Product Renders

I had a question the other day and thought I could maybe find some answers here. I have been working on improving my rendering abilities (mainly using keyshot). And I noticed a common thing people who are very good at rendering have been doing a lot recently. It looks like a lot of people are adding noise in post production to their otherwise photorealistic renders. I am just curious as to why this is because I have been trying to improve my rendering and I am trying to avoid noise as much as possible.

Is it just because it makes a cool looking image or what?

Please show some examples of what you mean.

Here are two examples. It just seems like it is a film filter on top.

Image Source


Using that amount of noise in any professional design studio is unacceptable, unless the effect is very strikingly done.

It gives an illustrative effect which is nice for internal presentations to other designers or artists, but clients actually want to see popping renders that communicate well, not so much artistic ones.

In some occasions, say vehicle renders, you can use a film grain.

Sometimes a computer render looks very CG-like because in reality the brain receives a higher variation in lighting details.
For example, renders often either look cold or warm while in reality there is always a balance.
What you can do to increase the perceived information is add a slight noise. What I do is 1% noise and then increase the highlight levels overall (from 255 to 242) so the background remains a pure white.

I appreciate the reply and the insight!

I figured it would be unacceptable for clients to see, I just wanted to make sure I wasn’t missing a trend in rendering now a days or something like that.

I will definitely try the adding 1% noise and increasing the highlight levels in my future renders.

Some rendering engines are inherently noisy without a long amount of time to process or high enough raytracing settings. Some of it could be post processing for effect, a little noise can add some film grain that makes a perfect render look more natural.

Looks more like a render that wasn’t done yet to me. If you render directly in Fusion 360, and set it to render on screen it will be grainy like this until the render is complete.

Here’s an example of render that look like the noise was intentionally added. Or it could have been only been added to the background to better match the textured plastic? Regardless, I’ve seen this trend more and more over the past couple years, especially in portfolios of newer designers.



I realize that renders a lot of time are noisy if the render isn’t given enough time to process. I was bringing this up more in the context that Lowe was saying

I have just noticed this trend happening a lot recently and was wondering if there was a reason for it.

In the lamp example it looks like it is intentionally done in post processing (photoshop) to take off the too-polished look renders can have.
As has been mentioned above it is not something that would be sent to or shown to clients.

In this field you have designing for the real world (i.e. clients and business) and designing for designers. They are two very different things.

The reason is many renders look too perfect, so adding noise is an easy way of introducing some more realism. Same as adding bokeh using a camera blur, etc.

I just did a quick render of a chair I designed a while ago to see the difference between adding noise vs. no noise. I can totally see how it gets rid of the “too polished” look of the render and sort of helps to hide the crimes of some small mistakes.


The “too perfect” effect often comes from a combination of a few things that include unrealistic lighting or shadows, shaders that lack the depth and complexity of real-world materials, and surfaces that lack fine detail. Noise can be used to alleviate some of these because it has the ability to simultaneously obscure poorly rendered details (e.g. bad fillets or edges) and add missing detail (e.g. material texture.) It can also give a feeling of reality as we tend to associate noise with the film grain present in actual photography.

When used solely as an attempt to elevate what would otherwise be a mediocre rendering, though, it becomes a crutch just like using an Instagram filter to elevate a mediocre photo. Really dig into your materials, lighting, and geometry, and you’ll eventually find that a noisy rendering will generally look inferior to something more polished.

Lots of CG artists have been doing this for a while. I see two main reasons for it.

First is a purely stylistic choice. Just like some inspirational sketches are highly gestural or try to create a mood, grudging up a rendring can change the perception of it. Hey even photographers apply these kinds of filters to photos. It can also help with work in progress renders from looking like finished products and leaves them a bit more open for interpretation. I’m on the fence about it, it feels more like a trend than an actually useful trick. There are other ways of making renders not look like finished products like blending in line work from the CAD model.


The second reason is photorealism. If you want to look photo real, you’ll need to simulate the camera at a certain point. This is where masters tastefully apply very gentle filtering to simulate grain, lens blur, lens flare, chromatic aberation, depth of field,… In this case you’ll see much more refrain in the use. Noise can also be really great when making composites with real images. First to match the grain in the original image but applying treatment to the overall composite often helps tie the different parts together.

Dropping mats on and rendering something out then adding noise is much faster than properly setting up scenes, lighting, mats, etc. though. For something quick and dirty it is probably more appropriate to do the first.

Yeah, I have noticed that to but I am not really a fan of doing this on the whole render like a filter.
It just looks to stylized for my taste but it depends on the purpose, object and story and there are definitely instances when it can be effective.
There are for sure lots of render cliches out there now but I guess these are just trends and they come and go.

What I have done a bit is to add noise to specific parts of the object to give it a bit more life.
Sometimes on fabrics for example to give them some more depth.
What I on the other hand use almost always is just a little bit of the high pass filter in PS.

But in the end no amount of post will save a crappy design so in the end, it all comes down to that :wink:

Agreed, it can be helpful on certain aspects, but I don’t really like the look of it on the whole image. Utilizing clown paths and noise however can be a great tool.

Funny. I did an in screen render real quick of something for a client today and it was grainy just like that. I wonder if it is a case of it becoming a style to look like quick renders? I’ll try to render up an old file tomorrow so you can see what I mean.

When used solely as an attempt to elevate what would otherwise be a mediocre rendering, though, it becomes a crutch just like using an Instagram filter to elevate a mediocre photo. Really dig into your materials, lighting, and geometry, and you’ll eventually find that a noisy rendering will generally look inferior to something more polished.

Exactly. Also a great point on photorealism vs realism, Louis.

The comparison of noise vs. no noise is a good example, you can see it adds a more realistic and warmer touch.
For a better effect, use slightly less (-0.25/0.5%) noise and whiten the background more so it becomes cleaner.

The best thing to do instead of noise is making materials more realistic with a slight bump and specular texture especially on wood and an added opacity texture for fabrics. Then what I do sometimes, a little Spielbergian, is adding a warm light panel on the side where light hits from the top, and a blue/purple one where the drop shadow is. See an example of my recent project here: Comodo Visualisation | IDZone
I find these colored side fill lights very effective. You can also spot the 1% noise here!

However for quick and dirty concept renders that have to be done in a few hours, including the CAD work, only adding that bit of noise is a way to improve workflow.

I see that photoshop added a grain slider in the camera raw filter BTW
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