Need some help positioning a Poser camera



  • @eclark1849 said in Need some help positioning a Poser camera:

    ... The AUX camera can scale but the dolly camera apparently can't. Is there a way to get the AUX camera to spin on it's own Y axis instead of the scene axis?

    Sorry but I do not understand: If you do not want to make weird effects, why do you need to scale your camera? You can set location, direction and focal length and for a normal camera that is pretty much what you need to get any perspective you want.



  • @F_Verbaas Changing the focal length or distance will distort the surroundings which I don't want. But i need and want to get as much of the room, which is what I'm showing off, into the scene as possible. I can only move the camera back so far, unless it's a smaller camera.


  • Poser Ambassadors

    English is now failing us.

    Scaling the camera doesn't help you see more with less distortion. What you see is entirely defined by camera position and the focal length. Focal length entirely determines the angular field of view. What you actually can see in the render is then determined by the FoV and your position.

    When you scale the camera, you're not at all changing the FoV but you are changing the position.

    So - based on what your stated goal is, I now pronounce your question moot. You do not need to scale the camera at all since it won't modify the situation in any way to solve your problem, which is that a wide FoV produces visible stretching of things near the edges of the frame.


  • Poser Ambassadors

    Note also that the physical dimensions of the camera prop shown in the scene viewer are not real.

    The camera is a point, located at the front lens center of that prop. The back of the camera can be outside the room and this does not affect what you see from the view point.



  • It is a common problem in 'indoors' scenes in rooms with life-size dimensions. You move the camera back to see more and then when you render you see the camera has wandered outside the room and the image is just showing the (backside of) the wall.
    My solution is to use a room with walls parallel to x- nd z- axis, use the dolly cam and set limits on x- and z- position to a range just some 10 cm or so inside the walls. Then I can 'walk' around with the camera as I want but cannot move the camera outside the room.
    What I did not try yet, but could work now that I think of it is use the 'hither' and 'yonder' settings.



  • @bagginsbill said in Need some help positioning a Poser camera:

    English is now failing us.

    Scaling the camera doesn't help you see more with less distortion. What you see is entirely defined by camera position and the focal length. Focal length entirely determines the angular field of view. What you actually can see in the render is then determined by the FoV and your position.

    When you scale the camera, you're not at all changing the FoV but you are changing the position.

    So - based on what your stated goal is, I now pronounce your question moot. You do not need to scale the camera at all since it won't modify the situation in any way to solve your problem, which is that a wide FoV produces visible stretching of things near the edges of the frame.

    What does scaling do then?



  • Okay, I just checked the manual and according to that, the camera scaling acts like a lens zoom control. So if I'm in a small room and I'm as far as I can go without the camera lens backing out of the room and through tthe wall. Scaling it will allow me to get as uch of the room as possible before that happens without the effect of the room disappearing into a single point in infinity.



  • Thanks for the help anyway, guys, but I found a way to get everything working the way I want.



  • @eclark1849 said in Need some help positioning a Poser camera:

    Thanks for the help anyway, guys, but I found a way to get everything working the way I want.

    Would you mind sharing to help those of us that might be having a similar issue?



  • @mr_phoenyxx First, i should mention, in case you didn't know, that when you create a camera in Poser it has two major drawbacks. One is that you can't really see the damn things to position them well, and the other is that they don't scale. Aside from that, when the user creates a camera it is either a camera that Dollies back and forth, side to side and turns on its own y axis, or it creates a revolving Auxiliary camera that revolves around the center of the scene. Neither of the user cameras have scaling dials.

    What I really needed was a Dolly camera that scaled. The dolly camera that originally comes with a poser scene CAN be scaled. It's the user created cameras that can't. By creating a primitive and parenting the camera to it, I can now scale the primitive and the camera will follow.

    Scaling a camera, according to the manual, has the effect of zooming a camera in or out of a scene without causing any distortion in perspectivie viewing. Which is what I wanted and needed.


  • Poser Ambassadors

    Except the manual is completely wrong.

    The word "zoom" means to vary the focal length. (Look it up)

    A zoom lens is one that has a variable focal length, versus a fixed or "prime" lens.

    Furthermore, the scale parameter is altering the coordinate system associated with the camera's rendering of the scene. You're basically changing the size of the universe, which, because you're positioned in it at a fixed xyz, causes your camera to move towards or away from the origin but stay on the same vector. It does not change focal length nor field of view in any way.

    You asked what it's for - it's there because of numerous effects having to do with parenting a camera to a head or eyeball or other weird scenarios, where the parented object has a scale and you want to compensate for that by scaling in the opposite direction.

    I don't know how to make a video to show what I'm talking about but I can show this in an animation when continuously manipulating the scale. The scale parameter basically is moving your camera (because it is scaling the world around it.) Uniform scaling does not change relative angles, ever. This is simple geometry.

    Try this.

    Set up a dolly cam opposite Andy's head in a standard zero position (Andy standing at origin.)

    Select the dolly cam and make it always point-at Andy's head.

    Now spin the scale dial. Hopefully with the point-at business, you'll see how the camera is moving towards or away from Andy's feet. Scale one way and the camera will look up at his crotch from the origin. Scale the other way and the camera will look down from high above. In all cases, your camera position will be along the vector from origin to the original XYZ you had the camera positioned to.

    Scaling is also part of a useful trick that gives that "camera breathing" effect where you move away and simultaneously zoom in with increasing focal length, or vice versa. This is done on some Poser cameras with the Perspective dial, which simultaneously moves the scale and the focal length. It makes a figure at the origin appear to stay the same while the whole world (and your view of it) grows or shrinks.

    Summary: What you can fit into your field of view is controlled by your camera position and your focal length.

    Any apparent control via "scale" is due to the fact that, unbeknownst to you, you're changing your camera position.

    Earlier today I actually wrote a program to change camera scale as well as dolly xyz coordinates so that even though scale is changing, the camera does not appear to be moving AT ALL. This demonstrates that it's all about final angles which is controlled by position and FoV. I cannot demo this, though, because I don't have good tools for screen grab animations.


  • Poser Ambassadors

    Here's another easy demo.

    Place your dolly camera at DollyX = 0, DollyY=0, DollyZ=0. Move some other objects or figures so you can see them from that position at the world origin.

    Now - spin your Dolly camera Scale dial. Absolutely nothing happens. This is because you're scaling the xyz position, but it is 0,0,0 which means no matter how you scale it, position is still 0,0,0.


  • Poser Ambassadors

    Here's my preview with dolly camera at 0,0,0. It looks exactly this way at any camera scale.

    0_1463162058381_dolly at any scale.png

    Andy was moved back 30 inches so I could see him from this spot.



  • e, what are the dimensions of the room?

    The only options that I'd ever touch on the camera are Focal Length, XYZ axis, Roll/Pitch/Yaw and FD for DOF. If you're looking to get a small room in your FoV you're going to have to use a wide angle lens/number of 25 or less. That might bring a lot of barrel distortion depending on how close the figure is to your camera but that's easily correctable in post.



  • @johndoe641 Or i can scale down the camera and move it back. I don't know if it fits what BB says, but it works for me and that's what i was looking for.



  • @eclark1849 Wouldn't it be easier, just to turn off the visibility on the wall, object, that's blocking your view (so you can position the camera to the position that you want) go to the parameters tab (with the wall,object selected that's blocking your view) click off the visible in camera, leave the visible in raytracing left on. Scene will render minus the blocking wall, object. Caveat is that you need to tun off all parts of the wall, window frames etc. And you need to frame the camera view within the room, works for me when trying to get renders in tight room scenes.



  • If you are using Superfly really your tool of choice for making shoots in a small room should be the 'hither' dial. It works just like the focal distance (not the focal length, that is something different).
    It simply makes everything that is less than the distance you set it to from the lens invisible. The dial by default is set to a small value, but if you dial up the value to match a position between the obstructing walls and your figure you will see the obstacles do not show up in your render.
    BTW For me this worked only in SuperFly. In PoserPro11 the function seems broken in FireFly.
    See below result of Andy2 in a default Poser cylinder sized up to 1000%. I set Hither to a value that just cuts the cylinder to show the effect. Note how the lower part of the image, the ground (the construct) is cut away and the Poser background is shown.
    0_1463245632013_AndyInCylinder.jpg

    Note the similar dial 'yon' ('yonder') can be helpful to make renders witth the figure without the background while using the Poser11 Construct.



  • Just adding that in the above I made the cylinder somewhat transparent so there is light on Andy. If the walls are not transparent you need to provide light sources, If there is no light in the room, there is darkness and that is what Superfly shows.
    0_1463247591216_AndyInCylinder-Superfly_0001.jpg
    This is Andy in complete darkness in the cylinder without transparency. The light stripes at the side are parts of the outer wall.
    Note the geometry less than the distance set in 'hither' is not removed form the scene. This is Superfly and if the geomettry was not there Andy if not in direct light would have ben lit by diffuse light from the Construct.
    0_1463247653547_AndyInCylinder-Superfly_0002_0001.jpg
    Here I added a point light in is dark dungeon.
    Of course for real room shots you would zoom in to ensure you see only the room.



  • @dgould2001 said in Need some help positioning a Poser camera:

    @eclark1849 Wouldn't it be easier, just to turn off the visibility on the wall, object, that's blocking your view (so you can position the camera to the position that you want) go to the parameters tab (with the wall,object selected that's blocking your view) click off the visible in camera, leave the visible in raytracing left on. Scene will render minus the blocking wall, object. Caveat is that you need to tun off all parts of the wall, window frames etc. And you need to frame the camera view within the room, works for me when trying to get renders in tight room scenes.

    I don't see doing all of that as being "easier" than simply scaling down the camera and moving it where I want it, but if you don't mind going through the extra steps, yes, it's a viable option.

    Of course, since I am the one making this room, I was also looking for a way to include a camera pre-set so that I wouldn't need to include a hundred different mat zones to make walls disappear.

    @F_Verbaas said in Need some help positioning a Poser camera:

    If you are using Superfly really your tool of choice for making shoots in a small room should be the 'hither' dial. It works just like the focal distance (not the focal length, that is something different).
    It simply makes everything that is less than the distance you set it to from the lens invisible. The dial by default is set to a small value, but if you dial up the value to match a position between the obstructing walls and your figure you will see the obstacles do not show up in your render.
    BTW For me this worked only in SuperFly. In PoserPro11 the function seems broken in FireFly.

    I'm not using Superfly, as I don't have PP11 yet. However, even if I did, I'm not trying to support ONLY Superfly. Still, I'll keep your suggestion in mind if I do something similar in the future when I DO have PP11... or 12.:smiley: