histogram

How to Read a Histogram
If you’re a photographer, or a regular user of the levels command in Photoshop, you’ll be familiar with a histogram. Photographers know how to read the tone of the shot from it, ensuring the right balance of shadows, midtones and highlights. Users of the levels command will tell of a similar use, but rather than it balancing out the tone before a photograph, they’ll tell an equally important story of using it once the photograph is taken and the image downloaded to their computer. Yes, the story of post processing.
 
Removing a Colour Cast using Levels Video Tutorial

A colour cast is when the colour of an image shifts towards a specific hue, say green, to give the whole image an unsightly green tint. The reasons behind this and the resulting cast can be as numerous as the tools available to fix it. For this reason we'll take a classic example and put things right both manually and automatically.

RGB Histogram Video Tutorial

Photoshop produces red, green and blue histograms inside an RGB image, when it's done it puts the results into a composite version and displays it as the standard view. How that composite view is calculated decides how we see clipping inside our images - and as you'll bear witness, things aren't always what they seem!

Advanced Histograms Video Tutorial

It's time to summarize the RGB, luminance and Colour histograms available inside Photoshop, and talk more specifically and indeed more technically about the statistics available in the expanded view. It's not necessarily about how to ask questions, it more about deciphering the often misunderstood answers that the histogram palette is shouting out!

Improving Skin Tones with CMYK Values Video Tutorial

With one foot inside the CMYK colour space but the other firmly rooted to RGB land we begin to harness the power of number-based skin tone adjustments using the colour sampler tool and the levels command. Altogether a more involved but highly rewarding way to work that's employed by studios and portrait professionals around the world.

Improving Skin Tones with RGB Values Video Tutorial

Modifying skin tones can be a tricky task, thankfully within levels we have a number of fully-adjustable yet simple techniques that wield some great results. Some of these results depend on the user’s perception of what's right, or what's wrong, with the colour of the skin, other results are aided by a library of skin tone swatches that are prepared to work overtime to get you the results you demand.

Finding Shadows and Highlights with Levels Video Tutorial

So we know what shadows and highlights are, and we also know a way of locating and using them in conjunction with the relevant eyedroppers - but surely there must be a more accurate way of finding the brightest and darkest pixels inside an image? Well I'm glad you asked, as with assistance from the threshold command, the colour sampler tool, the info palette and the eyedroppers we can achieve pinpoint accuracy in a modest amount of time.

Setting Black, White and Grey Points in Levels Video Tutorial

The eyedropper tools inside levels have the ability of setting specific values for specific pixels which is ideal when adjusting shadows, midtones and highlights. In the honour of levels we'll look at the eyedroppers and the theory of posterization followed by a full blown creative party as we play with those aforementioned eyedroppers, avoid the party-pooper that lives by the name of colour banding, and perform a very special party trick by transforming the grey eyedropper into a colour replacement tool. Doesn't time fly when you're having fun!!

Neutral Colours and Adding Saturation in Levels Video Tutorial

The term 'neutral colours' will feature a lot in the latter stages of this video series, so it's important to form an understanding of what it means - and how it can help us keep our colours accurate and true. On the other hand, adding saturation is the act of taking the colours, or more accurately the hues of an image, and making them more vivid by raising the intensity level - which is yet another level to understand!

Levels Adjustment Layer Video Tutorial

In the world of non-destructive image editing with the levels command - the adjustment layer is king. Sitting at the top of the layers palette it gracefully and parametrically controls every pixel below it, and when used in combination with its equally powerful ally the luminance mask it becomes a true Photoshop force to be reckoned with.