OHP's are just completely mistifying me. I bought an old classroom type OHP, with 2 250W bulbs in it, with the change over switch.
Every time I hear about you lot talking about retro-fitting a new bulb and ballast, I'm lost. And I'm sure others are.
It's all very good discussing the matter of OHP's but some don't have a clue where to start. Like myself.
So help. Now. Please.
Anyhow, about my OHP, it uses the 2 prong 250W bulb that looks like the one in this photo, if it comes out that is.It didn't come out. oops
I know, I know, it's a REAL basic OHP, about 9 years old, but it works really well onto a dark wall, and it focuses perfect. I just can't see anything playing Halo or any other game on the xbox that is quite dark.
The bulb my OHP uses is like this one:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=2554728202&category=40001
So, can I modify this OHP to get a better bulb. The manufacturer says don't put a stronger bulb in it, but who listens to them, eh? I don't really know if a 250W MH bulb would be any good, I mean thats if I can find one that would be suitable for this OHP. And when I do find a website that sells MH bulbs, they never show pictures. By the way, I liv in the UK.
Is there anything on these sites:
http://www.uklightbulbs.co.uk/
or
http://www.bullnet.co.uk/shops/hydro/lighting.htm
or
http://www.stationerystore.co.uk/cg...//www.stationerystore.co.uk/index/31170.shtml
Anyone help? I usually try not to ask ofr help cause no-one usually helps people starting simple questions, but we all start somewhere, and I'm sure you where in my position some time ago.
cheers guys and gals.
Every time I hear about you lot talking about retro-fitting a new bulb and ballast, I'm lost. And I'm sure others are.
It's all very good discussing the matter of OHP's but some don't have a clue where to start. Like myself.
So help. Now. Please.
Anyhow, about my OHP, it uses the 2 prong 250W bulb that looks like the one in this photo, if it comes out that is.It didn't come out. oops
I know, I know, it's a REAL basic OHP, about 9 years old, but it works really well onto a dark wall, and it focuses perfect. I just can't see anything playing Halo or any other game on the xbox that is quite dark.
The bulb my OHP uses is like this one:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=2554728202&category=40001
So, can I modify this OHP to get a better bulb. The manufacturer says don't put a stronger bulb in it, but who listens to them, eh? I don't really know if a 250W MH bulb would be any good, I mean thats if I can find one that would be suitable for this OHP. And when I do find a website that sells MH bulbs, they never show pictures. By the way, I liv in the UK.
Is there anything on these sites:
http://www.uklightbulbs.co.uk/
or
http://www.bullnet.co.uk/shops/hydro/lighting.htm
or
http://www.stationerystore.co.uk/cg...//www.stationerystore.co.uk/index/31170.shtml
Anyone help? I usually try not to ask ofr help cause no-one usually helps people starting simple questions, but we all start somewhere, and I'm sure you where in my position some time ago.
cheers guys and gals.
true about simple questions...alas.
Here's a couple of thoughts I brought to a thread but I didn't get much in terms of ideas back from my post.
I've got a 3M 2150, and it also uses those bulbs. This projector has a reflector, a condensor, and a triplett projection lens, but it's only 2k lumens. For the most part, a great OHP.
What I envision doing is removing the whole light bulb mounting system from my OHP and using some material to position the 250W MH bulb right in front of the reflector. there's plenty of room in the chasis to mount the ballast. The only possible issue is if the MH buld is significantly bigger than the existing bulb, but I don't think that will be a proble. As it is now, the OHP has the bulb selector switch like yours does -- thus, the bulbs are actually off-center in the reflector.
http://www.diylabs.org sells the MH bulb and ballast that many here use.
When the manufacturer advises against a stronger bulb, I believe the mean in conjunction with the existing ballast in the OHP. Since you'd be replacing the ballast, you'd be okay -- you can't just plug a MH bulb into the existing bulb socket, if you see what I mean.
Here's a couple of thoughts I brought to a thread but I didn't get much in terms of ideas back from my post.
I've got a 3M 2150, and it also uses those bulbs. This projector has a reflector, a condensor, and a triplett projection lens, but it's only 2k lumens. For the most part, a great OHP.
What I envision doing is removing the whole light bulb mounting system from my OHP and using some material to position the 250W MH bulb right in front of the reflector. there's plenty of room in the chasis to mount the ballast. The only possible issue is if the MH buld is significantly bigger than the existing bulb, but I don't think that will be a proble. As it is now, the OHP has the bulb selector switch like yours does -- thus, the bulbs are actually off-center in the reflector.
http://www.diylabs.org sells the MH bulb and ballast that many here use.
When the manufacturer advises against a stronger bulb, I believe the mean in conjunction with the existing ballast in the OHP. Since you'd be replacing the ballast, you'd be okay -- you can't just plug a MH bulb into the existing bulb socket, if you see what I mean.
ham_aneq
I had the same problem with bulb purchases online in the U.K. The yanks have everything cheaper and more plentiful! Try www.commercial-lighting.co.uk they have a huge selection of discharge lighting( complete with pictures!), they are the cheapest online retailer I could find. Interms of a lighting rig, i'd suggest retrofitting your OHP with a metal halide setup. MH gives a whiter light than halogen (steer clear of sodium or mecury vapour) and is cooler, though not massively. If you want to stick with the OHP original bits and bobs contact the manufacturer for available bulb types and wattages.
For an Metal Halide (MH) setup you need;
-an MH bulb £25, that runs on sodium control gear, other MH bulbs run on mercury control gear which is more expensive.
-Sodium control gear (called a ballast by most growshops) www.growell.co.uk do a unit for £70.
-an E40 lampholder (giant edison) local electrical wholesaler £10.
these three elements are the cheapest way of doing a MH setup, you may have come across HQI metal halide rigs, whilst these are smaller they are more expensive.
My setup is a 400w MH rig, basically this consists of, a venture "whitelux" bulb(£33 including vat+delivery) this metal halide bulb will run on sodium control gear( commonly refered to as a ballast at most hydroponic growshops), My 400w ballast came from a grow shop in bristol but they are available online. The ballast gives the power to the bulb. 400w watts will give you a good dose of projection power, though you will need to fit some fans to your OHP.
What panel are you using? I used a stripped down benq 557s monitor. A good site for links to plans and theories is http://www.diyaudio.com/wiki/index.php?page=Video
I had the same problem with bulb purchases online in the U.K. The yanks have everything cheaper and more plentiful! Try www.commercial-lighting.co.uk they have a huge selection of discharge lighting( complete with pictures!), they are the cheapest online retailer I could find. Interms of a lighting rig, i'd suggest retrofitting your OHP with a metal halide setup. MH gives a whiter light than halogen (steer clear of sodium or mecury vapour) and is cooler, though not massively. If you want to stick with the OHP original bits and bobs contact the manufacturer for available bulb types and wattages.
For an Metal Halide (MH) setup you need;
-an MH bulb £25, that runs on sodium control gear, other MH bulbs run on mercury control gear which is more expensive.
-Sodium control gear (called a ballast by most growshops) www.growell.co.uk do a unit for £70.
-an E40 lampholder (giant edison) local electrical wholesaler £10.
these three elements are the cheapest way of doing a MH setup, you may have come across HQI metal halide rigs, whilst these are smaller they are more expensive.
My setup is a 400w MH rig, basically this consists of, a venture "whitelux" bulb(£33 including vat+delivery) this metal halide bulb will run on sodium control gear( commonly refered to as a ballast at most hydroponic growshops), My 400w ballast came from a grow shop in bristol but they are available online. The ballast gives the power to the bulb. 400w watts will give you a good dose of projection power, though you will need to fit some fans to your OHP.
What panel are you using? I used a stripped down benq 557s monitor. A good site for links to plans and theories is http://www.diyaudio.com/wiki/index.php?page=Video
cheers bexeley, Unfortunately, I'm not onto the lcd monitors as of yet, I'm working with a polaroid polaview 3000, although I do hope to upgrade when money allows in 6 months time.
One of the things that bothers me when buying this stuff is will it fit? This OHP cost me 20 quid so its pretty basic. i'll try and attatch a picture to show the insides of it, and you can see for yourself if such a new ballast and control gear would work. No, in fact I'll send you pictures by e-mail. Whats your email? The pictures are only about 110kb, just too big to attatch here. E-mail me personally at greg.calder@strath.ac.uk if you want.
Is this the item you are talking about:
http://www.growell.co.uk/p/0672/Power_Plant_Horticultural_Lighting_Ballasts.html
Will this thing sit inside the OHP or outside it? It looks pretty big to me. I mean, where does the bulb go? Also, what do you mean by giant edison?
Talking about another fan in the OHP, what do you mean, more noise? More electricity consumption?
Are you talking about a wee small PC fan or something like that cause I wouldn't know where to start with that.
I'm eager to learn, thats a start.
If you could point me in the correct direction via web site addresses(full), I would be very grateful
One of the things that bothers me when buying this stuff is will it fit? This OHP cost me 20 quid so its pretty basic. i'll try and attatch a picture to show the insides of it, and you can see for yourself if such a new ballast and control gear would work. No, in fact I'll send you pictures by e-mail. Whats your email? The pictures are only about 110kb, just too big to attatch here. E-mail me personally at greg.calder@strath.ac.uk if you want.
Is this the item you are talking about:
http://www.growell.co.uk/p/0672/Power_Plant_Horticultural_Lighting_Ballasts.html
Will this thing sit inside the OHP or outside it? It looks pretty big to me. I mean, where does the bulb go? Also, what do you mean by giant edison?
Talking about another fan in the OHP, what do you mean, more noise? More electricity consumption?
Are you talking about a wee small PC fan or something like that cause I wouldn't know where to start with that.
I'm eager to learn, thats a start.
If you could point me in the correct direction via web site addresses(full), I would be very grateful
That growell link is spot on. A ballast is typically just smaller than shoe box and has to be outside the ohp. smaller ballasts are available from narva.co.uk but are more expensive. giant edison is a type of bulb holder, much like a screw fit but bigger. all single ended MH bulbs use this type of lamp holder fitting refered to as an E40 fitting in the trade.
Heat is definately an issue with high power lighting and your ohp will need an air intake and exhaust fans. these can be 80mm computer case fans, there cheap, just £2 approx, but they run on 12v. I use an old hornby transformer to power these.
As i said before the link, http://www.diyaudio.com/wiki/index.php?page=Video has over 800 links to sites covering just about all you to know. any specific questions just e-mail me at globalhypermegacorp@DELETETHISBIThotmail.com an i'll try to help..........
Heat is definately an issue with high power lighting and your ohp will need an air intake and exhaust fans. these can be 80mm computer case fans, there cheap, just £2 approx, but they run on 12v. I use an old hornby transformer to power these.
As i said before the link, http://www.diyaudio.com/wiki/index.php?page=Video has over 800 links to sites covering just about all you to know. any specific questions just e-mail me at globalhypermegacorp@DELETETHISBIThotmail.com an i'll try to help..........
Alan at diylabs.org sells IceCap electronic ballasts for very low price and also for 220VAC power (close enough for 240VAC systems in Europe).
I looked at diylabs.org but they only do 250W MH ballasts, I would prefer 400W, cause I want to be able to see everything on the screen, including being able to play games like halo on the xbox. I can only presume a 250W MH wouldn't show the whole quality, which with a 640*480 polaroid 3000 panel, you really need the best quality you can squeeze out of the set-up. Maybe I'm wrong thouigh, I dunno? Anyone like to disagree.
a decent reflector will give even light distribution across the panel, aswell as having the light source at the f1 point for the OHP fresnel (this being the distance the current bulb is from the fresnel inside the ohp, ie the focal length of the fresnel). a good demo of this is to hold a fresnel over a lamp whilst moving it up and down , the distance at which the light fills the whole of the lense is the focal length. it's amazing how much difference a slightly misaligned light source makes to the image brightness. a 400watter will give better viewing in half light conditions and allow a bigger image but at the high heat cost.
Hmmmm, you see these guys with 575WMH set-up's in their OHP's, I wonder how many fans they've got in them babies.
Instead of the expensive ballasts at the website you mentioned, how about this one:
http://www.1000bulbs.com/shopping/shopexd.asp?id=982
I don't know if this would be unsuitable because of the electricity ratings might be different.
Instead of the expensive ballasts at the website you mentioned, how about this one:
http://www.1000bulbs.com/shopping/shopexd.asp?id=982
I don't know if this would be unsuitable because of the electricity ratings might be different.
looks like i paid forty quid for the metal box my control gear is housed in!
only thing with the american parts is the mains voltage rating being 110-120v or there abouts. the UK's is double that, at 220-240v so a step-up transformer would be necessary.
But something i have found, much to my dismay, with my first stripped monitor rig is that the panel and lamp frequencies are out of synq, thus i am getting a flickering projection, arrgh!! it's not to bad, but annoying nonetheless, it may be due to the cheap magnetic ballast(excluding metal case lol). Heard some where that electronic ballasts don't give this problem with 60hz TFT's. Am gonna search posts or contact an electrical engineer for advice........
only thing with the american parts is the mains voltage rating being 110-120v or there abouts. the UK's is double that, at 220-240v so a step-up transformer would be necessary.
But something i have found, much to my dismay, with my first stripped monitor rig is that the panel and lamp frequencies are out of synq, thus i am getting a flickering projection, arrgh!! it's not to bad, but annoying nonetheless, it may be due to the cheap magnetic ballast(excluding metal case lol). Heard some where that electronic ballasts don't give this problem with 60hz TFT's. Am gonna search posts or contact an electrical engineer for advice........
right, so you're saying that I should buy only british things then to avoid complication. Okay. I'm gonna see how some other auctions go for better OHP's, and I'll fit a better bulb into one of them if I need to. This old classroom OHP was supposed to stay in the classroom by the looks of it.
I put my results of my temporary set-up on the following link. They're all right, I would have taken some more when I got the tripod for me camera but the other bulb went. Darn. The pictures are taken with a polaroid polaview 3000, 250W OHP and a bed sheet cloth(it's just temporary as I said).
It shows up monsters inc amazingly, and combined with an xbox and home theatre amp, it sounds excellent. Not bad for 130 quid.
http://uk.photos.yahoo.com/ham_anegg
Oh by the way, the size of picture is 80"-85".
I put my results of my temporary set-up on the following link. They're all right, I would have taken some more when I got the tripod for me camera but the other bulb went. Darn. The pictures are taken with a polaroid polaview 3000, 250W OHP and a bed sheet cloth(it's just temporary as I said).
It shows up monsters inc amazingly, and combined with an xbox and home theatre amp, it sounds excellent. Not bad for 130 quid.
http://uk.photos.yahoo.com/ham_anegg
Oh by the way, the size of picture is 80"-85".
good looking results! are you getting a hotspot onscreen?
The thing with american parts is the shipping costs, obviously with u.k. next day delivery, an impatient sod like me can have things near instantly lol!. My flickering was caused by british parts. Though as my bad experience with single ended MH shows, patience is definately a virtue.
Try giving everything a good clean; lense, fresnel, panel, the lot. This may help, another thing to look at is getting a triplet lense as a replacement for the current ohp lense (doublet lense). Triplet lense's give much better focus.
Those short life bulbs are a pain!! replacements, cheap from www.bltdirect.co.uk
I just switched backed to halogen! i've found the contrast better, MH seem's a bit washed out, too white..
The thing with american parts is the shipping costs, obviously with u.k. next day delivery, an impatient sod like me can have things near instantly lol!. My flickering was caused by british parts. Though as my bad experience with single ended MH shows, patience is definately a virtue.
Try giving everything a good clean; lense, fresnel, panel, the lot. This may help, another thing to look at is getting a triplet lense as a replacement for the current ohp lense (doublet lense). Triplet lense's give much better focus.
Those short life bulbs are a pain!! replacements, cheap from www.bltdirect.co.uk
I just switched backed to halogen! i've found the contrast better, MH seem's a bit washed out, too white..
There isn't anything wrong with my picture in the least, which is quite strange considering I just bought the panel and OHP and stuck them together. No real adjeustments have been made. I just want to be able to display Halo on the xbox, thats all, because that gives an amazing contrast in colours, plus it's got lots of dark scenes so I cannae play it now.
Hows about the metal halide st ups that they are selling, bexeley?
http://www.bltdirect.co.uk/cat351_1.htm
It looks mighty big though, so probably its not useable in an ohp.
http://www.bltdirect.co.uk/cat351_1.htm
It looks mighty big though, so probably its not useable in an ohp.
The ohp+tft panel is an all in one , called the NOBO INTEGRA POWERLITE its a little smaller than your average ohp (8" X 12" X 13") i get a clear image in daylight ,the only thing ive changed is the condenser lens.the lamp it takes is a 575 watt m/h
ham-anegg it has 1 fan,which blows cool air on the bulb and 1 in the tft panel(one of those long barrel type fans)
lee
ham-anegg it has 1 fan,which blows cool air on the bulb and 1 in the tft panel(one of those long barrel type fans)
lee
Attachments
Hey..there is no problem in purchasing online. Search on Google and you will find a site that will provide you with a good commercial lighting products. You can purchase from Industrial Lights Veelite UK | LED Lighting Factory Warehouse this site will help you a lot.
Wish you Good Luck.
Wish you Good Luck.
- Status
- Not open for further replies.