This is pretty much equivalent to a technique I used to see people use in Photoshop. I think it's gone out of style recently, but used to be common (IIRC):

* Import a photo as a layer

* Duplicate that layer

* Increase saturation in that layer and then blur it

* Mix that layer by some percent (20-50?) over the base photo

Gives a nice ethereal feel.

You used to see this all the time in photos. But, maybe it's out of fashion now that everyone knows how to do it :/

When I recoded my canvas library's filters functionality last year (because: make it more like SVG filters, which allow you to branch the data multiple times, apply various effects, then merge them back into the final output - which is awesome!) I made a decision to include an 'opacity' attribute to each effect so at the end of the effect calculation it can be recombined with the input before outputting to the next effect. This was whimsy on my part, but it does make creating effects like this one quite easy - as can be seen in the Gaussian blur's test demo: https://scrawl-v8.rikweb.org.uk/demo/filters-001.html

I dislike seeing this effect, it reminds me too much of what I see when my glasses are dirty.

The old-school method to do this on purpose was a smear of Vaseline on a glass filter in front of the lens!

See also: Orton effect – https://en.wikipedia.org/wiki/Orton_(photography)

> and then merged them with mix-blend-mode.

In the demo, `mix-blend-mode: normal` is used. This is the default, so this line of CSS isn’t required. You can get some interesting effects if you do use one of the other blend modes with the blurred layer.

Usually known as [soft focus](https://en.wikipedia.org/wiki/Soft_focus). In lenses, caused by spherical aberration.

An old school way of creating this effect is to stretch a nylon stocking across the lens.

In Photoshop, I would…

1. Duplicate the layer, and in Curves or Levels, ensure that it’s average value is mid grey.

2. Set its blende mode to Overlay or Soft Light.

3. If result too strong, pull the left curve handle up and the right handle down. This will kill the contrast and softer the effect.

Similar process to this….

https://rmit.instructure.com/courses/87565/pages/photoshop-u...

For some reason all I can think of is Lady Galadriel

Another easy way to replicate this:

* duplicate your photo layer

* apply a Gaussian blur to the duplicate (5-10px, depending on total resolution)

* set the blend mode of the duplicate layer to "overlay"

* fiddle with the opacity to reduce the strength of the effect

The first image is how I see in real life (without glasses). The glow is not there of course, but the blur, yeah.

A smear of Vaseline on a glass filter in front of the lens was the old-school way to do this on purpose!

A bit off topic, but this remember me the effect used on the Coen brothers movie Inside Llewyn Davis, I love that movie, but the effect throw me off all the time and now is "the movie ruined with that effect" for me.

Ironically, the first image makes me think of a dreamy blur when it's in fact a dirty lens, but the author's image makes me think of a dirty lens when it's a calculated attempt at a blur.

Very similar to this effect

https://www.youtube.com/watch?v=SlUhr6ssc1U

Can the real smear be undone using a filter?

You can achieve quite the same effect by rubbing Vaseline on your lens. You can but don't.

Reminds me of how the early bloom effects looked like in video games

How is this different on halation, seen especially on vintage lenses?