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Working on this view where the full render actually goes quite a ways beyond the top. I need to add a fixture mounting plate at the ceiling which I had somehow deleted before the final render, and want to just do a small (i.e. quick) render of that part and then Photoshop that in my final, completed image. The problem is that it's way off the screen. I'm assuming that if I zoom back that it would not match the perspective view of the original. Any ideas?

you could open the mxs in studio, there you can fully see the lens shift.. or calculate the shift needed upon your already rendered image. guess a few test would get it right

How is your camera set up -- how are you specifying the output dimensions? What does the viewport look like if you enable the camera HUD?

If you have set the output explicitly, Camera > Output Resolution > Presets should read Manual. If that's the case, then you are able to change the size and shape of the viewport independently from the rendered output. With that in mind, you could make the physical viewport very narrow and tall without affecting the perspective of the shot, and then use the plugin's Pick Film Size Rectangle command (in the Camera toolbar) to render the area you want to. Keep in mind that this uses the shift lens to accomplish its job, so the most it can offset is 100% along each film dimension.

There is some discussion about this here: http://www.maxwellrender.com/forum/view ... 23#p269523

polynurb wrote:you could open the mxs in studio, there you can fully see the lens shift.. or calculate the shift needed upon your already rendered image. guess a few test would get it right

This was an easy way to do it. Thx for the help. (JD: I tried what you suggested in Rhino but it's so far out of the view that the area to be rendered would have been quite tall and hence require more render time). Joe

Josephus Holt wrote:

polynurb wrote: the area to be rendered would have been quite tall and hence require more render time

i think that is not quite true, it works the exact same way in rhino and studio... the only difference is that a rhino viewport will always show 24mm film (scales your vertical resolution defined in MX camera 1:1 with vertical pixels in viewport) .... no way to change that.

this means you won't see where you are shifting to.. but technically there is nothing wrong with shifting out of the viewport .. and it is quite easy to calculate.. lets say i render 800x400.. 50% Y shift mean 200 pixels.. so you can look up where on the render you part is, and shift accordingly

polynurb wrote:this means you won't see where you are shifting to.. but technically there is nothing wrong with shifting out of the viewport .. and it is quite easy to calculate.. lets say i render 800x400.. 50% Y shift mean 200 pixels.. so you can look up where on the render you part is, and shift accordingly

You will see it if you enable the heads-up-display, switch the camera to Manual resolution mode, and then stretch the Rhino viewport around so that it's extremely wide/short or narrow/tall. Playing with Pick Film Size Rectangle at that point will let you render up to a full frame height or width from any edge of the current frame while still keeping a correct resolution and perspective match.

why did i think this trick would only work on the horizontal axis... i don't know.. thanks for correcting me!

Not so much correcting you , but just putting the information out there -- it is not exactly obvious, because Rhino's 24mm film 'height' applies to the viewport width when the viewport gets tall/narrow. So, conceptually, Rhino 'turns the camera on its side.' If you leave a Maxwell camera set to Viewport resolution mode, you'll see this fact reflected in the camera's film size as you change the viewport shape.

JDHill wrote: So, conceptually, Rhino 'turns the camera on its side.'

now i get it... and see it.. but i really wasn't aware of .. because you have to scale it below a 1:1 ratio.. and i thought.. it will always keep on scaling the horizontal FOV only.

say.. at this point.. can you elaborate a little about what is going on when i render a 2 point perspective view in rhino5 wip?

.. i got a nice view set up like that.. and it took me a while to reproduce it as seen in viewport, because the filmback rendered much larger than what was shown in OpenGL.

just wondering how it relates to maxwell .. because the 2 point view was a huge lens shift itself .. which wasn't possible in rhino alone until now.

The Rhino V5 WIP two point perspective view is not factored in at all, since Rhino 4 is still the only official target for the plugin. So, I couldn't really say what you should expect if you try to use that feature right now. It was mostly Rhino's lack of this perspective mode that necessitated the camera HUD in the first place...so I have no idea at the moment how the two things will be made to work together, if at all. I would really have preferred they implemented a more robust film model before going into things like this...until that happens, the experience is always going to be sub-optimal, imho.