Rendering material blocky

[archbaech]

Whenever I render, I seem to always get some materials which show up as blocky patterns, Like a Modrian painting. What am I doing wrong. What rendering seting controls this. See attached images. Some materials render correctly , others are a mess.

see walls on industrial building. These are suppose to be metal siding material

See mullions on interior rendering. This is suppose to be mahogany material

[ntellery]

I'd guess you have two componants occupying the same space. so 2 different materials (or even the same one) are competing to be rendered.  Nice pics.  How did you get such great lighting inside.  My efforts are miserable.

[archbaech]

Victoria at Subsrciption Support Services figured it out.  I had shrink wrap turned on. It was competing with the base material. I'm still not sure what shrink wrap does.  Once I turned  it off the problem went away.

Lighting has taken me 15 years of excrutiating time consuming trial and error. Each rendering takes hours and hours of experimention to get it somewhat right.  There are so many variables that anything can go wrong. Wierd and strange things happen reguarily.  You just have to grit your teeth and keep plugging away.

My best advice is only change one variable at a time. Do a low rending, evaluate it, then change the same variable again until it does what you want.

Keep a notebook to remember what you change and what the effect was.

Make sure the room is enclosed on all sides, top and bottom to make a completely dark box seperated from the great display light above.

Put a camera inside the box set the hieght at 6 ft, aim it and adust the angles.

Whenever you select, named view/ camera view - always update layers before set current

Start with one light a time in the dark room. Once you get it right - copy it to other locations. (such as in a fluorescent light grid).

Rename all your lights and group the same ones by room name and light type  such as  Office A Fluor 1,  Office A Fluor 2...  Accent 1, Accent 2... Rm B Downlight 1, Rm B Downlight 2, Rm B Downlight 3....

Now you can adjust all the same type of lights in the room at one time ( like when you turn on a switch in the room and ten lights come on)

Use the light list, highlight all the lights in one group (like on one switch). select properties.  Change one variable, such as intensity, run a new low rendering, check it out, Do the same thing again, change a variable, again, and again  until its just right, then turn off those lights and  work on a differnt group of lights. 

It takes less time to experiment if you set low rendering to crop- then use the window only to select and render the area where one light is.

Keep a folder called Test Renderings. Save files such as:   point light 7 ft_ target 2ft_2200CD_ intensity 1.500 too bright .jpg   Lamp color Cool Flour.jpg or other names which help you remember what you changed and what happened. These will help for future frustrations. save them

Once you think you get it just right, run a high rendering , or presentation rendering,  It usually takes about 6 to 10 hours.  Go work on another computer or go Listen to some good music.  You deserve it!

Then the next morning, when the rendering is  finally complete, you will find some other anomoly and you will have to start all over again!