Modern cameras nail focus. They are getting technically close to perfection. But the resulting images are sharp, very sharp. Maybe even too sharp to convey an organic and familiar feeling. I'd call it Human Warmth. Some photographers decided to go back to shooting on film to convey a warmer and more pleasing look. As this is not an option for me, I decided to try out diffusion filters.
What is diffusion?
Imagine a triangle of diffusion, halation and contrast. Every diffusion filter is somewhere inside that triangle. Some are all about diffusion (create softer images), some are all about halation (create glowing highlights) and some are all about contrast (basically reduce contrast). Most diffusion filters are a combination of these three aspects, all without overly reducing sharpness (which was important to me).
Diffusion filters work for still images as well as for filming video clips. Today’s lenses produce a clearly digital look. Diffusion filters can offer a subtle way to reduce that artificial feel. The most common use for these filters is to capture a dreamy, almost cinematic look which characteristics include blooming highlights and decreased contrast. Without you doing anything to the image in post.
Of course can add haze or dehaze a photo in post, but I always try to achieve the desired look in camera already. We all know, "Fix it in post" is a phrase uttered by photographers who screw up a shot.
The best effect that you can apply to a picture is the one you don't see but feel.
It takes a bit of courage to use a diffusion filter in a commercial production. At least I think so. But of course that depends on the client and how confident you are with the look you create. As you are locked into the look and cannot crazily go on and off with it in a photo series or film, I would suggest to go with a light touch when using a diffusion filter.
I bought all my filters for the Sony/Zeiss Sonnar FE 55 mm F/1.8 which is my standard lens when shooting a photo series. Most of the filters I bought came from Tiffen, but this is not a sponsored article.
Other similar filters have been introduced lately, too. For example the CineBloom by Moment. As I already bought the Tiffen ones, I did not want to spend more money on even more filters.
And in the end, I even decided to make my own filter. You can find the results at the bottom of this page.
Pro Tip
If you are more clever than me, you buy the filter according to the largest filter diameter of your lenses and then additional buy a set of step-up-rings. Then you can use the filter on every lens you own. This came to my mind when it already was too late.
No filter
For a better comparison I took some images without any filters on the lens. So, this is the basic look you get when photographing against the light (for a more flattering look) or basically with the light (or sunshine from the side to be exact).
A big thanks to beautiful Nathalie for making these test shots with me! All sample shots you can find below are un-retouched and basically out of cam to demonstrate the filter effects.



Tiffen Gold Diffusion FX 5
I am starting with a massive diffusion. With a density of 5, this Tiffen filter provides the greatest amount of softening.
The Tiffen Gold Diffusion FX 5 filter creates an almost soft focus-like effect, spreading the light to create an airy glow with added gold hues to warm your image and balance skin tones. Have a look at the highlights in the hair to see this effect.
Clarity and detail is retained, but skin is flattered and illumination is spread around highlights. Contrast is reduced dramatically when shooting against the light.




Tiffen Digital Diffusion FX 2
This filter is meant to appear invisible and is also known as the invisible diffusion filter. Compared to other filters it produces softness and diffusion with almost zero flare or contrast reduction. It helps to lessen facial blemishes, wrinkles, and gently smooth textured backgrounds while maintaining sharp focus. The density of 2 is considured to be a medium density.
Somehow it did not feel invisible to me. Shooting straight against the harsh sunlight, the background kind of turned blueish and felt very digital to me. The degree of diffusion at FX 2 is also a bit too much, if you ask me. The face appears almost as softly as in an 80s blue movie.
Conclusion: FX 2 feels too much.



But maybe a little less diffusion?

Tiffen Warm Black Pro Mist 1/2
This filter is a combination of diffusion with an 812 warming filter (used for improving skin tones). It helps to reduce the value of the highlights while slightly lowering the overall contrast. It is also useful for smoothing out and wrinkles and blemishes. The 1/2 density provides a small amount of contrast and highlight reduction and allows for a soft, pastel-like quality of light.
Shot from the right angle, skin colors pop and feel good. Almost as if the photo had been retouched already. It looks great, straight out of cam.


Tiffen Black Pro Mist 1/8
The Black Pro Mist 1/8 Filter helps to reduce the value of the highlights while slightly lowering the overall contrast. The 1/8 density is the most sublte density available by Tiffen and provides less contrast and highlight reduction than the other options while still allowing for a soft, pastel-like quality of light.
For me, this could be an always on filter, because the effect is subtle yet feels great. It's a cinematic look, right?




I think we have a winner


Wait, there's more…
There are other filter effects available. How about one that tweaks highlights and flare as well? For a cheesy 70s light sparkle effect, why not give a star filter a try?
HOYA Star Six
Star filters give a beautiful and romantic effect on bright parts of an image. Light rays differ with the angle towards the light, leading to a six lines cross pattern of light beams. This look can be cheesy but desired in erotic photography as a 70s reference.




DIY diffusion filter
Basic UV filter with golden spray paint
This homemade filter is the cheapest option for creating diffusion. You take a standard UV filter (25 €) and buy a spray can of gold color (8 €). You spray a touch of color on the filter and wipe it off using white spirit.
Some people use grease or vaseline instead of a spray can, but I don't like such materials around my camera. In the end it's a valuable tool and I always take good care. Call me uncool, but I always put lens caps on, etc.
These DIY filter results aren't too bad, right?




Please avoid tilting when screwing filters on
I recently made the mistake of screwing two filters on top of another. This is technically possible, but of course unnecessary. And when things go very stupid, like in my case, the filters jam and can no longer be removed.
Fortunately, I was able to remove them from the lens. But then the fun was over. They were just stuck. No matter how much force I used, no matter with which tool, they didn't move a bit. I used dish soap, creeping oil, hot water and a screw clamp. The two filters stayed tilted.
After one hour of trying it out, I finally put them in the freezer and was finally able to split them up a few hours later. Please make sure that the thread is only screwed in straight, always.