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Posted: Tue Jan 29, 2008 6:53 pm
by Peter Copestake
I have been 'away' for ages and don't know how this forum works now. Is the there a technical forum as well and if so how do I access it?
If there isn't can someone please tell me if the small data projectors (about the size of a packet of large biscuits) are any good for video projection. Is it a question of limited throw, limited colour-range, definition or what?
Our club is intending to get a lap-top to use for demos at meetings and have been advised to get a projector that matches it. When our chairman saw one, described above, he got very excited that he wouldn't have to carry our Sony HS-2
(4.5 Kg) to shows. yes, he's getting on a bit and has a dicky ticker.
Also, my main DVD burner gives out after 7 discs and is "unsuccessful" until it cools down. Is it heading for the scrap heap?
Thanks in advance for any help,
Peter Copestake

Posted: Tue Jan 29, 2008 9:05 pm
by Dave Watterson
Welcome back, Peter.

There is a private email group which sends round robin emails to one another on technical issues. Access to that is restricted to IAC members ... which is why I left it because I prefer open access.

There has been a suggestion that we should have an open technical forum here - which could be done, but there are already several similar forums (? fora) elsewhere.

Maybe someone who is in the email group could email you privately with a reminder of how to hook up to it. (Please do not give details here in public.)

As to the specific queries ... I think the only answer with projectors is to try them. My main concern is that small data projectors are designed to present spread-sheets and powerpoint slides in offices rather than movies - they give even brightness whereas real cinema presentation has a slight extra brightness at the centre. But few clubs seem to care about such niceties. Office machines are usually best set about a yard away from a wall and project an image about 30 inches wide on the wall.

As for the DVD burner - I don't know. The one built in to my edit suite never likes being asked to burn more than one. If I set it to three it quits in the middle of the second one !!!


Posted: Tue Jan 29, 2008 11:19 pm
by Stephen
certainly recommend this one:-

LiteOn LH-20A1H-483C 20x DVD±R/RW/RAM DL Lightscribe

don't pay more than 18 UKP

copy above and google...

Posted: Wed Jan 30, 2008 1:36 am
by billyfromConsett
Data projection and video projection are pretty different specs.

Video projectors are set to project images in dark rooms, so being seriously over-bright is maybe not that much of a good idea. They also allow you to easily switch image ratio ie 4:3 to 16:9 with a press of a remote.

My projector is a Panasonic PT-AX100, which at less than £800 is absolutely fantastic!

It's got loads of brightness, but excels in picture quality, colour reproduction and quietness, and is also suitable for high-definition projection. (future issues)

see ... conclusion or ... /index.php.

Re your DVD writer - get a new one, they're so cheap at about £20, it's a no-brainer.

Posted: Wed Jan 30, 2008 2:06 pm
by Dave Watterson
By chance I bought the current issue of Personal Computer World magazine today and found a feature on projectors.

The one with the lightest weight in their test was 1.4 Kg

That was the Optoma EP1691 list price £939. Their review was pretty positive. It gives out 2,500 lumens, gets a bit hot, is not too noisy, has internal speakers (though not recommended for a show!), can go up to 370 inch wide image!

They reckon that while it is not suitable for home cinema enthusiasts (i.e. watching DVDs of commercial movies) it is a go-anywhere all-rounder.

A and C Audio ( are offering it at £757.88 including VAT.


Posted: Wed Jan 30, 2008 10:49 pm
by Willy
Dave Watterson wrote:Welcome back, Peter.

As for the DVD burner - I don't know. The one built in to my edit suite never likes being asked to burn more than one. If I set it to three it quits in the middle of the second one !!!

I thought I was the only one with that problem because I am not so good at using my computer. I thought that each time I had done something wrong. It's a very expensive problem. Each time you lose a DVD. It means money. So each time I have to control myself and to ask my Benq to burn only one, instead of two or three.

Posted: Thu Jan 31, 2008 4:49 pm
by Ray Williamson
The projector suggestions are interesting. What pixel count do they have?
The last time I looked for a 1080i one it was over £3000.
I had to have a lie down!
Most office-type machines seem to be 800 x 600.

Posted: Thu Jan 31, 2008 6:46 pm
by stingman
There are also two types of projecting the image.
One uses standard projector LCD displays.
The other uses a spinning prisum. I think that it is this one that gives my eyes and brain a headacke! With this one, when there is a bright white bit in the picture, and you look away. You get the remains of a rainbow in the corner of your eye.
i think that we covered this last year on the forum.


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Posted: Thu Jan 31, 2008 7:06 pm
by Peter Copestake
Thanks to everyone who replied to my queries. Thanks also to Jan for taking on the webmaster role, and to the people who started it and ran it til now including Richard who kindly sent me a new password recently just afterI found my original one!
I very carefully installed my new DVD writer only to find when I switched on that the condition of my Pri-master was BAD!
For those of you who don't know, that was because I hadn't moved a little thingy from pin 1 to pin 3. Perhaps if I'd used the Lite-on model recommende by Stephen it wouldnt have needed this but with a Pioneer, available locally and used by one of my club colleagues, while it tells you not to water your plants over it the instructions don't start with 'move the thingy if you don't want the computer to think this is the C drive'!
We'll do more research on the projectors. Thanks again, Peter.

Posted: Thu Jan 31, 2008 8:32 pm
by Dave Watterson
Ray said:
The projector suggestions are interesting. What pixel count do they have? The last time I looked for a 1080i one it was over £3000.
The Optima is 1024x768 pixels and is compatible with 720p as well as 1080i.

Stingman said:
There are also two types of projecting the image.
DLP (Digital Light Processing) projectors have chips with thousands of tiny mirrors on them (one per pixel) which physically move up a little to bounce light through the lens and down again to stop doing so. They reflect the white projector bulb's light. Colour is achieved by a spinning wheel of colour filters and the chip mirrors are timed to flash when the appropriate colour is in front of them. It is all pretty Heath-Robinson in concept but it works. Early models had a simple colour wheel and some people (mainly young people) were aware of a slight rainbow fringe sometimes. Modern colour wheels have many more segments and the rainbow effect is hard to spot indeed.

LCD (Liquid Crystal Display) projectors use a prism to split the bulb's light into three beams - each of which passes through a different colour of liquid crystal display panel fitted with polarising filters. The filters are opened or closed to let light through.

For sheer quality the old CRT (cathode ray tube) projectors take a lot of beating but they are very big, heavy and expensive.

Most modern projectors do a good job ...


Posted: Fri Feb 01, 2008 10:01 am
by stingman
Your Brain is like a library Dave. Thank you for your wisdom on `How Video Projectors Work`. May be if you pad it out a bit, you could turn it into a book.

Thanks Dave for calling me one of the `young people`! I feel and still act like one, I wouldn`t want it any other way. When I play football twice a week, I leave the young people (younger then me!) running out of energy. They use it all up in 10 minutes! I, on the other hand are like a steamengine. Just call me old Glory!
So I now have it in writting. Thanks Dave.


Posted: Fri Feb 01, 2008 11:57 am
by Dave Watterson
Your Brain is like a library Dave.
You mean faintly damp smelling, filled with out-of-date info and no new stock ?!?!? (Apologies to all desperately underfunded librarians everywhere - when I am king there will be budgets and staff again.)

Actually I'll reveal my two secret weapons:
  • is amazing - it starts with simple explanations and has links to take you to any depth you want studying a subject - which has broadly reliable info on all sorts of things (I google for "topic" + wiki and that gets me straight to useful info)
As for youthfulness - you personify it, Ian. You have enough energy for a small power station!


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Posted: Fri Feb 01, 2008 12:10 pm
by Peter Copestake
I forgot to say that, when PROPERLY INSTALLED the Pioneer did indeed print 14 DVDs without problems. My new Canon iP4500 printer however went AWOL twice while printing 21 discs. Switched off and on again = OK. It's a funny machine - has to go through the same rigmarole for each disc - click 'print', click 'print' on the next window, wait a bit (which is when it went wrong) do what it says and click 'OK'.
However, the results are very good for the discs and photos.