Thank you, and not to bump this ancient thread, but I've just noticed a post by Dave/Optikanet at The Anorak Zone, from way back. I want to comment on this, because it seems you didn't understand what I was trying to say about the mismatched eyes. I think it's an extremely important rule for artists to learn.
Rotate your images so that the eyes are level, before you start drawing. This doesn't mean altering the original image in any way or "fixing" lopsided eyes. [Patrick Troughton's eyes actually are a bit lopsided in real life - his whole face is lopsided, but drawing him with his eyes level will successfully capture that rather than eliminate it].
Any drawing you create is an imperfect copy of the original thing. Any artist is throwing away huge amounts of detail and inventing his own. What you're doing is, in your own brain, drawing what seems correct to you.
Try flipping any drawn image horizontally and it will be a shock how different it looks. Because the character has gone through that weird filter that is your brain.
It's equally true that if you were to draw a character rotated 45 or 90 or 180 degrees, you could draw a character that looked fine to you from that angle, but when you rotated that character back to normalcy, the character would look bizarre. Because it's been through your mind's filter, and no artist is perfect enough to avoid that.
What will always seem most correct to an artist is symmetrical eyes, so any eyes you draw will have a symmetrical quality to it. if your actual image doesn't have the eyes lined up on a straight line, you will draw them wrong and lopsided. You can't help this.
If you're drawing something as simple as Cosgrove Hall's work, you can sometimes get away with an angled face, because your brain has the capacity to draw simple geometric shapes correctly. Sometimes.
But it's usually not worth the risk. Any artist is learning to draw these characters right, so take the 2 seconds to rotate the eyes to be a straight ____________ line. There's no reason not to.
Here's what Dave/OptikaNET posted.
Okay, this is the kind of thing I need advice/feedback on:
Most people hold their head at some kind of angle, rather than strictly horizontal. Photography books warn amateurs to ensure that their horizon is strictly level because what seems level to their "eyes" will look weirdly tilted on the photograph if their head wasn't level at the time.
Knowing this, it's obvious to me in the Troughton above that he's holding his head slightly down to the right side (our left) which therefore elevates his left eye.
Now, it's being suggested to me on Who3D that his left eye is higher than his right (which is strictly true, but accurate to the source) and that I should adjust it accordingly because it looks "wrong".
Here's the conundrum - I understand what they are saying, and I understand to the non-artist this may be troubling to look at, but if I "correct" it then I won't be true to Troughton's character and in a piece of moving footage, this could look subconsciously "wrong" as well (in much the same way as symmetrical faces - eg if you mirror one side of someone's face in Photoshop - look unnerving because faces are always asymmetrical even though most people don't realise that on a conscious level.
So I appreciate the poster's feedback and advice, I understand what they are saying and they are not incorrect, but I'm unsure whether to agree or disagree with them because either way I could be said to be "wrong"

Sometimes the best thing to do is the "wrong thing" because it looks more right than the right thing does!!! (For example, photographers again; if a portrait shot is ordered by family and friends then it can be printed as normal without problems, but if it is commissioned by the portrait-sitter themselves it can be best to print the photo reversed left to right because this is how the recipient sees themselves in the mirror and it's what they think they look like, so they'll be happier with the finished product (although family and friends will not like it).
Personally I think that the brain will accept stuff like this in a moving image far better than it will accept a still image, so I should leave well alone, but I've asked for advice, I don't want to ignore it without reason, and I'd like to know what the forum thinks.
Kind Regards
Dave