I use this option quite often. But it creates a very low res. jpg. Is there a setting in vegas to set this to a higher resolution? Prefer 1920x1080 dpi 0f 300 or better. I could do it in PSP but the quality suffers.
Yes, I always use PNG or clipboard. PNG is better than JPEG for snapshots.
In most cases since VP9.0d a temporary "Best (Full)" is set automatically when taking a snapshot, but not if your preview is set to Half or Quarter. From the VP9.0d release notes: "Copy Snapshot to Clipboard and Save Snapshot to File now deinterlace interlaced images and operate at Best (Full) resolution if the Video Preview is set to (Auto) size and Good quality if set to Draft or Preview."