Oxidizer 0.4.2: Scale and Zoom Settings

by Scott Chitwood • Friday December 28th, 2007
Posted in Tips and Tricks, Using Oxidizer

Reading through my tutorial for Oxidizer 0.3 there is a note that states…

It will be necessary to adjust the ‘Zoom’ setting in order to fill the working canvas once the image size has been altered so dramatically from the 128×128 default. Zooming somewhere between 3.4 – 4.2 has worked very well for my renders, but don’t let that limit your explorations of how much or how little zoom to use.

With the release of Oxidizer 0.4.2 it is time to adjust that idea, and with good reason.

Using the idea of ‘Zoom’ in 0.4.2 as described above requires a tremendous amount of processing power, enough to adversely effect the operating system and other apps to the point of just barely crawling along. The flame may eventually render, or it might bring Oxidizer to its knees. Crash and burn kids, and that isn’t fun no matter how you dice it. The other reason you’ll want to avoid this method is extremely long render times; I have personal experience with renders that have taken several days only to find my design effort was less than what I had envisioned.

One might ask why I chose ‘Zoom’ over ‘Scale’ for that earlier tutorial and personal work method. I’m guessing that it just happened to be the setting I tried first and then stuck with as a good default.

So what are the differences between ‘Zoom’ and ‘Scale’? Good question. I’m not sure if I can answer it properly from the point of the math concepts/coding but I can answer it from a visual perspective.

Used independently from one another it’s easy to see that ‘Zoom’ is the clear winner for capturing a more detailed render. ‘Scale’ certainly helps one find desired cropping and position of the flame in preview mode but it has the appearance of a low resolution image; grainy, lacking detail and out of focus. Bleh.

Obviously we need to use both ‘Zoom’ and ‘Scale’ together to find the proper balance of image detail and flam3 settings that won’t adversely effect your operating system. For me, this starts with linking ‘Scale’ to image height. Here’s a look at my current workflow methods.

I’ve recently adopted a widescreen image ratio for all of my still renders, the size is 3360×2100 pixels. Before changing the image ratio I make sure to check the ‘Lock to Height’ option next to the ‘Scale’ setting.

Now it’s time to make adjustments to both ‘Scale’ and ‘Zoom’. Deselect the ‘Lock to Height’ checkbox. Change ‘Zoom’ setting to ‘1.5’ and change ‘Scale’ setting to half of value displayed.

Switch over to the ‘Render’ settings and change ‘Quality’ to ‘800.00’ from default of ‘50.00’.

The end result should be an image that has a good amount of detail that will render without overloading your processing power. Images below show the quality sequence of a flame as it was pushed through the details noted above.

Scale or Zoom Tutorial


  1. David Burnett
         December 28, 2007

    The difference between zoom and scale (for all intents and purposes) is that zoom adjusts the quality to make up for zooming in.

    The adjustment it makes is quality -> quality * (2 ^ zoom) * (2 ^ zoom)

    So for example with a quality of 100 and a zoom of 4 you’re doing the same as rendering with a zoom of 0, the scale divided by 16 to match the framing and the quality set to 100 * 16 * 16 = 25,600

    In your example Scott, that’s 800 * 8 = 6,400. You can see where the reduction in CPU is coming from.

  2. Pharmagician
         December 29, 2007

    Very cool, simple, high-quality application… Will there ever be a resizable preview window? It’s a little small to see detail while editing. Also a render progress bar and a cancel/stop render process button would be useful. But I love it and the results are amazing! Thanks!

  3. Pharmagician
         January 1, 2008

    More… so here I am, on my antediluvian, diddy G3 600Mhz iBook, and I just made a Grand Julia(n) with this amazing software. I need to work out how to sharpen the image – another gentle plea here for a bigger or resizable preview window (or am I missing something glaringly obvious?). What a great app!

  4. Ralf
         January 2, 2008

    The Render Window (cmd-shift-R) can be resized, just click and drag the lower left corner, then change the global “Size Scale” setting on the main “Environment” tab to fill the view.

    To sharpen the image you need to play both with the “quality” setting (=high) and the oversampling and (density) estimation parameters on the Flame->Render tab. Try changing the estimator radius between 4-9, and the estimator curve between 0.4-1.5, and you’ll see what it does :)

  5. Ralf
         January 2, 2008

    Sorry that’s lower *right* corner….

  6. Pharmagician
         January 2, 2008

    Thanks! Will spend all evening experimenting… ;-)

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