The eyeball conundrum! [question]

# 1 19-03-2004 , 03:53 PM

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I need some advice.

I am working on a head model and I am running into a problem that seems to have a recurrent theme.

The eyeball / eyelid interface does not match from the front vs. the side view. I have seen this both for drawn images and even photo images.

The side view of the eyelid/eyeball interface always seems larger then it does from the front view. Can one of the artistic gurus among you ...

(a) please explain why this front / side disparity exists?

(b) in modeling what is the correct solution:
1. model the front?
2. model the side?
3. model somewhere in between?
4. go to the bar and get drunk? :wink:

Thanks,
Rick M

see 2 attached images:

(1) Front view - green curve outlines eyeball/eyelid interface

(2) Side view - green curve outlines rough guesstimate of the eyeball/eyelid interface

I am sure some of this is the result of the stylized drawing but I have seen this effect even when I have taken digital images of a subject.

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# 2 19-03-2004 , 05:18 PM

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to be honest with I think the image planes are off.

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# 3 19-03-2004 , 09:59 PM

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they are off... if you look at the grid, you can tell the side image plane is lower than the front.

There can not be Good without Evil, so then it must be good to be Evil sometimes.

:tup:

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# 4 19-03-2004 , 10:31 PM

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em... the planes are off by like .1mm and that does not explain why one eye outline would be 2 times the size of another??

LOL

They are not even off by .1 mm actually.

There is exactly 5mm from the top gridline to the top of the eyeball sphere and 6mm from the bottom gridline to the bottom of the sphere in BOTH front and side views. In any event the image planes alignment are clearly not to blame for this anomaly.

The scale of the eyes as drawn possibly but that does not explain why I see this same effect from digital reference images.

There is some trick of perspective going on. I have seen this exact same thing with digital pictures taken from exactly the same distance and angle.

I am sure anyone that has modeled a lot of heads would be familiar with this and might care to share what the cause and solution is?

Mike or Kevin or Kurt any of you guys seen this kind of thing before?

"If I have seen further it is by standing on the shoulders of giants." Sir Isaac Newton, 1675

Last edited by ctbram; 19-03-2004 at 10:39 PM.

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# 5 20-03-2004 , 01:17 AM

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Okay it looks like these image planes are just drawn poorly and the size of the eye do not match. I looked at the final model from the book and it is clear that they just fudged an eye somewhere between what is drawn on the 2 image planes.

I have to freaking LOVE people that make tutorials for people with NO modeling experience then give them reference images that do not match! I am sorry but this is really a sore point with me.

I know in the REAL world you don't get matched front and side reference images but when I write a tutorial for complete noobs to give them drawings that DON'T MATCH then SAY USE THESE DRAWINGS TO BUILD YOUR 3D MODEL OVER is just stupid!

Once again I sit here and push and pull cv's for hours trying to match a single model to a pair of views the DON'T MATCH. Then after a day and half of trying to figure what the HELL I am doing wrong I find I could never match the model to the reference so I must ask - What is the point of the references?

You may as well give me a picture of a duck in one view and a frog in the other and then tell me to model a cow!

"If I have seen further it is by standing on the shoulders of giants." Sir Isaac Newton, 1675

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# 6 21-03-2004 , 03:09 AM

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Could you possibly provide a link with this file so that people can try and reproduce the issue?

And what book if you don't mind me asking....

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# 7 21-03-2004 , 10:05 AM

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Sure, I will put the reference images on my web site. Might take a day or two. I am going to bed now and will be out all day tomorrow.

The book is "Mastering Maya 3" by Kundert Gibbs and Peter Lee.

"If I have seen further it is by standing on the shoulders of giants." Sir Isaac Newton, 1675

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# 8 21-03-2004 , 04:13 PM

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Go here for the source images:

https://home.comcast.net/~rmulawa/may...urceimages.rar

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# 9 28-03-2004 , 03:01 AM

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My apologies for not answering...got some things that need my attention more atm. When I get back home this week I will look at it....again sorry for taking so long....

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# 10 03-04-2004 , 02:54 AM

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I spent 20mins trying to get my planes to work.....it seems I have more issues than this.....

The only thing I can think of is that your pics are not the same size....therefore your ratios will be off....

face_front = 528x699
face_side = 571x698

And if the author did this and it worked for him/her...then they should explain what they did.....nothing frustrates me more than when tutorials are done and there is one small thing that the artist does to get the result, and he/she does not tell us about it.

Sorry I couldn't be of more help......

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The eyeball conundrum! [question]

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