As with lighting systems and camera equipment, backdrops require some kind of support to keep them in place. Background supports can be simple or sophisticated systems. The simple ones are easy to set up and break down and are well suited for location work, while sophisticated, permanent studio systems can hold multiple backgrounds that can be raised or lowered either manually or at the flip of a switch.
I would definitely play around with it. Your not going to want to go too wide with 4 because odds are they will move around a bit and you’ll end up with some soft faces. Some key things to remember would be try to keep their faces all on the same plane of focus, that will allow you to shoot a little wider. Generally with 4 kids I would aim to shoot around f/4 but certainly play around. At that aperture you may want to consider moving them further away from the background. Keep in mind the closer you are to them and the further away from the background they are the more bokeh you will get!
Anyone that does any kind of handy work around the house (or anywhere for that matter) definitely needs to keep a few of these on hand. They are simple. They are plastic, but they feel very strong. The spring inside is REALLY strong! It's got a tight grip for sure! I have around 40-50 of these (different brands) that I've acquired over the years doing woodworking projects. These rank right up there with the best ones! If you're gluing something, these are a must to clamp the parts together. Great grip and as inexpensive as you're going to find! (currently $9.99/1.67ea). Hard to argue with that!
Create the ideal setting for your photo shoots with photo backdrops and backdrop equipment. To accommodate a variety of client needs, consider stocking up on a selection of solid color and printed photo backdrops. Whether you own a collection of seamless background paper or you're just starting out in the business, you can choose from numerous designs and accessories suitable for headshots, family portraits, and product photography.