Friday, January 15, 2021

New Year's Resolution

From a "year in review, year in preview" piece at Luminous Landscape came this interesting digression on the rumored imminent ultra high resolution sensors: 
"It is difficult to tell a really good 24-26 MP print from a 45-60 MP print at 16×24” – it’s possible, but under close inspection – even an experienced observer would have a hard time on the wall. A 24×36” print from a really good 24-26 MP sensor and lens looks good on the wall, even in a gallery – but put it next to a 45-60 MP version and the difference is obvious from close up. I’ll happily print 40×60” from a Z7 or an A7r IV, which I won’t from a good 24-26 MP sensor – like a 24×36” from 24-26 MP, the print works very well, but if you put your nose right up to it, you might wish you’d used a GFX 100 or stitched. A 90-100 MP sensor will really show its stuff at a print size of 40×60” or above – the native print size of the GFX 100 sensor is 29×39” at 300 dpi, and a beautiful print that big can be made from a 200 dpi or even 150 dpi file with careful resizing. How much of your work ends up that size? Do you have room for a printer the size of a piano? If you are thinking about digital display, what 12K display device are you planning on using? Even at 8K, it has no advantage over a 45-60 MP camera, since both will outresolve the display. 

What lenses do you own that will resolve 100 MP? What will even look different between 60 MP and 100 MP? An Otus, sure… Some of the best Sigma Art lenses, like the newish 85mm f1.4, are likely to. A few other excellent lenses – think the best of the Sony G-Master, Canon L and Nikon S lines, mostly primes. Any exotic long telephoto prime from Canon, Nikon, Sony or Sigma. If any zoom that good exists at all, there are VERY few of them. The closest possibility I’ve handled is Nikon’s 24-70mm f2.8 for the Z bodies – it resolves right up to the limits of the Z7 and seems to be begging for more. I’m pretty sure it has at least something more to give on a higher-resolution sensor. I haven’t used the latest Canon or Sony zooms at the top of their lines, nor have I used either of the $10,000 telephoto zooms – but they all seem to be good candidates as well. That’s about it – a bunch of $1000+ primes, mostly $2000+ other than the Sigma Art lenses, and a very tiny list of $2000+ zooms. 

How good is your technique for 100 MP? Even the best lens is only that good at optimum aperture – diffraction is going to set in quickly with pixels that small. Handholding will require faster shutter speeds than you’re used to, even with image stabilization, and any subject motion at all is going to show up. Depth of field? What depth of field? The 45-60 MP cameras are already difficult to focus correctly, since any tiny focus error eliminates their resolution advantage. If you’re doing huge prints of architecture or motionless landscape, using a Series 3 or larger tripod (think 6-7 lbs of tripod and head, even in carbon fiber) or have enough light for very high shutter speeds (any noise at all will kill the resolution advantage, so a very high resolution camera will be best at ISO 64-200, maybe ISO 400 at most to see the difference), you might see a gain. 
Speaking as someone who sold her 5D Mark II to partly fund a mega-super-high-res 5DS and then wound up buying another used 5D Mark II to supplement it, all I can say is...ouch. 

Sure, the 5D Mark II is about a dozen years old now and sports a 21MP sensor, less than half the resolution of the 5DS, but it'll turn out a photo that can be splashed across a full two-page spread eleven inches high and eighteen inches wide, with plenty of room for the art director to crop...

Shot with a Canon EOS 5D Mark II and an old EF 28-70mm f/2.8L lens

The 50MP sensor on the 5DS will let you know a lot of things: If your lens sucks, if you missed focus, if you should have used a stabilized lens or a faster shutter speed or more light. Cramming that many photosites on a full-frame sensor is noisy at higher ISOs, at least in Canon's 2015 effort.

From a gee-whiz point of view, I get the attraction of a squillion megapickle camera. But from a gearhead point of view, I have to acknowledge that its downsides currently outweigh its upsides for the kind of shooting I do.