[srean]

A question for those who know optics: If the angle of incidence is past the critical angle of red do all of the visible spectrum get reflected without any chromatic effects ?

Are there cameras that have a sensors laid out on a curve matching the expected surface on which the image is in focus ?

I wonder why there are no cameras (apart from astronomical telescopes) that use reflection only for imaging. Such a camera would be too bulky to be practical ?

[zokier]

Mirror objectives do exist for dslrs: https://advancedphototech.wordpress.com/lenses/mirror-mirror...

[wdfx]

I have an old Nikon 500/8 ; gotta be honest, it's not very good.

[buildbot]

Some are not very good, but others are. I currently have 4 different mirror lenses, two are not great but the other two are very good. One of which is an AF mirror lens!

One thing is that they are extremely sensitive to shocks causing mirror misalignment - so if your lens has ever been dropped, it’s probably lower performance than before due to the mirrors being out of wack.

[wdfx]

Mine's from 1974 according to a serial number lookup, so who knows what it's been through in the last 50 years.

[srean]

Thanks for the link. Learned something new.

[PaulHoule]

In the early 2000s I was thinking about a machine vision camera that would use a mirror and a small lens to image a whole room, as seen from a corner. I figured it would take about 50 megapixels to get the performance I wanted and at that time 5 megapixels seemed like a lot.

Today now that is no problem. A few years ago I saw this

https://owllabs.com/products/meeting-owl-3

at work, the fisheye lens on it is more compact than what I had in mind and it has enough pixels to pick out individuals speaking in a conference room.

[RobotToaster]

> Are there cameras that have a sensors laid out on a curve matching the expected surface on which the image is in focus ?

Not a sensor, but some disposable film cameras have a curved film holder to compensate for low quality optics. Some panoramic film cameras do the same.

[Teever]

I had similar thoughts recently because I am working on a catadioptric system for a project at work.

https://www.reddit.com/r/Optics/comments/oimvt0/curved_camer...

https://www.digitalcameraworld.com/news/sonys-new-curved-ima...

It appears that curved sensors maybe exist somewhere in a lab, and have been slightly commericialized, but I didn't see any 'buy now' buttons when I looked.

I didn't dive too deep into it because It's not like I'm going to be changing the sensor in my design at this stage of the game, but it was an idea that a friend suggested when I talked about the limitations of the mirror based system that we're using.

https://techxplore.com/news/2024-07-insect-autonomous-strate...

This link popped up on hackernews a few days ago and I noticed that they were using a mirror in their optical system as well. I haven't had a chance to read beyond that promotional article above so I don't know how they're overcoming the depth of field limitations with this kind of optical set up.

[srean]

Very interesting. All the best for your project.