Canon LF sensor

[mmerig]

Maybe I missed it, but there is no information on pixel size for the big sensor. Given the trade-off between pixel size and light sensitivity, the pixels are probably quite large, so the resolution may not be that great. I think their goal was a very sensitive sensor, and to have reasonable resolution, they had to make it big.

[Havoc]

This is meant for scientific and industrial use. Frm the article it was used for astronomy at the KISO observatory in Japan. (check their site, thei have a great scanner for plates) So they probably also cooled it to 170K or something like that.

[Pere Casals]

Why would you use an RB (Rotating Back) with a square format?

PD: this information is wrong:

Mark, in this case R is for Reflex not for Rotating. Graflex RB vs Mamiya RB, they are using same letters from different words.

[Pere Casals]

http://www.canon.com/technology/future/cmos.html

This would rock in a RB SLR...

Big sensors are used in astronomical telescopes.

ESA's Gaia mission telescope had 106 MF sensors combined in a composite sensor covering 3800 cm2.

[Eric Woodbury]

When you order your copy of this sensor, don't forget to order a lens with 300 mm image circle and a usable aperture of f/1.6. Diffraction limited.

[Mark Sawyer]

Mark, in this case R is for Reflex not for Rotating. Graflex RB vs Mamiya RB, they are using same letters from different words.

Now you've got me curious, as I used to use an RB pretty regularly... None of Mamiya's other reflexes (Mamiya 645, C220, C-330, or other TLR or 35mm SLRs) used the letter R to distinguish that feature. And Camera-wiki.org states, "The naming of the camera RB67 stood for Rotating Back 6 × 7", (http://camera-wiki.org/wiki/Mamiya_RB67#Bibliography).

Do you have any source for RB standing for Reflex, not Rotating or Revolving? And what did the B stand for?

Either way, an 8x8-inch digital back would be pointless on a 6x7-cm camera...

[Pere Casals]

Now you've got me curious, as I used to use an RB pretty regularly... None of Mamiya's other reflexes (Mamiya 645, C220, C-330, or other TLR or 35mm SLRs) used the letter R to distinguish that feature. And Camera-wiki.org states, "The naming of the camera RB67 stood for Rotating Back 6 × 7", (http://camera-wiki.org/wiki/Mamiya_RB67#Bibliography).

Do you have any source for RB standing for Reflex, not Rotating or Revolving? And what did the B stand for?

Either way, an 8x8-inch digital back would be pointless on a 6x7-cm camera...

Mark, sorry, I was mistaken, the Graflex RB is for Revolving Back. https://graflex.org/articles/series-d/

I relied in a bad source.

[Havoc]

When you order your copy of this sensor, don't forget to order a lens with 300 mm image circle and a usable aperture of f/1.6. Diffraction limited.

I understand the need for the image circle, but why would it need to be f/1.6? Certainly if the sensor is touted to be usable in 0.3 lux scenes.

[Eric Woodbury]

Lenses are limited in their ability to focus a point. It's called the diffraction limit. The faster the lens, the smaller the spot you can focus. The sensor in question here has 2 micron pixels. To get an infinitely small spot to focus into a pixel that size with green light (at least most of it, first null of the Airy disk), requires this insane f-number. There are some ways to get around this problem, but not practical for normal humans.

BTW, they still fly film in U-2s. Film is good stuff at a bargain price (relatively speaking).

[Pere Casals]

Lenses are limited in their ability to focus a point. It's called the diffraction limit. The faster the lens, the smaller the spot you can focus. The sensor in question here has 2 micron pixels. To get an infinitely small spot to focus into a pixel that size with green light (at least most of it, first null of the Airy disk), requires this insane f-number. There are some ways to get around this problem, but not practical for normal humans.

BTW, they still fly film in U-2s. Film is good stuff at a bargain price (relatively speaking).

f/1.6 is not necessary, 2 micron lines is 4 micron for a line pair, this is 1/0.004 = 250 lp/mm. Difraction limit at f/5.6 is 283 lp/mm, so in theory a f/5.6 lens can outresolve that giant sensor.

A suitable a lens for that sensor (if we want matching resolving power) may weight around 30kg, with best sharpness in the center at some f/4, and acceptable performance across all the field by some f/11, if one takes a look to some HiRes aerial designs that were popular.

But it would not be necessary to use a lens that outresolves the sensor. A Nikon D3400 also has usually much more pixels than the popular lenses are able to resolve...