Camera Focal Length?


BeachHouse1
 Share

Recommended Posts

  On 5/25/2020 at 2:30 PM, BeachHouse1 said:

Is there a way to precisely set the focal length for cameras?  

Thanks?
 

Expand  

 

You would need to look at camera in plan view,  you can see the end of the focal length in plan view,  you can drag that tip back and forth,  so all you need to do is draw a line the length of the required focal length and snap the camera tip to that cad line......  

  • Like 1
  • Upvote 1
Link to comment
Share on other sites

  On 5/25/2020 at 8:40 PM, Kbird1 said:

 

FOV is the width of the angular view in degree , not the length to the focal point Dz.

 

M.

Expand  

Correct, but that's essentially what you are changing when you change focal length.  They are inversely proportional.  

Link to comment
Share on other sites

 

  On 5/25/2020 at 2:30 PM, BeachHouse1 said:

Is there a way to precisely set the focal length for cameras?

Expand  

 

This is interesting !!  :)

The OP asked about setting focal length and you guys are all talking about the focal point.
The distance from the focal point to the camera does not equal focal length.
All the focal point does is aim the camera and set the distance the pivot point about which it rotates is from the camera.

IF there were an actual focal length setting in Chief, it would change the camera's field of view, and vice versa.  

Anywhooo... perhaps the OP was actually looking for focal point instead of focal length?   Joe?

Link to comment
Share on other sites

"The focal length of the lens is the distance between the lens and the image sensor [film in the old days] when the subject is in focus, usually stated in millimeters (e.g., 28 mm, 50 mm, or 100 mm). In the case of zoom lenses, both the minimum and maximum focal lengths are stated, for example 18–55 mm."

 

Like Mark says, the "focal length" changes the field of view - think telephoto vs. wide angle lens. 50mm is approx. what the eye naturally sees.

Link to comment
Share on other sites

  On 5/25/2020 at 2:48 PM, BeachHouse1 said:

Thank you Scott you are always very helpful.

Expand  

This is the OP's second post in reference to Scotts suggestion to draw a cad line to the correct length, so it would be safe to assume that he wanted the focal point distance from camera.

Chief refers to this line as the Line Of Sight.

Link to comment
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
 Share