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grafxstudio
10-14-2014, 06:31 AM
Is there a setting to make a black light? Or is there a way to fake it in Lightwave?
grafxstudio

Sensei
10-14-2014, 07:24 AM
Black light??

Black color is lack of light, lack of photons at all visible wavelengths..

In old times people were using "negative light", negative value of intensity, to subtract light from some surface.
Not sure whether it will give you wanted effect.
(it has nothing to do with reality)

50one
10-14-2014, 07:27 AM
yup, if looking for negative light than inversed intensity is what you are after.
If you;re looking for UV light than it's a completely different subject.

gerry_g
10-14-2014, 07:32 AM
give it a negative value, say -100 = absolute black, that simple

- - - Updated - - -

and if you add a colour to the light you will get its opposite

MarcusM
10-14-2014, 07:50 AM
Looks like Spotlight with -100% to -1000% Intensity and turn off shadows giving nice black cone.

raw-m
10-14-2014, 08:49 AM
erikals did this not so long ago, might be useful (might not!).

http://www.youtube.com/watch?v=pllhOF6xuyk&list=PLD495DCA5001810EB

XswampyX
10-14-2014, 11:15 AM
This kind of light?


https://www.youtube.com/watch?v=zcJo1lbGe1U

Amurrell
10-14-2014, 03:11 PM
I'm pretty sure the op was looking for a UV light. In the states we sometimes call these "black lights". I'm sure swampy's on the right track.

Chrusion
10-14-2014, 08:58 PM
Agree with swampy and amurrell as to the OP's original intent. If so, then it's all about surfacing... saturated colors, luminousity maps matching the "painted" surfaces to make just those areas "glow," and a dark scene. Illuminate using an indigo colored light to tint all surfaces indigo (including anything white or neutral).

spherical
10-14-2014, 10:21 PM
Agree with swampy and amurrell as to the OP's original intent.

Yep. Those other guys need to get out more. :D

jeric_synergy
10-14-2014, 11:56 PM
FWIW, I've always called LW negative value lights "darklights".


(Not to be confused with "dedlights", which are viewpoint placeholders.)

danielkaiser
10-15-2014, 03:19 PM
Yep. Those other guys need to get out more. :D

Not all of us grew up in the 70's

spherical
10-15-2014, 06:24 PM
I feel for those who missed it.

Then again, some of us never grew up. I feel for the ones who did.

jeric_synergy
10-15-2014, 08:14 PM
Not all of us grew up in the 70's

ROTFL. Yeahhhhh, that's true. :thumbsup:

grafxstudio
10-18-2014, 09:37 AM
The reason I'm asking is because I thought I would get into the Halloween spirit and do a haunted house. Can we envelope the point light fast enough to do a strobe?
grafxstudio

grafxstudio
10-18-2014, 09:53 AM
I found a video that explained it by William Vaugn

jeric_synergy
10-18-2014, 10:37 AM
I found a video that explained it by William Vaugn
Which bit, the strobe or the UV?

To save you quite a bit of linking, look at this thread: just skip down to posts by the inimitable XSwampyX to find excellent examples of UV lighting via nodes in LW. http://forums.newtek.com/showthread.php?138201-quot-Magic-Lights-quot-useful-aka-quot-X-channel-Light-quot-nodal-applications-extended-spectrum/page1

grafxstudio
10-18-2014, 03:02 PM
Now I saw a video on making a candle flicker. I thought that video plus adding speed would make a strobe but just tried it and couldn't get it to work

jeric_synergy
10-18-2014, 03:15 PM
Things to consider:

1) Envelope keyframes should be STEPPED.

2) Your strobe timing may run afoul of the frame rate. Weird things can happen with strobes: https://www.youtube.com/watch?v=RB0LYbKLrBw

Chrusion
10-23-2014, 09:03 PM
Since you can't keyframe anything alternating at a rate or frequency faster than the frame rate of the animation (eg. 80 flashes/sec in a 30 fps anim), the best you can do is turn the light on for 1 frame and off for the next and repeat the envelope. This would obviously give you a very noticeable/visible, 15 Hz flash rate. You could minimize the on/off distraction by not turning the light totally off, but setting it to 50% or something.

If you use fractional frames, then you'll get an undulating brightening and darkening of the staccato flickering... IOW, a temporal beat-pattern.

grafxstudio
11-05-2014, 08:16 AM
I had to put this on the backburner for a while so now I'm beginning again. What I was wondering if I did a animation with the lights flashing and then do another without the lights and then combine them would I get a realistic strobe light in my animation?

Chrusion
11-12-2014, 03:06 PM
What would be the purpose in doing it that way?

The fastest strobe you can get is 15 fps (if anim is at 30 fps). So, just animate the light intensity on/100% for frame 0, off/0% for frame 1, set keys to stepped, set post behavior to repeat, and render.

spherical
11-12-2014, 08:22 PM
...and send some unsuspecting soul into a seizure. :)

Chrusion
11-13-2014, 06:10 AM
LOL... yep, you would want a fair amount of fill lighting or not reduce the strobe light to 0% in order to "smooth" out the flicker. Also, strobes and flashing anything tends to make .h264 compressors very unhappy... even worse when mixed with confetti.

pinkmouse
11-13-2014, 06:25 AM
Back in the day, I used to try and run strobes at two or three times the BPM of the track for best effect. So for your average 140BPM Hard Trance track, I'd be running between about 4 and 7 flashes per second.

Still working on my multiple mirror ball effects... :D

Silkrooster
11-24-2014, 02:45 AM
Ok, I missed something, how did the subject get onto strobe lighting, when it was about black lights? No where near the same thing.