Is DX dying?

[island911]

Glen said Megapixels alone do not make the sensor good. The pixel density on a full size sensor is not nearly as high as the small sensors. The large sensors just have more area to do the same work.

That was the context.

IOW, if a FF sensor array is doing the same work (capturing the same image) as a smaller sensor array, then it will be further back (lets assume same megapixels and a pin-hole camera from the same physics closet as the massless ropes and frictionless pulleys)

What you are talking about is the advantage of using existing lenses to get a larger image. ..or that you've been dragging around lenses too big for your existing sensor. That's different than saying that a larger pixel works less.

[nostatic]

DOF is another consideration - the larger the sensor, the easier it is to get subject isolation. In addition, for a give resolution a larger sensor will have larger photo sites which can lower noise. Everything is a compromise - from size/weight to sensor manufacturing yield, to ergonomics. You can make great images and crappy images from most any modern camera. As the market stands right now, there are a spectrum of sensor choices, and those systems (the larger ones) are accompanied by a spectrum of lens choices. As I said before, cell phones have pretty much killed the small sensor (e.g. 1/2.3") market. While those compacts still are on the market, they have been declining rapidly due to the proliferation of cell phones. The still viable choices are:

1" (Sony RX100/RX10 series)
u4/3 (Olympus/Panasonic)
1.5" (Canon GX)
APS-C (and slight variations - consumer dSLR like DX)
FF (also called FX)

At this point both 1" and u4/3 seem to be holding their own. The 1.5" sensor is a reasonably new entry. APS-C has been around for a long time, FF has as well and now is starting to compete on size and price with APS-C. One problem with FF is that the sensor requires better glass, especially as you go to higher resolutions. The optics on a consumer zoom lens found on a kit APS-C dSLR won't cut it on a FF sensor. So typically you end up with much bigger, heavier, and more expensive equivalent lenses for FF. You can easily to the other way (depending on mounts) and use FF glass on crop body with no penalty.

There are sweet spots for individual users. It is more about how you shoot and what your final output is than a set of tech specs. If you're publishing stuff on the web, most any camera will produce acceptable output. If you're printing large, a bigger sensor will typically have better results (all other things being equal). If you're shooting available light, typically a bigger sensor will have better results. If you're pushing files around in post you typically want very high resolution and as many bits and pixels as you can get. If you are shooting sports you may be worried about AF and burst speed which can be better on an APS-C dSLR (depending on the model).

If you want some good opinions, this forum has people who actually shoot for a living along with gear freaks: getDPI | Photography at its best. I avoid dpreview.com, fredmiranda.com, and many of the other large enthusiast sites because they are full of trolls and people who obsess over specs and never shoot (other than brick walls to test their gear). Well, if that is your sort of thing, then go for it though. I admit that I've shot a few brick walls to test new lenses for any decentering problems. But beyond that I don't find it a compelling subject

[winders]

Originally Posted by island911

Glen said Megapixels alone do not make the sensor good. The pixel density on a full size sensor is not nearly as high as the small sensors. The large sensors just have more area to do the same work.

That was the context.

IOW, if a FF sensor array is doing the same work (capturing the same image) as a smaller sensor array, then it will be further back (lets assume same megapixels and a pin-hole camera from the same physics closet as the massless ropes and frictionless pulleys)

What you are talking about is the advantage of using existing lenses to get a larger image. ..or that you've been dragging around lenses too big for your existing sensor. That's different than saying that a larger pixel works less.

I am not even sure what your point is. You can get the the exact same image on a full frame sensor as you do on a crop sensor. You just need the appropriate (longer) focal length. The sensor would not be "further back" and the camera would be in the exact same location so the perspective would be identical.

Regardless of the lenses used, full frame sensors have technical advantages over crop sensors. The two primary advantages are low light performance and dynamic range. Both of these are directly tied to the lower density of the full frame sensor. If you are working the wide angle end of the lens spectrum, lens quality is seriously better in the full frame camp. The only real disadvantages you can associate with full frame sensors compared to crop sensors are cost and lack of reach.

[wdfifteen]

^^
"lack of reach" ??? 'splain please.

[nostatic]

The crop sensor on DX makes your lenses have a longer apparent length. A 200mm lens will give a shot that is framed like it came from a 300mm lens. That doesn't mean that you really have a 300mm lens - it is still 200mm but the results will look like 300mm. A u4/3 gives you a 2x conversion so a 200mm lens will look like a 400mm. This is one reason that nature shooters tend to prefer APS-C and u4/3 - longer effective (but not equivalent) reach.

One way to get around this is that a FF sensor likely has higher resolution so you can crop and get roughly the same result.

[winders]

Originally Posted by wdfifteen

^^
"lack of reach" ??? 'splain please.

Sure. I'll use Nikon in this example.

The crop factor for the Nikon DX sensor compared to a Nikon FX sensor is approximately 1.5x. So, if you put a 300mm lens on a DX camera, you would need a 450mm lens on an FX camera to get the same image on the FX sensor.

In other words, for a given focal length lens, you get more reach with the DX sensor or less reach with the FX sensor.

[island911]

Originally Posted by winders

I am not even sure what your point is....

Clearly. Too simple a point, apparently.

Originally Posted by winders

You can get the the exact same image on a full frame sensor as you do on a crop sensor. You just need the appropriate (longer) focal length. ....

Sure.

To simplify, imagine a pinhole camera...

Any given field of view thru that focal point contains x lumens.... Those lumens can be 'projected' to a sensor array, or negative, or even a wall. The total amount of light passing is constant thru that field of view, but the lux is not. As the 'projection' behind the lens widens, the lux drops off. So, you can either have intense brightness on a small sensor array, close to the focal point, or a proportionately less brightness on a larger sensor array, which would have to be further from the focal point. (which one is better for low light situations?)

So I am just saying that bigger sensor elements is not a very compelling reason to go to a FF camera. Besides, if you get the FF then you'll just be jonez'n for a medium format 60Megapixel Hasselblad. :-/

[winders]

We aren't working with pinhole cameras so your example is not relevant.

It is a simple fact that larger sensors offer advantages over smaller sensors in terms of low light performance and dynamic range.

[island911]

Originally Posted by winders

We aren't working with pinhole cameras so your example is not relevant. .

Ok, so physics isn't your strong suit.

[winders]

Originally Posted by island911

Ok, so physics isn't your strong suit.

...and the fact that a sensor is not a wall seems lost on you.

Larger sensors with less pixel density offer higher dynamic range and better high ISO (low light) performance compared to smaller sensors. There is often less noise too.

Digital Camera Sensor Sizes: How it Influences Your Photography

[slodave]

DX is good for birding, as was mentioned, because of the ability to crop in. I have a D300 as a primary DSLR. My dad has the D800e. Even though the D800 is FX, with the 36MP, you can crop really close and not lose detail or sharpness. Although, they are years apart technology wise and that makes a difference as well.

[Scott Douglas]

Originally Posted by winders

This site is much more accurate and useful:

Cambridge in Colour - Photography Tutorials & Learning Community

Thanks for the link. Very nice site.