Introduction

Redfall was developed on Unreal Engine 4 with DirectX 12 exclusively, which usually means that ray tracing is supported, but like with the recent Atomic Heart release, which was also built on Unreal Engine 4 with DirectX 12 and originally announced with ray tracing features, it was stripped out of Redfall and postponed into one of the future updates. This release on PC has support for NVIDIA's DLSS Super Resolution (DLSS 2.3), NVIDIA's DLSS Frame Generation (also known as DLSS 3), NVIDIA's Deep Learning Anti-Aliasing (DLAA), Intel's Xe Super Sampling 1.0 (XeSS 1.0) and AMD's FidelityFX Super Resolution 2.1 (FSR 2.1) from day one. In order to run this game at maximum graphics settings and reasonable framerates at native resolution, quite a powerful GPU is required, which is why upscaling solutions are so important. But depending on the game, there are subtle differences in the implementation of NVIDIA's DLSS Super Resolution (DLSS 2.3), NVIDIA's DLSS Frame Generation (also known as DLSS 3), NVIDIA's Deep Learning Anti-Aliasing (DLAA), Intel's Xe Super Sampling 1.0 (XeSS 1.0) and AMD's FidelityFX Super Resolution 2.1 (FSR 2.1), so we are keen to have a look at these temporal upscalers in this game.



Below, you will find comparison screenshots at 4K, 1440p, 1080p, and in different DLSS, XeSS and FSR 2.1 quality modes; the TAA, DLAA and DLSS Frame Generation screenshots are also available in the dropdown menu. For those who want to see how DLSS Super Resolution, DLSS Frame Generation and FSR 2.1 perform in motion, watch our side-by-side comparison video. The video can help uncover issues like shimmering or temporal instability, which are not visible in the screenshots.

All tests were made using a GeForce RTX 4080 GPU at Epic graphics settings; motion blur and depth of field were disabled for better image viewing. DLSS Super Resolution in this game shipped with version 2.3.1 and DLSS Frame Generation shipped with version 3.1.1.

Screenshots

Side-by-Side Comparison Video

Conclusion

In Redfall, the in-game TAA solution and XeSS do not use any sharpening filter in the render path and it's not possible to enable sharpening using a separate slider. However, the DLAA, DLSS 2.3 and FSR 2.1 implementations are using a sharpening filter in the render path, but only the FSR 2.1 implementation has the ability to tweak the sharpening value through a slider, which by default it is set to zero. Even when it is set to the 0 value, some level of sharpening is still applied in the FSR 2.1 render path. The level of sharpening in the DLAA and DLSS image is set to some high value by the developers and the image can look oversharpened at lower resolutions. Also, these sharpening filters in the DLAA and DLSS render path can cause negative side effects in this specific game, such as excessive shimmering in motion on thin objects and we recommend to manually update the DLSS version to 3.1 to avoid these issues.

XeSS comes with three upscaling kernels that are optimized for various architectures. The first is the kernel that gets used on Intel Arc GPUs with XMX engines. This is the most advanced model too, that not only performs better in terms of FPS, but also offers the best upscaling quality, Intel calls this "Advanced XeSS upscaling model." Intel also provides an optimized kernel for Intel Integrated Graphics, and another compatibility kernel, used for all other architectures that support Shader Model 6.4, e.g. all recent AMD and NVIDIA cards. These use the "Standard XeSS upscaling model," which is somewhat simpler, with lower performance and quality compared to what you get on Arc GPUs (we use the compatibility model on our RTX 4080). If DP4a instructions aren't available, as on the Radeon RX 5700 XT, slower INT24 instructions are used instead.

The in-game TAA solution has a very blurry overall image across all resolutions, even at 4K, and very poor rendering of small object-detail—thin steel objects and power lines, tree leaves, and vegetation in general. Also, the in-game TAA solution has shimmering issues on the whole image, even when standing still, and it is especially visible at lower resolutions like 1080p, for example. All of these issues with the in-game TAA solution were resolved as soon as DLAA, DLSS or XeSS were enabled, due to better quality of their built-in anti-aliasing solution. Also, the sharpening filters in the DLAA and DLSS render path helped. With DLSS you can expect an improved level of detail rendered in vegetation and tree leaves in comparison to the in-game TAA solution, and small details in the distance, such as wires or thin steel objects, are rendered more correctly and completely in all Quality modes. With DLAA enabled, the overall image quality improvement goes even further, rendering additional details compared to the in-game TAA solution and DLSS. However, DLSS has some issues that the in-game TAA solution does not. At lower resolutions such as 1080p and 1440p for example, the DLSS implementation has ghosting when flying birds are in the player's view and during evening or night time these birds even have black smearing behind them, which can be quite distracting. However, these ghosting issues can be fixed if you manually update the DLSS version to 3.1 instead of version 2.3, which is used by this game natively.

Speaking of FSR 2.1 image quality, there are a few important issues of note. In Redfall, sometimes the trees are in motion due to dynamic winds and other weather effects. The in-game TAA solution, DLAA, DLSS and XeSS implementations are handling moving trees and vegetation just fine, but the FSR 2.1 implementation is completely different. FSR 2.1 temporal stability completely falls apart when moving trees are in the player's view, as if motion blur effects were enabled at the highest value, which even our screenshots reveal, and it is visible even when standing still across all resolutions and quality modes. Thin steel objects, wires and power lines are also losing temporal stability at medium and far distances and create noticeable shimmering issues or disappear completely at lower resolutions.

The NVIDIA DLSS Frame Generation implementation is excellent in this game, the overall image quality is quite impressive. Even small flying particle effects, such as different varieties of the player's magic abilities, are rendered correctly, even during fast movement. Many other DLSS Frame Generation games that we've tested had issues with the in-game on-screen UI, which had a very jittery look—the DLSS Frame Generation implementation in Redfall does not have this issue. Also, the DLSS Frame Generation implementation in this game does not force you to enable DLSS Super Resolution first in order to utilize DLSS Frame Generation, as some other Unreal Engine 4 games do, and you can use DLAA and DLSS Frame Generation without any issues if you want to maximize your image quality.

Speaking of performance, Redfall is a very CPU intensive game, as the CPU usage is mostly single-threaded on PC due to a very poor implementation of Unreal Engine 4 DirectX 12. Especially high-powered GPUs such as the GeForce RTX 4080 can end up CPU bottlenecked in some sequences of the game, even at 4K. We've seen these issues before in other recent Unreal Engine 4 games, such as Star Wars Jedi: Survivor, Hogwarts Legacy or Gotham Knights. In such a CPU limited scenario, a very welcome help comes from the DLSS Frame Generation technology, which has the ability to bypass CPU limitations and increase the framerate. With DLSS Super Resolution in Quality mode and DLSS Frame Generation enabled, you can expect more than doubled performance at 1440p, and during our testing, overall gameplay felt very smooth and responsive, we haven't spotted any issues with the input latency.