Measure to count items in table 1 but filtered across Table1 and Table2

[TASylbaryn]

I'm sure I'm missing somethinging here so any help would be appreciate. Also, happy to do the leg work myself if you can point me in the right direction. 

Table 1 is linked to Table 2 (1 to many) on CustomerID

I want to creat a measure that counts CustomerIDs from Table 1. I want to filter this on Table1 [colour] = "red"  and by Table 2 [product]="grocery" OR [product]="butchers". 

Measure to count items in table 1 but filtered across Table1 and Table2

My attemp is below but it ignores the filters I'm tring to establish on Table 2. 

Test2 = CALCULATE(COUNTA(Table1[CUSTOMERID]), FILTER('Table1',Customer[colour]="red"),'Table2'[product] IN {"grocery","butchers"})

I think I'm fundamentally missing somethng to would appreciate the help and guidence. 

Thank you. 

[some_bih]

Hi @TASylbaryn it could be you need RELATED

Test2 = CALCULATE(COUNTA(Table1[CUSTOMERID]), FILTER('Table1',Customer[colour]="red"),RELATED('Table2'[product]) IN {"grocery","butchers"})

I hope this is ok for you.

Check the link for example

https://dax.guide/related/