Logo by chaos_crystal - Contribute your own Logo!

END OF AN ERA, FRACTALFORUMS.COM IS CONTINUED ON FRACTALFORUMS.ORG

it was a great time but no longer maintainable by c.Kleinhuis contact him for any data retrieval,
thanks and see you perhaps in 10 years again

this forum will stay online for reference
News: Visit the official fractalforums.com Youtube Channel
 
*
Welcome, Guest. Please login or register. September 17, 2019, 07:17:48 AM


Login with username, password and session length


The All New FractalForums is now in Public Beta Testing! Visit FractalForums.org and check it out!


Pages: [1]   Go Down
  Print  
Share this topic on DiggShare this topic on FacebookShare this topic on GoogleShare this topic on RedditShare this topic on StumbleUponShare this topic on Twitter
Author Topic: Mandelbulber 0.60 rendering problem  (Read 1359 times)
Description: 'Ink blots' in renders
0 Members and 1 Guest are viewing this topic.
MarkJayBee
Fractal Fertilizer
*****
Posts: 364



Markjaybee Fractal Mark_Jay_Bee
WWW
« on: June 02, 2010, 01:14:51 PM »

Hi guys,

I hate to bring this up - considering that I find Mandelbulber the best application for exploring the 3D
fractal 'realm' - but I've begun to encounter a wee problem with some renderings.
This takes the form of what look like dark 'ink blot' patterns in images rendered at various sizes, and using
different settings; ambient occlusion on or off, varied perspective and iteration count raised/lowered.
So far this only occurs when rendering deep zooms of Icosahedral K-IFS, but I will check out other
settings.
Obviously this is a little worrying when preparing an image which could take several hours to render!  sad
Any thoughts, suggestions or - even better! - solutions would be gratefully recieved!

Included 2 example images - 'blots' are on right of images: 


* image00010.jpg (233.42 KB, 640x310 - viewed 338 times.)

* image00011.jpg (234.03 KB, 640x310 - viewed 313 times.)
Logged

If at first you don't succeed, destroy all evidence that you ever tried in the first place.

http://markjaybeefractal.com/
http://mjb-graphics.co.uk/
http://deviantart.com/markjaybee/
Buddhi
Fractal Iambus
***
Posts: 895



WWW
« Reply #1 on: June 02, 2010, 03:20:33 PM »

These "ink blots" are caused by limited accuracy of distance estimation (used for calculation ray-marching step and finding fractal surface).Because this istance is only estimated value there are possible some oversteppings. This could appear also for other fractal formulas. Solution is very simple. Please reduce a little "DE step factor" value. Standard value is 1.0 (raymarching step = DE_step_factor * estimated distance). Maybe better will be 0.8 or lower. Lower value reduces overstepping problem but increases rendering time.
Logged

MarkJayBee
Fractal Fertilizer
*****
Posts: 364



Markjaybee Fractal Mark_Jay_Bee
WWW
« Reply #2 on: June 02, 2010, 09:55:53 PM »

Hi Buddhi,

Many thanks for the advice. I did as you suggested, and changed the DE step factor to 0.8,
and that seems to have done the trick!  cheesy

Now I just need to relocate the spot I was at when this started!!  wink
Logged

If at first you don't succeed, destroy all evidence that you ever tried in the first place.

http://markjaybeefractal.com/
http://mjb-graphics.co.uk/
http://deviantart.com/markjaybee/
Pages: [1]   Go Down
  Print  
 
Jump to:  

Related Topics
Subject Started by Replies Views Last post
Mandelbulber memory problem Mandelbulber Pauldelbrot 4 1474 Last post November 15, 2011, 01:15:06 PM
by taurus
Problem with positional light at stereo rendering bug reporting schizo 0 717 Last post December 06, 2012, 08:25:12 PM
by schizo
Problem with stereo rendering: Common vs. Rectilinear lense (v189) feature request schizo 1 1807 Last post July 08, 2016, 05:52:59 AM
by Rathinagiri
Mandelbrot Set Distance Estimator Rendering Problem UltraFractal aleph0 5 1414 Last post April 30, 2014, 01:08:45 AM
by aleph0
Rendering problem with Mandelbulb 3D Mandelbulb 3d OceanTemporal 1 2325 Last post October 30, 2014, 07:33:21 AM
by OceanTemporal

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines

Valid XHTML 1.0! Valid CSS! Dilber MC Theme by HarzeM
Page created in 0.097 seconds with 28 queries. (Pretty URLs adds 0.006s, 2q)