Just when we thought we'd seen it all in the "Megapixel Wars", Canon unveils two 50MP full frame cameras in the form of the 5DS and 5DS-R. Previously, Nikon had held the top spot for DSLR resolutions with it's thumping great 36MP beast found in the D8xx series cameras.
While these high resolution sensors may sound great (and indeed I own and love the D800) what are the real benefits and indeed, the drawbacks with having such high megapixel images?
First lets look at the benefits. The most obvious is the size of the resulting photographs. The 5Ds will be producing 8688 x 5792 pixel images. Comparing that to the D810 with its 7360 × 4912 and my somewhat antiquated D90 with a 4,288 × 2,848, the new Canon will allow for some pretty gargantuan prints to be made and still retain a great amount of detail. We're well into medium format resolutions, although depth of field and crispness still falls short of a true MF sensor camera.
Next is the ability to crop in. If there is a certain area of a photo you want, having sensor resolutions capable of heavy cropping and yet still retaining a good level of sharpness and detail can be important. That's one thing I enjoy about the D800 and something I found I suffered with a bit on the D90. If I cropped heavily on an images shot with the latter, things started to become a bit "grainy" for my liking. Still, if you framed your shot well to begin with, then it wasn't an issue but, having the ability to crop in is certainly a nice feature to have in the bag.
Detail. Yes, if you're a pixel-peeper and like editing down to the pixel scale, you will love a large resolution camera. Open up a RAW file inside Photoshop and you can just keep zooming and zooming and zooming to make minute changes. Not something that appeals to everyone but, certainly this has its merits for meticulous digital retouchers and artists out there - although I've already seen some shuddering at the prospect, haha!
Now we draw our attention to the negatives associated with super high resolution cameras. Right off the bat is - resulting image sizes. Yes, the very benefit I mentioned at the top of the article is also a drawback! Huge resolutions means huge RAW files, which equates to bigger memory cards. That 16GB class 10 card you had in your 18MP camera will not last 2 minutes under the weight of a 50MP sensor. To get a decent level of storage (and I favour using multiple cards so as not to put all my RAW/eggs in one basket), you're going to need to look at the 64GB and above cards. Did you see what I did there? Raw eggs....? Never mind. They'll also want to be relatively fast writing too because, if you're racking off the shots quite quickly, you're going to need to write a lot of data to the card. Big cards (although memory has come down in price over the years) are still quite expensive. Then again if you have £3k to drop on a camera body, £150 on a few cards probably isn't something you'll worry about too much.
Carrying on in that vein of thought, we have to consider permanent storage of those RAW files too. Large file sizes means those multi-terabyte hardrives will get filled up relatively quickly, if you're not ruthless with you final selection. While hardrive storage is relatively cheap in the grand scheme of things, you may find yourself needing to look at something like a Drobo or similar network storage device after a while, to accommodate the files. I find nothing more irritating on my computer desk than wires and cables running everywhere. I already have 3 USB drives and am short of USB ports on the motherboard and plug sockets to power them as well.
Along with storing your RAW files, will be your software editing files, like Photoshop PSDs. When I edited multiple layer images on RAW files shot with the D90, I used to consider 400MB a "big" PSD file. When I jumped from the 12MP D90 to the 36MP D800, It wasn't uncommon for my PSD files to hit anywhere from 1-2GB in size. So again, storing PSD/PSB files will require a lot more storage space, especially with a 50MP sensor.
In order to edit those massive RAW files, you will also require a high performance computer to handle the task. A powerful CPU and at least 16GB of RAM (preferably 32GB), as well as a decent GFX Card. A solid state drive is also a must as even 10'000 RPM traditional hardrives are a bottle-neck in the system these days. A dedicated scratch-disk solely for Photoshop would also be a good idea. If you don't already own a well specified computer, then expect to pay a minimum of about £600 for motherboard, CPU, RAM and GFX card of decent quality - that's if you can re-use your existing chassis and power supply unit. If you don't already have large capacity hardrives, add another couple of hundred. I run 2 x 2TB drives mirroring one another as a fail-safe.
By now you're already seeing how high resolution cameras can work out to be pretty expensive, just in additional equipment outlays. The bad news is, it get's worse too!
The last drawback is in the lenses. To get the full benefit out of these megapixel monsters you need top quality glass. For example, lets say you want to crop in heavily to one area of an original photo, because you love the expression on someone's face. If you used a bog standard lens which itself lacks high resolving glass, then the resulting crop will be soft. Canon knows this and is why they have launched their new 11-24mm f/4 lens alongside the 5Ds for the bargain price of £2800! Yes, that's right, I didn't miss a "." in there. It's £2800.00!!
So what does this mean? Well, if you currently own a prosumer camera and wanted to step up to the 5Ds, if you only have kit lenses in your bag and perhaps a few mid-priced primes, they probably aren't going to cut the mustard on the 5Ds if you want to make full use of the cropping. If it were me, I would be looking at the Sigma 35mm and 50mm f/1.4 Art lenses and nothing short of the 70-200mm f/2.8 IS II, with a macro/portrait lens thrown in there for good measure. In short, you're looking at about £3k in glass as a minimum in most cases. That's on top of the £3k body
When we actually stop and think about all this for a moment and put things into perspective, are the benefits real? And I say this quite genuinely because, for the most part, they are not. Very few professional photographers, let alone amateurs or enthusiasts, require resolutions this massive. Unless you are having your work blown up on billboards, or used for a client who demands it, then chances are you only ever display your images online. Uploaded to Facebook, or perhaps photographic forums with 800px limits, compressed in jpeg format. You could of course upload them to Flikr at full resolution but, you can't see them anyway at that size. Viewers are limited to their screen displays. My 23.5" monitor is 1920 x 1080. Even if you have something like a Dell 27" screen, the resolution is still only 2560 x 1440. It can't display 8688 x 5792 photographs, so the images you upload have to be compressed to be viewed anyway.
If you do print stuff out, chances are they're going to be 8x10 prints, or maybe a large canvas at most. I printed an 80 x 40cm canvas from a cropped in file taken on the D90 with it's seemingly paltry 12MP sensor and it was beautifully detailed. So from the evidence presented, we can see that for most photographers, this megapixel marketing being sold to us, is for the most part, sheer madness. It's beyond the scope of all but a few photographers out there and you need some serious dough for the lenses, computer system and storage to get the most of out it.
Fanboys may read this article and think I'm bashing Canon. I'm not. I don't do the brand-loyality bullshit. I'm not butt-hurt that Canon produced a higher resolution camera than Nikon. If there are better cameras and lenses out there that aren't Nikon, I point them out without hesitation. Period. The article applies as much to the D800 as it does the 5Ds in terms of glass, cropping and computer hardware. Ultimately, you need great glass for both cameras to get the full potential and if you aren't cropping in often or doing huge prints, then it's total overkill.
We have hit the peak for what the overwhelming majority of photographers require in terms of resolution. What I would like to see from camera manufacturers is a global/electronic shutter to enable faster sync speeds to control ambient light. Focus more on increasing ISO performance. Lowering of native ISO. Focus systems and increasing FPS for the resolutions we currently have. You know, things that are going to bring real world benefits to everyone!