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I am modeling a head using a reference image and have realized that the silhouette of the character in perspective is completely different from the silhouette of the character's front orthographic view which matches my reference. This almost seems to make my reference image useless since my model will never look the way I intended it to from the front. My project won't allow for rendering in orthographic, but I wonder how I can make my character look like the reference image if I have my perspective camera at a similar angle. (Do I have to just ditch the reference completely?)

My model the shape I want it to look at a close front angle (Which matches my reference perfectly

My model the shape my perspective camera renders it at a similar angle.

Why is it suddenly so thin, I specifically want the head wider but if I make it so, I wont be able to use my front and side shots whatsoever since they don't match the perspective camera. Is there like a magic focal length I can use?

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    $\begingroup$ try to use a focal length close to the one used in your reference image? $\endgroup$
    – moonboots
    Jun 17, 2021 at 7:19
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    $\begingroup$ @moonboots If the focal length is known, this would be best. But then it still depends on looking from the same distance to the object as the camera's distance to the face. Maybe if you're working on something in viewport you change the viewing distances. $\endgroup$ Jun 17, 2021 at 7:27
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    $\begingroup$ Yes I guess there's no perfect solution, you need to correct the shape using your own instinct $\endgroup$
    – moonboots
    Jun 17, 2021 at 7:30
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    $\begingroup$ To match model with reference image you have to replicate real camera setup with Camera object setup. It can be taken from image meta data (partly) or try to reconstruct from perspective (it there is any) with fSpy app. The best is to take those parametrs from real camera when you shoot images. $\endgroup$
    – vklidu
    Jun 17, 2021 at 8:27
  • $\begingroup$ In principle, it should be possible to lock each vertex's position to a line going from the camera to that vertex, right? But I doubt this actually would be useful. $\endgroup$ Jun 17, 2021 at 8:40

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No, there is no "magical focal length". And although it might look strange that's how perspective works... it distorts objects in 3d space perspectively.

However - and that's how you can do it with a real life camera for example - to minimize the perspective distortion you just have to go further away from the object and use a higher focal length. For the camera view you can change that in the camera's settings, but if you want it while you're navigating freely in the 3D Viewport set to User Perspective, you can change the Focal Length for the viewport in the sidebar settings (bring the sidebar up with N if it's not displayed).

The default setting is 50 mm, but you can try with 150 mm or 200 mm. This makes the view zoom in on the objects, which lets you view them from further away and thus results in less perspective distortion.

EDIT: Like @moonboots said in the comments, it might really help if you knew the focal length of the reference images, though the distortion still depends on the distance to the object. Typical focal lengths for portrait photography are between 70 mm and 200 mm, the most popular (if one can generally say so) are 85 mm as well as 100 mm, 105 mm and 135 mm.

focal length 3d viewport

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    $\begingroup$ Why do you navigate OP to setup 3D view. I would say you correctly spotted "Camera distance" has to match (not only Focal Lenght). So to match reference view through Camera object has to be set (also to be able use reference). By viewing out of camera you can't control view distance. $\endgroup$
    – vklidu
    Jun 17, 2021 at 8:23
  • $\begingroup$ I guess I misread the question, I thought he wanted to navigate in the 3D viewport with a perspective view while he's working on the character. In this case you cannot always keep the camera distance the same, because working on details might require zooming in on those parts. $\endgroup$ Jun 17, 2021 at 8:47
  • $\begingroup$ Thank you! This is exactly the kind of info I was looking for. I know that perspective is what it is and with other projects I just accepted it, but for this instance I want to stick to the reference until I'm done with it then compensate after. So changing the focal length temporarily while I model is what I'm going with for now. $\endgroup$
    – Zenoctra
    Jun 18, 2021 at 3:00
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I don't think you can model a photo that has a perspective quality in orthographic view. I mean, you can, but then you will have the result that you do. You should probably hit the key for orthographic front view (normally Numpad1) and then change the view to perspective (Numpad5) and model from that.

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