Hey Paul,
Let’s do a quick elaboration on the model you have. As long as the mirror axis is spot on the world axis (it can be on the object axis as well, but for the exploration now, lets go that route), which means that the values of one side of the axis will be negative, the other side has positive values. This is since the 17th century based on RenĂ© Descartes a standard (Cartesian coordinate system), so I think we agree on that point. (World uses the default axis, Object the axis of teh model, in both cases teh axis origin is set where the “mouse” finds a reference point)
Back to CINEMA 4D, if you have mirrored the half fork around the world axis, the resulting points on the other side must have the same value, except if the were positive, they are now negative, if they had to cross the mirror axis. (Or vice versa) This is not a given in Object mode, if the object is far away from the world axis, hence the exploration in world, to prove the point. If in model mode, you can later move the result to line up with the world axis and get the same precision. Just to clear that “point”.
Go in Point-Mode, and with the fork-spline selected, switch from the Object Manager to the Structure Manager. If you click on any point of the fork, you will see that the values of the points have one highlighted line. Memorize the point number (the first in the line. Now click in the editor view on the point that was mirrored. A new line in the Structure Manger will be highlighted. Compare now the numbers for X,Y and Z. (If there are no lines, inside of the Structure Manager, go to the menu “Mode”, and set the entry of that menu to Points.) You can of course select two symmetrical points at once, if the screen is large enough, and it should be for the fork, the lines will be shown—as in my image. Points following the axis “up and down” will stay negative or positive, so typically one point changes the polarity only—but the values (absolute) will be the same.
CINEMA 4D works in floating point values, with (to my knowledge) double precision, since some years as standard. When I got my first version of C4D in 1996, I could chose which precision to install, as computer time was valuable. If I’m not mislead, this option was only given around that time. Today, we have for Computer Graphics certainly a precision that is not really a problem—at least not visually.
As I mentioned earlier, the image was the problem, as practical photography has not that precision as C4D has. I speak from 35 years photography with a strong emphasis on reproduction photography. But I think no-one would argue that aligning an object with a camera or even putting it on a scanner might have some tolerances in the alignment. One could argue that the photographer could have rotated the image to have a great results. But if details are the key, then every starter in Photoshop will know, that moving pixels by pixel-increments will lower the image quality by at least a quarter. Same is BTW true for lens correction methods, moving a pixel by a none full amount, renders the new value as an average with the neighbor pixels. Simple math, nothing to argue here I hope. Working in Ps since 1993 I think I have seen all tools and cheap tricks, some beginner might have the idea to fix it with sharpening or similar horrible tools (speaking of reproduction photography), I hope we can take the point home, that we don’t do this in reproduction work.
So, even if the image was not perfect as a C4D render, why would use Patrick such imperfection in the first place? We talk about tutorials here. To take a “perfect” image and model from there, would not have caused Patrick to talk about alignment problems. Tutorials are there to get the procedure clear, and while doing so, introduce the tools necessary. A good tutorial shows these kind of problems that one can have. Bad tutorials run just as fast as possible to the result and doesn’t case what kind of problems could have possibly shown up by doing the next similar—but different—project. It shows Patrick’s experience having modeled tons of objects, to point that out. Again, a tutorial done by a beginner would not even have bothered to go that path. Patrick’s work is clear, structured and well thought out. I don’t see a problem with the tutorial in question.
I like to work on road-blocks with people here inside their use of 3D. I can’t see a problem related to the use of C4D or any problem that has to do with 3D. With that, I can’t go further, having been a mentor since many years from time to time, I know my borders and my place.
For the Polygon/N-Gon problem, please use a new thread.
My best wishes.
Sassi