Quality of compressed x264 recordings vs using slower x264 preset


New Member
Hi, I have a question regarding two scenarios.

So in the first scenario, let's say I use x264 superfast with CRF 18 and I am recording in 4K 60fps, this gameplay recording will be a huge file since the CRF is quite low. Then I proceed to compress this video to some variable bitrate, for this example, I'll just say the target is around 70000 kbps and the file size is about 1GB. In the second scenario, let's just say I use x264 faster with same CRF 18 settings recording in 4K 60fps. Now I know CRF is constant quality and that the bitrate and file size varies wildly, but let's just say that in this second scenario, the recording coincidentally is also around 70000 kbps on average and about 1GB in size.

If we then compare the compressed 1GB video recorded using a faster x264 preset in the first scenario with the raw recorded 1GB video using a slower x264 preset, will those two videos look the same? That is to say will they have the same quality? And also, does the compression tool/method matter as well? Like does handbrake vs adobe matter?