shawdow

I use a Canon A620 with there assigned housing. I come across this shadow sometimes:

Can someone explain this? Thank you in advance.

if your housing or dome port has any type of protection/feature which sticks out, this can block light from your strobes if they are placed to far behind or too low in relation. is this a possibility?

What housing do you use?

Sometimes a diffuser on the internal flash can helps.

To my eyes, this is clearly shading from port. You will need to zoom your lens in a bit to crop it out of the field of view.

If you look at the housing you can see exactly what is causing it:

Not the photographer's fault.

Alex

Is the housing design really that bad ?

I'd be interested to hear if zooming in a bit does avoid the shadow.

I used to get a similar shadow when my internal strobe would fire with my WA lens on so I would guess that is from your internal firing. The shadow is the lens port. My guess is you don't have an external strobe.