Now, there is a new kid on the block, top of the food chain, Japanese crown jewel, the best what camera world can offer. Well, at least 35 mm world to be precise, because it could upset some medium format system owners. Anyway, the all new Nikon D4 is here and there are two questions to be answered. Firstly, how already insane ISO 102400 can be raised up to 204800 and still be useful and secondly, where Nikon get that idea to replace two top models with only one flagship, because it sounds a bit let's say familiar to me.
Unfortunately, as I have no idea about one of them (ISO) and have only small suspicion about the other one and it actually might not be true, I am probably not the right person to waste your time with the answers to that. Well, here is the third question then and that is how different (read better) is D4 in comparison to D3s. Of course, as every new release in every industry it'll be faster, smarter and everything, but let's have a closer look to the main features.
New D4 is taking 16,2 MP to the megapixel race with the competition against 12,1 MP in D3s. Sensor is exactly the same size in both cameras (36 x 23,9 mm), what is logically making one pixel smaller in D4 (7,3 micro metre) than in D3s (8,45 micro metre). Pixel size can look like a WTH??? information, but in fact is quite important, because the bigger the pixel, the more light sensitive it is, which means it can memorize more light data and at the end it is creating better images and that is all what matters. And that is a pub argument tip why your mate's 15 MP compact is not even in the same sport than full frame DSLR.
Maximum picture resolution is 4928 x 3280 in D4 and 4256 x 2832 in D3s. More is still better. And nothing is better than more fps, in fact D4 can make 10 fps in full frame format and you can even talk it to the 11, but you must lock your AF on your first frame, where D3s was capable of 9 in FX mode, or 11 in DX (cropped) mode. They both have 51 AF points.
ISO range in old D3s was normally 200 - 12800, boosted form 100 to mentioned 102400, where D4 can do bottom 100 as a standard to 12800, which can be boosted to 50 at the bottom and 204800 at the top. It will probably create some desperate looking pictures, but desperate times call for desperate measures and if you'll ever need it, the possibility is there.
Dimension-wise, the D4 with 1180 grams is 60 grams I was going to say lighter, but I'll say less heavy than D3s with 1240 grams, even though it's a bit bigger - 160 x 157 x 91 mm for D4 against 160 x 157 x 88 mm for D3s. So let's sum it up.
Let's start with the probably biggest change against D3s and that is D4's video ability. D4 is capable to do a 1080p full HD video at 24 fps now, where D3s could do only 720p also at 24 fps, which was quite a handicap against competition.
Changes from still shooting point of view are not that dramatic, but picture quality was quite impressive in D3s anyway. Of course, there are tweaks to make it even better, such as new 91.000 pixel metering sensor instead of 1.005 pixels sensor in D3s. This sensor is not there just for metering, but it will do the subject tracking, white balance and it also allow you to do "face detection" shooting through the viewfinder. It also has got improved AF system called "Nikon Advanced Multi-CAM 3500FX" with 51 AF points. Now if you'd like to ask where the difference is, because same thing was in D3s, I'll give you a hint. There is no "Advanced" in D3s system. And if something is not advanced, it won't focus every one from 10 pictures you'll take per second with D4.
To make sure everything captured at the speed will be also precessed at the speed, there is new EXPEED 3 image processor, which will send data do the completely new high speed memory card technology called XQD. No, you don't have to trash you CF cards, D4 will take those as well. Thanks to that D4 will do 100 RAWs or 200 JPEGs at one burst, where D3s is far behind with "only" 40 RAWs, or 130 JPEGs.
And that's about it. Nikon with D4 improved what was already a standard in its class and by adding an HD video, Nikon has erased the gap against its rivals.