5D2's 21.1MP sensor and current crop of lenses

[Garion]

With the advent of the full frame 135 format 21.1MP sensor now housed in a cheaper casing and more 'affordable' body, which was also once the exclusive domain of the expensive pro spec 1DsIII, Canon has finally made the 20+ megapixel FF body attainable for the masses, and have set a new benchmark surpassing their former 5D.

So now that 20+ megapixel sensors may be 'de rigeur' in future full frame bodies, are the current crop of Canon lenses able to stand up to such high resolving power? People are saying even L lenses like the EF 17-40mm f4L or EF 24-105mm f4L IS may not be able to resolve sufficient details, especially at the corners and edges.

Whats your take on this?

[CYRN]

hav to ask current 1DsM3 users....

The rest...paper tok onli.

[frostyfrostysnowman]

From a scientific point of view, I would beg to both agree and disagree. Before the age of digital cameras, people stuck to film photography, where the term 'megapixels' were not in existence. The more common choices then were either the standard 35mm or the 4x6, otherwise known as the Medium Format.

At that point in time, I really wouldn't believe the quality of the image would be affected by the lens used on the camera. The job of the lens is to transmit the image from the environment into something the 'sensor' could pick up. In that sense, the resolution of light passing through the lens is infinite, as it is only limited by the size of each photon, or 'bit' of light passing through.

At the end of the day, the 'sensor' on the camera, be it of film/semi-conductor material, has to do the job of resolving whatever comes through the lens. However, I do agree on the part where 20+ MP on a digital camera may have a detrimental effect on the images produced. This is simply because at 20+ MP, EVERY SINGLE FLAW will be seen as clear as day on a picture blown to 100%. Due to this, people might come to the conclusion that 'Oh, the lens is no longer doing it's job properly by resolving images', when it is, in fact, flaws that have existed since the purchase of the lens finally manifests itself on a 20+ MP image.

Image oversharpness, corner sharpness and CA are basically the flaws you would see more on a high resolution image.

[CYRN]

Originally Posted by frostyfrostysnowman From a scientific point of view, In that sense, the resolution of light passing through the lens is infinite, as it is only limited by the size of each photon, or 'bit' of light passing through.

Actually, not true... the resolution of the light are limited at the respective wavelengths... which we are already getting quite close depending on the pixel density of the cam.

that being said... HP cam alreadi can pack >10MP liao... I dun see why FF cannot pack more.

[nikkie]

indeed the high MPs will more easily reveal the under-resolving power of lenses.
however there is now the availability of Carl Zeiss ZE lenses for canon mount (at last!).
5Dmk2 + ZE lenses would be great!

[CYRN]

Originally Posted by nikkie indeed the high MPs will more easily reveal the under-resolving power of lenses. however there is now the availability of Carl Zeiss ZE lenses for canon mount (at last!). 5Dmk2 + ZE lenses would be great!

MF out a little onli and your OOF also easier to notice @ 100%....hahaha.

[frederickykfoo]

Get Carl Zeiss lenses for Canon

http://www.zeiss.com/cln

[frostyfrostysnowman]

Originally Posted by CYRN Actually, not true... the resolution of the light are limited at the respective wavelengths... which we are already getting quite close depending on the pixel density of the cam. that being said... HP cam alreadi can pack >10MP liao... I dun see why FF cannot pack more.

haha it may be limited at different wavelengths but at the end of the day, it shows up as CA doesn't it?

What I was trying to say is that some peeps take the lens as some sort of 'filter', where it would limit the amount of detail coming through the lens.

[CYRN]

Originally Posted by frostyfrostysnowman haha it may be limited at different wavelengths but at the end of the day, it shows up as CA doesn't it? What I was trying to say is that some peeps take the lens as some sort of 'filter', where it would limit the amount of detail coming through the lens.

have... tat you hav to read and understand MTF charts... then you hav to co-relate to the sensor pixel density.

[frostyfrostysnowman]

Originally Posted by CYRN have... tat you hav to read and understand MTF charts... then you hav to co-relate to the sensor pixel density.

haha alright..

[Garion]

Originally Posted by CYRN MF out a little onli and your OOF also easier to notice @ 100%....hahaha.

That is quite true...also same thing wif handshakes...21.1MP FF is no joke....

[fWord]

In the Leica Lens Compendium written by Erwin Puts, he says this:

"The sixties were a period of rapid changes in photography and the criteria of lens evaluation evolved. It was established that good contrast at the limit of the resolving power of the film-emulsion provided better image quality than a high resolving power with lower contrast."

And to extrapolate from what he said elsewhere in the compendium, high contrast is more important than high resolution when it comes to perceived image quality. This is echoed in another article (which can be accessed here- http://www.luminous-landscape.com/tu...lution.shtml):

"The finesse of detail in a photograph is resolution. This resolved detail has a particular degree of visibility, depending on contrast. Resolution and contrast determine image clarity. On the other hand, sharpness is determined by edge definition in the resolved detail, and it is determined by edge contrast."

Take a moment also to read this article on contrast:

http://www.luminous-landscape.com/tu...contrast.shtml

When evaluating a performance of a lens we always talk about 'resolving power' instead of other factors such as contrast and CA (or other aberrations that can have an impact on perceived image sharpness). Assuming that the lenses of the future have a good balance of contrast and resolution and resistance to aberrations and artifacts, then perhaps good image quality can still be achieved on higher resolution sensors.

And while I cannot quote from exact sources, there are an opinionated few who believe that even older, lower resolution sensors have already surpassed the 'resolving power' of a number of lenses, and squeezing more pixels onto a sensor is now simply allowing the magnification of the flaws in that lens. Others argue otherwise, saying that lenses are capable of delivering more resolution than a sensor can extract and resolution is itself lost because of camera shake, motion blur, inaccurate focusing etc.

Ultimately, buy a lens that produces results that look good to your eye. We can worry about resolution limits and all this scientific baloney when we have time to throw to the wind.

[CYRN]

Originally Posted by fWord Ultimately, buy a lens that produces results that look good to your eye. We can worry about resolution limits and all this scientific baloney when we have time to throw to the wind.

Agree... Canon can squeeze 14MP on their G10... I'm sure 50MP+ for FF isn't an issue. At least cam wise.... not sure about PC wise tho.

[marrk]

Originally Posted by frostyfrostysnowman From a scientific point of view, I would beg to both agree and disagree. Before the age of digital cameras, people stuck to film photography, where the term 'megapixels' were not in existence. The more common choices then were either the standard 35mm or the 4x6, otherwise known as the Medium Format. At that point in time, I really wouldn't believe the quality of the image would be affected by the lens used on the camera. The job of the lens is to transmit the image from the environment into something the 'sensor' could pick up. In that sense, the resolution of light passing through the lens is infinite, as it is only limited by the size of each photon, or 'bit' of light passing through. At the end of the day, the 'sensor' on the camera, be it of film/semi-conductor material, has to do the job of resolving whatever comes through the lens. However, I do agree on the part where 20+ MP on a digital camera may have a detrimental effect on the images produced. This is simply because at 20+ MP, EVERY SINGLE FLAW will be seen as clear as day on a picture blown to 100%. Due to this, people might come to the conclusion that 'Oh, the lens is no longer doing it's job properly by resolving images', when it is, in fact, flaws that have existed since the purchase of the lens finally manifests itself on a 20+ MP image. Image oversharpness, corner sharpness and CA are basically the flaws you would see more on a high resolution image.

There's something wrong in your reasoning. In the analog times, shortcomings of lenses were more obvious than they have been in the digital era. When looking at colourpositives through a loupe, edge blurring will be more obvious than in digital photos.

[gymak90]

If I'm not mistaken, some people in this forum, have said that their lenses cannot resolve on their 1Ds3..
To have better quality images, it depends on the resolving power of the lens. I believe 12mp is more than sufficient for most lenses. Be it L or not L. So even if you have a 21.1mp sensor today, you are not guaranteed of a better photo.
On the contrary, because of the higher pixel density, CA, light off fall, distortions that usually pronounced at the corners of the frame become more significant and obvious, since resolving power has increased. While sharpness at the centre of the frame, may or may not improve. So is this really a good thing?

[fWord]

Originally Posted by marrk There's something wrong in your reasoning. In the analog times, shortcomings of lenses were more obvious than they have been in the digital era. When looking at colourpositives through a loupe, edge blurring will be more obvious than in digital photos.

Maybe I am confused but I thought it was the opposite. Sensors, unlike film, need light to strike it at a right angle in order to give optimum imaging performance. When this does not happen (as in the extreme corners of a sensor), problems such as light falloff occur.

[estel]

Originally Posted by frostyfrostysnowman At that point in time, I really wouldn't believe the quality of the image would be affected by the lens used on the camera. The job of the lens is to transmit the image from the environment into something the 'sensor' could pick up. In that sense, the resolution of light passing through the lens is infinite <snip>

if a lens can focus such that all points in its focus distances end up on the focal plane as zero-size tips of the light cones, then what you say is true. But due to various reasons ranging from bad focusing to lenses simply not behaving as theoretical models, lenses can't practically do this. Hence, there is a real thing called a resolution of a lens even if we forgot diffraction.

Recognizing that real lenses do not focus all rays perfectly under even the best of conditions, the circle of confusion of a lens is a characterization of its optical spot. The term circle of least confusion is often used for the smallest optical spot a lens can make ...
http://en.wikipedia.org/wiki/Circle_of_confusion

[An drew]

So now that 20+ megapixel sensors may be 'de rigeur' in future full frame bodies, are the current crop of Canon lenses able to stand up to such high resolving power? People are saying even L lenses like the EF 17-40mm f4L or EF 24-105mm f4L IS may not be able to resolve sufficient details, especially at the corners and edges.

Whats your take on this?[/quote]

Agree. Now we need XL or extra-L lenses. Having seen what a CZ 21 could do, Canon needs to play catchup for it's ultra-wides. Are the new Mk2 16-35L, 14L and 24L up to the job?

[frostyfrostysnowman]

ooops. my bad. hahah. I guess I had too much faith in canon lenses

[ditikolon]

Originally Posted by An drew So now that 20+ megapixel sensors may be 'de rigeur' in future full frame bodies, are the current crop of Canon lenses able to stand up to such high resolving power? People are saying even L lenses like the EF 17-40mm f4L or EF 24-105mm f4L IS may not be able to resolve sufficient details, especially at the corners and edges. Whats your take on this?

Quote: Agree. Now we need XL or extra-L lenses. Having seen what a CZ 21 could do, Canon needs to play catchup for it's ultra-wides. Are the new Mk2 16-35L, 14L and 24L up to the job?

Canon always had to play catch up on its ultrawides. Sad but I think most of you would agree. They've got an excellent (and renowned by its hite color) 70-200 collection, but they could do better with their ultrawides.