Colours - we all have our preferences and that's perhaps why there are so many colour filters that can be applied in photo editing applications. Every camera manufacturer will offer various colour filters, whether that's Fujifilm or Canon or Nikon, it really doesn't matter because it's you that will ultimately choose what you like. Industry 'standard' filters are also offered by Adobe and are specifically tailored for portrait, landscape work and more...
We all perceive colours differently, so a red rose to me may not look exactly the same through your eyes. So why, if colours are so subjective, does white balance matter?
To answer this we need to understand that natural daylight falls in the temperature range of 5000 to 6000 kelvin (or an average of 5500 degrees kelvin) depending on the time of day and condition of the atmosphere (clear days have a 'cooler' light than overcast skies). So if you take a photograph outdoors using your camera's automatic white balance settings then your white balance should hopefully fall somewhere in this range. However, your camera may not always get the white balance right, it will usually be a little off and as a consequence there will be a colour shift in your image. Resulting colours in your photograph will not be at the right starting point, or put another way, they won't be standardised with respect to the lighting conditions. Once you have an accurate white balance you can do what you like in editing, warm the image up or cool it down, saturate the colours more etc. However, starting from the right white balance will help ensure you avoid unwanted colour casts that can affect your image, and when photographing people it's important that skin tones are accurate. The subtle changes of colour across the human face are important and it's very important to realise that just a small change in the wrong direction really matters if you care about your photography. The colour cast may not be readily seen until you make the correction and then the unwanted hue becomes apparent when compared against the corrected image. In the end a white shirt should look white if the white balance has been set correctly. In fact skin tone, hair colour, clothing and make-up will all be more true to life and be representative of the colours you saw on the day you took the image.
Like many photographers, I have often let the camera make an automatic judgement of the white balance for me (and I am still happy to do this). If the setting was way off the mark then I have made adjustments in editing applications like Lightroom or Capture One, to ensure that unwanted colour casts were removed before I started to further edit the image. This is all fine and for most of us it's usually 'good enough'. However, when shooting client portraits (in other words, photography in controlled conditions) I like to ensure my white balance is as accurate as I can get it and to do this I will use a white balance target.
A quick google of 'white balance targets' will show you a miriad of grey or white looking cards that can be used in post processing to change the white balance. They can also be used at the start of the photo shoot to set the white balance correctly in-camera before the photography session starts. Using them is not too difficult and I'm not giving a tutorial here but instead I would encourage anyone who is serious about their photography to make good use of a high quality, spectrally neutral, white balance target (reflecting an equal amount of red, blue and green light).
The image above shows my colour chart from X-Rite - the 'Color Checker Passport'. This rather expensive device offers dedicated white balance targets for portrait and landscape use as well as a colour palette that's used to create a calibrated profile for use during ediitng. The bottom chart is used by software to make a new filter specifically for your lighting conditions. The bottom left small white square can also be used to set white balance which is usually a little cooler in temperature compared to the dedicated row of 5 portrait targets seen in the top half of the passport. Why so many white balance targets I hear you ask? Well in this case X-Rite have created a set of 5 landscape and 5 portrait options which you choose according to preference in the amount of warmth you wish to add to your image (or remove). There is even a larger more 'neutral' target on the back of the passport (not seen in the image) that closely matches the little white square on the bottom left hand side of the colour chart. All this comes in at around £110 in the UK. The tiny colour squares are protected within the plastic case and the colours must not be contaminated with oils from your fingers or dirt of any kind, as this will affect the filter profile that is generated and will spoil the result. In other words.... don't touch the colours, they are delicate and meant to be kept in pristine condition.
If this is too much for what you need then simply purchase a white balance target that is spectrally neutral and non-reflective. There are plenty for sale and range from as little as £10 or so to over £100. Choose wisely, because in the end you get what you pay for...
Below the identical images differ only in the white balance. One was set using the calibration chart and one shows the white balance which was set automatically by the camera. Now, if I didn't tell you which was which, you may be undecided as to which you think is correct. However, I know how the colours were meant to look and can tell you that there is a marked difference in accuracy, the image on the left is more true to the colours than the one on the right.
Both lie within the range of 5000 - 6000 degrees kelvin, the one on the left is warmer with less of a magenta tint when compared to the cooler image on the right, they are around 500 degrees kelvin different in colour temperature.
As a standalone image, either of these may suffice as a portrait but only one really shows the true colour of hair, make-up, skin, clothing and background. The one on the left is the more accurate and this is important from the photographer's perspective. If an image goes to print or is used commercially then the colours need to be right.
In the end you might judge that the image on the right is good enough and indeed some people may prefer it. However, going back to what I said at the start, colour perception and choice is a very personal thing as we all perceive colours differently. It's my view that when it is important to do so, we should calibrate our images before deciding if we should make any preferential 'tweaks'...