Scaling Cave Story to 4K with the RetroTink 4K

I recently got my hands on a Retrotink 4K. For those of you who don't know, Retrotinks are devices that allow you to plug in retro video game systems and have them look pretty on your modern TV. The Retrotink 4K is the fanciest one, scaling retro consoles to 4K, along with having super fancy CRT scanline effects. For example, here's the Genesis/Mega Drive version of Cave Story with the consumer CRT filter:

(Note: For all images with scanlines, my capture card made them super dark so I had to manually adjust the colors to look normal. If any of the colors look a bit off, that's my bad)

The other big feature with the Retrotink 4K is the HDMI input. It might seem weird for a retro scaler to have an HDMI input, but it actually is useful. Not only can it be used to scale 1080p to 4K, it can also add scanlines and CRT effects to games with pixel graphics. This is through a feature called pre-scaling. To pre scale an image, you go to the "Scaling/Crop" menu and adjust the vertical pre scale based on the resolution. For example, for a 240p game being output at 720p, you would choose the 1/3 pre scale, and then you can add the scanlines!

The first game I wanted to try pre-scaling with was the CS+ Switch port. Cave Story is a 240p game, so a 1/3 pre scale with the Switch set to 720p should work, but it didn't. I then tried all options at 1080p, but none of those worked either. I then tried my last resort: 480p mode, which most switch games aren't optimized for. Thankfully, the vertical lines lined up perfectly, but everything on the horizontal axis doesn't look quite right:
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Using fancier CRT effects and using the "Horizontal Blur" function does help mask the problem:


With these setting, CS+ on switch can look OK, but these aren't the results I was hoping for. Before we move on from the Switch, there is one other Pixel game I want to talk about: Kero Blaster!

Not to start a Playism vs Nicalis debate, but Kero Blaster on Switch is actually much better visuals-wise than Cave Story on Switch. When put up to a 4K lens, Cave Story is slightly blurry, while Kero Blaster is razor sharp, even with no pre scaling! If you want to get those scanlines though, then set your Switch to 1080p and the pre scale to 1/8.


You can even set the horizontal decimation to 8 input 1 output to use some LCD effects! Do note that story text is hard to read using scanlines, and impossible to read using LCD effects.


After that I wanted to get Cave Story scaled properly. And I want to try to scale the original PC version. To do that, I'll be using a Steam Deck with a Dock. You probably can do this with a regular PC, but the Steam Deck was easiest for me. First, you need to go to desktop mode, download Cave Story add doukutsu.exe as a non-steam game, go to it's steam properties, allow the use of an external tool, then choose any version of Proton. Then, in gaming mode, configure your controller so that it matches with Cave Story's key binds. Go to the Steam Deck's display settings and set the resolution to "640x480@60" Doing that makes sure that the Retrotink is doing all of the scaling. Then, run Cave Story and it should be running with super sharp pixels. Set the pre scale to 1/2 for some scanlines:

Sorry, the screenshot didn't look right so I had to take an off-TV picture. This meathod of setting the Steam Deck's resolution to 640x480 should work for any 480p game, including Ikachan. Text is slightly affected but still readable. This method also works for Cave Story+ on PC:

Thankfully, with Cave Story+, all text is perfectly readable

Since the Switch version wasn't that great with the pre-scale, I needed a new widescreen version, so I tried out Doukutsu-rs. It works perfectly with the Steam Deck set to 720p with a 1/3 pre scale. Things can get really interesting once we add in the lighting effects:


For completion's sake, I tried out Pink Hour (Which would be the same settings as Kero Blaster PC). Unlike the Switch version where you use 1080p, you want to set the Steam Deck to 720p. Then, set the game's display size to "Full Screen", and use a 1/4 pre scale. The game looks great this way!


Anyway, I hope you enjoyed this look at Cave Story with CRT effects at 4K. The Retrotink 4K is a really cool device, and the possibilities feel endless!

 

We should ask Pixel what monitor he was using to do the pixel art back then and fine tune the settings on one of these filters to make it look exactly like his monitor.

 

We should ask Pixel what monitor he was using to do the pixel art back then and fine tune the settings on one of these filters to make it look exactly like his monitor.

TBH I don't think some random 2000's Japanese PC monitor is the "real definitive true" way to play Cave Story. Considering it's 240p resolution and control scheme, it's obviously based on 16 bit games from the Super Nintendo/genesis. Those consoles would have been played on consumer CRTs (the look of which varies wildly between units). So I'd say there's no inaccurate way to add scanlines to Cave Story.

 

Given it's Japan, it's gotta be a Toshiba monitor. But yeah um, this looks very cool. I wonder how Ikachan looks...

 

I wonder how Ikachan looks...

I just tested Ikachan and the results are very cool!

Here is the Consumer Slot Mask preset:


Here is the Trinitron Preset:


And here is a PVM style preset:


These do make me appreciate how pretty of a game Ikachan is! The only thing to not is that Ikachan has you choose the settings upon startup. This means you have to either plug in a mouse or bind the mouse to something like an analog stick on a controller. Not hard to do but a bit annoying, and you have to make sure you choose the "Fullscreen" video option.

 

Triniton is kinda the best one here ngl. It looks awesome.

Edit: Alula did her thing

Pixel used a Dell Latitude E6420,
this is the panel according to her

https://www.panelook.com/LTN140AT16-201_Samsung_14.0_LCM_overview_13193.html

 

Edit: Alula did her thing
View attachment 9559
Pixel used a Dell Latitude E6420,
this is the panel according to her

https://www.panelook.com/LTN140AT16-201_Samsung_14.0_LCM_overview_13193.html

Wow that’s funny. Just goes to show that great creatives don’t always have the best hardware lol

 

Dude I made all those quote sprites for cave story multiplayer everyone likes using like a really badly tuned screen like I get it bro :sob:

 

nice