Topic: Sony a7r II - 42MP BSI CMOS (Read 11792 times)

rdonson · « **on:** June 10, 2015, 02:32:15 pm »

http://www.dpreview.com/articles/8917769536/sony-alpha-a7r-ii-has-42-4mp-on-full-frame-bsi-cmos-sensor

I think Canon just got schooled.

sbay · « **Reply #1 on:** June 10, 2015, 03:00:22 pm »

This thing has a "back-illuminated sensor". I'd never heard of this before but the wikipedia article makes the technology sound promising for greater sensitivity. What can be expected from this?

capital · « **Reply #2 on:** June 10, 2015, 03:29:20 pm »

Quote from: sbay on June 10, 2015, 03:00:22 pm

This thing has a "back-illuminated sensor". I'd never heard of this before but the wikipedia article makes the technology sound promising for greater sensitivity. What can be expected from this?

It means more photons hit the light sensitive portion of the sensor, as opposed to being masked/blocked off by wiring, the stuff that connects to the photo sensitive material.

As the size of the pixel increases, the utility of backside illumination (BSI) diminishes simply because the ratio of wiring to photosensitive area goes in favor of the photosensitive area. BSI allows you to increase density of pixels while keeping the pixel's light gathering capacity closer to the prior generation's non-BSI lower megapixel camera.

Stefan.Steib · « **Reply #3 on:** June 10, 2015, 05:18:54 pm »

And not to forget BSI will improve resistance to steeper Ray angles hitting the sensor.
So all the ultra short wideangles will now find a perfect home on this sensor.

And: of course that is perfect for Shift and Tilt usage. I love it !

rdonson · « **Reply #4 on:** June 10, 2015, 05:49:58 pm »

If you're interested in what BSI can do check out a review of the Samsung NX1. Its APS-C not full frame but is likely indicative of what might be in store for the A7r

Guillermo Luijk · « **Reply #5 on:** June 11, 2015, 03:40:54 am »

Another advantage of maximising the light collection surface is making the AA filter less necessary to avoid aliasing (moiré), because the sensor itself averages the light gathered in a wider area. As a side effect this averaging acts as a LPF.

Regards.

MatthewCromer · « **Reply #6 on:** June 11, 2015, 07:27:54 am »

Should improve corner sharpness too, particularly with older RF-style lenses. The optical / pixel wells are much shallower with this new design.

Paulo Bizarro · « **Reply #7 on:** June 11, 2015, 09:22:57 am »

Quote from: rdonson on June 10, 2015, 02:32:15 pm

http://www.dpreview.com/articles/8917769536/sony-alpha-a7r-ii-has-42-4mp-on-full-frame-bsi-cmos-sensor

I think Canon just got schooled.

It baffles me why some people feel the need to make such statements... schooled in what? Again the DR sermon? Or perhaps Canon needs to learn how to make a lens system? Oh, wait, that is actually Sony... whatever.

I have moved from Canon to Sony A7 system, both are fantastic, Sony stills has a lot to leanr though, in terms of actually building a system that lasts for more than 5 years, without disapearing...

hjulenissen · « **Reply #8 on:** June 11, 2015, 09:43:15 am »

Quote from: Guillermo Luijk on June 11, 2015, 03:40:54 am

Another advantage of maximising the light collection surface is making the AA filter less necessary to avoid aliasing (moiré), because the sensor itself averages the light gathered in a wider area. As a side effect this averaging acts as a LPF.

Regards.

I believe that similar filtering (~100% fillrate) can be had by using microlenses, with the side-effect that your f/1.2 lenses will be more like f/1.4 lenses?

Anyways, this kind of boxcar filtering is a crude prefilter before sampling. You need to have additional filtering (lens diffraction, scene/camera movement) in order to suppress aliasing by a lot. Fortunately, increasing pixel counts means that diffraction/movement is filtering more on a pixel level.

-h

scooby70 · « **Reply #9 on:** June 11, 2015, 09:49:36 am »

Quote from: Paulo Bizarro on June 11, 2015, 09:22:57 am

I have moved from Canon to Sony A7 system, both are fantastic, Sony stills has a lot to leanr though, in terms of actually building a system that lasts for more than 5 years, without disapearing...

Chill, it's just a bit of fun and it's not as if Canon aren't above doing a disappearing act. FD anyone?

sbay · « **Reply #10 on:** June 11, 2015, 09:54:24 am »

Quote from: rdonson on June 10, 2015, 05:49:58 pm

If you're interested in what BSI can do check out a review of the Samsung NX1. Its APS-C not full frame but is likely indicative of what might be in store for the A7r

I looked briefly at the NX1 and the reviews seem to state that it's image quality is inline with competitors. However I don't know what the baseline should be -- e.g. maybe without BSI the samsung would be much worse.

I'm glad to hear that it will help with T/S lenses. I have a few of those.

Rand47 · « **Reply #11 on:** June 11, 2015, 02:50:27 pm »

Quote

building a system that lasts for more than 5 years, without disapearing...

Amen, brother.... Anyone want to buy some nice A-mount lenses? Heck, when they designed the NEX they didn't even get the T on the end of the name before it disappeared!

Rand

Mousecop · « **Reply #12 on:** June 11, 2015, 02:53:04 pm »

Quote from: sbay on June 10, 2015, 03:00:22 pm

This thing has a "back-illuminated sensor". I'd never heard of this before but the wikipedia article makes the technology sound promising for greater sensitivity. What can be expected from this?

As noted, it improves noise performance a little bit, though the increase in resolution will probably degrade noise performance a little bit.

I expect the end result will be more detail than the current a7r (36mp) with roughly the same noise /DR performance.

pegelli · « **Reply #13 on:** June 11, 2015, 03:43:38 pm »

Quote from: Isaac on June 11, 2015, 03:10:27 pm

"Advantages of the phase-detection AF are assured even with an A-mount lens mounted via LA-EA3…"

Only for SSM or SAM lenses. The older method "screwdriver" AF lenses will need a LA-EA4 with translucent mirror to AF.

pegelli · « **Reply #14 on:** June 11, 2015, 04:37:52 pm »

Quote from: Isaac on June 11, 2015, 04:18:27 pm

Apparently Minolta introduced SSM lenses back in 2003.

Ok, nit corrected

Hening Bettermann · « **Reply #15 on:** June 11, 2015, 04:51:45 pm »

Quote from: Stefan.Steib on June 10, 2015, 05:18:54 pm

And not to forget BSI will improve resistance to steeper Ray angles hitting the sensor.
So all the ultra short wideangles will now find a perfect home on this sensor.
[...] I love it!

Does this mean that RF wideangles will become usable without color shifts and soft corners ?? No need for retrofocus design? I'd love it!

Paul Roark · « **Reply #16 on:** June 11, 2015, 07:54:09 pm »

I hope the image of the sensor ray angle improvement shown here -- http://www.sony.net/Products/di/en-us/products/dkw5/index.html -- does allow those Leica M wides to work, but I think we need to see some real world tests. Even without the particular sensitivity to ray angle that the typical digital sensors have, the more symmetrical wides will still suffer from more light falloff/vignetting.

Given the boatload of features/improvements and substantially increased price, I'm guessing Sony is going to do very well with this camera.

Paul
www.PaulRoark.com

Paulo Bizarro · « **Reply #17 on:** June 12, 2015, 06:33:32 am »

Quote from: scooby70 on June 11, 2015, 09:49:36 am

Chill, it's just a bit of fun and it's not as if Canon aren't above doing a disappearing act. FD anyone?

Oh I'm cool, don't worry:)

Canon EF mount and EOS system has been going for more than 20 years... much longer than any Sony system really.

Hening Bettermann · « **Reply #18 on:** June 12, 2015, 07:23:41 am »

Thanks for your reply, Paul.

Guillermo Luijk · « **Reply #19 on:** June 15, 2015, 05:18:58 pm »

A couple of videos about AF on the A7R II with Canon lenses:

http://www.youtube.com/watch?v=qW36e_icsic

http://www.youtube.com/watch?v=rdhvDg2dkiM

Watch out Canon!

Author Topic: Sony a7r II - 42MP BSI CMOS (Read 11792 times)