Vegas uses the bitrate it needs, up to the target or upper limit.

To do otherwise would defeat the purpose of interframe compression.

Do this: encode a sideshow with straight cuts and set the target bitrate where it is now, at 26 Mbps. Note the encoded bitrate and you will see exactly what we are talking about.

Okay, but how do I then get a better quality video? I mean even though it takes off like 40%, the quality of the video is getting better (15 -> 9 MB, 20 -> 12 MB, 26 - 15 MB).

I mean yeah, it should, the bitrate is increasing, but if 15 would really be 15 I wouldn't need to use 26 at first.

I've been reading a ton of stuff about codecs/container/best settings now and my head is burning.
Does anyone of you know why my videos get 40% longer as they should be?
Or do you have a link/instruction on good render settings?
I'll literally take anything and try it out. I tried Avi with x.264/H.264, all was great but then I noticed a delay of the video, it's black for a second and the audio starts 2 seconds in, which causes a delay...

What worked well was:
(for all I tried to aim for 14-18MB, 1080p@60FPS)
Mainconcept Mp4 <-- everything is "good", but nothing is like really good
> Filesize is good, Quality is good, Render time is ok
SonyAVC Mp4
> Filesize is great, Quality is good, Render time is great <- Problem is the additional length of the video, Youtube stops at 5% upload, guess it can't handle the problem :/
Windows Media Video Wmv
> Filesize is great, Quality is good, Render time is hell

Okay, but how do I then get a better quality video?

https://www.vegascreativesoftware.info/us/forum/faq-how-can-i-improve-the-quality-of-my-avc-h-264-renders--104642/

Thanks, I'll go with the Sony AVC and hope I can put in the settings you want someone to have...I have a bad feeling I did mess up with unticking a box or forgetting one, like maybe even in the properties, but I'll read it carefully once I am home.

Short question: I have SVP11 and SVP13, I noticed doing exactly the same is faster in SVP11, while SVP11 seems to be a bit...unstable. Might be just bad luck. Any tips?

My Specs are I7-2.6GHz, 8GB Ram, NVIDIA GeForce GTX 860M.

As you can see those specs aren't great, that's why I try to change the settings I am using. I am willing to take quality all over anything else, but right now I render a 1 minute video in 9+ minutes, meaning a normal video with 15 minutes would take 135minutes...then there is the upload. I try to find a balance with focus on quality, low render time and low size for faster uploads. I know there is no perfect solution for everything, but I noticed some codecs render longer with same file size and worse quality.

Short question: I have SVP11 and SVP13, I noticed doing exactly the same is faster in SVP11, while SVP11 seems to be a bit...unstable.

Did you mean SVP13? All I can think of is a thorough like-for-like comparison of your VP11-vs-VP13 settings. A reinstall perhaps but that's a bit drastic. You could try a free 30-day trial of VP14. Lots of bugs have been fixed, although not really anything that should improve performance over VP13.

Nono, it was explained to me like this: Newer versions are created for better computers, that's where a big increase in render time is coming from in newer versions (like, when you do exactly the same). That's why I prefer 11 a lot, I'd love to test 10 but meh, money and seems impossible to find xD So, for doing the "simple" Youtube-Videos of Minecraft, I don't need a lot of extras (except for Computer RGB in Studio RGB, but that's just a filter)

Problem: 11 seems to be a bit unstable. Sometimes when I render the progress bar stays at 0%, estimated time inceases to infinite amount until I kill the process. Sometimes a full video is just black, randomly, nothing changed. But reducing render time by 50-70% is worth it for me...

One last thing:
When I render a video for Minecraft my main problem is the grass (a block all over the ground) seems blurry. I barely see the pixels on the grass (a block has 32x32 resolution). That's what I am trying to change. As soon as I stop moving it takes 1-3 seconds and the grass looks awesome, no blur, but I want that aswell while moving.
Any idea how to solve that? More as 26 is not possible with Sony AVC, and with MainConcept even using 20-30 (average/max) is not helping it looks like. I assume my presets are somewhat wrong or I don't know what's going on. Or maybe I just want to much that's not worth it..

I'll try out x264 encoder, I have it for Avi but I assume I have a weird one. As mentioned, if I encode with the x264 I have or pretty much any of those with 264 in it (H.264, h.264...) the sound is asynchron to the video by 1 second. Like if I hit the ground you hear it before it happens. The video is also black the first second which explains the delay I guess - audio is on time, but video is delayed :/ Man, why can't everything just go right once xD I'll try 2, 3 and 4 of your post this evening :)

Edit: I hope I will understand everything right of your post, I have trouble understanding specific words, my mother language is german and even though I'd say I can speak english well, some words that I never used before are unknown for me, like I see them, I can associate settings with them (sometimes), but I don't know what it means. Like if you see "bitrate" and you know that means the value afterwards defines the quality of your video, but you don't understand what it actually means/does (the word and what you are doing). The thing I am scared of is copying all I see from what you posted, but misunderstanding something or missing out on something that seems to be obvious. I'll reply once I did the testing and maybe send you different outcomes on Youtube if that's ok!

https://translate.google.com/translate?sl=en&tl=de&js=y&prev=_t&hl=en&ie=UTF-8&u=https%3A%2F%2Fwww.vegascreativesoftware.info%2Fus%2Fforum%2Ffaq-how-can-i-improve-the-quality-of-my-avc-h-264-renders--104642%2F