@lebrun78 OK I just had a chat with the developers over this.
zstd is used for decompression of both legacy and new images (as of FOG 1.3.5). You have the option of using industry standard gzip for image compression or the new zstd for image compression. If the industry standard gzip compression is used, you “could use” any zip program to extract the image from the FOG archive (not very common and only done for a very specific reason).
The newer zstd format can achieve better data throughput (target hard drive compression and decompression) than by using the gzip format. They (the developers) switched to zstd based on a feature request to make FOG imaging even faster (the FOG Project is all about going faster) and with a tighter packed image on the FOG server (smaller disk space used on the FOG server’s hard drive).
The real decision not really a decision. Use zstd and live with the faster deployment speeds, or use gzip and deploy as the same zippy speeds the previous versions of FOG 1.3.x supported.
Really its not a decision use zstd and worry about other things in the world.
I wasn’t aware of needing the client for sysprep, so I will try that as well. I’m still learning (aren’t we all?).
Just for clarity, the fog client is only needed if you want fog to connect the target system to AD, rename the computer what fog has defined as a system name, and deploy snapins. Its not mandatory to have the fog client installed in the target image. Why we both mentioned it is we have seen issues where/when the fog client IS installed and not properly setup, the rename action takes place before the OOBE setup is complete and breaks the deployment.
If you captured the image in legacy mode, you may not deploy it to a computer in uefi mode. You need to create yoru image in uefi mode, capture it and deploy it to a uefi computer.
If I can give you some advice. Build your reference image in a VM and use MDT (microsoft deployment toolkit) to create your reference image. I know it will take you much longer on the first one to get to a capture. But in the long run you can create a universal image that will work for any hardware (with a few fog tweaks).