When to go
Best time
Morning, Mid-day, Late afternoon
You can visit the Bode Museum small dome hall, also known as the Klein Kuppelhalle, year round.
The best time to visit is in the morning on a weekday right after the museum opens so you can avoid the crowds of people.
You can also visit during midday or late afternoon for similar lighting conditions, but be aware that there are some small windows where the natural light comes in, so try not to visit on an overly sunny day. A cloudy day is best to balance out the harsh light.
Field tips
I recommend purchasing tickets online to avoid the lines: https://www.smb.museum/en/museums-institutions/bode-museum/home.html.
Play around with symmetry here, as the entire building is symmetrically laid out. You can walk through the hallways with statues on the left and right and experiment with different viewpoints that all create a uniformity within your shot.
You'll get some natural light coming from the side of the hall, which is interesting to play around with. If it's a sunny day, see if you can capture any shadows to create a sense of depth in your image.
Try out different angles, either from very high or very low. You can walk up the staircase and get a viewpoint as you look down onto the stairs, too.
Current weather
Do nearby
Check out the large dome (entry hall). You can pick up your tickets here, but even if you don't have tickets, the large dome is free to enter.
Walk around the rest of the museum and see what other unique areas you can find.
Visit the Neues Museum, which is another one of Museum Islands famed buildings.