Ad
Ad
Ad
Pages: « 1 [2]   Bottom of Page
Print
Author Topic: 70 MP CMOS sensor  (Read 4733 times)
Kolor-Pikker
Jr. Member
**
Offline Offline

Posts: 57


« Reply #20 on: April 11, 2013, 07:16:02 AM »
ReplyReply

Hi Color Pikker

sorry that wouldnīt do as the Zeiss is for 35mm and this chip has 63,5x35,4mm

This needs MF lenses. It will also be totally uncritical in sharpness as any decent MF lens will feed the 8,2 Micron easily (thatīs about the Pixelsize of the old 20 Mpix backs)

Regards
Stefan
I was talking about the 70mp cmosis sensor.
Logged
Stefan.Steib
Sr. Member
****
Offline Offline

Posts: 414



WWW
« Reply #21 on: April 11, 2013, 07:29:12 AM »
ReplyReply

I was talking about the 70mp cmosis sensor.

sorry -  yep - that will be a tough one.

Regards
Stefan
Logged

Because Photography is more than Technology and "as we have done this all the time"
www.hartblei.de     www.hcam.de    www.spectralize.com
torger
Sr. Member
****
Offline Offline

Posts: 1407


« Reply #22 on: April 11, 2013, 08:38:51 AM »
ReplyReply

2.5" sensor usually means something like 1/2.5" sensor, that is rather small... sensor makers have a funny way of relating inches to sensor size which I have never truly figured out.

For example, Nikon 1 has a "1 inch sensor", and the actual size is 13.2x8.8mm, I wonder where 25.4mm fits in there?

When 2.5" sensor is talked about in compact cameras the size is 5.76x4.29mm, but I doubt it would be that tiny. But I also find it highly unlikely that it would be 63.5 in diagonal. Is there an official statement of the actual exact measurements of the sensor?
« Last Edit: April 11, 2013, 08:45:29 AM by torger » Logged
Stefan.Steib
Sr. Member
****
Offline Offline

Posts: 414



WWW
« Reply #23 on: April 11, 2013, 10:04:49 AM »
ReplyReply

Hi Torger

Iīm pretty sure this is what it says, the camera is much too big for a small 1/2,5" and it sports full PL mount which also doesnīt make sense for such small stuff.
The datasheet is definite - it says 2,5".

http://www.astrodesign.co.jp/english/astro/News/NAB_Debut/ASTRONEWSE_AH4800_20130405.pdf
Logged

Because Photography is more than Technology and "as we have done this all the time"
www.hartblei.de     www.hcam.de    www.spectralize.com
EricWHiss
Sr. Member
****
Offline Offline

Posts: 2398



WWW
« Reply #24 on: April 11, 2013, 12:08:06 PM »
ReplyReply

It sure looks like video is were all the game is, and probably because of the higher budgets.
Logged

Authorized Rolleiflex Dealer:
Find product information, download user manuals, or purchase online - Rolleiflex USA
Kolor-Pikker
Jr. Member
**
Offline Offline

Posts: 57


« Reply #25 on: April 11, 2013, 12:21:31 PM »
ReplyReply

Hi Torger

Iīm pretty sure this is what it says, the camera is much too big for a small 1/2,5" and it sports full PL mount which also doesnīt make sense for such small stuff.
The datasheet is definite - it says 2,5".

http://www.astrodesign.co.jp/english/astro/News/NAB_Debut/ASTRONEWSE_AH4800_20130405.pdf

On the other hand, why would the camera have a CP.2 lens on it? Does it actually cover the supposed 63x35mm format, twice as wide and 50% taller than the intended image circle?

Edit:
Quote
2.5" sensor usually means something like 1/2.5" sensor, that is rather small... sensor makers have a funny way of relating inches to sensor size which I have never truly figured out.

For example, Nikon 1 has a "1 inch sensor", and the actual size is 13.2x8.8mm, I wonder where 25.4mm fits in there?

Ahh! Bingo! It is related to the TV tube inch measurement, not in fractional inches, but indeed in whole inches.

1" is technically defined as 12.8 x 9.6mm, which means that multiplying the size by 2.5x results in a size of 32x24mm, making it smaller than 35mm format in the horizontal dimension, and the final image is likely going to be smaller still, because it will use a recording ratio typical for video rather than 4:3.

All in all, the sensor size physical recorded image will be somewhat bigger than the standard S35 of cinema cameras, and even the Epic sensor which is 30mm wide. This means that not all PL lenses will work, and why the CP.2 is demoed, full-frame lenses are likely to have better coverage for the whole sensor.
« Last Edit: April 11, 2013, 12:38:47 PM by Kolor-Pikker » Logged
BJL
Sr. Member
****
Offline Offline

Posts: 5124


« Reply #26 on: April 11, 2013, 01:33:44 PM »
ReplyReply

P. S. Sorry, just noticed the post above mine. And 32mm wide would be natural, just fitting into the 33x26mm maximum field size limit of modern sensor fab. equipment to avoid on-wafer stitching.

AH-4800 Image sensor
: 2.5inch 33million pixels single plate CMOS
...
http://www.astrodesign.co.jp/english/news/news-20130405-1790.html
My guess is that this "2.5inch" is in the usual bizarre convention of video sensors, where the actual diagonal is about 2/3 of the stated number, like 4/3" meaning 22.5mm diagonal. So scaling up: 22.5mm * (2.5" / 4/3") = 42.2mm, fairly close to the 43.2mm diagonal of 36x24mm "35mm format". That seems a good size choice for a camera of such high resolution, which is likely to want access to higher resolution still-camera lenses.
« Last Edit: April 11, 2013, 01:36:36 PM by BJL » Logged
Kolor-Pikker
Jr. Member
**
Offline Offline

Posts: 57


« Reply #27 on: April 11, 2013, 02:13:45 PM »
ReplyReply

In case anyone is wondering, for curiosity's sake, the inch size was developed way back before the 90's when video cameras used CRT tubes to capture the image instead of CCDs. Tubes were typically measured in terms of diameter in fractional inches, but the useable area was only a central portion of the tube, so for any given size, a smaller center crop was used.

Since by the late 80's a whole industry was already built around the size convention of tubes, it made sense to keep it when talking about digital sensors, so a 2/3" lens could stay 2/3" and not some new made up figure.

I do wonder why NHK used such an outdated sizing method for a large sensor camera.
Logged
Stefan.Steib
Sr. Member
****
Offline Offline

Posts: 414



WWW
« Reply #28 on: April 11, 2013, 02:16:34 PM »
ReplyReply

probably you are right, these measurements are really odd and misleading.
But then: a 33 Mpix chip with that data is nowhere mentioned. Out of the blue ?

Hmmmm.  Huh
Logged

Because Photography is more than Technology and "as we have done this all the time"
www.hartblei.de     www.hcam.de    www.spectralize.com
Hening Bettermann
Sr. Member
****
Offline Offline

Posts: 557


WWW
« Reply #29 on: April 11, 2013, 06:37:40 PM »
ReplyReply

Here is something about those sensor sizes:
http://www.dpreview.com/glossary/camera-system/sensor-sizes
Logged

Stefan.Steib
Sr. Member
****
Offline Offline

Posts: 414



WWW
« Reply #30 on: April 12, 2013, 06:03:23 PM »
ReplyReply

Thanks for the link Hening !

1/2.5"    4:3    10.160    7.182    5.760    4.290

But this would mean this camera has only a 5,7 x 4,2 mm large chip ?
I donīt think so !

Logged

Because Photography is more than Technology and "as we have done this all the time"
www.hartblei.de     www.hcam.de    www.spectralize.com
BJL
Sr. Member
****
Offline Offline

Posts: 5124


« Reply #31 on: April 12, 2013, 07:18:36 PM »
ReplyReply

1/2.5"    4:3    10.160    7.182    5.760    4.290

But this would mean this camera has only a 5,7 x 4,2 mm large chip ?
This sensor is described at 2.5", not 1/2.5" --- a size not on that list. By the way, some Sony data sheets for its "APS-C" sized sensors describe them with wording like "APS Size Diagonal 28.4 mm (Type 1.8)",
where "Type 1.8" s a synonym for the weird '1.8 inch' specification:
http://www.sony.net/Products/SC-HP/cx_news/vol28/pdf/icx413np.pdf

The size in fake inches or "Type" only refers to the diagonal measurement. For example, there are 2/3" sensors in different shapes, some 4:3 for stills, others 16:9 for HD video, with the common dimension being the diagonal of about 11mm.
Logged
ErikKaffehr
Sr. Member
****
Offline Offline

Posts: 7327


WWW
« Reply #32 on: April 12, 2013, 11:17:07 PM »
ReplyReply

Hi,

I think it was shown with a Compact Prime? That would be something 43 mm diagonal at maximum. 4/3 has a diagonal of 21.6 mm, 2.5 / 1.33 * 21.6 -> 40.5, slightly sub 135 full frame.


My guess is that the sensor size is around 35.4 x 19 mm, assuming 1080P side ratios.

Best regards
Erik

Thanks for the link Hening !

1/2.5"    4:3    10.160    7.182    5.760    4.290

But this would mean this camera has only a 5,7 x 4,2 mm large chip ?
I donīt think so !


Logged

Kolor-Pikker
Jr. Member
**
Offline Offline

Posts: 57


« Reply #33 on: April 13, 2013, 04:33:20 AM »
ReplyReply

Didn't we already figure the size thing out? It's a roughly 32x24mm sensor from a 33x26mm wafer process.

2.5" is 63.5mm, or 42.3mm diagonal according to tube sizing, which would result either in a roughly 36x20mm 16:9 sensor or 33x24.75mm 4:3 sensor, the latter of which sounds more practical from a manufacture point of view.

4:3 is not impractical for video, because as we can see in the Alexa, the extra sensor space can be used to emulate the full area of 35mm film stock, which allows the use of anamorphic lenses without any crop. With Cooke having recently announced a line of anamorphic lenses, we may just end up seeing more video cameras that have 4:3 sensors.
« Last Edit: April 13, 2013, 04:35:25 AM by Kolor-Pikker » Logged
Pages: « 1 [2]   Top of Page
Print
Jump to:  

Ad
Ad
Ad