The Illustrator flare tool works well with a background, so firstly create a black background / rectangle etc or something to work with though you can use it with a solid white background. Apply the initial design by clicking on the art board and drag outwards to define the center and click the art board again to create the rings
The flare tool can be found in the toolbox beneath the rectangle (rounded rectangle etc).
It is a slightly odd feature in that it is a two parter. You can just apply the first effect and totally ignore the rings by changing to another such as the gradient or the rectangle etc. Though, if you subsequently go back to it, the second pass will still be active and the rings will appear (it is a live effect)
It should be remembered that the effect is a live effect and most parts of the design can be modified via the options dialog. If you have created two or more designs, you can always select it and modify only that as it is live. Just click on the parts of the design you want to change and move the origin point etc of the rings or center etc
You can interactively modify the generated art by using some of modifier keys such as UP / DOWN (number of rays). CTRL (size) SHIFT (constrains) and ALT (rotate). The modifiers are interesting and interactive but offer nothing that cannot be achieved via the dialog and the dialog does offer precision to the settings.
To see the options, double click the icon. There are a number of settings : center, halo, rays, rings. They can generally used independently so you can deselect the rays, rings etc and just use the halo etc. You can also set the numbers to low as well as high values for the rays etc to create a range of different artworks.
It generates a path and as a standard path it can be applied with a set blending mode such as normal or lighten. You can create multiple artworks all with different blending modes as well as different opacity settings. To change the opacity and blending mode, just click on the opacity link on the top control bar. Many different color effect combinations can be created by using different blends which can also be in turn, blended with a background
You can create an interesting halo by deselecting the rays and rings. Set the opacity etc high as well as the growth etc to high values. Set the brightness to the high or perhaps to very low, 0%. The fuzziness settings is an odd one, I am certain it does something (probably more path related and perhaps comes into its own if used with other paths). Duplicate the halo (alt / option) and reduce in size by scaling say to 75% of the original (you can do this via the center option as well). Align both. Repeat duplicate and scale again by another 75% etc. Great for creating a quick contour / halo effects. You can also shift the individual artworks and perhaps fill an entire image with the halos or perhaps align the halos in a line or perhaps create a circle of halos and more. Of course, you could just use two halos with opacity set to 100% and fuzziness to 100% and create two car headlights heading towards the screen.
If you don't want any rays applied, double click the icon. Deselect the rays check box. You can also set the number of rays to 0 even if the check box is on. The maximum number of rays is 50 - you can't enter 100 or more into the rays field (sadly). But personally, I like the rays so I generally keep the rays settings ON. The rays are very fine. The rays can be lengthened from 0 (again, no rays are seen) to 1000% of the size. There has to be said, little difference in the lines when the fuzziness is changed. All very subtle. Again, the rays come into their own when you re-apply a design over and over. If you create multiple artworks then you can generate more than the 50 ray lines. Four generated paths result in 200 lines filling the entire screen (if you use the maximum rays). I am certain there is some overlap so perhaps not all 200 lines can be seen but it creates a far more dramatic design than a single applied artwork. You can also use the alignment and rotate the path as you would with any standard path.
To apply this effect in a more repeatable way is by using the appearance panel and live effects - the transform command can generate more copies of the live effect (halo, rays and all) and rotate them as well as add additional transforms. You can add all kinds of live effects such as 3D, bevels, etc to the artwork and they can all be manipulated via the appearance panel.
It can be edited via the isolation mode (as symbols etc). Double click on any of the generated artworks and you will be offered different layers to edit such as core gradient which can be modified such as changing the highlight of the center gradient - though not, it appears, any color. You can position the core of the flare using the gradient (in isolation mode) as well as shrink the core or increase the size - you can also make the core more intense and sharper as well as a lot fuzzier - none of these options are available via the dialog. In isolation mode, you can also distort many of the paths using the direct selection such as the rings (individually)
They can be masked using a clipping mask. Generate the design. create a circle or other path. object menu clipping mask command to clip the range of the artwork. These paths are now filled with a dramatic burst.
Small artwork, ones created by clicking on the art board and moving the cursor only slightly before releasing, make for a wonderful sparkly background. Large artwork can fill an entire background in seconds where the length of the design extends beyond the document.
Create the artwork. Drag to the CC library. Go to Photoshop. Drag from the CC library into a Photoshop document. Apply effects to the new design. The result can be pasted into Photoshop (for some reason as a pixel option seems to work better than the smart object) and re-pasted or duplicates of the layer can be created. The colorful halos and rays are now just normal objects in Adobe ® Photoshop ®, you can apply layer effects such as metal and wood effects as well as live effects to the design such as blurs and oil paint etc. It can be added as a dramatic effect to text objects or shape layers in Adobe ® Photoshop ® Of course, there are also many powerful effects such as Gaussian blur which can be added to the artwork. You can also export the results to other applications such as Affinity Photo.
You can manipulate the artwork with live effects. The design needs to be selected.. Go to the effect menu and distort and transform and transform. The transform dialog will appear. you can then create multiple copies of the artwork (though note, they are all the same underlying design) by entering a value other than zero in the copies field at the bottom. You might like to leave the preview off but if you have a fast machine then you can just put the preview on and play with the rotate, scale, move etc options. Change the move and scale (you can set to greater or less than 100% and you can also have different scales for the vertical and horizontal) as well as the rotation. One thing to remember, if you are filling a circle - 360 degrees, 10 copies.. you really should enter 9 in the copies field as you already have one copy, the original.
Hold down the alt / option key and the reset will appear and click that to put the settings back to the default.
They can be saved as symbols by dragging the design into the symbols panel. You can then instantly drag it back to the art board or use it with the symbol sprayer as well as the ability to change the color, change the size, rotate the design and much more
The dialog offers no means to change the color of the artwork, so applying the effect results in the same color effect each and every time (whether large or small). You can change the color by going to the edit menu and the edit colors menu and select the recolor artwork. Use the various color settings to change the color. You can also add a new color to the design via the appearance panel by adding a new fill or more than one fill. You can use the edit menu edit color and color balance command to turn the artwork into a red or blue design.
The rings option adds an extra touch of class to the artwork. The rings do not need to be applied in a particular direction, they can be just layered on top of the center of the effect. just set the path to 0pt. The number can also be set to 0 which is the equivalent of deselecting the rings option. The maximum size of the rings can be set by the largest option - you can have small rings as well as super large rings all relative to the actual artwork. You can also create multiple paths and combine them with blending modes etc to create stunning ring effects.
Ultimately, the effect is made up of multiple paths (open and closed) and you can just ungroup the design. Ungroup and the artwork is no longer a live effect and can no longer be edited. The design can be broken into rings, rays etc. You can then modify each part such as adding additional designs to the artwork or moving the origin of the rays and more.
You can, if you wish, rasterize the artwork via the object rasterize command and then you can apply a live image tracing to the design. You can then create a colorful trace or just a black and white trace. An alternative to this, pass the design to Photoshop and apply various image adjustments and then re-copy the design back into AI and then apply the image trace. You can see the result of an image trace applied in black and white
I am not so keen on a singular burst as I always feel the effect really comes alive if you are willing to throw all caution to the wind and apply multiple bursts to a design and multiple applications that are applied with different blends. Millions of truly wow graphics can be created using multiple applies such as sparkly to starbursts to subtle blurry fog scenes and more.
By just changing the opacity of the artworks or blending modes, you can turn bright headlights into a misty badly lit scene - which would look even more misty if there was something blended into the background of the artwork. You can the opacity via the properties as well as via the control bar.