Tuesday, June 22, 2010

Noise Control

In the good old days of film, we worried about "grain"; film grain! We demand "fine grain" film, we processed our black and white film in fine grain developer to achieve finer grain!

Came digital and instead of grain, we are face with "noise"; digital noise or image noise.

Unlike film grain which can usually make your picture look sharper and create more impact in black and white photos, digital noise make picture look awful!

When I was working with the papers, Kodak Tri-X was my "standard" all round B&W film. I shot all type of subjects with just one film type and often exposed at ISO 400 to 1,600 without worrying about graininess of my images!

"The Birdman of Penang" was shot on Kodak Tri-X 35mm film rated at ASA 800 (or ISO to you), dunked in Kodak D-76 developer.

100% crop from the picture above.

Grain? What grain? Those were the good old days of film!

Fast forward 1976 above to 2001, we were at May-N's graduation ceremony in Wellington. Three years before I was shooting all digital, on that important night; the Rm 120,000 Kodak DCS 560 DSLR that Kodak Malaysia so kindly loaned me... DIED without warning!

I was forced to shoot with my tiny Canon G2 compact! Take a look at this shot taken by a friend with the G2!

Aaarrrhhhh!!! That my friend, is DIGITAL NOISE galore!

Compare that to this shot taken with the Kodak 560 before it gone kaput.

Noise free, smooth rendition of tone and colour from the 6 mega pixel FULL FRAME DSLR!

What did we learn here?

The LARGER the image sensor in the camera, the better it can eliminate or control noise! The diagram below put the size of both sensors in perspective.

Size DOES matter!

Of course, apart from CCD/CMOS sizes; there are other conditions that can also influences the noise performances of a digital camera.

A quick search in Wikipedia under image noise harvests the following content!

Go into it if you like but you might like to know how I get rid or minimise image noise in my shots by using noise filters?

Lets take a recent shot as a test shot to compare the THREE noise filters I acquired through the years :)

Sim Hock, was taken at his London home not long ago. The Olympus E-P2 contain a CMOS sensor EIGHT times larger than the G2. And yet at ISO 640, you will see quite a bit of noise if you make a 200% blow-up.

The 200% crop.

Here are the results, noise filters were applied to the FULL image before the 200% crop was cut out.

I bought Noiseware Pro more than 5 years ago, look like it is still going strong!
I did not muck around with the settings, I selected "Portrait" (top left) and OK; it gave a very smooth result but a dab soft on the fine detail.

Like Noiseware, grand daddy of noise filter; Noise Ninja has come a long long way! I remember fondly when I was trying it out way back in 1998!

the best feature of the Ninja is how easy you can profile the noise in your image and after that just hit OK! Presto, it is magic ;)

New kid on the block, Denoise 4 from Topaz Lab made plenty of claims; their interface (look at all those sliders!) will make any tinkle-gig scream with delight! I find the adjustment a bit heavy handed. You really need great patience to "reclaim" some of the detail that the noise remover took out. Be careful of artifacts if you are the slider happy type ;)

So which one I like best?

First, they ALL WORK! Each got its own strength of removing different type of noise, overall; the Ninja is the easiest to use! The Pro version which cost US$ 79.99 is the same price as Topaz Denoise 4. Noiseware Pro is $10.00 cheaper at US$69.95.

Famous Last Words:
Before you bonk your hard earned cash for noise control, it cost you nothing to download all the trail copies and play with them until you decide!

If you are using the latest Photoshop CS5, compare the built-in noise filter in their Adobe Camera Raw; I know it is quite basic but it can do a pretty good job at removing noise too! May be that is all you need?

The noise filter in ACR, pretty powerful stuff!


1 comment:

heather said...

However did they coin the phrase "noise",, for graininess?When I first heard that phrase in relation to photography, I thought it was so odd, I looked it up into the dictionary,