Lumia 830 doesn't seem to be 10MP

[blue1k]

Just picked up my 830 and noticed that the photos are 9MP not 10 (even in 4:3 mode). What gives?

 

[TexasLabRat]

http://forums.windowscentral.com/nokia-lumia-830/333079-camera-aspect-ratio-16-9-4-3-a.html

 

[blue1k]

http://forums.windowscentral.com/nokia-lumia-830/333079-camera-aspect-ratio-16-9-4-3-a.html

I understand aspect ratio. It shoots 8mp on 16:9 and 9.3 on 4:3. That doesn't answer my question. We know it is a 4:3 sensor.

 

[slivy58]

I understand aspect ratio. It shoots 8mp on 16:9 and 9.3 on 4:3. That doesn't answer my question. We know it is a 4:3 sensor.

I've noticed this as well and wondering the same thing, maybe MS decided to just round it off :grin:, wouldn't put it past them since they touted it came w/Denim yet neglected to announce it was only the "beta" version of sorts.

 

[Fred Wilson2]

The 10mp has nothing to do with the file size of the .jpg (or whatever film format you save the pictures).
10MP is the number of "pixels" that the sensor has, not the MB size or number of pixels of or in the saved image.

Now, having said that, just because a sensor has, for instance, 10MP that doesn't have to mean that the area of the sensor that the firmware uses to extract the data from is the whole sensor, it can very well just be a subset (and usually is) of the total sensor size.
The "effective" sensor size could very well just contain 8MP when photos are shot in the 4:3 format, etc.
10MP is the number of pixels that the whole sensor has, not the "effective" number of pixels that a particular photo format ratio will see.



Fred

 

[blue1k]

The 10mp has nothing to do with the file size of the .jpg (or whatever film format you save the pictures).
10MP is the number of "pixels" that the sensor has, not the MB size or number of pixels of or in the saved image.

Now, having said that, just because a sensor has, for instance, 10MP that doesn't have to mean that the area of the sensor that the firmware uses to extract the data from is the whole sensor, it can very well just be a subset (and usually is) of the total sensor size.
The "effective" sensor size could very well just contain 8MP when photos are shot in the 4:3 format, etc.
10MP is the number of pixels that the whole sensor has, not the "effective" number of pixels that a particular photo format ratio will see.



Fred

Ya you are right. I guess they are advertising the sensor area. 1020 was the same.

Thanks.

 

[TexasLabRat]

Ya you are right. I guess they are advertising the sensor area. 1020 was the same.

Thanks. 

And this was the point of the post I linked..which featured a nice graphic showing how it works mathematically, if one was actually inclined to read it.

 

[blue1k]

And this was the point of the post I linked..which featured a nice graphic showing how it works mathematically, if one was actually inclined to read it.

Ah sorry it didn't load on my phone. Missed that. Only saw other comments in the thread. And yes, I would have bothered to read it.

 

[msirapian]

It's not at all marketing or adversiting, it's the reality. The sensor is round, you have to crop a rectangle out of it.

Look at this illustration (for the Nokia 808, it's the same for the 1020, and, the principle applies to your 830)

http://www.esato.com/gfx/news/img/nokia-808-pureview-41-megapixel-image-sensor_1330382356.jpg

 

[blue1k]

It's not at all marketing or adversiting, it's the reality. The sensor is round, you have to crop a rectangle out of it.

Look at this illustration (for the Nokia 808, it's the same for the 1020, and, the principle applies to your 830)

http://www.esato.com/gfx/news/img/nokia-808-pureview-41-megapixel-image-sensor_1330382356.jpg

No I meant they should advertise the effective size. I understand the physics.

My SLR is advertised at the effective output of the image as are other cameras.

 

[a5cent]

No I meant they should advertise the effective size. I understand the physics. ��

My SLR is advertised at the effective output of the image as are other cameras.

A) No smartphone OEM does this. Everyone advertises sensor resolution. Advertising the lower MP number in the interest of "honesty" would be akin to one OEM deliberately putting themselves at a marketing disadvantage.

B) Many camera sensors are rectangular, not round, so in those situations advertised sensor resolution = image resolution (edit: provided sensor aspect ratio = image aspect ratio).

C) Even if an OEM using a round sensor wanted to be more "honest", which of the many aspect ratios should they choose? As with all specs, this is an oversimplification, but in this particular instance it may not be the worst choice.

 

[stephen_az]

Just picked up my 830 and noticed that the photos are 9MP not 10 (even in 4:3 mode). What gives?

This is not unusual and, contrary to some ill informed claims, is also not false advertising. Digital sensors use the outer margin of pixels for de-mosaicing. Some also still sacrifice some pixels for Bayer filters and other image correction technology. Long and short of it is the sensor is 10MP but the images will always be somewhat smaller. I expect one or another element of the pureview technology probably samples some pixels as well. BTW, there is no reason for Microsoft or any other company (since it is industry standard) to clarify since the images are being produced by a 10MP sensor. The MP is the sensor size not end image dimensions.

 

[stephen_az]

It's not at all marketing or adversiting, it's the reality. The sensor is round, you have to crop a rectangle out of it.

Look at this illustration (for the Nokia 808, it's the same for the 1020, and, the principle applies to your 830)

http://www.esato.com/gfx/news/img/nokia-808-pureview-41-megapixel-image-sensor_1330382356.jpg

The sensor is not round, it is rectangular. Except for some rare and older cameras where the physical aperture was smaller than the sensor, the explanation for this is because not all physical pixels on a sensor are used in digital images. A variable percentage (to vastly oversimplify) are used to produce and refine/correct the generated image....

 

[DenniSundaY]

Same as on the 930. Claims to have a 20MP camera (probably has indeed a 20MP chip) but only shoots photos in 19MP max. Still, if that results in better quality photos, I don't mind

 

[stephen_az]

No I meant they should advertise the effective size. I understand the physics. ��

My SLR is advertised at the effective output of the image as are other cameras.

Comparing DSLRs to glorified P&S cameras (all camera phones) is not even close to apples to apples. If you look around you will see that distinction of actual vs effective pixels is not the standard in the world of camera phones, nor should it be since they are correctly advertising sensor size. It is not unethical nor is it truly misleading. If the DSLR community didn't have part of its origin in pixel peepers, and some pros and semi pros who really do need to know total pixels reflected in images, you also wouldn't see it noted in those advertisements. For that matter, there are plenty of DSLRs that do not advertise effective pixels.

I am sorry but while you may understand physics, the physics being discussed by people here are actually wrong. This is neither about physics in the sense some here conceive nor advertising. It is about how a 10MP sensor uses 10MP worth of pixels (and all of the photosites therein) to produce an image. It is not a 9.X MP sensor/camera. It is a 10MP sensor that uses a portion of those pixels to produce an image (and optimize it for your use).

 

[DenniSundaY]

Comparing DSLRs to glorified P&S cameras (all camera phones) is not even close to apples to apples. If you look around you will see that distinction of actual vs effective pixels is not the standard in the world of camera phones, nor should it be since they are correctly advertising sensor size. It is not unethical nor is it truly misleading. If the DSLR community didn't have part of its origin in pixel peepers, and some pros and semi pros who really do need to know total pixels reflected in images, you also wouldn't see it noted in those advertisements. For that matter, there are plenty of DSLRs that do not advertise effective pixels.

I am sorry but while you may understand physics, the physics being derived by people here are actually wrong. This is neither about physics at all nor advertising. It is about how a 10MP sensor uses 10MP worth of pixels (and all of the photosites therein) to produce an image. It is not a 9.X MP sensor/camera. It is a 10MP sensor that uses a portion of those pixels to produce an image (and optimize it for your use).

Already thought it was weird people were referring at it as 'physics' because indeed it is simply said just how many pixels are being used on the sensor for that image.

But what I don't know, is why don't they use the entire chip if I may ask? Is it because the chip isn't truly 3:2 ratio or something?

 

[TexasLabRat]

Already thought it was weird people were referring at it as 'physics' because indeed it is simply said just how many pixels are being used on the sensor for that image.

But what I don't know, is why don't they use the entire chip if I may ask? Is it because the chip isn't truly 3:2 ratio or something?

Look in post #3 in the thread that I linked above for a visual explanation. In a nutshell, the light coming into the camera via the lens and onto the sensor is a circle. The sensor is a rectangle. Depending on the aspect ratio chosen for the shot, the usable sensor area is cropped vertically or horizontally. Either choice results in a lower overall usable pixel count for the shot than the total available in the sensor as a whole (ie the "advertised" pixel count).

 

[DenniSundaY]

Look in post #3 in the thread that I linked above for a visual explanation. In a nutshell, the light coming into the camera via the lens and onto the sensor is a circle. The sensor is a rectangle. Depending on the aspect ratio chosen for the shot, the usable sensor area is cropped vertically or horizontally. Either choice results in a lower overall usable pixel count for the shot than the total available in the sensor as a whole (ie the "advertised" pixel count).

But still weird, that the image from the lens even overlaps the whole array of pixels, so I thought when you make the chip some smaller or the image larger, why can't the full resolution be utilized? (or is that something that is out of the question haha. Don't know how it ask works so ask)

 

[TexasLabRat]

But still weird, that the image from the lens even overlaps the whole array of pixels, so I thought when you make the chip some smaller or the image larger, why can't the full resolution be utilized? (or is that something that is out of the question haha. Don't know how it ask works so ask)

in theory you could use a 4:3 sensor and make it so that it completely fit in the circle, but you'd be "wasting" more of the light that was entering via the lens. In addition, 16:9 mode pictures would be even more cropped pixel-wise (similar to the situation on the 520). It's a matter of optical system optimization.

 

[DenniSundaY]

in theory you could use a 4:3 sensor and make it so that it completely fit in the circle, but you'd be "wasting" more of the light that was entering via the lens. In addition, 16:9 mode pictures would be even more cropped pixel-wise (similar to the situation on the 520). It's a matter of optical system optimization.

You are right, thanks for the explanation. I wasn't questioning the 'laws of photography technology' haha but I was just wondering