Confusing,.. keyframing and that curve editor thing

please take a moment to read,…

has anyone here ever noticed, if you make a key frame of anything (colour, light intensity, size, rotation,etc), at maybe frame 1, and another at frame 100 , all the frame between that get messed up.

So , for example, a light with a certain intensity at frame 1, and then another frame at 100, with a higher intensity, between these frames (1 and 100) the light intensity goes up and down, and this means the entire scene or animtion gets complety ruined, i have a light in a 300 frame animation, to gradually get brighter, so intencity at 1, keyframed at frame 1, the intencity at 4 keyframed at frame 100, and the light does not get intence, it goes up over 7, below 0, and there’s nothing i can do about it,

same with procedual textures, like clouds for example i use key framing to make the two colours of the cloud texture to change over a hundred frames, with nor of 3, and what happens? every single slider goes up and down in every direction imaginable,

so the only way around this is to edit them in the IPO curve editor , which does not help becuase the sliders are more aaccurate, so i have to live with this or put in a key frame for every frame.

this must be a bug, sometimes everything works, but most of the time, everything between the keyframes has a mind of it’s own.

try doing animations of textures and lights changing different colours many times, (say red for first 30 frames, for example, on object of choice) and you may start to notice that everything goes wrong

please help me, is this meant to happen, or am i the only one who is effected, i hope not, because i need to be able to do this properly

if anyone has any idea of what i am talking about, and can help, it would be great


joe goss

not entirely sure if i got you right.but let’s try.

if you make just two keyframes, one at frame 1 (value=10) and one at frame 20 (value=100), you’ll get a nice ascending curve with a steady change. if you add a third keyframe at frame 25 with a value=-20, the curve section right before keyframe 2 (@20) will probably slightly exceed the value of 100. maybe that is what you mean by “screwed up”.

you can easily fix this by entering edit mode of the IPO-curve affected and tweaking the tangents. you can also select a point and change handle types (use the keys “H”, “V”), or use the snap menu (SHIFT+S>>“Horizontal”).

however, there’s no need at all to add a keyframe at every frame - you can always tweak the curves to match your needs.

hope that helps

hmm, helps a little, but not really, in fact i am proberly going to be the only one affected by this problem, because nothing ever works for


here is a clear example of how things went horribly wrong

a light (area) intencity at a value of 1.0, and a key frame for this for frame 1. now another key frame at frame 290, still, 1.0 is the intencity level of my light, and a third key frame at 300 (10 frames later), now the intencity is 5.0

so the idea was the light stayed at 1 for 290 frames, and for the last 10 frames the light became much brighter

what went wrong, the light never stayed at 1 for those 290 frames, it went down to -0.20, and up to 8.82 a few times, then went to five and the end, really does not make my animation look nice.

why’s this happen?, why me?

Joe Goss

well what i said should help - go to the second keyframe, enter edit mode, select the vertex at that keyframe, hit shift+s>>horizontal. this will make the section between kf1 and kf2 prefectly flat. then, during the next ten frames, the curve should grow up steadily until it reaches the value of 5. if you have keyframes AFTER that, they might screw things up. if you don’t need them, go delete them, if you do, go tweak the tangents.

You must change the handletype for the IPO curve, as standard it is set “Auto Aligned” which will make the curve smooth throught all points.

Heres you curve:

And here’s what you get:

oh cool, i’ll try that in a hour when i ge my computer back (rendering at the moment, this not my computer)

thankyou for helping solmax and eric, i’ll get back to see if everything went well


Joe Goss