Guild hall summoning

[Kunoichi]

Hello
I'm a guild leader twice in a week we do the summoning at the guild hall for that I use the 100 Eidolon Energy Crystal each and everytime I get the lowest eidolons levels (like 50 60 70) while some others get strong and powerful eidolons (like 80 90 with a shield) and we all use the same EEC I tried to search on google but I couldn't find anything is it random? should I give something else to the Researcher? Thank you for your kind answers

[Spella]

Yes it's random.