[jeje]

hi there

does anyone know there is any possible reasons that causes my final rendering is out of focus? like the object in the middle of the rendering is blurred.(sorry, because of the technical reasons, i couldnt upload the rendering) Like, is that the camera is too close to the object?

my setting is
Fstop 8
shutter 125
sampling level 20
bounces 8
D65 500w & D65 300w for the emmiters

cheers!

[Frances]

What are your units? I've found that Rhinoll works best when the units are set to Meters. Maxwell's default units are meters and there is no mulitplier function yet in Rhinoll.

[znouza]

hi there

does anyone know there is any possible reasons that causes my final rendering is out of focus? like the object in the middle of the rendering is blurred.(sorry, because of the technical reasons, i couldnt upload the rendering) Like, is that the camera is too close to the object?

my setting is
Fstop 8
shutter 125
sampling level 20
bounces 8
D65 500w & D65 300w for the emmiters

cheers!

Press F6 or type 'showcamera' command to show up your camera. Or type 'placetarget' and place camera target to your object you want to be focused to.

[jeje]

What are your units? I've found that Rhinoll works best when the units are set to Meters. Maxwell's default units are meters and there is no mulitplier function yet in Rhinoll.

I use millimeter system, whats the leap it could make to use meters??
thanks Frances

[jeje]

Press F6 or type 'showcamera' command to show up your camera. Or type 'placetarget' and place camera target to your object you want to be focused to.

znouza

its great to know the tip, however it doesnt affect the final result

[znouza]

Press F6 or type 'showcamera' command to show up your camera. Or type 'placetarget' and place camera target to your object you want to be focused to.

znouza

its great to know the tip, however it doesnt affect the final result

send me your image to my mail - tomas@meinlschmidt.org ..

1. check camera focal length (right click on 'perspective' label and select 'viewport properties'. 50mm should be great
2. check camera target as I wrote above - if the camera target is out of your object, it will be blurred
3. check f-stop and shutter speed - higher fstop makes longer DOF (more sharp objects) - use eg. 1/60 and f/8
4. units in meters

[Frances]

With all due respect to Cedric, please just try changing your units to Meters via Rhino Properties (right-clik the blue render ball). When asked to rescale, do it. Zoom extents to see your model again. You will need to redo your Perspective view. As znouza suggested, try setting your lens length to 50 mm in Viewport Properties (right-clik the Perspective viewport label and click Viewport Properties).

[Thomas An.]

With all due respect to all here.

Units have absolutely nothing to do with it and Maxwell / Rhinoll is correct.
Since we are dealing with a physical camera the scale of the model is important.

In this test the distance between the posts is constant (at 1meter) but the units are different while all other parameters are the same. True enough the result (as expected) is identical.

So units are completely irrelevant as long the scale is right. (you can work in micron or centimeters... doesn't matter, but keep in mind the scale)

The orange arrow indicates the camera target

[tom]

thank you thomas very accurate!

[jeje]

thanks a lot to thomas, frances, cedric and znouza

I had a second test with a fstop set at 32, shutter speed at 15, and focal lengh at 35, now the image turns out significantly improved sharpness and focus!
thomas, your diagram helps a lot!!

thanks all again

[Frances]

Thanks Thomas. So what you are saying is that Maxwell has no notion of units, but only of relative scale?

What lens length did you use for your tests?

[Thomas An.]

Maxwell is using a real camera which means, it needs to know the dimensions of the model relative to the camera.

Thanks Thomas. So what you are saying is that Maxwell has no notion of units, but only of relative scale?

Well scale implies units but we do not need to worry about what kind of units because Maxwell is doing the conversions behind the scenes. So basically Maxwell knows that 1million microns are actually one meter.

If you want to take a picture of something small then you need to shrink the camera too along with your model.

What lens length did you use for your tests?

The previous test was with a standard 50mm lens

So to continue from the above example, if we shrink the above model so the distance instead of 1meter is now only 1cm (100x reduction) then we need to shrink the camera 100x in order to get the same result. To shrink the camera it means to adjust both the film size and the lens length

In this test the camera was shrunk 100x. Film width=0.36, film height=0.24, lens length=0.5mm. True enough the image is identical.
(btw. at 0.5 mm the Rhino viewport looks garbled, but the maxwell camera sees it correctly)


As a side note: At the bottom of this page there is DOF calculator for real cameras.

[iker]

Yes Thomas you are completly right, converting cms,mms or small units to meters "without" scaling is just a quick solution to get no DOF because you increase the distance between the Near Focus limit and the Far Focus limit, but not the correct way to use a camera.

Great tests!

[Frances]

Well scale implies units but we do not need to worry about what kind of units because Maxwell is doing the conversions behind the scenes. So basically Maxwell knows that 1million microns are actually one meter.

So what is the point of the multiplier in the Max interface if Maxwell already knows? It led me to believe that Maxwell requires that number to be correct in order to determine the units of the scene.

Also, I think Rhino's camera goes whacky after too much panning and zooming and the target gets in a weird place. That might explain why changing the units fixed my situation - zooming to extents resets the camera.

[Thomas An.]

So what is the point of the multiplier in the Max interface if Maxwell already knows?

Possibly to avoid having to scale the camera up and down.
(Right now Rhinoll is using 1:1 ratio Rhino/Maxwell units)