Originally posted by stevebrot Stack thickness and exit pupil diameter are not particularly important for SLR lenses.
Steve
It affects the performance on modern DSLR. The refractive index and optical thickness affects performance. Coma, color fringing, sharpness.
Also one of the many reason some cine glass makers have started redesigning their vintage lenses for Digital cameras
---------- Post added 09-02-20 at 10:12 AM ----------
Originally posted by leekil I believe there have been articles about sensor stack thickness and lenses on the lens rentals blog in the past?
Yes, true. Their experiments were completely scientific in nature considering the graphs and readings they posted
---------- Post added 09-02-20 at 10:14 AM ----------
Originally posted by UncleVanya If you cite the source maybe we can give more context to our answers. I think I've read something about how this impacts mirrorless designs but I can't recall the details.
I read the article on lens rentals, this guy testing lenses in a lab. If you want I can post the links to his articles
---------- Post added 09-02-20 at 10:17 AM ----------
Originally posted by stevebrot Yep...The matter is specific to designed-for-mirrorless lenses and is somewhat controversial even in that context. It was discussed in detail here several years ago. There was a blogger who was frequently referenced, but my memory is that example images showing poor performance were hard to come by.
Steve
It affects DSLRs too. And the difficulty in designing for digital sensors. Considering the fact that, the glass infront of the sensor contain multiple filters, it, uv. It affects mostly wide angle, super fast, and with exit pupils less than 70mm
---------- Post added 09-02-20 at 10:39 AM ----------
Originally posted by PJ1 It can't be much of an issue or third party lens manufacturers would have a problem. Samyang, Sigma, Tamron and others can offer a range of mounts but I don't think they adapt the optics to specific systems.
Actually it's a really big issue. The recently released CV 50mm f1.2 in two different mounts, perform different from eachother. The FE mount version performs poorly than the m mount version on other mirror less cameras. Leicas version was optimised for a stack thickness of 1mm and performs better on fuji x mount and canon RF mount. Because both of them have stack thickness equal to 2 mm.
Some of my friends, who are professionals in the cinema industry told me about the mount variations.
---------- Post added 09-02-20 at 10:42 AM ----------
Originally posted by Rondec I think @pinholecam shoots with one of the Sony mirrorless (along with a K-1) and mentioned that he had to change the sensor stack in order to adapt certain lenses to his Sony camera. As I recall the issue is primarily seen with wide angels and a short registration distance, but I am no master of the MILC universe.
No not the registration distance, I think he meant the exit pupil distance from sensor. Anything below or near 70 will not perform good on Sony and m4/3 cameras. The super takumar 50mm f1.4 Has exit pupil distance of 70.xx mm
---------- Post added 09-02-20 at 10:47 AM ----------
Originally posted by pentaxus My understanding is that sensor stack thickness affects mirrorless cameras using wide angle lenses designed for film.
Not just mirrorless, DSLRS too. Both use the same sensor. It comes down to stack thickness and f stops below 2
---------- Post added 09-02-20 at 10:53 AM ----------
Originally posted by UncleVanya What appears to be the case is that this is mostly a non issue when using adapted SLR or DSLR lenses on Sony. It is more of an issue with Leica M lenses on m4/3. Basically if the sensor glass thickness is significantly different, there can be an optical effect.
Sensor Stack Thickness: When Does It Matter?
Oh and the closer the exit pupil to the sensor, the more impact this has. Slr wide angles with their retrofocal designs are typically less impacted than rangefinder wide angles.
The article also states that it affects lenses with exit pupil closer than 70mm