My favorite function in modern DLSRs

You are either a regular of this blog, or a new reader. If you are a regular, you might want to take a sit because what I am about to say will hit you hard. 

So I got a D600. First because traveling with a Mamiya RZ 67 is impossibru. Also I wanted to work on my digital skills, get better at architecture and cityscapes, and therefore, practice a lot. I have been using it for a few month now, and I realized that one function on this DSLR turns out to be an absolute must: the built-in HDR.

- "Amagaaaaad Ronan you hate HDR and digital stuff! what da hell is this contradicting nonsense ! I worshipped you and fed from your every word and now I am as confused as when Ricky Martin made his coming out !*"

- Here we go. Well, dear follower, this is not at all what I wrote in previous posts. Let me remind you of my position on digital and HDR:

• Digital is great, and complementary to film. It convenient, fast, powerful in bad conditions, so much better than analog for many many things but...
• ... film as a dynamic range like no digital sensor ever had, try velvia 50 and see for yourself.
• Film allows very large films / sensors from 60x70mm and larger, which with corresponding lenses leads to systems capable of stunning results, although fairly cumbersome to use.
• B&W film looks better due to a more linear and rich range of tones and nicer looking noise.
• The overly abused use of extreme forms of HDR is the photographic equivalent of Nikky Minaj. It's ugly, vulgar, and can cause the tasteful man to cry blood. 
• HDR was intended to compensate the lack of dynamic range of digital sensor, not to make pictures look like a clown's face.
• Come on Ricky Martin was way to well groomed to be straight !

So no I don't hate digital stuff. Yes I prefer the crafting of analog and mostly the feel of images due to dynamic range and B&W rendering, but I also love my digital camera; it just depends on what I'm shooting and where.

No I don't think HDR should be left aside, I think it should be used in order to compensate the physical limitation of digital sensors. And here is my point: the built is HDR function on the D600, and I am sure on any other advanced DSLR, allows a rendering of colors and light that I find very very interesting with minimal effort. If you are not using it because you are afraid it will look like that:

What is that? the next Call of Duty? 

Well change your mind, you must try it in high contrast situations. It leads to things like that that I find very mellow and subtle. This is what HDR used in a more classic way looks like:

- "Hum...Ronan, this is not HDR. It looks totally übber normal to me. Nice composition by the way."
-  Oh thanks! Indeed dear reader. It does, and that is precisely the point. As I said before, digital sensors suffer from poor dynamic range, which is the capacity to render both bright and dark areas of a picture correctly. In other words, you often have the choice between:

• exposing the shady areas well, but the rest is burned out
• exposing the bright areas properly, but the rest is all black

Digital cameras, especially in ISO higher than 400, get pretty poor at that (FYI the best sensors for dynamic range are the ones of the D800, D4 and D600, in that order). It can suck pretty bad on a sunny day.

Interesting fact, what a lot of people like about the image feel from digital Leica M cameras is precisely their good dynamic range. Simply most viewers have a hard time putting a name on it.

Used wisely, that is to say when necessary, it really leads to beautiful landscapes. Yes landscapes only, it still does take 2 pictures and you need a steady subject. I prevents you from having to use graduated filters, which is a pain, or do manual HDR at home on PS.

So when do I use HDR with my D600:

• high contrast landscapes, on bright and sun shinning days.
• ISO above 400 when dynamic range falls appart, even if contrast is not so high
• when I wont need to process the image much, because you can't shoot HDR in RAW. 
• I use +/- 2 stops in general, but it's good to play around
• Not for action shooting or portraits, I find that portraits deserve to make a choice on how to expose your subject, but then again, it's a matter of taste.

Anyway, I hope some of you who never use this, because you wonder what that's for, will now benefit from that great function. Now go out and take pictures !

PS: some exemples of film images with good dynamic range. Notice how darker and brighter areas are rendering with good level of details. Dimensions appear more as a consequence of depth of field rather than exaggerated shades.

Courtesy of Lefty.

*Visualize a Family Guy-like funny flashback of your own creation.

D800 rating #1 at DxOmark

...what the hell is DxOmark?

DxOMark is "the trusted industry standard for camera and lens independent image quality measurements and ratings. "


In other words, if you wonder how your sensor performs against an other, and argue online based on your visual interpretation of  a 1:1 crop, give it up, check DxOmark, close the debate. Then you'll be able to stop counting pixels and do some actual photography :)


Now wait, if I despise pixel counting, why am I mentioning that ranking? Answering this question requires asking an other question: why do some people still shoot film? Well among the reasons, film has a much superior dynamic range than any digital sensor. That is simply an awesome property and one of the reasons I shoot mostly film no matter what. It means you can shoot a high contrast scene and both dark and bright zones will come out with a proper level of exposure. Beyond the technical talk, it just makes photographs way more subtle, refined, colors are nicer, and landscapes in particular looks a zillion times better. Digital photographer use filters, or HDR (high dynamic range) to simulate the better dynamic range of film. 


But now, look at this: 

At ISO100, 200 and 400, the D800 offers even better dynamic range than a D4. This + 36MP + built in HDR mode make it the best landscape SLR you can which for. Of course, any large format camera will destroy it, but for digital, it's good stuff. It overtakes the D700 all the way, and only the D4 ranks better from ISO 800 and above.


Every camera is best at something, for large prints plenty of light shots, or long exposures, the D800 is your friend. 


Oh and according to the ranking, the D800's sensor doesn't only overtake the D4, it also is ahead of the 50000$ Phase One IQ180MP best of the best digital medium format camera... So i'll say it: when I heard about the 36MP, I was like "yeah right...crap". I was wrong.

An explanation on digital sensors size, and what it means for your pictures.

When buying a digital camera,  2 things require your attention: the lens, and the sensor. I'll write the next post about the lens, but for today let's focus on the sensor.

A bit of context first: image quality, appart from your talent, comes from the optical characteristics of the lens, and the characteristics of the sensor. Now with film, the sensor is the film, so the chemical characteristics of the film at the contact of light are responsible for the tones, noise, dynamic range of your image. 

When shooting digital, instead of photons hitting film, you have photons hitting a sensor that will send an electric signal, according to how many photons of a given "color" he receives (physics PhD please forget my vulgarisation).

Enough theory, my natural geekiness would quickly bore many of you. My point here is : the lens is like the chassis, the sensor is like the engine. Everything else (LCD screen, buttons here and there) are just options and they should not be the main things to look for.

I talk about sharpness, noise and dynamic range as variables of your image quality. Let's first see what they mean, then we'll see how sensor size impacts those variable, and for those who just want the final word, I invite you to skip to the end for conclusions :-).

• Sharpness is about image elements being distinct from one another. In other words, can you clearly see where something ends. It has nothing to do with resolution! Resolution is how many pixels you can count on the picture, the size of the image if you prefer. You can have a huuuuge resolution and a totally blurry image at the same time. Now sharpness is nearly 99% under lens influence, so don't get confused by bad salesmen bull-shitting you with mega pixels. If you care about sharpness so much, you can get a fix lens, but mostly you should start reconsidering your approach to photography :)

• Noise corresponds to sensors (or film) made so sensitive to light that they even see light when there is none. Those inaccurate dots on your image are what we call noise. We push a sensor to be ultra light sensitive when we want to shoot in low light. That sensitivity is what you change by raising ISO. The higher the ISO number, the more sensitive, the more noise the sensor is likely to generate. If you see that a camera goes up to 12000 ISO...well that means nothing. The noise level might be so high that image quality would be awful anyway. Also one thing to keep in mind: film noise can look real nice, when digital noise can be properly awful.

Ilford 3200 ISO film on a 6X7 camera (huge sensor equivalent): gives it a nice looking grain.

• Dynamic range is a little trickier to explain. Let's use an example: I'm sure you already took a picture of some one in front of the sky, and the sky came out totally white. Or the person is coming out black and the sky is blue, and you can't see no details at all on the subject. Dynamic range is the maximum difference between dark and bright that your camera can handle. It's terribly important for landscape in particular, because a valley, a snowy mountain and the sky can have very different brightness level. With poor dynamic range, you only have one part correctly lit, the rest comes out all white or all black. Ever wondered what HDR is? It's when you take several pictures of the same thing, at different light exposure, and pile up picture to make sure everything is lit properly. It's nothing more than faking very large dynamic range.

Courtesy of http://kimletkeman.blogspot.com/ on this image you understand how DR can be important: you want the shades and the far right part to still be detailled, not just one of the 2.

Ok now back to today's topic: how do sensors impact those image characteristics?

To cut corners a bit, the bigger the sensor the better. 

With film, portrait is done with medium format, up to 60x90mm size film. Landscape is done with large format cameras with even bigger film surfaces. 

What we call a 35mm film camera (24x36mm) is the pocket format, the film equivalent of a compact, the low quality stuff...And that's what we call full frame in the digital world! The top of the range Canon 5D's and Nikon D3 and D700 are "only" 24X36 sensors cameras, also called FX. 

- Most DSLRs are DX camera's, not even a full 24X36 sensor. They are 17X25mm sensors also called APS-C. All the Nikon D3100, D5100, D90, D300, Canon 7D, 550D and other are DX cameras.

- Compact cameras have even smaller sensors. Rather than going thru each of them, look at the characteristics of the camera you're into, and see in the table below what is the sensor size:

Sensor size is crucial to noise and dynamic range for a simple reason: the bigger the sensor, the larger the pixels for a given picture size. 

For example, compare a 10MP medium format (MF) camera with a 10MP compact : same amount of pixels, but the MF camera's sensor has a surface about an hundred time larger. The pixels are then a hundred times bigger. Each pixel being bigger, it can rely of a much larger amount of light hitting it to gather information: it is more sensitive in low light, and generates less noise as it doesn't take decision out of very little amounts of light.

Same with dynamic range: the pixels need less exposure to collect the proper amount of light in the dark areas of you image. So while they get exposed for brighter parts of the image, they still receive enough information to obtain detailed dark objects.

Last but not least: depth of field.

DOF is the distance between the nearest and farthest sharp object on your image.

Long story short, the smaller the size sensor, the more DOF you get. It means that small sensors, i.e. most compact cameras can hardly blur the background behind your subject. Not that it is a necessary thing to do, but it limits your creativity by prevent you from exploring a key variable in photography.

One way of allowing less DOF (=more blur behind) is to have lenses that open very wide (those F1.8, F1.4 lenses), but few compact camera offer that, if any.

Very little DOF: you will NEVER be able to do that with a compact due to sensor size.

If you are into portrait, don't spend 500$ in a premium compact! Get a used Nikon D90 or Canon 550D with a 50mm 1.8 lens, for about the same price.

CONCLUSION

- The bigger the sensor the better

- Bigger sensor = capacity to shoot in low light

- Bigger sensor = image with better exposure, details in dark zone, which is crucial for landscape

- Bigger sensor = the possibility to get a very sharp subject with a very blurred background, ideal for portrait.

Let's force manufacturers to stop making those mini sensor cameras, when you buy GO FOR BIGGER!!! 

My choice? The only compact with a bright lens and a APS-C size sensor (same as most DSLR) is the FUJI X100. Otherwise go DSLR.

The upcoming Fuji X10 will have a smaller sensor, so careful with the appealing feature, the X100 might still be the best camera for you if you shoot more portraits !

This being said, a rubbish camera can still pull the best picture in the world. So go out and shoot whatever you have :-)