Something I've been wanting to ask

shuttervelocity

TPF Noob!
Joined
Jan 16, 2012
Messages
137
Reaction score
21
Location
San Jose CA
Can others edit my Photos
Photos OK to edit
Its too vague of a question to search...so here goes.

We've all read/argued/concluded that this megapixels war is up to no good. Stuffing too many pixels in tiny sensors and all that. I go back to some of the pics taken with my 4 MP canon A80 (which required 4 AA batteries and would burn through them within 100 shots or so) and those pics are just amazing. Even though the camera was rated at 400 ISO, I've taken shots of people with sunset in the background and both the sky, as well as features of the people including the grass they're standing on, are all completely discernible. But I love the features of newer cameras. With their tiny ergonomic design, rechargeable batteries, superb zoom, etc. So, I'm torn in decisions. Aren't we all? :lmao:

Lets take 2 APS-C size sensor cameras. One is rated at 8 MP max resolution and the other at 16 MP max res. If I set the Image size to 8 MP on the 16 MP camera, does it mean its essentially the same as the sensor rated at 8 MP camera? Or is the camera going to take a picture at 16 MP first and the use its processor to reduce the size to 8 MP and write on the card?

I do have a follow up question, but it depends on the answer i get for my first question. :mrgreen:

Thanks
Sam
 
I think the sensor still works the same way, it just processes the image more compressed.
 
correct me if I'm wrong, but I think the sensor just captures the image, its the processor that does all the processing. But since they are stuffing so many pixels on the sensor whose size is not increasing, that the pixels are so close and light falling on one pixel can interfere with light falling on the next one and so on. the processor then comes along and "cleans" up the image.
 
You have also neglected in there the actual size of the sensors. A larger 8MP sensor is going to give you better quality than a smaller 8MP sensor. So... it's not all equal.
When you are saving in a reduced size it's done in processing in the camera.
 
You have also neglected in there the actual size of the sensors. A larger 8MP sensor is going to give you better quality than a smaller 8MP sensor. So... it's not all equal.
When you are saving in a reduced size it's done in processing in the camera.
no, but that's what I said. For comparison, lets take 2 APS-c sized sensor cameras. The actual size of the sensors would be the same right?
 
When you set a 16MP camera to 8MP, angels will weep...there will be gnashing of teeth.
The image taken is still 16MP but during JPG conversion, it will downsample the image to 8MP. There is no good reason to ever do this.
EVER.
Shoot in RAW if possible, Full Size JPG if you're confused by RAW.
Comparing the 8MP to the 16MP sensor of APS-C size. I'd say that the 16 would be better because chances are that it is a newer generation sensor with better signal to noise and newer processing.
 
For comparison, lets take 2 APS-c sized sensor cameras. The actual size of the sensors would be the same right?
No. Canon's APS-C sensors are somewhat smaller than Nikon's APS-C size sensors, which is why Canon APS-C cameras have a 1.6x crop factor and Nikon APS-C size sensors have a 1.5x crop factor.
 
Its too vague of a question to search...so here goes.

We've all read/argued/concluded that this megapixels war is up to no good. Stuffing too many pixels in tiny sensors and all that. I go back to some of the pics taken with my 4 MP canon A80 (which required 4 AA batteries and would burn through them within 100 shots or so) and those pics are just amazing. Even though the camera was rated at 400 ISO, I've taken shots of people with sunset in the background and both the sky, as well as features of the people including the grass they're standing on, are all completely discernible. But I love the features of newer cameras. With their tiny ergonomic design, rechargeable batteries, superb zoom, etc. So, I'm torn in decisions. Aren't we all? :lmao:

Lets take 2 APS-C size sensor cameras. One is rated at 8 MP max resolution and the other at 16 MP max res. If I set the Image size to 8 MP on the 16 MP camera, does it mean its essentially the same as the sensor rated at 8 MP camera? Or is the camera going to take a picture at 16 MP first and the use its processor to reduce the size to 8 MP and write on the card?

I do have a follow up question, but it depends on the answer i get for my first question. :mrgreen:

Thanks
Sam
I think you are missing out on why that A80's images were/are appealing to you. It is NOT because of the MPs but because of sensor size, A P & S sensor is smaller than an APC-C and has a great advantage of Deeper DOF ( which most portrait shooters don't want) but that is why you saw everything in your image BG, Person Grass etc sharp or within the Depth of Focus. Its' not a MPixel thing.

You can do the same/similar thing with an APS-C sensor camera, but you have to choose your, Lens, subject distance and aperture wisely. Getting a 50MM 1.8 and shooting wide open with your subject 7 feet away. Will not do it.
 
oh. I guess I've been barking up the wrong tree then. So, a newer 16MP camera with the same sensor size as my 8MP Rebel XT is not necessarily a bad thing. :)
 
Extreme example: let's take a Nikon D70 and Nikon D7000. Both have identically sized sensors. D70 goes to ISO 1600, D7000 goes to 25,600. If you blow up on screen to 100%, you won't see that much of an improvement, but if you print it at any given size, the D7000 is miles ahead? Why? each dot of noise is now so much smaller by comparison.
 
The issue is further clouded by the fact that the Nikon D70 has a CCD (Charge Coupled Device) type image sensor, while the D7000 has CMOS (Complimentry Metal-Oxide Semiconductor) type image sensor.
 
oh. I guess I've been barking up the wrong tree then. So, a newer 16MP camera with the same sensor size as my 8MP Rebel XT is not necessarily a bad thing. :)

I think the other the thing to think about is how the Manufacters set up those camera.

Years ago I was a film guy, was NEVER going to shoot digital. But for fun I picked up a Canon A60, The model just before/below yours. Iwas blows away at how good a little P & S could be and how great the photos were.

So I decided to get a Canon 20D to use along side my film cameras. But the first week I had it I was a little disapointed in the images compared to the little A60, Till I realized that in the little consumer P & S they amped up the saturation and sharpness because the users of those camera would not typically be doing any post processing. And the DSLR, Canon went for Low Noise and Image quality over pop. But it could easily be had with just a bit of post processing.

But after that point, My film cameras were put on a shelf as decoration and I never looked back and now Shoot with Full Frame Canons. Happy boy :)
 
"All other things being equal," and at low iso's I would suspect that the 16mp photo downsampled to 8mp will retain more detail then the 8mp camera. This is due to the way sensors work: individual pixels on a sensor are only capable of seen R G or B, not all three--the full color result is then interpolated to create the final image, so an 8mp sensor does not really equate to 8mp of RGB data, more like 5-6mp. When you scale down from 16mp you will likely achieve better results because of this.

At very high ISO's you may find that the 8mp camera will outperform the 16mp even considering the interpolation factor.
 
The issue is further clouded by the fact that the Nikon D70 has a CCD (Charge Coupled Device) type image sensor, while the D7000 has CMOS (Complimentry Metal-Oxide Semiconductor) type image sensor.

What is the benefit? I've never really researched it. All I know is that the original Canon 1D had a CCD and could reach shutter speeds of something like 10,000 or 100,000, because the shutter was....electronic? When the shutter speed was changed it just changed the duration of the electrical charge sent to the sensor?
 
I was just reading this article today by CNET.

CCD (charged-coupled device)
Currently the most common type of digital SLR sensor. Almost every dSLR manufacturer offers at least one CCD-based model.
Pros: Traditionally, the highest image quality, pixel for pixel. Current sensors include innovative chip architectures designed to enhance dynamic range or speed.
Cons: Most expensive. Most power-hungry.


CMOS (complementary metal-oxide semiconductor)
Initial implementations took advantage of CMOS' on-chip electronics to make cheap but noisy sensors. Stripping off the extra circuits increased each pixel's light-collecting area, thereby boosting sensitivity and quality to surpass that of many CCDs.
Pros: Theoretically, lower production cost. Uses less power than CCD.
Cons: CMOS sensors tend to be bigger than their CCD equivalents, resulting in larger cameras.

The bottom line on sensor types

Ignore the theoretical claims and judge the cameras, not the sensor types. We've seen great photos--and crummy ones, too--from digital SLRs with every technology.

Link: http://reviews.cnet.com/4520-7603_7-6241014-3.html

The issue is further clouded by the fact that the Nikon D70 has a CCD (Charge Coupled Device) type image sensor, while the D7000 has CMOS (Complimentry Metal-Oxide Semiconductor) type image sensor.

What is the benefit? I've never really researched it. All I know is that the original Canon 1D had a CCD and could reach shutter speeds of something like 10,000 or 100,000, because the shutter was....electronic? When the shutter speed was changed it just changed the duration of the electrical charge sent to the sensor?
 

Most reactions

Back
Top