For my Canon 580exII and Yongnuo 560II speedlites I use the following gear to modify light.
I have one of these 43 inch convertible umbrellas and one that is 30 inch. They have a black detachable cover that is silver on the inside. So you can shoot through or bounce off of the inside of the umbrellas. I don’t think I’ll get a 30 inch again as the 43 provides more light spread i.e. more surface to hit with the output of the speedlite.
This Manfrotto umbrella clamp is the best because the hole to put the rod of the umbrella into is slanted which positions it properly in front of a speedlite.
I then have two of these inexpensive umbrella stands which I routinely use to mount and manipulate other gear. Their umbrella rod holder is drilled flat which causes the speedlite to aim more toward the edge of the umbrella than the center. You can solve this by the use of a mini ball head to help target the speedlight better.
Combine them with a Manfrotto clamp grip and you can stick a light or mic anywhere.
These all go on Cowboy Studio light stands which are not pro quality but will get the job done on a budget.
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