Sensor explanation

[JR1]

Sensor explanation, BUT I disagree again with the comment that people may "upgrade" from crop to FF, rubbish, each camera is different, horses for courses I don't believe a FF camera is an upgrade.


http://www.digitalcameraworld.com/20...-cool-effects/

[NorthernFocus]

That's not a very well written article. The part about DOF is really poorly written. The author doesn't seem to understand the topic.

And the part about technique is just rubbish. Pixel COUNT isn't the issue. Pixel density is more the point. I'm always amazed how people go on about perfect technique being needed for the D800/810 but never say a word about the 24MP DX bodies that have much higher pixel density. I guess there is a point if you are taking the same FOV with both. Then yes the higher MP requires better technique.

[Brownbear]

I wonder if someone could address/explain this in simpler terms...

What’s wrong with more megapixels?

A full-frame, 35mm DSLR has a fixed amount of real estate upon which to place its photosites, the tiny electronic light-catchers that add up to a camera’s megapixel count. On any given sensor not all photosites are created equal, but for simplicity sake, it’s enough to know that one photosite equals one pixel, so a 36 megapixel camera has 36 million photosites. Light enters through a lens, hits a photosite, where it’s measured, digitized, and stored. Bingo, a digital image is born.

Sensor technology continues to evolve, allowing more photosites and improved image quality with each sensor iteration, but for any given technology, the fewer the photosites (lower megapixel number), the better the image quality. That’s because the only ways to add more photosites to a fixed sensor area are to shrink the photosites and/or cram them closer. A larger photosite collects more light than a smaller one, making it more efficient. And the farther apart the photosites are, the cooler they stay (heat is the enemy of pretty much all things electronic).

There are advantages to a higher (mega)pixel count—larger prints, being the most cited benefit. A higher pixel count also increases your margin for error, enabling photographers to compose wide and crop later. But image quality is not one of those advantages, and in fact, the vast majority of photographers (including pros) don’t ever come close to needing the pixel count their cameras deliver.

Until the consuming public figures this out, megapixels will continue to sell cameras and camera manufactures will continue stuffing more onto our sensors. But look no further than the $6,000 Canon and Nikon flagship pro bodies to understand that pro photographers jumped off the resolution escalator long ago: Canon’s 1DX is 18 MP; Nikon’s D4s is 16 MP.

It's a quote from http://garyhartblog.com/2015/02/19/m...are-overrated/

Thank you.

[xpatUSA]

I wonder if someone could address/explain this in simpler terms...

What’s wrong with more megapixels?

<blah>

It's a quote from http://garyhartblog.com/2015/02/19/m...are-overrated/

Thank you.

I'd love to help, Christina, but the article is written in a language which I call "Photographic Vague" (PV).

No details, no math, no links - just verbal opinions. Which means that any simplification would, of necessity, be equally vague and equally useless.

Sorry,

[Manfred M]

Christina - another article that is rather misleading and in some cases totally incorrect.

First of all image quality has a number of "drivers" that are not even mentioned; colour depth, dynamic range in addition to things not at all related to the sensor; sharpness (out of focus parts of the image that shouldn't be or motion blur where none is warranted), lens resolution (lens quality plus of course the fact that large apertures tend to produce some softness and small apertures result in diffraction). A dirty lens or poor quality filter will also decrease image quality. The main advantage of larger sensor pixels is better low light performance.

Of course he totally misses the point that good lighting is very important to getting a good picture...

The comment regarding electronic noise is not correct. Yes, a warm sensor is part of the issue; but the fact that a higher level of amplification is required from smaller sized pixels is the key driver here. I don't know if a larger pixel sensor runs "cooler" or not; I'll leave that to the electrical engineers on this site to comment on. He also ignores noise introduced by other parts of the camera's circuitry and current leakage issues.

The last paragraph is also total nonsense. When the D4 and D800/D800E came out, Nikon was quite clear that the two cameras had two completely different audiences; the D4 was aimed at low light and sports / action photographers and the D800 was aimed at studio / portraiture and landscape photographers. The writer completely discounts the mechanical and electronic issues required for shooting at higher frame burst rates.

Unfortunately, Christina. The author really does not understand the subject he is writing about particularly well.

[Manfred M]

. Then yes the higher MP requires better technique.

Yes and no to that one Dan.

The performance of any system is generally limited by the weakest component in the system (Engineering 101?).

In a smaller pixel count sensor (assuming fixed sensor size), the sensor performance is the limiting factor on image quality. Lens issues and poor technique are hidden by this limitation.

Take exactly the same shot with a higher pixel count sensor and all of a sudden, the limiting factor has changed as some other factor is now the limiting factor; likely technique (unless you are using a particularly horrible lens).

That all being said, the other issue that comes into play is the degree of magnification. We only magnified to a certain level with the smaller pixel density sensor, but will go to higher levels with a larger one. We will see the new limit purely because we are "pixel peeping".

[Brownbear]

Thank you Ted and Manfred, with an extra special thank you to Manfred for a wonderful explanation.

Indeed reading this article gave me the impression that the Sony As7 would be the ideal camera for landscapes. Lightweight for hiking along with great image quality, a great dynamic range and low light capabilities. Truly appreciated.

[chauncey]

IMHO, as I've said before...the key advantage of a cropped sensor lies in it's utilizing only the centermost/sweet spot portion of your lens. Observing any lens's MTF characteristic makes it
overtly obvious that the image IQ begins to deteriorate toward the edges of that lens.

Manfred touched on the myriad of other problems affecting those crop sensors that,
if they were somehow corrected, the ensuing product would be one superior camera.

It would be interesting to see the results of one of those high MP behemoths with the
image cropped down to a cropped sensor size compared to that of a image from a
cropped sensor of equal generation.

[Manfred M]

IMHO, as I've said before...the key advantage of a cropped sensor lies in it's utilizing only the centermost/sweet spot portion of your lens.

Not entirely true; this assumption can only be correct when you assume using a full-frame lens on a crop frame sensor. If you get a crop frame lens on a crop frame sensor, the image circle will be designed for that specific sensor size and any advantage of using light from the centre part of the lens will disappear.

[chauncey]

Oops...knew that but that ole memory lapse thingy kicked in.

[Manfred M]

Christina - there is no such thing as an "ideal camera".

Another Engineering 101 statement; the design process is all about managing the various tradeoffs to get you to the final product.

The camera was obviously the "right" choice for the author of the article, who seems to do a lot of low light photography. It would not be my ideal camera, just because of my investment in lenses that will not work on that particular camera brand.

In my case, the right choice may be driven by what I'm doing, more than anything else. Do I want to take my large full-frame camera and three pro lenses along when I'm out trekking for 12 hours or would I rather take something light weight with a small all purpose lens along? Would I use a camera phone when I'm doing a studio shot, or do I bring out my Ff camera?

Just because someone suggests something is ideal for his or her use, doesn't make it better (or worse) for someone else.