ATEM 1 & 2 GPI/TALLY INTERFACE BOX

On the ATEM 1 you can not run an SDI on input 1 to 4, Only HDMI correct.

Yes, that's true so far as it goes. If you need more than the four SDI inputs (#5-#8), you can use Blackmagic SDI to HDMI converters to run SDI feeds into inputs #1-#4 -- so it's no big deal to get up to eight SDI inputs on either the TVS or 1M/E versions. (Or I suppose you could do the opposite, and use HDMI to SDI converters and send up to eight HDMI feeds to the switcher.) Either way, there will be a tally for every one of the eight physical inputs, regardless of format.

-- Jeff