DIY is a common method for creating gels for your speedlite. Buy some gels, cut them to the right size and find a way to mount them to your speedlite. I did this a couple of times before. But if you have to rely on your stuff then the DIY method is sometimes annoying. Because of this I was in the market to find some new gear which is rock solid and convenient. I decided to go for gels from the Honl Photo Professional Lighting System.
Mounting a gel to a speedlite is very easy. Honl offers a Velcro strap called Speed Strap. You simple wrap this around the flashgun. The gels have Velcro straps attached on two sides so you can attach them easily to your speedlite. See the pictures below for details.
You have to take care how you attach the gels. Always leave some space between the gel and the front of your flashgun. If you don't, the gel will melt and damage your speedlite. I learned it the hard way. I attached the gel below a grid which is a very bad idea in addtion to a full power pop. So again: Be careful.
For transportation of your filter collection you can buy the Filter Roll-up. For me this is a very useful addition to the gels. Currently I fit in there about 30 gels. Just roll it up and store it in your camera bag. Searching a gel is very convenient since all gels are labels on both sides. Getting one in or out is easy too. Before I got this bag I stored them bare in my camera bag and some of them are looking exactly like that.
Why to use gels?
There are two reasons to gel your flashgun. The first is to balance the color temperature of the ambient light and the light emitted by your flashgun. The second reason is for effects. You can create colored backgrounds or emphasize elements with a specific color.
Your camera can set the white balance to one value only. Modifying the color temperature of a flashgun becomes necessary if you shoot in mixed light condition. One light source is your flashgun. The other is usually the sun or artificial light. To adapt the output of your speedlite to the light temperature of the sun or bulbs you'll probably use some kind of orange gels. If you shoot with neon light you might want to change the color of you flash into the green direction. For aligning the flash color temperature to the ambient light Honl offers the Color Correction Kit. Especially I like the 1/4 CTO gel which I use very often.
Gels can be used for color effects in your pictures. Just mount the desired color in front of you flashgun and you're done. For color effects Honl offers three sets of gels:
Egg Yolk Yellow
To following section gives you a feeling of what you'll achieve if you use colored gels. I used two speelites. One for the foreground and one for the background. I took 15 different gels one time to change the foreground color and the second time to change background color. The second flashgun was bare. Just hover the images or click them so see which gel was used. By the way it was quit complicated to create the sample images. In addition to the pottery cat there was a real cat names Zoe around. Zoe tends to cuddle the pottery cat and moved it around. But as you can see finally I managed to get the images. Let's do not count the extra scratches...