Grain versus Noise

I've been playing with some of of my images and converting a few to B&W. Back in the day, I remember we often embraced the grain in B&W images. Now, when I look at my digital conversions, which I personally like, I worry that what I interpret as the look of "grain" is just noise. If that is indeed the case, is there a time when digital noise can actually be aesthetically appealing in an image versus a technical flaw? I've attached a sample of one of the images I am working on. I'd like to know what you folks think. "Digital grain" or just noise?

Karen

Tricky ain't it ?

First of all I never took many pictures pre digital ( and none in the water ).

But I confess a love for B&W images.

FWIW ( and trust me that is not a whole hell of a lot ) the look of digital noise is no where near as nice as film, somehow it is sharper and tends to be more aggressive somehow.

I have used and loved Silver Fx Pro from Nik Software - while _all_ of the available effects can be emulated in Photoshop it is a hell of a lot easier with some of the custom tools, and the ability to compare side by side images is great.

For me - I found I like the look of Tri-X 400 which I have never used in the film version at all.

If you like B&W then it may be worth trying some of your images in the trial version of some of these tools for yourself.

Paul C

BTW - I like your image but reckon that it could use being pushed a bit harder in the hilights and shadow areas and adding of some grain.

Paul

Thanks for the recommendations. I will download the trials and play around. The thought of a Tri-X 400 filter makes me swoon. I used to love that film!

Karen

Digital noise is ugly. I hate it.

Grain in an image can be a feature.

Noise and Grain have different appearances. There are plugins that add the look of grain. There are plugins to remove noise. I've never used the "add noise" command to make an image look better.

I like your conversion very much.

Paul

 

Thanks for the recommendations. I will download the trials and play around. The thought of a Tri-X 400 filter makes me swoon. I used to love that film!

 

Karen

Karen,

I visited your website and I like very much your raggies shots. Where is spot?

Damien

Karen,

 

I visited your website and I like very much your raggies shots. Where is spot?

 

Damien

Raggies??? I'm just going to venture a guess that you are referring to the Sand Tiger Sharks. Did I guess right? Those were all taken in North Carolina which has some of the most incredible diving on the planet. Great wreck diving with lot's of Sharks, huge schools of baitfish, big Amberjacks, schooling barracuda...well, that's what we call them on THIS side of the ditch!

Okay, so you say noise looks very different than a "grainy" look. I still don't know how to tell if I've overprocessed it. Could it be that the noise in the background water may be apparent in the color version but look okay in black and white?

Could it be that the noise in the background water may be apparent in the color version but look okay in black and white?

Oh yea - you can push B&W a lot further than colour before you end up with banding or posterization issues.

Colour noise can also often be smoothed out a lot in say LAB mode - by smoothing the A and B channels (this works well for both B&W and colour images).

Noise in the L (luminance) channel is a bit more tricky to shift.

In the wreck image - was it taken at high ISO ? or is the 'noise' just crud in the water ?

Often hi ISO images have dominant noise in only one of the colour channels (most often the blue ) which is why the LAB smoothing stunt works.

Difficult for me to see without the raw image.

Paul C

I'm pretty convinced that noise and grain are very different and agree with all the above. I think noise does much more than give a grainy look to the image it also degrades the image with loss of tonal gradation particularly in the shadows. This is why I am not an adherent to the proposal that one can overcome the apparent noise by simply increasing MP. Unlike grain which tends to display more evenly across the tonal range, noise is disproportionately more evident in darker and underexposed areas. Grain pattern, when used appropriately, I think can enhance the atmosphere of an image. I agree with Paul, play with Silver FX and see which way the image looks best to you.

Maybe someone has an old (shot on film) black and white underwater image that they consider to have attractive grain?

It may just bet that tastes have changed?

Maybe someone has an old (shot on film) black and white underwater image that they consider to have attractive grain?

 

It may just bet that tastes have changed?

I think you have a point Alex. I do think noise is really more degrading and less attractive to the image. I used to intentionally create highly grainy images, studio portraits etc pushing Tri-x to 1600ASA or more and using some of the specialty high speed films at 6400ASA. I think the best way to describe it is that grain created a more even textured appearance of the photograph which was sometimes the intention. Even today, if I wanted to create that appearance I would do it with one of the filters using a low noise image, rather than creating a high noise image. Another aspect is electronic media. Grain in an an image on a monitor, does not impart the same textured appearance one gets in a print. I'm not sure either how grain transfers from an inkjet printer vs the old darkroom approach, I really have not compared, never having scanned negatives and printed them on my inkjet.

In the wreck image - was it taken at high ISO ? or is the 'noise' just crud in the water ?

ISO was 400. I think what I'm seeing is crud in the water. Some of that got better when I converted it but when I bumped up the contrast it sort of reinvented itself in the water areas. I think making a good print will definately help me decide.

Thanks everyone!

One thing you may also want to look at in your black and white conversion is your channels. See which is the cleanest and use channel mixer accordingly to get the cleanest B&W conversion. When using Silver Effex, one of the sliders that can increase the appearance of noise or crud in the water is the Structure slider and one may need to back off on this, but then lose local contrast. And a last approach I can think of if you want to work at it is to selectively reduce noise or even use Gaussian blur in areas like open water, by using masks in Photoshop.

400 ASA with a D300 should not give you noise - unless you under expose and then try and reclaim the situation by pushing the exposure during the RAW conversion.

So it is likely crud in the water and the way forward is as Loftus suggests.

Would like to see some posts of BW film with grain as per Alex suggestion.

In fact I may start another thread and see if anyone has some images.

Paul C

TMax 400 pushed to 1600 (ex HMAS Hobart)

TMax 100 pushed to 400 (Harasti inside the J4 sub)

Coolpix 5000 at 800 (May have done some noise reduction)

This is not quite what the doctor ordered, as it's a monochrome conversion of a 1600 ASA Kodak negative shot with a Nik V:

Tim

And this is a digital mono shot under similar conditions this year, about 2 miles away from the previous image:

I've left the files on the large side to try and avoid adding compression artefacts to the inherent noise (you can call me pedantic, if you like, but grain is noise, although it has different spatial and luminance properties to digital noise).

Tim

I'm just going to embrace the noise...oh! I meant Grain

Hey Karen,

If you have some time download the new beta version of Lightroom 3. (free) They have added a grain slider in the develop module which mimics the look of film grain. You can add "grain" as you like and play with different effects. The new tool lets you control the amount of grain and the size and roughness. (LR Terms) To my eye grain and noise are very different things, though I hate to disagree with Tim . If you'd like to see a good explanation of the grain slider in the new version of Lightroom there is a nice video here. It's in the first video at the 17:00 min mark.

Have fun,

Steve

I am not so sure that Noise and Grain are different .. i think they are just two different term one for film and one for digital.

I think the trouble has arisen from digital images being noisey at the start to the point of being bad quality with nothing the user could do to change the outcome.

With film as we can see from examples and anyone that shot it .. the photographer chose to push the film to create an effect (or just to get AN image). When digital came along noise started from the sensors not being able to pick up all the information (is how I always perceived it) and the photographer often had little control over the noise.

I think that has changed as the tech has advanced and now we can push our images (sometimes it's a bit harder to do so, as i have experienced with my 5d2). If the tech keeps improving the only way to get grain or noise will be in post processing !

(mostly just brain farting out loud there but i did have a penchant for bw film when i started and always loved pushing it to get a desired look)