Catch lights in the eyes...
 

When you paint those little catch lights in the eyes, placing them a little higher than they actually are will oftentimes make the person look "more alert."

Below is an example of this. I "doctored" the Mona Lisa's eyes (with profound apologies to Leonardo). On the left the catch lights are lower than they are on the right.

It is a subtle difference, but I hope you can see that the example on the right makes her look more "alert."

Would I be lazy to ask which was Leos' way?

I enjoyed a Sargent at the Phoenix art museum in which the catch lights are actually above the lid, near the brow really. I love that it works from 20 feet. I know that Sarg painted (or decided from 20 feet) and probably simply put it where he saw but it's cool and brave! and the work pulses with life, which a nice effect in a painting I think.

Ok, Tim, I'll bite..
 

Which Sargent was that? I want to see it! I spent September in New York drooling over the collections but have totally forgotten where he is hiding in PHX!

It's a small head and shoulders, very late and very nice...a businessman. It's small yes, but amid the really famous people (the portrait room) it rules! Phoenix, like many museums, doesn't realize what the good stuff is and it may be in storage. You might want to call ahead. Enjoy!

The higher highlight is a good suggestion. I also found it necessary to make that highlight not as white as I often made them when closer to the center of the eye.

On some ocassions I have had subjects with deep set eyes and did not find (nor paint) highlights. (See the attached study). Also see the Sorolla self portrait under "Artists of the past/Sorolla" thread. The effect makes the subject look intense.

Suitablility to the subject.
 

Because I am not in the ranks of official portraitdom, I am still perhaps too tied into the quality of the picture. When the model is not investing in the outcome there is a lot more freedom. I think I have learned, as Karin is pointing out, the value and intent of that glint.
There are times when my model simply does not have one. I used to love flicking it in at the last of the picture to sort of wake up the model I had been working on for the past few hours. Now it is not a rule. I find myself considering how alert a subject may actually be.

Mona is dreamy. Looking out in anticipation was a bit of contradiction to the whole mood of the piece. Alert is an option. The value of this thread is to point out the variables in the intention of portrayal of the subject. I have many friends who ask me the "right" thing to do in a painting... Tips and information are all good, but I appreciate more this sort of thing, as an input as to how to make decisions, not which decision is the correct one.

Jim's young gentleman and his introverted expression would have looked angry with that much intensity and alerness too.

A good choice for a specific intention. Thanks for making me think.

Jim, That's a great head! well done

I find it useful to think about how it is that that catchlight is there in the first place, which permits me to manipulate it to my own purposes and, as importantly, avoid doing so improperly. As with any highlight, it appears where there is a surface turning away from or toward the light. In this case, it

Who would have thought that "catch lights in the eyes" could spur so much comment?

With apologies for using my own work to illustrate a point and for the poor color and quality of print (Done quickly on current painting in the works and with all those darn canvas highlights reflecting back). Steven's sage advice and the immediacy of this wet canvas was opportune.

In this portrait (detail) the white of the eye is lighter than the highlights and I think I will keep it that way although I always (almost) tell students to avoid making the "whites" of the eyes a white value. I guess you could say that I have three highlights (no extra charge). This now makes up for a painting that I made some time ago with a highlight in one eye only.

I agree that the sense of alertness is greater with a higher highlight...however, if that is what I was after, I would take pains to either light or place my subject so that that is the highlight that exists; I would not arbitrarily move one, though. I think the catchlight is very important in placement, shape and color, and should be rendered as just a "dash".

I generally use a convention (Harley Brown, tried and true) of shifting the color of the highlight to the opposite temperature of the light source...for incandescent lights, a very light blue or violet, or pink; for cool light, a warm white. I think, though, that it's best to paint it as you see it, and most importantly as you see it from your position AT THE EASEL.

While it is essential to paint the catchlights, if they appear in both eyes, in the same relative position, I find many times when they are not of equal value, or when the color shifts a little.

I am also of the school that says if you do not see a catchlight, don't put one in.

Chris