Spectrum 512 and HAM6 comparison

[ROWBEARTOE]

In 1987 Spectrum 512 went head to head with Amiga's HAM-6 mode. In my opinion neither had a clear advantage over the other. Spectrum allowed 45 colors every scan line from 512 while the Amiga HAM-6 could display 16 colors and modify only 1 of the 3 RGB values from a preceding color from 4096 colors. I love color displays, and set out to draw lots of various ways to show all 512 of them. To my satisfaction (because I love Atari more than Amiga) the kind of pictures I made really couldn't be done on the Amiga HAM-6 mode. Enjoy. I realize in time, better software allowed better graphic displays for both machines as is evident from the photochrome pictures I uploaded. Enjoy. =)

[alexh]

Such a lame comparison.

Use a software assisted screen mode on the Amiga which is more of an equivalent to Spectrum 512 (e.g. Dynamic HiRes) rather than HAM6 and you'll get identical results.

[ROWBEARTOE]

I realize that drawings can be made using HAM-6 (320 colors on a scan line for example) that would look awful in Spectrum 512 as well. But I drew these pictures on my Atari ST, and I like them alot. I own an Amiga as well, and for the kind of color "art" I made, HAM-6 wouldn't satisfy me. I did mention they both had advantages over another- I never said one was better. Sorry for those who find this a "lame" comparison. But as a fan of the Atari ST, I rather enjoy this comparison. =)

[alexh]

Spectrum 512 is a software assisted screen mode and HAM6 is a fully hardware mode. It's not comparing like with like.

Use Dynamic HighRes, or another software assisted screen mode which changes the pallette on every scan line on the Amiga and you'll get the results identical to Spectrum 512.

I think you can use ADPro to convert to Dynamic HighRes.

Out of interest.. how did you convert your spectrum 512 pics to HAM-6?

[ROWBEARTOE]

Such a lame comparison.

Use a software assisted screen mode on the Amiga which is more of an equivalent to Spectrum 512 (e.g. Dynamic HiRes) rather than HAM6 and you'll get identical results.

Dynamic HiRes wasn't available in 1987, neither was Photocrhome. Dynamic HiRes allowed 640x400 with the option of no borders with only 16 colors per scan line. These pictures in most cases have more than 16 colors per scan line. Up to 40 I think? Amiga SHAM would do a much better good job at converting these pictures- But then again, Photochrome and SHAM and Dynamic HiRes and ? were not available in 1987, more like the early 1990's. 5! years after the original ST and Amiga. In the early 90's other computers offered better graphic hardware too. Software for both the ST and Amiga in 1987 was limited to Spectrum 512, Quantum Paint, and various Amiga HAM-6 programs. By 1990, the Amiga and ST offered better computers. More chip RAM, faster processors, etc.

[alexh]

Hmmm, I bet it was very close to 1987.

Some animations and viewers were posted to Aminet in 1989

http://aminet.net/search?query=dynamic+hires

[ROWBEARTOE]

Out of interest.. how did you convert your spectrum 512 pics to HAM-6?

It's a secret. Hahaha. After years of searching, I found a PC program called "Generalised Bitmap Module". It can read and convert all kinds of formats. I can convert 24-bit BMP files to Amiga LBM HAM-6 or HAM-8. So all I have to do is save Spectrum 512 pictures to BMP format, then convert them to display on my Amiga of PC.

[alexh]

I guess it could produce better results than any of the commercial paint tools on Amiga in 1987. I doubt any of them ever supported software enhanced screen modes even years later.

[ROWBEARTOE]

Hmmm, I bet it was very close to 1987.

Some animations and viewers were posted to Aminet in 1989

http://aminet.net/search?query=dynamic+hires

You are right about Dynamic HiRes. It was available in mid to late 1989 via Digiview gold. The New Tek Demo reel 3 looked great! Dynamic HiRes offered Amiga High Resolution BUT only 16 colors per scan line- similar to how the the Apple IIGS displayed graphics. SHAM which has HAM-6 per scan line- was 1990 at the earliest. Even SHAM though wouldn't convert these pictures perfectly- because I have more than 16 colors on a scan line seperated by the color black. And black R0 B0 G0 can not be modified to Cyan R0 B7 G7 without another "false" color being modified first. Sadly, my conversion program will not convert to SHAM, only HAM-6.

[beastie]

[...]
But as a fan of the Atari ST, I rather enjoy this comparison. =)

Without any additional explanations to these Amoeba fanboys and fellows... Me too.

Thanx.

[Examigan]

Interesting, I loved Spectrum 512 on my old Atari 520ST , and I later bought an Amiga 2000. The gradient fills possible with Spectrum 512 were awesome looking.
I wrote a review for a magazine in the late 80's I think, maybe early 90's about Unispec, the upgrade for Spectrum that let you do (among other things) antialiased lasso cut-and-paste, and you could use it as an accessory along side of other programs that you have loaded up.

[ozy2000]

Hmmm, I bet it was very close to 1987.

Some animations and viewers were posted to Aminet in 1989

http://aminet.net/search?query=dynamic+hires

You are right about Dynamic HiRes. It was available in mid to late 1989 via Digiview gold. The New Tek Demo reel 3 looked great! Dynamic HiRes offered Amiga High Resolution BUT only 16 colors per scan line- similar to how the the Apple IIGS displayed graphics. SHAM which has HAM-6 per scan line- was 1990 at the earliest. Even SHAM though wouldn't convert these pictures perfectly- because I have more than 16 colors on a scan line seperated by the color black. And black R0 B0 G0 can not be modified to Cyan R0 B7 G7 without another "false" color being modified first. Sadly, my conversion program will not convert to SHAM, only HAM-6.

Well you are being pedantic because in nature it's not exactly common for the human eye to generate such alternating artificially gaudy colours separated by a black vertical line

Whatever Spectrum 512 or other raster line palette changing software routines you have on the ST you can replicate the same in hardware using the copper chip on Amigas anyway with or without HAM mode being used. Classic example is the Magnetic Scrolls ST and Amiga full colour loading screens which were all better than any Spectrum/HAM images at the time anyway...even if they did use 50% cpu cycles on Amiga and 90% on the ST, they were very nice bits of eye candy and good technical examples of what 'extra' you could get out of both

Don't forget though that the DigiView 4 images produced can be in 320x512 mode for HAM6 if required not just 320x256 borderless lo-res Amiga HAM mode compared to the STs 320x200 screen with a huge border around it also, and with a lot of very good image processing built into Digiview available to automatically adjust out as much as possible any HAM fringing using the incredibly detailed 640x512 or higher 21bit internal colour data stored in the buffer as reference for Digiview to generate the images as Dynamic HAM lo-res/lo-res interlaced. A lot of the good pictures from Digiview were done with v4.1 software in my experience....I'll see if I have some magazine page scans of Digiview 4 in 300DPI or something to give an idea.

Hell I even remember loading in HAM interlaced images into Digiview 4 to re-render as dynamic ham lores to reduce fringing and then editing the worst of the carried over fringing using DigiPaint also from Newtek.

(if anyone is wondering I used to do some graphics 'work' for Black Knight the ill-fated games company in the late 80s so I had all the lovely kit...didn't ever get paid but I kept all their cameras and professional lighting equipment for messing me about )