Such a valuable discussion! As CatMarley points out. See also winterrose.
Add-on points:
1) Lens resolution (resolving power for reproducing detail) and camera-sensor resolution (megapixel count for detail, low-ISO, high dynamic range, and large images and maybe for cropping) are measured independently; display resolution likewise affects the resolution of a digital photo. So, this remark above, "...only the camera can improve the resolution..." needs to account for the two further influences on digital resolution. For more influences, see Mansurov, cited below.
2) Lens resolution depends on lens aperture and light-wave length. As I recall, the latter factor is expressed with a lambda in the system-resolution formula.
3) Every lens is its own special case, even when general numerical arguments are deployed to bounce some lens against some (future, present, past) sensor
4) Which camera? The successor to the D810 could have smaller pixel pitch and could host more receptors; accordingly, its sensor resolution would increase
Apaflo is taking a strong position in his opening sentence about a major current controversy ("...lenses today are as good as the best sensors..."). This controversy affects our spending. I agree with apaflo, after having studied the question. While there are endless public discussions about high megapixel sensors out-performing lenses and the possible need for reformulation of lenses to accommodate (catch up), two major vendors have spoken to the matter. Upleveling my findings from reading of Nikon and Canon publications I have found:
-Nikon clearly and succinctly says Nikon has/have always tried to approach theoretical lens resolution, though it has been overkill, to date, so the implication is: they have largely succeeded, so it is yesterday's war and so:
No worries. Nikon lenses since the 55mm 3.5 appeared, if not before, generally have had resolution that supports denser emerging sensors (bill_de's question). In fact, resolution has long-since become such a cultural value at Nikon that Nikkor lens designers are focused today on natural 3D (See my remark last week on the linearity of DoF in the newest 58mm and 105mm; the realism of this enhanced linearity stands, I presume, in contrast to photographer interventions in DoF continuity with the Nikkor DC lenses.).
-Canon says they are reformulating their lenses to align lenses with sensors and so:
Some worries. Canon's lens reformulation track is stated clearly but not succinctly. I derived my two-word Canon summary above from several published Canon remarks. Canon does explicitly say sensor resolution is today affecting their lens designs. Canon is pushing more resolution to more lenses at less cost, through better materials and manufacturing.
Just remembered, I have kept up a bibliography of the most useful sources I looked at. My references below support my remarks. Note that LenScore is not, IMO, helpful, though I had thought they would be.
Pertinent references assembled by me:
1. Canon, Inc. (2016) “Lenses: Fluorite, aspherical and UD lenses,”
http://cpn.canon-europe.com/content/education/infobank/lenses/fluorite_aspherical_and_ud_lenses.do2. Canon Inc. (2006) “Optical Terminology,” EF Lens Work III: The Eyes of EOS, eighth edition,
http://software.canon-europe.com/files/documents/EF_Lens_Work_Book_10_EN.pdf.
3. Nikon (1979) Nikkor Lenses, Sales Manual.
4. Sato, Haruo and Koichi Ohshita (2016) “Nikkor Future Vision: Lens Design Concepts,”
http://nikkor.com/technology/02.html.
5. LenScore (2016) “High resolution sensors: are lenses up to the task?”
http://www.lenscore.org/.
6. Mansurov, N. (February 17, 2015) “Camera Resolution Explained,”
https://photographylife.com/camera-resolution-explained.
7. Ssymeono (March 6, 2014) “So, it is not the lens, it is the sensor..,”
http://www.uglyhedgehog.com/t-352738-3.html.
8. Dube, B. (May 30, 2015) “Aberrations Theory,”
http://www.photozone.de/aberrationsTheory.
9. “Lens Quality: MTF, Resolution & Contrast,”
http://www.cambridgeincolour.com/tutorials/lens-quality-mtf-resolution.htm.
Apaflo wrote:
Virtually all modern lenses today are as good as the best sensors... at least in the center of the image and at their best fstop. Maybe not in the corners and not wide open (expensive lenses will make the grade there too). But the higher the pixel density the greater the influence of diffraction, and we are getting closer to the day (somewhere between 150 and 250MP) where every lens will be diffraction limited at any useful aperture.
Also note that SS is wrong that only the camera can improve the resolution. What ever the focal length you have, a lens of the same quality but twice the focal length will double the resolution of your images. That is why pro wildlife photogs all have those excessively expensive heavy 600mm f/4 telephotos!
Virtually all modern lenses today are as good as t... (
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