Cliche, I know, but the eyes are indeed the window to the soul.
In any portrait whether human or animal, get the eyes wrong and there will be no life.
We are magnetically drawn to look at the eyes, so generally I would suggest painting them first. Afterall, if you muck them up you will have wasted very little time; you can turn your paper over and start again. If you wait to the end and are really pleased with how it’s gone and you think ‘ooh I’ll just finish off with the eyes’ and then you muck them up, well you have wasted hours and are setting yourself up for a whole pile of frustration. In my opinion…..
A few things to think about – they are not called eye balls for nothing – they are spherical and not just buttons popped on the head. There is a film called Cajoline (I think) which used to scare my kids silly, and that centred around eyes being replaced with buttons in a parallel world. Ick. Also they are set into the head and not on the surface, so there are shadows from the brow bone to consider. They are wet, so you need to capture that liquidity. And finally if both eyes are identical and equally strong, we as the viewer get a bit confused. We don’t know which to look at first. Try to make one slightly more dominant and each just a tiddy bit different from each other. (I got that tip from a Jean Haines workshop years ago, and it is very true).
Birds’ eyes, like a robin are pretty straight forward, but when you get to owls and mammals they are more complex and need to be built in a few steps. This is an owl’s eye, so it has a good stare on it. The principle for a mammal is just the same.
Stage one is painting the iris in. I paint all over except for a highlight. If you paint round the pupil you will get an edge you don’t want. Do think about the shape of your highlight. If you are working from a photo it might be round from the flash, so making it a different shape to follow the sphere may look more natural. The iris is usually not one colour and because it is a ball will have a lighter and darker side, so lift colour or when it is damp drop colour in at the edge to get the flecks and veins. While it is wet anchor it into the head, by using clean water around and encouraging paint to flow out. A narrow band of dry paper will give an edge to the eye and stop it going into a blob, but bridge it in places to stop it being too ‘cut out’.
Stage two, after it has dried (work on another part of the painting until it is dry), pop the pupil in and any shadow under the brow. The pupil will not be equally defined all round, it may flow into the iris in the shadow area. Keep your highlight, though if you lose it you can pop it back in at the end with gouache. Finally there is often a shadow in the highlight, where the pupil shows through, so you can put that in and continue working out from the eye. Let your brush follow the way feathers or fur grows from the eye and it will look more natural. You can see I have stared to work down to the beak here and add the eye brow feathers.
Eyes will help transform your paintings, so it is worth really studying them. Have fun and please be impressed that I resisted the temptation to make some dreadful pun like ‘the eyes have it’!