Monday is gear day. Earlier last month I wrote about what hardware to use to post process images (you may click on one of the notes on the left side bar in the main blog roll to find other tech related articles). The answer to the question which hardware to use is generally as always: It depends.

It depends what you want to do with your images, it depends how many images you‘re going to process at once, it depends on image size or Megapixels involved and it depends how much time you‘re willing to spend on waiting for the computer to process your files.

In my case I need my laptops professionally, for example for weddings. The faster the computer the earlier you‘re finished, the earlier you can move on to the next thing and do something else.

When you‘re working with hundreds of files, f.e. when I come back from a wedding I usually bring back 2.000-3.000 images, computer power becomes a necessity to not be annoyed. I was processing a wedding at the beginning of 2011 with a 2007 MacBook Pro with 4GB of RAM, this wedding took me a couple of weeks, simply because the computer sometimes needed minutes to import files from Lightroom into Photoshop as it had to swap to its slow hard drive most of the time.

If you want everything to run smoothly you will want the best components possible. For example I‘m using a 2011 MacBook Pro with a Quad Core processor and 16GB of RAM. Those specs are very useful when working with Lightroom because it uses a lot of memory for it‘s library. Importing into Photoshop needs processor speed. 

But to put it into relation modern computers and laptops are generally fast enough for everything but the most demanding jobs where you need to process hundreds of images at once. I bought a new MacBook Air for travelling and blogging on the go, especially for my big trip from October till December. It‘s Dual Core i7 processor is actually not noticibly slower than my Quad Core when processing individual images, it takes something between 6 and 10 seconds to import into Photoshop from Lightroom. What‘s really great about the new Haswell generation of processors is their battery life. I sit in the kitchen now with full sun behind me on the balcony. Display brightness is 50% and battery should last another 15 hours when only typing or lightly browsing the web. That means I can also sit somewhere outside in the park and blog from there and not run out of battery on a whole working day. Sweet!

For maximum performance, though, you will want as much memory as possible. For me 16GB is enough, when extensively working with Lightroom the 8GB of the Air are not enough, I found the laptop swapping to disc the other day slowing everything down sicnificantly, even though it has the fastest SSD flash storage on the market at the moment. For big jobs you still need the biggest computers possible.

Why do I use Mac? Well, I‘m sure you‘re totally fine with a PC as well. I was fascinated maybe 8 years ago when a friend just connected to our Wifi-Network with his MacBook within seconds, something that used to be impossible with a Windows machine. I‘m using Mac for 6 years now and to be honest I never ever had any software related issues, my Macs just get my work done with no hassle. I‘m also heavily invested in Mac software, so it's not really that easy to go back to Windows. I am saying this although I really had some nightmares with hardware and Apple Service. Both my MacBook Pros have replaced logic boards now and they have been to workshops endlessly. Still, when hardware is fixed they work flawlessly, never crash and get their task done. Everything just goes ...

But I strongly disagree with Apple‘s policies and the way they‘re dealing with workers in China, especially at Foxconn. I just read another article today claiming bad conditions at one of their main suppliers in China. The bad thing is, there‘s not really an alternative, all other tech companies are producing in China as well, at Foxconn or other doubtful factories.

We can only express our disapproval and beg them to finally establish better conditions and treat people the way they deserve, human ...

Let's hope the best, till next time, happy processing

KIKI

It was a blast, weather was amazing, the couple looked gorgeous and it was a really great day. I hope to finish the whole set at the end of this week ...

coming soon ...

KIKI

Hi there, first I have to say that I changed plans a bit because I will sometimes not be able to stick with the topic to the exact same day every week. I found it especially impossible to write legal articles without my books at hand, for example when I'm travelling. So as this blog focuses on photography there will be some weeks where I post more articles with new photos and those related to cameras and techniques. I will try, though, to switch to society and law in other weeks therefor a bit more.

Today I want to talk about digital noise and why it is important to modern photography. First of all, what is digital noise? Digital noise appears in digital photos sometimes when there is not enough light available, mostly in dim situations or at night. You can easily spot it in a photo as colour blotches and grittiness, the images is not as clean as those photos taken in bright daylight.

Why is it that way? You can compare digital noise to the grain in film photography. The bigger the grain in film was, the more sensitive it was to light, so the dimmer the surrounding could be in which you were going to take a sharp photo in. In digital cameras the film is replaced by a digital sensor of different sizes, actually a silicon chip with millions of little pixels, themselves comparable to the grain in film. Film sensitivities are expressed in ISO values, that's the same in digital. The higher the number the more sensitive now the digital sensor. ISO values normally alter in doubling steps, f.e. shooting in daylight is perfectly fine with ISO 100 with every possible camera. ISO 200 f.e. is double the sensitivity of ISO 100, so you can shoot with half the available light or with double the shutter speeds. It's getting interesting when you need to change to settings of ISO 1600 and above, because then big DSLR have a clear edge in image noise. But are the pixels getting bigger, too, like the film grain with rising sensitivity? No, they stay the same size, the higher sensitivity is achieved by amplifying the signal the sensor reads out from each pixel that collects the light. Complicated? Well, it's actually quite simple. Compare it to an audio amplifier. When you had a really muted recording on a Compact Cassette you had to increase the volume of the amplifier, that way the noise was getting louder, too. With a digital sensor it's the same, when you have only very little light available and recorded by the sensor, it needs to be amplified a lot. That way all steps during digital image processing that add noise to the image get amplified as well, for example the noise from the circuitry of the sensor, from heat, base noise levels and more.

Put simple, the lower the light the noisier the image. What can you do about it? First, to be honest, noise has never really been a problem for me, in film more grain could even add some atmosphere to the image and I find myself delibirately adding grain afterwards to an image that was clean in the first place. People are different, though, and there are situations where noise is not desired, for example in the church when you shoot the wedding couple kissing. It's always great to bring back clean images from situations you wouldn't have thought they were possible. Still, it's always a question of personal acceptance. Higher sensitivities also allow for higher shutter speeds, needed to freeze people's motions. Shooting in a dark room without flash you need very high ISO values to retain fast enough shutter speeds to not get blurry images. Image stabilizers for example let you shoot stationary subjects with longer shutter speeds but they can't help when shooting people in dim light.

On the other hand it really depends on when you find noise in an image obtrusive. Women often don't care about things like noise and I have to agree, when you take a great photo its noise levels become secondary. Still, easy things to consider when chosing a camera and lens combination to shoot people in dim light are: The bigger the sensor the lower the noise levels, DSLRs have sensors sometimes 10 or 20 times larger than a normal point and shoot. I show you what I mean. The following images are taken with a premium compact, a Panasonic LX7, that has a bigger sensor than normal compacts (7,44mm vs. 6,17mm) and a DSLR, a Canon 5D Mark III with a sensor 21 times bigger (36mm). Both where shot at the same shutter speeds, aperture levels and a very high sensitivity of ISO 3200. The above image is from the point and shoot, the lower one from the DSLR ...

And here are the two at a pixel level ...

As you can see you get much cleaner images with a big camera. But you can also make great images with a small one, it lies in the eye of the beholder. To give you a perspective I will shoot the Canon with an ISO level of 25600, 8 times more sensitive to light, have a look how they compare now ...

Noise levels are quite comparable with the 5D being sharper because it got more pixels. Referring to noise this means you can shoot with the same shutter speed in light levels 8 times darker or you can shoot with 8 times the shutter speed in the same light levels, here a 1/400s with the LX7 and a 1/3200s with the 5D. Pretty cool, huh!?

Second very important thing to consider for noise free images are fast lenses. Most zoom lenses already start slow and get even slower when zooming in. By slow I mean the shutter speed needed to let in the same light to the sensor. Those zooms often start at an aperture value of f/4 and slow down to f/5.6. What does that mean? Well, I will talk about shutter speeds and apertures another time but imagine the aperture of a lens as the pupil in the human eye, the smaller the pupil the less light gets in or the lower the light the bigger the pupil gets. It's the same with lenses, different lenses have different maximum aperture values, slow zoom lenses being quite dark. When you shoot in dim light you need slow shutter speeds to compensate for the little light coming through the lens, thus you get blurrier images of people or you need to increase the ISO level and get noisier images. Take a fast prime lens and you get more light to hit the sensor, that way you can retain fast enough shutter speeds to freeze people's motions or/and need a lower ISO level and get less noisy images. For example when you zoom in your zoom lens to shoot a portrait your lens aperture becomes a quite small f/5.6 at 55mm. Take a 50mm prime lens, that only costs 120 €, you get an aperture value of f/1.8. That's over three times the aperture value compared to the zoom, means over 8 times more light comes through the lens, you may shoot in 8 times lower light levels with the same shutter speed or you can shoot with 8 times the shutter speed in the same light. This gives you the ability to shoot with lower ISO levels and still get faster shutter speeds to stop motion. For example, when you shoot your slow zoom at 55mm f/5.6 with ISO 3200 in a bar your shutter speed could be a slow 1/30s, too slow to freeze motion and also too slow to compensate for camera shake. If you put on your 50mm prime and shoot at f/1.8 you could alter shutter speed to a 1/80s, fast enough to freeze motion in portraits and fast enough to compensate for camera shake. And you can set the ISO down to 800 and still get the same bright images as with the zoom with much less noise in it. Cool, eh? So, if you don't like noise, buy a camera with a big sensor and a fast lens and you're set to shoot in dim light without flash.

Alright, now you should understand what digital noise means and what effect it has on your images.

See you next time

KIKI

Hey,

actually I wanted to show you some real world samples that will give you a good impression of how the various focal lenghts give a different look to the image. Starting with 12mm up to a very compressed 200mm at the end.

Have look ...

Both 12mm capture a huge amount of the surrounding scene ...

My favorite focal length of 24mm captures plenty of the scene, putting you right into it without being too wide ...

35mm is said to be the best documentary focal length, letting you keep a distance but being wider than a normal 50mm ...

I use 50mm on weddings a lot, it's pretty intimate, focussing on the subject, capturing much less of the surrounding scene ...

The above two images are 105mm tele and 200mm tele respectively, compressing the scene quite a lot with the subject being in the focus ...

I will show you some more images soon ...

Have a fun week,

see ya

KIKI