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Peter De Smidt
19-Mar-2021, 19:19
https://petapixel.com/2019/07/05/goodbye-aberration-physicist-solves-2000-year-old-optical-problem/?fbclid=IwAR2TheeqVUvNwHxcITkQUj4wtSyynBBlyvtA31bnJVHRoNBTzmXJdyUI5GE

Tin Can
20-Mar-2021, 05:48
Yes, but I prefer soft corners.

I find sharp images to the very edge of rectangles harsh.

Most likely, as I grew up on old tiny TV with round corners.

I recall being in a room full of people watching the only TV in the area, of The Beatles on B&W 8" console like below.

Nobody was allowed to get close or block viewing, so it was really odd, bad sound too. Smelly old people in control.

Perhaps my first TV screen ever. The next TV memory was JFK assassination.

https://live.staticflickr.com/65535/51055144276_143c3b59e3_c.jpg (https://flic.kr/p/2kMyXEd)Old TV (https://flic.kr/p/2kMyXEd) by TIN CAN COLLEGE (https://www.flickr.com/photos/tincancollege/), on Flickr

Conrad . Marvin
20-Mar-2021, 06:10
Did you ever take pictures of the TV screen? 1/25 second or you didn’t get the whole screen. I took the lunar landing with the banner “ Live from the moon” across the top. Horrible resolution, but the sound was better than my 1st digital TV.

Conrad . Marvin
20-Mar-2021, 06:11
PS, Love the TV! Looks like a face .

Exploring Large Format
20-Mar-2021, 06:58
Yes, but I prefer soft corners.

I find sharp images to the very edge of rectangles harsh.

Most likely, as I grew up on old tiny TV with round corners.

I recall being in a room full of people watching the only TV in the area, of The Beatles on B&W 8" console like below.

Nobody was allowed to get close or block viewing, so it was really odd, bad sound too. Smelly old people in control.

Perhaps my first TV screen ever. The next TV memory was JFK assassination.

https://live.staticflickr.com/65535/51055144276_143c3b59e3_c.jpg (https://flic.kr/p/2kMyXEd)Old TV (https://flic.kr/p/2kMyXEd) by TIN CAN COLLEGE (https://www.flickr.com/photos/tincancollege/), on FlickrThanks for the memories! I remember when the Beatles were on Ed Sullivan, and my older sister had to wash her hair. She asked me to let her know when they came on. I told her, and she came running and screaming into the living room, hair dripping wet. On the TV with the round corners and terrible reception of 4 stations. Later, yes, the moon landing.

Sent from my SM-G981V using Tapatalk

John Layton
20-Mar-2021, 08:04
"Looks like a face." ...a spider face (spiders have eight eyes).

reddesert
20-Mar-2021, 12:43
Photography blogs write about optics very badly.

These papers are a clever solution to an analytical mathematical problem, and maybe some derivative of the technique will trickle into lens design methods. But the solutions are only of mathematical interest at the moment. For example, in the first paper, they calculate lenses of complex shapes that correct spherical aberration perfectly, but only calculate on-axis.

The actual task of the optical designer is to balance several constraints such as on-axis, off-axis aberrations, curvature of field, ease of manufacture, error budget, etc. Allowing non-spherical lens surface shapes helps meet some of these constraints (more complex recent photographic lenses often have a few aspherical surfaces). But, perfectly meeting one constraint without regard to any others is not how real lenses are designed. It's interesting that it can be done, but theoretical at the moment.

Joe O'Hara
21-Mar-2021, 15:18
Tin Can: That looks like a real antique-- the Dumont that I grew up with would look modern next to it. Do you recall the brand?

By the time I was in double digits, the Dumont was down as much as it was working (it had 38 tubes in it IIRC). It was on the fritz in November of 1963 so I missed the whole thing.

The good part is that I never got used to having a working TV around so I never got the TV habit. Today I never watch it at all. No great loss I think.

Tin Can
21-Mar-2021, 16:00
No, kids like me were not allowed close enough to see the name

I got even by making a simple TV jammer age 10, TV only worked when I was allowed to watch

I have collected all kinds of early gadgets. 1930's Wire Recorders, console phonographs. 78 RPM record makers. I still have 3 old radios

Father threw it all away every move, we moved often, so I still collect

https://live.staticflickr.com/65535/51059928853_55fb187b0d_o.jpg (https://flic.kr/p/2kMZtWV)Round TV (https://flic.kr/p/2kMZtWV) by TIN CAN COLLEGE (https://www.flickr.com/photos/tincancollege/), on Flickr

https://live.staticflickr.com/65535/51060737057_3d9a509b49_o.jpg (https://flic.kr/p/2kN4Cct)Round 2 (https://flic.kr/p/2kN4Cct) by TIN CAN COLLEGE (https://www.flickr.com/photos/tincancollege/), on Flickr



I bought one of these for $50, 30 years ago and tried to fix it, gave up and installed a 13" inside behind the glass. Fooled a lot of people.