my rendering stopped

[Anonymous]

I was doing a rendering approximately 4000x3000 pixels and after approximately 36 hours of rendering on a G5 Imac, I started to wonder why it was taking so long (one the same size took only 14 hours the other day)
I thought perhaps I had accidently made it 3000dpi instead of 300 or something really stupid. This is where I made the mistake of opening up the photorendering settings. It turned out my settings were correct, but opening them up made the rendering stop. The rendering was almost finished and I dont have another 48 hours to try again.
Is there a way to do a partial rendering in lightworks so I could combine them in photoshop. I really dont have 48 hourse to waste again and lightworks has already taken away hundreds of hours more than other applications would; setting up materials and having to make heaps of test renderings.
Has anyone got any ideas for me to only render what I need?
It would be really great if I could just tell it to render to the window with my unfinished rendering still there and say render these pixels to these pixels (you could call the tool "finish what you started.. you incabable rendering engine...")
Anyone got any ideas? I know the Internal engine can do partial rendering.. but lightworks doesnt seem to be able to.

[Dwight]

You can't solve this one. You can re-aim a new rendering and merge it with the old one. Not so bad in an emergency.

Opening the settings stops the rendering. Fastest way to do it.

The reason it doesn't render like the old engine does is that the rendering method creates a ray tracing "solution" first, then produces the image afterward. More wholistic than the old way.

Suggestion: make a smaller rendering. Who will notice?

As for unexpected extra time:

1: this rendering might have many more polygons.
2: there might be overlapping refractive elements.
3: Ram available and disk space affect rendering time...
4: small changes in sunobject setting can add time....

[Anonymous]

Thanks dwight. I am trying rendering the bit it didnt finish by reducing the 3D window height and scrolling to the bottom and then adjusting the rendering window height. It should be easy to join in photoshop. Failing that I will reduce the resolution (you're right no one will notice the difference between 300dpi and 180dpi)... I guess I just never expected it to take so long

[Dwight]

4000x3000 is 4x the size of 2000x1500

[Erika Epstein]

Neil,
If you haven't already you should order Dwight's new book. He goes through many way to evaluate a rendering before you start to, among other goals, avoid unnecessarily long rendering times.

The list he started above are just some of the more [after reading it] obvious places to look!

[Dwight]

Thank you, Erika.

Since I leave on Tuesday for a month of lecturing in New Zealand (Los Angeles and possibly Honolulu - bug Rex), ArchiCAD TALKERS who want to support this book project should order directly from me using PAYPAL before the weekend.

This book solves problems you don't even know you have with simple setups for lighting and materials in exterior and interior situations....

We will send orders Monday.

If you order during my absence, your order will be sent on November 16 - plenty of time for Christmas - an excellent gift.