alanr0

Does this help? More generally, if we rotate the camera through angle ϕ:

To be precise, I proposed measuring MTF for different illumination wavelengths , not simply for each of the three RGB channels under broad band illumination.  As you point out, the channel ...

I don't know if Rodenstock measure LoCA. One option is to measure MTF for different illumination wavelengths, and find the optimum focus at each wavelength as Jim Kasson does in your link below. Fo ...

Agreed, it could be formally accurate, but not idiomatic. They also say: (1) " Lossless Compressed Raw is recommended when you want to record content in a higher image quality equivalent to uncompressed RAW

What is the basis for your qualified certainty? At the time I posted, the OP Ellis Vener had already explained that he was NOT asking how to locate the entrance pupil.  He wants to know when he can ...

The OP linked the 5DS R , rather than the 5 DS.  However, they both show aliasing , especially in the ACR processed raw images.  The JPG images are more subdued, but still show colour artefacts.

Where does the review mention extinction resolution of the lens? What kind of test target do you use? A 24 Mp APS-C sensor has 4 micron pixel pitch, so sample rate is 250 / mm. Nyquist frequency is ...

The Nyquist-Shannon sampling theorem specifies a minimum sample rate for an arbitrary signal / image to be reconstructed with perfect fidelity. It requires that the bandwidth of the signal is ...

Suppose you have (1) Far subject distance Df (2) Near subject distance Dn (3) Entrance pupil offset from rotation axis Ze

<snip> Is the question you intended: What is the maximum acceptable distance from entrance pupil to tripod rotation axis, given : (1) (Focal length + sensor size) or (horizontal field of view of lens)

ThrillaMozilla's first procedure (1, 2, 3 above) will get you pretty close. A variant on the trial and error scheme is to use a vertical line and a horizontal graduated scale, described in more detail

That's a rather sweeping statement on various counts. Even if the only source of image noise were shot noise, that is insufficient for different sensors to behave identically. Quantum efficiency ...

Emil Martinec's " Noise, Dynamic Range and Bit Depth in Digital SLRs " is a good introduction. Bill Claff's Photons to Photos site is a useful resource. It hosts Martinec's paper, includes Bill's ...

Can you identify the technical shortcomings of the BBC article? I have not yet studied it in detail, but at first glance the section comparing the PQ 10K curve defined in SMPTE ST 2084 with the ...

Both. sRGB tone curve is described in https://en.wikipedia.org/wiki/SRGB HDR10 uses the Perceptual Quantiser tone curve defined by SMPTE as SMPTE ST 2084 The HDR10 encoding covers a wider dynamic ...

<snip> Many (most?) cameras apply tone curves which deviate in some way from the sRGB standard.  For example Nikon D750 , Canon 70D , Pentax K3 . Precision and technical accuracy are part of the ...

<snip> Your posts may get a better reception if you check your facts before resorting to insults and accusations. What the OP said was: Which is a perfectly unobjectionable statement. The OP could ...

As far as I can tell, there is a consensus that in theory noise standard deviation reduces as the square root of the number of identically exposed frames that are averaged. Our dissenting voice ...

Averaging can be equivalent to the sum of exposures if you know how to manage computer arithmetic. One simple approach is to convert the raw data to 32 bit floating point before summing or ...

OK, this is pretty much where we came in. 18% grey on the D850 is solidly in the shot noise limited regime and we can ignore read noise. Electrical signal is proportional to the number of ...