Anim8or Community

General Category => General Anim8or Forum => Topic started by: AlecJames on February 14, 2017, 03:49:05 pm

Title: How do I get the image I started with?
Post by: AlecJames on February 14, 2017, 03:49:05 pm

I've just started looking at this by trial and error but which settings should I be looking at:

Object - cube 192x108x2, 192x108 face has a material from an image (16 shades of grey test image), put the cube in a scene, centre the camera in the middle of the image 200 away, change FOV so the image (1920x1080) exactly fills the camera, render (I used scanline), save the image.

When I compare the rendered image to the image used on the material (I want them to be identical), the rendered image is darker then the original. 

What is the best way to get a perfect match?  (which material settings / lighting settings / etc.?)

(I'm experimenting using anim8or to create custom video editor transitions) 
edit: Attachment - with an infinite light (default settings) at the same location as the camera.  Top is the original image, bottom is the rendered image. Black matches but the lightest shade is darker.
thanks 

Title: Re: How do I get the image I started with?
Post by: Steve on February 14, 2017, 07:54:43 pm

To best match flat colors like these, you need to make a material with the ambient and specular weights of 0.0, the diffuse weight of 1.0. Using this image as the diffuse texture, apply it to a cube in the Object editor.
Then, in the Scene editor, add the object and a white light, color 255, 255, 255 and point it directly at the cube.

Here's a ART render of this. The colors in your original image gray scale range from 0=black to 240=white. In the render I posted the range is 0 to 239.

Note: You need to rename the image that you posted from Comparison.png to gray_scale.png for this project to work.

Title: Re: How do I get the image I started with?
Post by: AlecJames on February 15, 2017, 04:11:26 pm

Thanks Steve

I messed with it last night and concluded that I was trying to do something that it just wasn't designed to do but your suggestions worked first time :)

I didn't explain very well, in my comparison the top half of the image is the texture file and the bottom half is the rendered result from Anim8or - I assembled them one over the other in paint.net so I could see any difference between texture in and render out by looking at the join.  I've attached the result with your settings - any imperfections caused because I didn't get FOV quite right for the cube to exactly fit the camera  frame.

Hopefully I'll finish the video I'm planning in a few weeks and I'll post the results.

Thanks again

Title: Re: How do I get the image I started with?
Post by: Steve on February 15, 2017, 06:40:40 pm

That's what I thought your first image was, I just used it as the texture because it was easy :-)

I'm glad you got the lighting to work as you wanted.
Note there is another way to do this. You can set the diffuse, ambient and specular weights to 0.0 and the emissive weight to 1.0, then add the texture to the emissive channel. This will remove lighting from the render altogether.