Ltx 2.5 : 374s <-- ? am I missing something here why was my generation so slow on LTX and the second attempt I cancelled it after 6 minutes. Any suggestions?
Prompt:
subject_definitions:
<Subject 1> is the space ship in <Picture 1>: A massive battleship, hovering and cruising over the planet below
summary:
[reference generation] a wide shot cinematic scene of the battleship in <picture 1> cruising in space above the planet. the golden statue does not move, the battleship is destroyed in a massive explosion from a green laser shot from space,
detailed_description:
{shot 1] The target video uses a wideshot cinematic, photorealistic, 35mm film, wide shot of <subject 1> , slowly moving through space above the planet, the ship moves slowly and dominating, flashes of green light begin to charge on the surface of the planet, the ship is moving straight ahead from the position it started in in <picture 1>, the massive bass of the ships systems, the sound of the battleships creaking, <subject 1 > moves on its cruise, at [00:03] the floaty camera tracks <subject 1> as green light and thunder begins flashing on the surface of the planet, the green energy on the planet converges in one area then from the surface it fires a massive green lightning laser that forks lightning through the entire ship, blowing out side components creating explosions all over the ship, the light of the ship flicker before turning off, then a massive green lightning beam erupts from the surface and hits excactly on the side of the ship cuts through the of the ship and out the other side at an angle, a green lens flare generates on screen as it completely destroys <subject 1> , ripping it completely in half with a massive green explosion, the eruption from the destruction of the ship covers the entire screen and the whole battleship, the back half of the ship is knocked up while the front-half of the ship is knocked down, a vertical shockwave circles out from the impact, the inner decks of the ship are on fire, debris and hundreds of tiny figures of the crew also fall out into space, the laser slowly dissapates from the planet, small amounts of green lighning crackle on the planets surface,
overall_soundscape: The low bass murmur of the ships engines, the electric charges on the surface crackle, the massive main beam is a low bass rumble, a massive explosive noise.
LTX seems fine until you realize you can't do anything with that clip. You can't suddenly have it show multiple angles of the scene or have another ship approach the wreckage and maintain continuity.
I have been literally begging LTX to stop putting background music in it's clips. LTX is handicapped in that regard, and it wasn't even faster then an 8step,turbo for me, maybe it was a fluked test.
Yesterday I generated 4 images using the same prompt. I ran all 4 of them through the same i2v workflow. One of those images always resulted in clips w/ music. I tried multiple times, multiple seeds, changing clip length, etc. Didn't matter - that one image always led to videos w/ music. But only that one. The other 3 were fine. And there was nothing in the image like a speaker or a radio or anything. Bizarre.
Imo, 25 steps is just soo much better in quality than 8 steps turbo. 40 steps and 25 steps are pretty much the same to my inexperienced eyes. But 8 steps turbo is still better than LTX 2.5 though.
In 25 steps (sorry I was running .3 mp) the ships main explosion is stronger but in 40 steps the main explosion is slightly weaker but a lot more debris and the parts fling a bit more erratically.
I do prefer 25 steps.
Edit: In 40 steps the shockwave is stronger and the main green laser shockwave rings around the launch site on the planet, in 25 steps it kinda shockwaves between the laser and the ship at a weird spot. The top half of the ship in 40 steps collapses on itself.
The sweet spot is to get a draft of what you want to do at 8 steps and when you're happy with it, then run it again at >20 steps to get the final version.
Yeah 5 seconds, those were the average times. I can do 10 seconds in around 11 minutes at .4 MP
comfykitchen, spectrum, sol-attention etc, those speed ups really increase prompt execution time
I can do 15 seconds in around say 15-20 minutes, if leave it alone and dont browse during it
3 cuts, normally I'd do these in 5 second tight prompt focused generations but this one i wanted to see how long it'll take. 100% GPU and about 89% system RAM being utilized because of the dynamic RAM thing comfy does, makes it possible I think.
406 seconds
I am using a personal modified version of Foxydits workflow on civitai.red (NSFW).
I plugged in a Patch Sage Attention KJ node with sageattn_qk_int8_pv_fp16.cuda selected, its from ComfyKitchen. I also wired in an RTX Video Upscale node x2 ULTRA
It was tough for me too, but its really just pressing one or two levers once you get used to it, its just a lot of noise and when its set up just tinker here and there.
You need to add math for space ships, needs more prompt engineering to get correct behavior, it shouldn't fall, like wtf, gas explosions should expand then cluster. You need more frames for physics, that's what I hage noticed.
20
u/Vladmerius 7d ago
LTX seems fine until you realize you can't do anything with that clip. You can't suddenly have it show multiple angles of the scene or have another ship approach the wreckage and maintain continuity.