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MJV
11-28-2004, 07:09 PM
Here is my first render with XSI. The geometry was imported from Cinema4D. Credit to JDex for answering my newbie questions which allowed me to get this far. The image uses final gathering and the HDRI background is stpeters_cross.hdr.

http://www.mvpny.com/VaseMV8.jpg

Some questions. First of all, I'm wondering why the visible seem in the background. It uses Cube Cross projection. Secondly, I'd like to know how I can sharpen up the vase texture without using an external app. In Cinema I have many interpolation choices but in XSI not so many. I tried activating the Elliptical Filtering option in the Image Filtering page. What does it do? Not only was there no visible difference in the final render whatsoever, but the render time went from about four minutes to 48 minutes. Whoa! That's a mighty big time difference for an identical result.

JDex
11-28-2004, 07:25 PM
The seam is likely just a flaw in the file... I sometimes find strange things like that on hdrs from the web...

The texture sharpening is something I think you have to go out of app for... unless you have XSI Advanced w/ the FX Tree...

As for elliptical filtering... the manual can fill you in further, but basically it is a "memory-in-use" reduction tool... when set properly it allows MR to change the resolution of your texture based upon the distance of the texture to the camera... thus you can make a 1024 texture, but when the object is far from the camera (and very small in the render... MR will resample and shrink the texture so that in memory it is only the size it needs to be to get a good result (like 128 or something). The increase in render times is supposed to be negligable or very small when the feature is set properly, but I haven't needed it enought to get in there and learn how to set it up...

Cheers and keep it up.

Eraq
11-28-2004, 08:21 PM
You can adjust some parameters on your texture. There are some very standard colorcorrections tools on the textureclip that might be handy and you can check out the different imagefilter available.
If you are lucky to XSI Advanced you can play around with the filters in FX-tree like Jdex says.
But in the end you might just want to use a image with a larger resolution to sharpen your texture.


Regarding the seam in your environmentmap I suggest you rotate the projection so that it wont be noticeable in your render...

Erik

MJV
11-28-2004, 08:55 PM
All the cross files I've tried have the same seam problem, and if I'm not mistaken, these are original hdr cross files I got from the HDR shop site.

MJV
11-28-2004, 08:56 PM
Regarding the seam in your environmentmap I suggest you rotate the projection so that it wont be noticeable in your render...

Erik
You're joking right?

ThE_JacO
11-28-2004, 09:02 PM
to modify the maps without moving to an external app you could move to the rendertree.
there's a fair deal of tools handling color inputs, all of them you can use them to process the image node output, start with the color correction node and see if it brings you anywhere.

re: eliptical filtering it has nothing to do with the crispness of the map, oversimplifying a bit (for the sake of explanations) it's a filtering process that helps a lot with high res textures that stretches all the way from foreground to distant backgrounds (the classic example would be a tiled checkerboard floor that goes from the cameraman's feet all the way to the horizon and produces an increasing amount moire distortion effects when the distance from camera increases).

about the seam I wouldn't know, the I was using some maps the other day, we shot the probes ourself, and was using them for temporary background as well, and didn't have the problem. maybe you are better off with a different projection method.

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