One way

Requires an array formula

- if entered correctly, the formula in the cell is automatically enclosed in { }

- but { } cannot be typed in

With "MyLookup" in cell

C1
Formula in

**D1**, confirmed with {CTRL}{SHIFT}{ENTER} and

*dragged down* to

**D10**
=IFERROR(ADDRESS(SMALL(IF(

$C$1=$A$1:$A$10, ROW($A$1:$A$10)-ROW($A$1)+1), ROW(A1)),1,4),"")

In

**D12**
=TEXTJOIN(",",TRUE,D1:D10)

TEXTJOIN is only available in some of the very latest versions of Excel

- not available in your version if formula returns

**#NAME?**
**Excel 2016 (Windows) 32 bit**
| A | B | C | D | E | F |
---|

**1**
| Image | | **Picture**
| A2 | {=IFERROR(ADDRESS(SMALL(IF($C$1=$A$1:$A$10, ROW($A$1:$A$10)-ROW($A$1)+1), ROW(A1)),1,4),"")} | |

**2**
| Picture | | | A5 | | |

**3**
| Likeness | | | A7 | | |

**4**
| Portrait | | | A10 | | |

**5**
| Picture | | | | | |

**6**
| Image | | | | | |

**7**
| Picture | | | | | |

**8**
| Likeness | | | | | |

**9**
| Portrait | | | | | |

**10**
| Picture | | | | | |

**11**
| | | | | | |

**12**
| | | | A2,A5,A7,A10 | =TEXTJOIN(",",TRUE,D1:D10) | |

**13**
| | | | | | |