Author Topic: How useful is a DCTV (Read 3411 times)

Ral-Clan · « **on:** November 28, 2006, 09:10:52 PM »

Hi, I was just given a DCTV (not a CDTV) 24 bit graphixy box in a pile of Amiga stuff. It's a box that goes between your Amiga's RGB port and monitor, and can display images in pseudo 24-bit colour, but only with programs that have the ability to output to it. (seems like most of the good graphics software had 'drivers' for it).

http://www.amiga-hardware.com/showhardware.cgi?HARDID=282

It also can capture still colour images from a video source (but it's very slow at this).

For those who have a DCTV, how useful is something like this nowadays? Now that we have RTG graphics cards, scanners, digital cameras, etc.

I read all the old reviews, and in the mid-90s, people generally seemed to love it. Apparently, it was very good for the price. It seems like some people did some commercial type work with it too.

I noticed now, though, they seem to be generally unwanted - going for $5 on Ebay or not selling at all.

I already have a nice A2000 with Picasso II as my main Amiga, but I'm thinking this little DCTV could breath new life into an old A500 setup....actually making it useful for doing some semi-serious graphics work. Like lo-res (640x480) art and animations, etc.

Anyone have any experiences with this or comments?

How does it like OS3.x?

560SL · « **Reply #1 on:** November 28, 2006, 10:52:19 PM »

Yeah, I have one of those too lying around somwhere. Cant remember where I got it from, probably from a pile of A500's on their way to the junkyard.

I must admit I never tried it though. I recall giving up when I found out that they were extremely slow at grabbing pictures (5-6 seconds/frame I believe).

Would be nice too see how the image quality compares to the FG24. Sometimes, it would be worth the extra waiting to get the better quality.

Im gonna try it out, any year now.

Rabbi · « **Reply #2 on:** November 28, 2006, 11:28:08 PM »

It's good for pre-AGA Amigas without video cards, IMHO. Animations & stills are simply stunning due to the range of colors available. It was probably the cheapest way at the time to add more colors than unexpanded pre-AGA Amigas offered, and you didn't need a video slot to use it, either.

If you can't find the original Digital Creations (now Play) drivers, send me an e-mail.

Capture is slow and not very clear. I'd guess it would also depend on the video camera source.

There is also a DCTV RGB Converter so that it could be hooked up to a genlock. This was sold seperately. It hooks in between the pass-through of the DCTV and the genlock. I've got all 3, the DCTV, the RGB Converter, & the SuperGen SX genlock.

yogisumo · « **Reply #3 on:** November 29, 2006, 12:26:13 AM »

You need a good source for good captures.

Capturing from a cheap vcr is problematic.

You end up with bad captures if the still frame is not stable.

Also, you're essentially capturing NTSC/PAL video which is not very high resolution ( 200 lines res? ).

It's strength is video and animation if you're end product is going to video.

mr_a500 · « **Reply #4 on:** November 29, 2006, 12:35:55 AM »

DCTV is the second best thing I've ever bought for my A500 (the first being Viper 520). I love it. The software is very well written and works perfectly in all Workbench versions from 1.3 to 3.9 (I never tried in 1.0 to 1.2). I've never ever had a crash with DCTV software no matter what patch or configuration I used. DCTV Paint is probably the best Amiga paint program I ever used.

DCTV 24-bit output is composite, not RGB meaning it can't be used to display Workbench or application screens. Composite is a bit blurry for things like text or fine detail (use dynamic hi-res instead). My main use for DCTV is to display images downloaded from the internet (certainly better than HAM) and to scan still images from DVD or a video camera pointed at a picture or still object (like a scanner). Scan speed is pretty slow and it's important that the image is still or you get a screwed-up image.

DCTV was meant to be used with Commodore 1084 monitor which allows you to easily switch between composite and RGB - otherwise you need a TV or composite monitor to display the DCTV images. 24-bit DCTV files (which are really 4-bit) are about 15% the size of a 24-bit IFF, meaning 24-bit animations are much faster.

The best programs to use with DCTV are:
ImageFX (render to DCTV - but crops at 736 pixel width)
AdPro (DCTV operator - make large DCTV images 1280x2048?)
VistaPro (render to DCTV)
JPEGonDCTV (quickly display jpeg on DCTV)
DCTV-Viewer96 (to view scrolling DCTV images larger than 736x482)

beller · « **Reply #5 on:** November 29, 2006, 03:02:25 AM »

Ah...thanks for the reminder mr_a500!

I'd forgotten that Vista renders to DCTV. I picked up one last year, with all the appropriate disks and manuals for cheap but haven't really hooked it up to play with it.

My partner, Jim Meyer, and I wrote the manual for DCTV. As I recall, I did the digitizer and Jim handled the Paint software. The digitzer looked great if you had a nice video cam as the source, or something with a digital frame store you could grab. I still remember playing with it the evening we started work on the manual. The graphics were better than anything I'd seen on a computer up to that point. It was a very fun project to watch take off...

Ah, good times. I keep my DCTV for nostalia.

Bob

mr_a500 · « **Reply #6 on:** November 29, 2006, 03:58:04 AM »

Once again, nice manual Bob! :-)

A few miscellaneous points about DCTV:

If you're scanning from DVD, you may notice that there are horizontal lines at regular intervals on the scanned image. This only happens with certain DVDs. I think it's a form of copy protection or something because it only happens on DVDs from certain movie studios.

JPEGonDCTV works best with images smaller than 736x482. Larger images are squashed to fit (looks blurry or bad aspect ratio). For large images it is best to load into ImageFX and crop the section you want (using high-res interlace preset size) then render to DCTV. The image can be viewed with any IFF viewer that opens its own screen (I like Visage). If you don't want to crop, use ADPro to convert the entire image to DCTV and DCTV-Viewer96 to view. I wish Visage could have supported scrolling DCTV, because DCTV-Viwer96 is not the greatest (written in AMOS).

GIF images can also be viewed with DCTV, but their palette must first be changed from CMAP to RGB (use ImageFX or ADpro). PNG is already in RGB format so there is no problem with that.

Ral-Clan · « **Reply #7 on:** November 29, 2006, 04:16:37 AM »

Great! Sounds like the DCTV is something I want to keep then rather than sell. I think it could make an Amiga 500 a nice little true-colour graphics workstation for simple 2D bitmap stuff and animation work.

Good to see that after all these years people still love this product. Honestly, all the reviews I found for it on the web were very positive.

As for the framegrabbing part....I probably won't use it much, but if I do then I'd probably just grab images from the NTSC video output of my digital camera.

Thanks for the opinions!

mr_a500 · « **Reply #8 on:** November 29, 2006, 04:46:34 AM »

You can see a couple images I scanned with a video camera attached to DCTV in this post here. In this case DCTV came in handy because I don't have a digital camera.

A few more points about DCTV:
When converting a DCTV image to JPG, GIF or PNG (like I did in the above link) you need to change the aspect ratio from NTSC (assuming NTSC DCTV) to 1:1 or it'll look squashed vertically when viewed on non-Amiga computers. Use the ADPro operator "NTSC to Square". (ImageFX also has a way to change aspect ratio, but no matter what I did, it didn't work.) Also, a DCTV scan will look a bit blurry so you need to sharpen it a bit. Usually, after changing aspect ratio, I use the Sharpen feature (set to 128) in ImageFX. If you want it really sharp, you need to halve the image size before sharpening.

(This is probably more information than you need, but maybe somebody will find this useful... or maybe not ;-))

amigadave · « **Reply #9 on:** November 29, 2006, 04:48:58 AM »

The DCTV was/is a great piece of hardware. I went to a show once and saw a stock A3000 playing from the hard drive, the complete "Back to the Future II" movie that had been converted, "frame by frame" to the DCTV format. I was amazed and decided that I had to get one.

I am surprised that more was not done with the DCTV format and hardware and the Amiga, as it gets great display results with tiny file sizes and full screen, full color animations can be run with just an 68030 and SCSI-2 (and perhaps even IDE) hard drives. DCTV Paint was recognized as one of the best paint programs available for the Amiga for a long time.

I am a strong believer in DCTV and early Amigas (that's why I own more than a few of them). :-D

Ral-Clan · « **Reply #10 on:** November 29, 2006, 02:47:03 PM »

Those screen grabs don't look bad at all - especially considering this is 1991 era hardware. I can see why it was so popular at the time.

Just a question: I ALREADY have an internal (videoslot) scandoubler and Picasso II graphics card on my A2000. Will this conflict with the DCTV (I don't plan to use the DCTV with this computer, but I want to test it with this A2000 as I don't have the space to set up an A500 for it yet).

i.e. with this setup is there still a video signal going to the old RGB monitor port on my A2000?

With this setup I normally boot to an 800x600 16-bit Workbench screen. What would happen if I ALSO had an old 1084 monitor hooked up to the RGB port at the same time? I assume the same 16-bit 800x600 signal would also be sent to the RGB port and could fry my 1084. Or does RTG software like Cybergraphix totally shut off output to the old RGB port and re-direct it to the graphics card when high scan rates like this are run?

If I plan to test the DCTV by temporarily hooking it and my old 1084 to my normally unused RGB port, will I fry them both when my Amiga starts up in 800x600 (or higher).

So how does this all work? Since I went scandoubler/RTG I've never used the old monitor port.

Thanks.

amigadave · « **Reply #11 on:** November 29, 2006, 04:34:58 PM »

Quote

ral-clan wrote

Just a question: I ALREADY have an internal (videoslot) scandoubler and Picasso II graphics card on my A2000. Will this conflict with the DCTV.

>> No, it will work fine. <<

i.e. with this setup is there still a video signal going to the old RGB monitor port on my A2000?

>> I am pretty sure the signal is still present at the stock 23 pin RGB port on the A2000 that will have the DCTV connected to it, but the screen display you are using for workbench is a Picasso II display mode, so that will not be present on the stock RGB port. When you start other programs (such as the DCTV software that is not mode promotable, it is passed through the Picasso II card unchanged. These display modes should be available on the stock RGB port connected to the DCTV.<<

With this setup I normally boot to an 800x600 16-bit Workbench screen. What would happen if I ALSO had an old 1084 monitor hooked up to the RGB port at the same time? I assume the same 16-bit 800x600 signal would also be sent to the RGB port and could fry my 1084. Or does RTG software like Cybergraphix totally shut off output to the old RGB port and re-direct it to the graphics card when high scan rates like this are run?

>> There is no way for the Picasso II card to send the 16-bit 800x600 signal back through the stock RGB port and hurt your 1084. I think all you will get is a grey or black screen on the 1084 when a display mode from the Picasso II is in control.<<

If I plan to test the DCTV by temporarily hooking it and my old 1084 to my normally unused RGB port, will I fry them both when my Amiga starts up in 800x600 (or higher).

>> NO <<

So how does this all work? Since I went scandoubler/RTG I've never used the old monitor port.

Thanks.

You are welcome, hope this helps. You also need to hook up a composite cable to the 1084 and switch back and forth from RGB to Composite to see the images correctly, and hook up the DCTV cable to the parallel port to do scans.

Have fun.

fiat1100d · « **Reply #12 on:** November 29, 2006, 05:27:20 PM »

Quote

amigadave wrote:
The DCTV was/is a great piece of hardware. I went to a show once and saw a stock A3000 playing from the hard drive, the complete "Back to the Future II" movie that had been converted, "frame by frame" to the DCTV format. I was amazed and decided that I had to get one.

Frame by frame? So how much time was needed for the whole conversion? I read of many seconds per frame!!

T3000 · « **Reply #13 on:** November 30, 2006, 02:13:06 AM »

I tried using a stock A500 and a DCTV for video camera still grabs long ago. Ya might want to use a DKB Megachip with the DCTV on the A500. Worked real nice on my A2000/030 8mg ram and Megachip. 24 bit paint program was awesome. ...at the time anyway.

amigadave · « **Reply #14 on:** November 30, 2006, 03:21:50 AM »

Quote

fiat1100d wrote:
Quote

amigadave wrote:
The DCTV was/is a great piece of hardware. I went to a show once and saw a stock A3000 playing from the hard drive, the complete "Back to the Future II" movie that had been converted, "frame by frame" to the DCTV format. I was amazed and decided that I had to get one.

Frame by frame? So how much time was needed for the whole conversion? I read of many seconds per frame!!

I don't know how long it took them to convert each frame of the movie to an animation frame in DCTV format, but I am sure they used a batch processing program to do it. What I don't know is what method they used to digitize the movie frames/fields into digital format to then convert to DCTV format from 24bit. All I know is that I was blown away that the movie was streaming from the hard drive and displaying at full screen, full speed, full color composite NTSC resolution from a stock A3000. Everyone that saw it was looking under the table to try to find the VCR that must have been playing a tape. It was an unbelievable accomplishment for the time, given the computing power and hard drive performance available at the time (around 1990 I think).

Author Topic: How useful is a DCTV (Read 3411 times)

Ral-Clan

How useful is a DCTV

560SL

Re: How useful is a DCTV

Rabbi

Re: How useful is a DCTV

yogisumo

Re: How useful is a DCTV

mr_a500

Re: How useful is a DCTV

beller

Re: How useful is a DCTV

mr_a500

Re: How useful is a DCTV

Ral-Clan

Re: How useful is a DCTV

mr_a500

Re: How useful is a DCTV

amigadave

Re: How useful is a DCTV

Ral-Clan

Re: How useful is a DCTV

amigadave

Re: How useful is a DCTV

fiat1100d

Re: How useful is a DCTV

T3000

Re: How useful is a DCTV

amigadave

Re: How useful is a DCTV