Opposed to this is the photo here where the colours on the photo are more neutral and don't show as much so a pencil or charcoal portrait might be best from this photograph.
 

In this photograph the skin tones look similar all over the face so again maybe a pencil or charcoal portrait would be best.

This photo has plenty of yellow ochre in it and would make an excellent pastel painting. To sum up if you have a neutral toned photograph with very little colour in it then a pencil or charcoal drawing might be best or if you have a photo that has one or two colours in it then a pastel painting might work well.

I know that some people prefer one medium over another and this is fine, it doesn't mean that a colourful photo wont make a good pencil or charcoal portrait, the same is true of a black and white photo that it probably would make a good pastel painting. When there are certain qualities in a photo like the babies blue eyes then it makes sense to have a coloured painting to bring out these attributes. These are general guidelines and if you wanted a colour portrait from a black and white photo and you know the colouring of the person's face then I can paint a pastel painting from your photo.
 

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