Using motion blur on your bokeh/light spots can create a really interesting effect. This is one I use somewhat often, depending on the size, amount, and spread of the bokeh.
In general, I find this works best if you have bokeh that:
- runs in lines, eg., between straight tree trunks, rather than in large clumps
- isn’t overly blown out
- is reasonably separated (eg., not large clumps of spots).
As with all these techniques, use with moderation. I find that most people, after they have learnt this technique, tend to go a bit overboard and suddenly have super stripey forests.
Personally, I prefer a more natural look to my forests, rather than these stripy lines… instead, I prefer to make my bokeh shimmer and melt. It makes them feel a bit more dreamy, without being overly fake.
But you can, of course, find your own way of working. Just remember what your intention is with your photo. I find the stripy backgrounds rather distracting, and I don’t tend to pay much attention to the subject. In my photos, I don’t want my audience to be distracted, or they’re likely to leave your photo.
Always ask yourself: is this edit going to help, or hinder my photo?
Some examples of where I’ve used this effect.
We have two ways we can apply Motion blur to our image, depending on what we’ve done to the image beforehand.
If we’ve done some copy/flip, Content Aware or similar we can either:
- simply apply it to a non-smart object image layer, like our smooshed layer that we’ve been using in earlier lessons (note: duplicate your smooshed layer first!!). We can then mask it in.
- The problem with this is that we can’t change the amount of blur, or remove it from the image. It’s applied to the pixels. As soon as we save and close Photoshop, or go further down the editing path, we will struggle to undo that effect if we change our minds. It is inflexible editing.
- The other option is to make a duplicate of your smooshed layer, click Filter > Convert for Smart Filters. This will make it a Smart Object of sorts.
- Now, when we apply the motion blur filter to the layer, it is applied as a Smart Filter which means we can turn it off, edit it, make it stronger or weaker, etc. It is flexible editing.
If you do not have other image layers/a smooshed layer & are still working with your original:
- make a new version of your smart object (Duplicate will work here, as if we go into Camera Raw Filter we want any changes to apply to the gaussian blur layer too)
- go to Filters> Motion Blur
- Choose how much you want it to blur, then click Apply
- Mask it in where you want it. Personally, I very gently brush it in on the bottom of the bokeh spots, and maybe slightly on the top.
Since you’re working on a Smart Object layer already, it will be applied as a Smart Filter, so the effect will be editable at any point.