Image Quality (IQ). It's what every photographer wants/needs.
Chris's comment on this is brilliant.
No, not all photographers crave better image quality. I'm content with Micro Four Thirds—it gives me all the quality I need, considering my subject matter, lighting conditions/environments, and output media. Anything more than that is just a waste on me, really, and would force me to carry heavier equipment than necessary. For others that line of sufficiency may be with APS-C, others get that with smartphones; for Ming Thein, though, it's in Medium Format.
In that regard I was intrigued by the recent splash Hasselblad made by releasing news of its new compact,
Compact? Is it, really?
http://j.mp/297pm81
Sure, it's a lot smaller than the Medium Format digital cameras we've had until now. But I still wouldn't call it "compact."
mirror-less 50 MP medium format digital camera, the X1D. For beginners like me, if you don't already know, medium format digital cameras have significantly larger sensors than so-called full-frame digital cameras.
"Significantly larger" depends on what you compare the difference to. Medium Format is not just one size, it's like a family of sensors, where there's a variety similar to Four Thirds, APS-C and 35mm (Full Frame). In fact, MF has its own "Full Frame" size, and the X1D's sensor is far from it—actually, it's the smallest of all MF sensors, measuring approximately 44mm x 33mm.
Correct me if I'm wrong, but the term full-frame refers to the frame size of 35mm film and is currently the largest digital sensor offering by many major camera manufactures such as Canon, Nikon, Sony, et. al.
Right. And Pentax.
35mm was basically the smallest film photographers used back in the day. There were smaller formats, but they were a lot less popular.
So, I was wondering if the 50-megapixel medium format X1D by Hasselblad can/will deliver better image quality than the 50-megapixel Canon EOS 5DS / 5DS R (for example)and the comparable 42-megapixel Sony Alpha 7 RII, both of which have smaller full-frame sensors. (BTW, if anyone could provide the exact measurements of each senor format's length and width, I'd appreciate it for the sake of comparison.)
The dimensions are written in the specifications of any camera on this site. Just search for one in the text box at the top of the page.
Is there a limitation to the full-frame sensors that isn't apparent to me? Would the larger 50 MP medium format sensor be expected to deliver better image quality, or would the smaller 50 MP full-frame sensor deliver the same IQ?
To put it another way: would an image produced by a 50-megapixel sensor be expected to have the same quality no matter the size of the sensor itself that produced it? Is the size of the Hasselblad's X1D medium format sensor overkill? Can the same IQ be produced by smaller full-frame sensors with an equal number of pixels?
Think of it like you'd think of any pair of different sensor sizes with the same megapixel count. Only the difference in size is even smaller. You probably know the crop factor between APS-C and 35mm is roughly 1.5x or 1.6x. From Four Thirds to 35mm it's 2x, so from Four Thirds to APS-C it's about 1.33x. The crop factor from the X1D's sensor to 35mm is 0.79x, or the other way around: 1.26x. So you can see that the difference between the 35mm format and the X1D's sensor size is smaller than the difference between APS-C and 35mm, and slightly smaller even than the difference between Four Thirds and APS-C.
What comes to your mind when you think about image quality while comparing sensor sizes? It's not some magical thing, it's comprised of things we can measure and pinpoint to, like dynamic range and noise in low light. Normally there's about a stop differentiating APS-C from Four Thirds, and about a stop differentiating 35mm from APS-C. So it's fair to say the X1D should be better than 35mm by less than a stop. That means, if you can shoot with a 35mm camera comfortably at ISO 6400, you'll feel the same about ISO 10000 or thereabouts on the X1D.
That's assuming an "all else equal" situation, and that's never going to happen.
One thing we can always compare is lenses. Currently, there are only two lenses announced for the X1D: 45mm f/3.5 and 90mm f/3.2. To get the same shot on a 35mm as you'd get with these lenses on an X1D wide-open, you'd need roughly a 35mm f/2.8 and a 70mm f/2.5 (rounded the numbers a bit). You can get that with a 24-70mm f/2.8 zoom, or have a wider aperture with primes and, you guessed it, either option is cheaper than buying both Hasselblad lenses.
Who might see better "image quality" with the Hasselblad? Ming Thein, obviously. But on a more serious note, you'd have to use the camera in an ideal situation—set it up on a sturdy tripod, stop the lens down to its peak sharpness point, and use the base ISO. That's where you'll get the best image quality the system is capable of. I don't think we know what the base ISO is yet, but it's safe to assume it wouldn't be any higher than 100. So the only camera that might match it entirely in terms of noise at base ISO is the Nikon D810, at ISO 64, assuming the Hasselblad's base ISO is 100. But we're splitting hairs here; the number of people in the whole world who need this subtle improvement is very close to zero.
OP, I hope you managed to understand what I wrote here. I wrote this as it flowed in my chain of thought, so it might not make a whole lot of sense to a beginner. My suggestion is simple: Don't worry about it. That's a $9,000 camera you'll probably never own, so no need to trouble yourself with it. Go out and take pictures with whatever you have, and if you need anything else, get what you need, not what's available.
