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Seattle, WA, USA

Posted Wed Oct 18, 2017 6:26 pm

One of the original reasons I launched was over my frustration from seeing screenshots of gorgeous Amiga games being presented either in widescreen format on LCD monitors, or straight screen-captures taken from emulators at 320x200 (NTSC) or 320x256 (PAL) and left untouched.

And while those captures are indeed pixel perfect snapshots taken from Amiga technology - so called 1:1 pixel perfect - back in the day nobody ever saw the output screens this way. Not the designers of the games nor the gamers themselves ever saw a single game on their 4:3 CRT displays in a pure 320x200 format. So, I decided to start to create my own images of the games we all love in the correct aspect ratio we all remember. Is it a task I’ll ever come close to finishing? Hell no. But I’ll at least have fun pecking away at it each week.

Back in the 1980s and early 90s, Amiga owners - usually when they first bought their machine - were expected to reach behind their monitor and twist a few adjustment knobs to ensure their computer’s picture fit their CRT 4:3 screen, whether it be on a computer monitor or broadcast TV.

Therefore, a 320x200 NTSC image created by the Amiga was physically stretched vertically to approximately 320x240 - 20% taller vertically than the computer’s literal output. This made the images taller vertically up and down just ever so slightly yet it made a world of difference.

I wrote about this issue in great detail in 2016 not long after launching AmigaLove.
Proportional problems abound online. Exhibit A: Defender of the Crown

The entire topic is extremely convoluted and at times quite complicated (especially when you include the PAL/NTSC differences into the mix) but researching the issues were enough to help me educate myself about this pervasive problem around how history is being saved and presented to future generations. Shot97Retro created an excellent video on the subject; it is long but gets to most of the relevant nitty gritty for those interested in this problem.

There is also an incredible article on Gamasutra about the amazing differences between pure pixels and NTSC signal artifacts mixed with CRT distortion which is a whole other topic worth considering. For example, most of the indie retro games out there are created in a very pixelated fashion but aren’t displayed the same way as they were 30 years ago. So they look similar, but different.

And you know it’s bad when legendary Amiga artist Jim Sachs even laments about how everyone presents his games incorrectly online these days.

I became convinced of a few things early on:
  • To invest in CRTs. This ensured not only the correct aspect ratio for games and other software, but it also guaranteed the natural pixel dithering and color blending that can only be reliably created on a CRT monitor. Plus - everything looks perfect in-person. No harsh jaggies, no completely flat lifeless colors.
  • To take actual pictures of my screens with a camera for all game reviews, and not use screen-capture tools if possible. This is an extremely time intensive way to capture computer game visuals, and the results are not always pretty. But this dedication to the process does have many more pros than cons in my view. Most importantly it nearly guarantees that the game images presented are how they were viewed from a historical perspective, too - by those creating as well as consuming the content.
When I go to Moby Games or Lemon or Youtube (all sites I love and use regularly) - practically anywhere - and see very well-meaning, well-intentioned screenshots and videos of the games I love, they are almost always distorted and shown incorrectly. It's either because images are being captured straight from emulation and output without any adjustments made, or they are projected on a modern monitor that doesn't letter box its output correctly - or both issues combined. To that end, emulation more often than not only presents the 1:1 pixel outputs and doesn’t convert the output to 4:3, which is simply tragic. (Side note: It would be nice if Amiga Forever et all had a 4:3 aspect ratio "fixer" checkbox of some sort). And this issue isn't confined to the Amiga. It's a problem found across nearly all retro consoles and computers.
This image is not here to shame anyone, it is simply an example of a very common problem that the retro-gaming community is facing due to newer technology that is replacing aging hardware. And yet we all know this game was never meant to be stretched this wide. In a best case scenario, it would somehow be letter-boxed on the sides.

Frankly many folks just don’t have the old hardware anymore. I totally get that. But from a historical perspective what viewers are looking at is close but not entirely accurate. It's about 80% accurate. Everything is literally being squashed (or stretched), as if someone sat on all of the images and crushed their heights vertically by 20%. Once you start to see the issue you can’t un-see it. It’s everywhere. AmigaLove tries, in our tiny little way, to set some of the history right. If nothing else, awareness isn't a bad thing.

That being said…

Back in the day there were also needs by content creators to take images of their screens and put them into magazines and other print media. Imagine it is 1986. You don't have a digital camera - only film. You don't even have a way to preview a shot before taking a picture. If you do happen to have a camera and know how to use it with a CRT screen without capturing distortion, you then have to find a way to get that screen into print, which means you need (an Amiga) to digitize it.

It would have all been a very lengthy and costly process indeed.

Today, these kind of issues are barely an afterthought. Both Windows and Mac OSX have had built-in ways to capture entire screens, active screens or custom cropped screens right from the OS.

On Windows, one can press the Windows Key + Print Screen to capture an entire screen and automatically save the image in the Pictures > Screenshots folder. It’s not super fancy but it works, and there are free apps out there that give Windows users more creative control.

On Mac OSX there are really fantastic built-in screenshot tools which save captures to the desktop. One can either do entire screens by pressing Command + Shift + 3, or specific user-drawn regions by pressing Command + Shift + 4.

What about the Amiga?

The Amiga has no built-in screen capture software.

Back in 1986, a small software company called Discovery Software International (yes, the same people who brought us Arkanoid!) created a handy piece of software called GRABBiT. This utility comes on a single floppy disk and, supposedly when launched, only uses 10K of RAM. That’s pretty fantastic.
Front soft-cover of the GRABBiT manual and disk holder.

Inside front flap for GRABBiT with its handy hand-written serial number, just in case you need to call tech support.

Pretty cool little paper holder for the disk on the inside of the back flap.

GRABBiT can be easily installed to hard drives if you have one or used from a floppy drive. It requires that you use an Assign program, or command, so you can tell it where you want the screen grabs to go. You’re given the option to print the screens (literally, print to paper), or save them to a second floppy drive or any other kind of drive you have attached.
GRABBiT's disk and launcher icon is, well, kind of hilarious. But it works. I wish the click-state crushed the disk.

Since my machine has plenty of hard drive space I actually put the Assign statements in my S:Startup-Sequence file so they get loaded when I boot-up my machine. Then, I just launch GRABBiT whenever I want to use it.

So - what does GRABBiT do - and who cares!?

It allows you to "print or save any screen, from any program anytime!"

To be completely honest, it creates screen capture files that look exactly like what one might pull from an emulator - an exact 320x200 image for NTSC screens. It does have the ability to grab higher resolutions, too.
Some screenshots I captured using GRABBit when viewed within DOpus 4.

The files here are automatically named by GRABBiT. GI (grabbit) 4L (large resolution) and the numbers are added sequentially.

How to use GRABBiT:

Assign where the files should go. Either use the program on the floppy that will do this for you every time you want to capture some screen grabs, or edit your startup sequence.


To save your images to your main floppy drive:
Assign GRAB: DF0:

To save your images to your secondary floppy drive, in a folder you’ve created:
Assign GRAB: DF1:Pictures

To save your images to your RAM drive:
Assign GRAB: RAM:

To save to a folder on one of your hard drives:
Assign GRAM: DH1:Pictures

And so on.

After launching the program (if you aren’t executing it from your startup sequence) you invoke GRABBiT at any time using a series of keyboard commands, just like a modern OS.

Press all three of these at the same time:

CTRL ALT P (P)rint the front screen. Unless you’ve got a printer, this is useless.
CTRL ALT S (S) the front screen to disk <— what I do.
CTRL ALT N Brings the (N)ext screen to the front.
CTRL ALT C (C)ancel the GRABBiT Print operation. Good to know, just in case.

That’s it. Super simple.

The files it creates will be IFF files - an ancient file format created by Electronic Arts along with Commodore/Amiga back in 1985 - which amazingly Photoshop still supports.

I used GRABBiT to capture the intro screen of Starflight 2. Here is what that looks like verbatim without any editing.
Screengrab of Starflight II's intro screen using GRABBiT: 320x200.

You can see right off the bat that this image looks pretty good, but in reality it is being squashed vertically. The colors are deep and vibrant, but the CRT scaliness are missing as is the pixel dithering and, frankly, it is lacking in natural color glows. Still looks cool, though, I think we'll all agree.

But no one, not even the original designers, ever saw the artwork this way back in the day.

The circles are a bit chubby, but the truth is focusing on circles as proof is a fallacy. These designers used tools like Deluxe Paint, and what they saw on screen looked much more like the photo below. Look at the light bouncing off the crest of the blue planet the shiny reflections in the insect-like alien’s eyes…
This is an unedited photo taken of Starflight II on a 1080 Commodore monitor. It was designed to fill the screen as best as it could.

Now, you’ll also notice that the blue outline of the image does not go to the very edge of the monitor’s screen. There is about a 1.5 cm border of black - that is a natural fact of life for CRT monitors. Sometimes you could stretch them to fit, but the border is consistent all of the way around so the aspect ratio is correct and proportional to the monitor’s viewing pane. It's 4:3.

Here is the "1:1 pixel perfect" GRABBit capture and the photo, side by side.
Side-by-side comparison

One of the advantages of the screen capture is that you don’t get the glass curvature distortions. But again, this is exactly how the images were seen when they were created, so screen curvatures aren't a bad thing.

However, back in the day, print publications nine times out of ten would have preferred the straight, flat screen grabs when placed inside their print layouts. It would have given them straight lines, solid color fills and true blacks without any editing. The only thing some might want to have done was stretch the screens vertically to fit a 4:3 box.

I’ve almost always tried to make my images fit to 640x480 or somewhere very close to that. That is perfect 4:3. The truth is, mine usually have black borders around them, too, inside that rectangle and aren't always 100% perfect, but they are historically accurate representations to the best of my ability.

There are times when I simply can’t get a good picture of game. Either it’s too action packed and I get a ton of motion blur, or the colors on-screen are simply too high-contrast and too difficult to capture. For example, I had a heck of a time with Desert Strike’s color palette. Everything shifted in hue where yellows would become greens, etc.

GRABBiT is a good fall-back choice for me in cases like that now. If I can’t get a good shot, I’ll load GRABBiT and use its simple keyboard commands to save some pictures to my hard drive.

But I won’t stop there.

I’ll take the files into Photoshop and stretch them to fit a 4:3 aspect ratio. It’s just something that needs to happen. I’m not going to put some goofy scanline effect over the image, but I will ensure it isn’t presented in widescreen format.

So, the original 320x200 will get transformed into something like this in something like Photoshop:
An original screengrab of Starflight II for Amiga at 320x200, but converted to 4:3 in Photoshop.

How to convert GRABBiT's image files - and how to fix screen-grabs for any platforms that output 300x200

You need to move the file from your Amiga (or whatever) to your PC or Mac. I use Amiga Explorer and a null modem cable.

Before we go any further, I need to point out that it's simply fantastic that Adobe still supports Amiga's native IFF image format. Every now and then a big corp deserves a bit of praise for the things they get right.

Once you import your IFF image into Photoshop, when you change the image size you also then change the Resample algorithm to “Nearest neighbor (hard edges)”. This virtually guarantees you won’t get any pixel dithering when you resize things. To have the most flexibility, one should scale an 320x200 image to 1600x1200, then scale down to 640x480 or whatever size is desired. This is called the 5/6 method, which is explained beautifully here.

I can then create a Photoshop “Action” of my previous steps, which is an automated batch process I can run on an entire folder of images.
It's a pretty startling moment when you see your big pretty Amiga artwork relative to your current machine's resolution.

This won’t be my go-to way to grab all images going forward, but it’ll be my solid second choice for games I can’t seem to capture accurately. It’ll at least allow me to get closer than simply pulling a file out of the hardware or emulator and leaving it as-is, which isn’t right. It still doesn’t look as good as a CRT image, but at least it's aspect ration will be technically accurate. And to folks like Jim Sachs, that's a really big deal. That's good enough for me.

I’ve pulled the ADF for GRABBiT off my original disk, and I’m providing it here for download in case any of you want to play around with it, too. Just promise me if you use it you’ll stretch your images afterwards if you can! :)

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New Jersey, USA

Posted Mon Nov 13, 2017 7:24 am

I'm glad to see that you strive for that perfection here on the site; it's a true labor of love to show the games as people who both created them and played them back in the day, when CRT monitors were prevalent, as they were presented to us. I'd love to see more of this happening in other sites covering retro computing and retro gaming.

I did download the GRABBiT ADF and try it in FS-UAE, but keymapping of the emulator's functions of course butt heads with GRABBiT's own hotkey mapping, so I'll have to just leave it for physical hardware, methinks. (Plus side: I can at least use TrackSaver on AmigaOS 3.9 to write the ADF to a disk! :) )

Since I'm on Linux, I don't have Photoshop as a native graphic editor, but I do have GIMP, which I've become quite used to. But one problem: out of the box, GIMP doesn't offer native Amiga IFF file format support for import/export, but I did get ahold of this plugin which added that support for me. This is something I feel that the GIMP developers should merge into their main code branch and make a standard feature; native support for practically every file format under the sun would be a massive benefit. :)

But all things considered, this is a practice that should be taken more into account: more emulators should offer a proper 4:3 viewing option to present the art in the right way.

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Seattle, WA, USA

Posted Wed Aug 04, 2021 9:44 am

Recent screen pulled via Grabbit, as seen within Deluxe Paint III. :boing: <3

Sorry for the slight blurriness. Low-light long shutters are tough without a camera stand, which I didn't bother with.

(Splash screen taken from SSI Gold Box game Treasures of the Savage Frontier, 1992.)

I thought for a brief moment I could take this image and crop out a piece to create an icon for the game, which doesn't come with one. What I failed to remember was these images are 320x200 and icons used in a Workbench resolution are twice that vertical height, thus stretching the image to Hades. But I was still able to grab one of the tiny gray skulls and use that as a basic template, which was fun.

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Posted Wed Aug 04, 2021 3:06 pm

I took this as a challenge to create settings to show NTSC as accurately as possible using the Indivision AGA MK3, a device that sits on top of the Lisa chip and digitally reads the Amiga's native video output and turns it into an HDMI (or VGA) signal.

For this, I created my own HDMI resolution of 1424x864. The vertical resolution is easy enough: that's twice 432, which in turn is 80% of 1080p. I then applied the Amiga's 22:26 NTSC pixel aspect ratio and added some overscan to come up with 1424 HDMI pixels per line to show "860" Amiga pixels. It all gets a bit confusing...

I then captured the results with an HDMI capture device. First, DPaint, which in NTSC mode does indeed use non-square pixels:
Frontier, however, seems to be using square pixels so the circles look stretched. This is a significant issue when trying to address the NTSC pixel aspect ratio issue, as a good amount of software did act like the pixels were square.
And finally I displayed that Starflight screengrab and captured the HDMI output:
I find it absolutely necessary to use scanline emulation with 240p / 288p video on LCD monitors to hide the very low resolution a bit. (Which of course makes the image a bit darker.)

Despite also using some filtering, the output is still very sharp, with no visible blending of the pixels. But remember, this is lores, and multisync monitors we used during the AGA age were a good deal sharper than the monitors used with the OCS machines in the late 1980s, so I don't feel that's all that inauthentic.

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Posted Wed Aug 04, 2021 3:26 pm

Ok, the full screengrabs don't show the difference very well. Here's closeups of the Photoshopped grab, the photo and my Indivision HDMI grab, all resized to the same size.

Indivision HDMI:
Resized again:
BTW, I wrote for a computer magazine off and on in the 1990s, and it was a huge improvement to be able to send in screengrabs rather than having to take photos. Lowly writers such as myself wouldn't scan photos, but just send those in analog through the mail.

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Posted Thu Aug 05, 2021 1:31 am

Oh, and just to be pedantic: around OS 2.0 I think (could be later, but it's there in 3.0) the system made the pixel aspect ratios for different resolutions much more explicit. You can for instance see them in the Screenmode preferences.

For NTSC lores it's 44:52. So stretching 320x200 according to that would result in 200 / 44 * 52 = 236.36 lines, so not exactly 4:3 = an aspect ratio of 1.33, but 1.35. (Strange that Commodore didn't use 40:48.)

For PAL, the pixels are square at 44:44, but 320x256 is not 4:3, but 5:4 = an aspect ratio of 1.25.

However, the screens were of course still 4:3. So on NTSC monitors and TVs, the borders above and below the 320x200 image would have to be just a hair larger than the ones on the sides, with for PAL noticeably larger borders on the sides than above/below.

In practice of course everything was analog, with TVs usually having not very accessible ways to stretch and center the display and monitors having them somewhere more reachable, so users would turn these to arrive at subjectively agreeable results.

So I guess my conclusion is that back in the day, it was easy to not care, but now with all our super exact monitors we're kind of forced to care and take a position.

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