Why Ever Invent Cropped Sensors?

[D-B-J]

What I can't figure out is this: The lenses I used to shoot with when I had 35mm films cameras are much smaller and lighter than the lenses used for Nikon DX format. I've come across some of those lenses I sold many years ago and they look absolutely puny!

Are the wide aperture lenses? Now a days, an expensive FX lens has many pieces of glass, mainly to cut down on aberration, diffraction, and all those shenanigans. I think, basically, they've improved significantly. And to improve, they need to be bigger.


Now, i have no facts to support that, so someone please feel free to answer more accurately. These are merely my guesses.

 

[Garbz]

What I can't figure out is this: The lenses I used to shoot with when I had 35mm films cameras are much smaller and lighter than the lenses used for Nikon DX format. I've come across some of those lenses I sold many years ago and they look absolutely puny!

Actually my experience is completely the opposite. My DX lenses are far smaller than their FX equivalents. My girlfriend's 4/3rds lenses are smaller still. Compare apples to apples, after all better design tools have allowed for lenses with more elements to be more easily calculated. I'm not surprised that the modern lens is more complicated, but the modern FX is still larger than the modern DX.

I mean, we started with 35mm film, now DX sensors, and recently, a movement back towards FX sensors. So what was the point?

You missed two critical bits, firstly we didn't move from 35mm to DX. APS existed a long time before digital ever did. Also it wasn't just cost. What photographer would accept a camera with a defect out of the box? The cost is not only in area, but also in sensor yield. If you have statistically a certain amount of errors per area of a wafer then it becomes physically quite hard (and thus expensive) to create an FX sensor. There have been major advances in increasing yield over the last 15 years so and the cost differences between the sensors has been reduced as cameras have come down in price.

Cost is just the application of supply and demand. Supply being the hard bit to achieve. That's why you go for smaller sensors.

 

[usayit]

The manufacturers of the sensor chips can make more crop sized chips out of a single wafer than larger full frame.

 

[Ant]

What I can't figure out is this: The lenses I used to shoot with when I had 35mm films cameras are much smaller and lighter than the lenses used for Nikon DX format. I've come across some of those lenses I sold many years ago and they look absolutely puny!

Because although DX lenses are naturally smaller they then stick extra stuff in them, like AF-S and VR which makes them bigger again