Salut members of this awesome community. I’m in panic for I have encountered a very pesky issue during one of my modeling practices. The issue in question is about understanding the mechanism behind a camera’s shutter diaphragm. I’ll proceed with the details.
First the references I’m using in this study. This is a shutter diaphragm:
And this is how it opens and finally closes (view from inside the camera):
My current model needs of 8 blades as the opening it creates is an octagon instead of a perfect circle unless it is full opened. I cannot seem to grasp how to model and prepare this for animation as I don’t know how this “contraption” works from within (as for the pieces which makes the blades to close and open and overlapping. I hope someone with more knowledge onto the subject can help me here to understand the mechanism of this since I lack the resources (or a real camera per se to butcher and see how it works inside).
There is also a small issue about the blades. I’ll show the current shape of my blades in closed stance:
I know, it is not a very pretty sight. The thing is that I used a reference about the shape of the individual blades (which I don’t know if they are arbitrary or follow a certain function depending of the camera):
((looks like I cannot add the reference here due to odd issues with posting the topic but you can see a tiny review of it on the last image on the right view panel))
I used the bottom left-most one as reference, but as seen in my screenshot, it seems it is not the correct shape to fill the gap with just 8 blades. Obviously if I open the blades to display the lens behind, the blades on their current position (and without modificating their semi-circular shape) end sticking outside the rims of the model. If I modify the shape of the blades so when they close they fill all the gap, whenever I open them they’ll gonna pop out the model (at least from the point of view about how I understand the diaphragm mechanism works).
It is very possible that I’m not getting right how a real diaphragm of these opens and closes, since whenever I try to imitate that motion, the blades end sticking outside the camera itself! Obviously I have seen plenty of cameras in my life… from the outside like any other regular mortal, but I never comprehended how the blades open so flawlessly inside those tiny cylinders without sticking outside like my current blades does.
I feel silly since the method I used is a regular pivot to the base of the blade and then rotated on the X axis until closing the gap and I’m starting to believe this is not the correct nor the proper behavior for a shutter.
Any help about understanding this might even help more people than me, since modeling cameras for later animation is one of the most recurrent subjects in 3D, but I failed to find a good tutorial/reference about this topic, hence my small message in a bottle comprised in this message. Hope you understand my question and hope you can help me to identify the problem behind how to make the shutter to work like a real life camera’s.
~ Mero
