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I want to draw pixel art that should look like it is a scene from one of the LucasArts adventure games released around 1990-1995 (e.g., The Secret of Monkey Island and Monkey Island 2).

Most games were EGA or VGA-compatible, with 320x200 screen resolution, but pixels weren't square; pixel aspect ratio was 1:1.2, and hence my question:

Does it mean that I need to draw my art on 320x240 px canvas? Or maybe it will be more correct to use a different approach?

4 Answers 4

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This is an actual screenshot from the title screen of The Secret of Monkey Island (DOS, 1990):

Screenshot of the title screen of The Secret of Monkey Island (DOS, 1990), 320 x 200 px

As you can see (by downloading the image file and inspecting its properties), it's 320 × 200 pixels. As you can also see, it looks very tiny on a modern screen, and also slightly flattened vertically (although that's kind of hard to tell at a glance in this case).


This is what it would've (approximately) looked like on an actual VGA monitor in 1990:

Screenshot of the title screen of The Secret of Monkey Island (DOS, 1990), rescaled to 1600 x 1200 px

That's the same screenshot, but rescaled to 1600 × 1200 px. When viewing it inline here in this answer, your browser may rescale it back down to fit the Stack Exchange column width, but it should maintain the 4:3 aspect ratio.


Only that's not really historically accurate either, because this is more like what it would've really looked like on an actual CRT VGA monitor:

Screenshot of the title screen of The Secret of Monkey Island (DOS, 1990), rescaled to 1600 x 1200 px with a simulated CRT effect applied

This is the same rescaled image as above, but with some blur and a layer mask (generated using the "linear sinusoid" effect in GIMP) applied to simulate the scanlines and color mask of a CRT screen. Specifically, there are exactly 400 horizontal scanlines (because VGA used scan doubling in low resolution modes) at 3 px per scanline, plus a subtler pattern of 640 vertical lines to mimic the CRT color mask.

The difference is honestly kind of subtle, especially with the VGA scan doubling, but it does make the rescaled image look subtly nicer in several ways. Probably the most obvious difference is with the town lights on the bottom left, which now look nice and glowy instead of just a mess of blocky pixels. The text also looks smoother, the stars are less blocky and the dithering pattern in the sky gradient is less distracting. That's all because this is (closer to) how these VGA pixel graphics were originally meant to be viewed.

(The image with the simulated CRT effect also looks noticeably darker than the previous image, but that's not intentional, but just an unavoidable side effect of the applying the scanline mask. You can adjust you monitor brightness up to compensate for it.)


So, if you want to mimic the appearance of these 1990s VGA games, what should you do?

First, if you already have a high-resolution picture that you'd like to "convert to VGA", then I'd recommend:

  1. cropping it to a 4:3 aspect ratio,
  2. rescaling it (non-uniformly!) to 320 × 200 pixels, and
  3. if desired, quantizing it to a palette of 256 colors (with 6 bits per RGB color channel, if you really want full historical accuracy).

On the other hand, if you're manually drawing the art pixel by pixel (which is how these kinds of pictures would've historically been created, or at least given the finishing touches), then I'd recommend working directly on a 320 × 200 pixel canvas — preferably using a pixel art editor than can display the image rescaled to a 4:3 aspect ratio while you edit it.

Finally, if you want to show these pictures the way they would've looked on a 1990s VGA monitor, then I'd recommend doing something like what I demonstrated with the Monkey Island screenshot above (i.e. scale to e.g. 1600 × 1200 px and apply a simulated CRT effect). Or, alternatively, getting your hands on an actual CRT from the 1990s.

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    just want to say that scanlines were not really visible in the way that modern simulations/filters suggest.
    – Yorik
    Mar 28 at 17:36
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    @Yorik: They were maybe not as prominent as I made them out to be here, at least not usually, but you could totally see them (and other display imperfections, such as the RGB mask) if you looked closely at the screen. I grew up in the 80s/90s, I remember. At normal viewing distance your eyes would very quickly stop noticing them, though. Which honestly I think I got fairly close to — you could probably play the game on an emulator with my scanline effect applied, and after a minute or two you'd stop paying attention to the effect, since it's really just a superimposed static texture. Mar 28 at 22:04
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    There should be 400 scanlines in the image, not 200. Each line was emitted twice.
    – benrg
    Mar 29 at 2:14
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    @benrg: Huh, I didn't realize VGA used scan doubling in low-res modes. (I was more of an Amiga kid back then.) Thanks! I'll try to fix the image. Mar 29 at 8:12
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    Note that some media formats like PNG and Matroska have metadata to specify the pixel aspect ratio. (For example, pHYs.)
    – Nayuki
    Mar 29 at 19:49
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If you want your pixel art to closely resemble classic games from the EGA/VGA era you would have to draw it at 320x200 px in my opinion. Changing the height to 240 px would enable you to add more details than originally possible.

Then when displaying (or printing?) the pixel art you could consider scaling it to that 1:1.2 pixel ratio using nearest neighbor interpolation.

320x200 px images has the aspect ratio 16:10 but they were mostly displayed on 4:3 aspect ratio screens. To simulate that perfectly you have to find a resolution where the numbers add up. The smallest size you can draw a single pixel crisply on screen with 1:1.2 pixel ratio is 5x6 pixels.

So, if you want crisp pixels, the smallest size you can display a 320x200 px image with 1:1.2 pixel ratio at is 1600x1200 px. Next step would be 3200x2400 px.

I sometimes see 320x200 px pixel art scaled to 1920x1400 px. That would give you a pixel ratio of 6:7 ≈ 1:1.1667. Not quite right, but probably good enough if you need dimensions between 1600x1200 px and 3200x2400 px.

If crispness isn't an issue you could consider scaling to whatever end resolution you want using bicubic interpolation and perhaps some kind of CRT emulation. Emulators like DOSBox supports this.

You could also have a look at this answer I wrote on how to emulate a photo of a monitor.

Note that not all games of the EGA/VGA era were designed to be stretched to 4:3 aspect ratio. This article shows examples of both.

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  • Thank you so much. So I can use these 1600x1200 images for my own use, but what is the best way to downscale them back to 320x200 or maybe 320x240 (which one should I choose, by the way??) so that I can share them with other people on the web? I have found an amazing article which mentions few resampling and interpolation tricks, but I'm not sure they are applicable if we talk about downscaling and not upscaling.
    – jsx97
    Mar 28 at 0:42
  • Just a few tidbits. 320x200 has an aspect ratio of 16:10 (or 8:5), not 10:16. Non-square pixels were almost but not entirely ubiquitous during the EGA/VGA adventure game era. Lure of the Temptress comes to mind as a prominent exception. Here's a screenshot from the game that shows an example of incorrect aspect ratio correction: scummvm.org/data/screenshots/lure/lure/lure_dos_en_1_1_full.png Mar 28 at 0:46
  • @jsx97 320x200 is the resolution you should choose, but you need to work with 320x200 stretched to 4:3. i.e. A circle should look proportional at 4:3. A good workflow would be to start at 1600x1200 with a brush that's snapped to a 5x6 grid and use nearest-neighbour interpolation to scale the art down to 320x200. I think newer versions of Photoshop also have options to work with non-square pixels. How you export the art is up to you, but I would say 320x200, 320x240 and 1600x1200 are all valid options. Mar 28 at 0:57
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    @jsx97, I strongly recommend that you draw your pixels 1:1 in 320x200 px resolution. Otherwise you might make mistakes and shift pixels. Both Photoshop and Aseprite (which I recommend for pixel art) can display images with a custom pixel ratio. What you do after the design is ready is hard to say.
    – Wolff
    Mar 28 at 11:03
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    @jsx97, because I don't have Monkey Island screenshots... 😉
    – Wolff
    Mar 28 at 16:33
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To address directly your question at the end:

Does it mean that I need to draw my art on 320x240 px canvas? Or maybe it will be more correct to use a different approach?

The approach you take will depend on what type of art it is.

Note on output characteristics

Note all of the following information assumes that your final output resolution will be 320x200 because you are developing for VGA mode 13h (as used in DOS games). If you're developing for modern platforms, use square pixels instead as there is no technical reason to make life more difficult for yourself.

Pixel art

For pixel art you will need to create at 1:1, at 320x200. You just need to keep in mind in your head that everything will be stretched vertically a small amount.

Note that sometimes, original art would have been designed on the same platform it was targeting, so it may have been designed on a computer with the same pixel aspect ratio.

I don't know of any modern graphics editors that can deal with non-square pixels but your knowledge of eg Photoshop or other tools may be better than mine.

Suffice to say that creating the pixel at at 320x240 is not feasible because shrinking it to 320x200 is going to mess up the pixel effect.

Realistic painting or photorealistic rendering

Design using a 4:3 canvas with a much higher resolution, and only scale down to 320x200 on final output.

This will work perfectly well, it's just unlikely to replicate the kind of pixel art effect or at least hand-tuned effect of original games. Some original games did this, particularly after 1992. The VGA version of Monkey Island did this for close-ups of people's faces. The different to the main art style was noticeable.

Other considerations

If you want to recreate the kind of artwork in original games, keep in mind that in many cases the original games had artwork that was not designed for the correct pixel aspect ratio, and ended up stretched. This manifests in a number of different ways:

  • The Commodore Amiga (a similar platform to DOS on PC) had similar graphical capabilities but had a slighly different resolution and therefore pixel aspect ratio on PAL and NTSC displays, so many games may have been designed for one and ported to the other and the graphics merely stretched.

  • This is also the case for some Amiga games ported to DOS. A surprising number of popular DOS games from the early 90s were originally on Amiga. If the games were designed for Amiga on PAL systems then they would appear stretched on DOS.

  • A measure some people use of whether a game's graphics were designed for a different aspect ratio is whether circles are perfect circles or not. However, this fails to account for all the games where circles aren't perfect circles because the original designers themselves made that mistake. It can even be inconsistent within a game.

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    0 "The Commodore Amiga (a similar platform to DOS on PC) had similar graphical capabilities" - oh my. This is so wrong... The Amiga was way, way above the PC especially in her graphical capabilities, and the OS was way about MS DOS. It was not until SuperVGA that the PC world started to catch on. Mar 29 at 10:31
  • I'm not sure why we have our wires crossed on this but DOS VGA was ahead of Amiga in resolution and colors, DOS VGA had 320x200 at 256 colors and 640x480 at 16 colors, Amiga had 320x200 at only 32 colors and only 640x400 at 16 colors. Now as for acceleration of some 2d gaming features like sprites and scrolling, Amiga probably has a couple of advantages there. Mar 29 at 23:45
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    @thomasrutter Amiga had all sorts of tricks to improve its colourspace. HAM allowed 4096 colours for static images, SHAM/Dynamic allowed a different 16 colours for each scanline, and Halfbrite allowed 32 "bright" colours & another 32 "dim" versions of the same.
    – Adeptus
    Mar 30 at 1:01
  • @thomasrutter sorry if it came harsh or something, it was meant tongue-in-cheek-ly, but anyway, MS DOS being basically a single-tasking text-mode glorified CP/M adaptation was not in the same league as AmigaOS at all. And one could argue DOS had no graphical capabilities at all (the applications, being in complete charge of the hw had, and the adapter BIOS has some helper functions), whereas it was all built in into the Amiga. Mar 31 at 19:18
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Adjust your monitor resolution to have non-square pixels. Specifically, if you have a 3840x2400 display, set a custom resolution of 3840x2000. It will be 3840x1800 for a 3840x2160 one.

Make sure it stretches the image. Most programs will look a big ugly, though, but it works with no issues.

Then draw on a 320x200 canvas as you normally would. The stretched display will show you what exactly you're going to get on a 320x200 4:3 monitor, or in a game designed for such.

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