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Exception
01-29-2008, 11:22 PM
Well, the guys over in the beta forum forced me to do this by threatening to drown a dozen kittens and bombard me with Jaffa cakes...
So here is a small Linear work flow / HDR and Virtual darkroom guide that also covers blooming / corona.

I hope you'll enjoy it... you scum! ;)

http://www.except.nl/lightwave/hdr/

Cheers,
Tom

Limbus
01-30-2008, 02:35 AM
Very cool. Thanks a bunch. I will sacrifice a cat to honor you at midnight. May it bring you health, luck and pockets full of cash.

Cheers Florian

Lewis
01-30-2008, 02:38 AM
Great as usually :D :D.

Red_Oddity
01-30-2008, 07:32 AM
Not sure everyone can read the threads posted at the Open Beta forum, so i'll just post it here aswell:




Nice, we have some rules when working with linear workflows (for example converting textures from AdobeRGB / sRGB to linear gamma corrected textures, making sure we use gamma corrected colors (usually by changing picked colors with 0.45))

And offcourse using a gamma calibrated monitor to help you with your linear (test) renders.



What also helps alot instead of setting your display gamma to 2.2 as above (to prevent you from going nuts from working with a foggy interface) is :

1] Create a plane,
2] Parent that to your camera (close to the pinhole position of the camera) and making sure it covers the entire view,
3] Assign the attached surface to the parented plane.

This gives you realtime gamma corrected FPrime and LW renders.



How sad, i'm actually quoting my self...anyhoo...have fun, and thanks again Exception.

RollerJesus
01-30-2008, 07:49 AM
Really appreciate this.

JeffrySG
01-30-2008, 08:00 AM
Going through it now. Seems most excellent!

Thanks so much!! :D

Matt
01-30-2008, 08:06 AM
Great tutorial Tom, you have a good way of cutting through to the heart of the matter!

RollerJesus
02-01-2008, 12:37 PM
Hey Tom,

I was going throught the steps on your site and noticed that when I loaded up your gallery image in PS and tried to adjust the gamma to match as in this section:

To see it the same way it was rendered set the Gamma in the 'exposure' adjustment tool to 0.5. (located under Image > Adjustment > Exposure in PS CS3).

I needed to set it to 1.5 (Instead of 0.5) to get a match. Typo?

`Patrick

bgraves44
02-01-2008, 05:12 PM
Thanks very much!

B

Exception
02-03-2008, 03:07 PM
I needed to set it to 1.5 (Instead of 0.5) to get a match. Typo?



Hey Patrick,

No that is not a typo, but there are two exposure controls in Ps which are confusing.
One is in adjustment > exposure, and the other one pops up when you convert from 32 bits to 8 bits. This last one is reversed, and kinda odd.

RollerJesus
02-06-2008, 08:53 PM
Thanks for clarifying. I was a bit bewildered.

Goldfinger
02-08-2008, 05:44 AM
Great Tutorial, learnt so much about the image editor which I didn't know existed!...One thing I didn't understand was how I can apply this to a sequence of images for an Fprime animation...Usually I output the images as tga, then put togeter in virtualdub, then save as avi and bloom in comp...It seems the LW image editor has way more control so I'd like to try using it more for animations.

Thanks again for the tutorial, :thumbsup:

ary3d
02-18-2008, 09:36 PM
Excellent tut!!!, I try this and came up with awesome results, thanks for the enlightenment.

greetings, David

archijam
02-19-2008, 02:00 AM
Nice, tom! :)

j.

Exception
02-19-2008, 07:43 AM
Great Tutorial, learnt so much about the image editor which I didn't know existed!...One thing I didn't understand was how I can apply this to a sequence of images for an Fprime animation...Usually I output the images as tga, then put togeter in virtualdub, then save as avi and bloom in comp...It seems the LW image editor has way more control so I'd like to try using it more for animations.

Just load in the first image of your image sequence and set the image type to sequence. Then Lw will treat the entire image sequence with the adjustments. Not unlike virtual Dub.
Then put the image sequence in the backdrop and set the camera res to the same res as the image sequence, then render out a new sequence, or directly to animation.

crashnburn
02-19-2008, 08:41 AM
Thanks a lot, interesting and helpful.....appreciated.

Thomas M.
02-19-2008, 09:41 AM
Nice little tut! I hoped to find something on pre-adjusting PS images, e.g. in Adobe RGB space, to fit into this workflow. As long as you stay in LW this doesn't matter too much, but if there's the need for image maps, the gamma needs to be set to 1 before pumping these into the linear workflow. Any chance to hear a few words on this subject?

Cheers
Thomas

Exception
02-19-2008, 10:07 AM
Nice little tut! I hoped to find something on pre-adjusting PS images, e.g. in Adobe RGB space, to fit into this workflow. As long as you stay in LW this doesn't matter too much, but if there's the need for image maps, the gamma needs to be set to 1 before pumping these into the linear workflow. Any chance to hear a few words on this subject?


Well, when I was announcing the half-done tutorial I intended to write a full linear workflow tutorial. I ended up doing only a HDR post proccessing one, as I didn't have the time to go into linear workflows... so the topic of this forum is wrong :)

Linear workflows require an extensive explanation, there' snot a simple answer to this, besides saying that you can use the FP gamma filter for incoming images...
I hear there's a good guide in HDRI magazine #18, but I haven't seen it yet.
Graham has nice tips on his page about this subject here:
http://www.happy-digital.com/freebies/tip_gamma.html

Goldfinger
02-26-2008, 09:24 AM
Thanks Exception for helping with the animated sequence question, very useful! I only seem to get a colour depth of 96bits, instead of 128 when I load in Fprime rendered .exr files....I have the FP viewer on in render globals options...Is this normal or am I missing something simple?

Thanks again

Limbus
02-26-2008, 09:51 AM
I only seem to get a colour depth of 96bits, instead of 128 when I load in Fprime rendered .exr files....I have the FP viewer on in render globals options...Is this normal or am I missing something simple?


You are missing the alpha channel.

Goldfinger
02-26-2008, 10:00 AM
Thanks Florian:thumbsup:

Turns out to be simple!