than any other serious system.
There are differences between lenses and cameras ... but I'll stick by my 'nonsense' characterization until I see some evidence of this 'shared' aspect that cuts across all Nikon-branded equipment.
I'm not making the extraordinary claim that there is some Nikon magic that is better than the Canon magic ... I'm just the skeptic.
Like I said, there are differences is equipment ... but to then infer from that that 'Nikon' is better than 'Canon' simply because not all cameras and lenses are alike is nonsense.
There's a few points in your post.
Regarding the claim that Nikon has a certain magic that Canon doesn't, and hence they are better, I think most of us will agree that that is not true. And as you have said, post processing and in camera settings will make a huge difference to the final output. There is also a variation within each manufacturers lenses, some gems, some dogs, some in between.
Regarding the notion that in general manufacturers have their own style, that is hard to prove, or disprove. I use neither Zeiss nor Leica, but people who uses those brands often comment that there is a consistent difference in rendition betwen the two and also between Leica and Nikon. Is that bullshit based on "my brand is better than your brand"? Perhaps, but I hear it from some sane people. I have no direct experience of those brands so cannot comment directly. However, Canon use Flourite in many lenses, and that has particular transmission characteristics including of course a colour cast that must be balanced by careful choice of the other glass used, and coatings. Nikon will also have their own glass, with its characteristics, and their own coatings. Will that influence the result? I would expect so. To a noticeable degree? It is possible. Will some manufacturers choose glass and coatings to for example favour contrast at mid spatial frequencies? Again, it is possible.
As I have said a few times, I see obvious differences between two third party lenses I have owned, and the Nikon ones I own. Are these consistent trends? I don't know. (It is one reason I prefer to avoid third party lenses.)
But I do recall one good example that optical equipment can have a consistent 'feel' to the image. If you look at some of the old Soviet binoculars and monoculars, you will see images with a strong yellow cast, due no doubt to the choice of coatings and glass. (I suspect they were single coated with MgFl.) That is of course an extreme example, but it does show that a lens is not just transparent glass with a flat transmission spectrum in the visible wavelengths. The truth is that optical designers have a tough job to correct for the various aberrations and maintain the required colour rendition and contrast levels.
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Regarding the little squabble that has erupted, unfortunately this issue is something that is not easily characterised. From time to time I read people commenting on Nikon's contrasty rendering. I've even read comments from people trained in optical design. Some dislike it. Others don't. The problem here is that none of us it seems to have extensive experience of using a number of systems e.g. Leica and Nikon, or Nikon and Canon, and hence we are not qualified to make a definitive subjective comment.
By the way, people often tell me they see obvious colour casts when using particular high end binoculars. I don't and have to work very hard to figure out the colour cast, which I can do with practice. And yet I see chromatic aberration that most other people miss. Some of this issue is possibly about educating the eye (i.e. the brain) to perceive something that exists, but which is often ignored. The eye (i.e. brain) readily accommodates itself to the current situation.
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Out of curiosity I picked up one of my old books, by someone called Boyd Norton. He used Nikon and Leica. Almost all the time I can pick which photos are taken with Nikon and which not. The Nikon ones have a noticeably more contrasty rendition. Notice I don't say better. Just different. Choice of film seems not to explain this. The book is 15 years old though.
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Thanks Slough