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cardiomac
9-Jan-2012, 08:16
Hi all. I just wanted to let everyone know that I am offering a new design LED lamp house for the Omega D-series variable contrast enlargers. This product came out of work I did for myself to make a replacement for the incandescent bulb of my Omega D2. It turned out pretty well so I thought I would offer a few to other enthusiasts. It is being offered through eBay or by contacting me directly. I don't know if there is a market for this sort of thing and any suggestions would be deeply appreciated. Thank you.

bob carnie
9-Jan-2012, 08:36
I use 250 w bulbs for mine, heads are rated for 150w, but I like the extra strength .
How much power would your system pump out compared to a standard 150w.
is it more or less??
Looks pretty slick.

bob carnie
9-Jan-2012, 08:38
Also do you use the filters and drawers exactly the same?
What grade would you consider the LED light without filters on a normal VC paper?

cardiomac
9-Jan-2012, 08:46
Thanks for the compliment. I was using a 150 watt bulb in my D2 which puts out about 2300 lumens. My LED head puts out only about 550 lumens but the exposure times are about the same. I think this is because the LED light is directional whereas the bulb is not, so much of the light output of a bulb never makes it to the film. Also, the LED's are brighter in the blue-green region of the spectrum where paper is sensitive. In practice, the LED's function much like a 150 watt incandescent bulb but without the drawbacks.

cardiomac
9-Jan-2012, 08:57
The filter drawer works normally except you don't have to worry about the filters melting during prolonged exposures. On Ilford MGIV in Dektol with no filter, I get about 8 steps on a Stouffer 21 step wedge which is the same as with a No. 2 Ilford filter. That translates to an ISO range of about 110, or a soft Grade 2 contrast.

Steve Smith
9-Jan-2012, 09:09
Is this just white LEDs? I have made an LED source for my enlarger using red, green and blue LEDs but I was thinking about trying a white LED source.


Steve.

cardiomac
9-Jan-2012, 09:19
These Cree light engines combine red-poor "white" LED's with red LED's to balance the spectrum. In an enlarger, the red light doesn't contribute to the exposure but it does make the image easier to see with the eye. I tried years ago to make a variable contrast light source using individually controllable blue and green LED's. Unfortunately, the blue LED's were not blue enough to get hard contrast prints so I abandoned the project after many, many hours spent on it.

Sal Santamaura
9-Jan-2012, 09:45
How even is illumination at the easel, i.e. difference in stops from center to corner?

cardiomac
9-Jan-2012, 10:06
Zero to less than a quarter stop. This was the biggest challenge in designing the lamp. Many hours were spent testing various reflector/diffuser combinations until I got one that worked perfectly. One of the key discoveries was that the lens needs to be curved to work properly with the condenser lenses on the enlarger. Another technique I used is to combine diffusive and reflective surfaces within the lamp to create an even light field at the lens surface. The evenness of illumination at the easel is directly proportional to the evenness of illumination at the lens surface. Also, note that the active area of the lamp lens is only the center 3 inches, not the entire surface. This mimics the geometry of an incandescent lamp and helps reduce stray light which "softens" the print.

bob carnie
9-Jan-2012, 10:34
Well I am really impressed and would like to know the price of one of these suckers.

I imagine the light falling on the easel is a bit softer than the tungsten bulb Y/N?
How long or how many exposures do you figure as compared to a 150w?

Zero to less than a quarter stop. This was the biggest challenge in designing the lamp. Many hours were spent testing various reflector/diffuser combinations until I got one that worked perfectly. One of the key discoveries was that the lens needs to be curved to work properly with the condenser lenses on the enlarger. Another technique I used is to combine diffusive and reflective surfaces within the lamp to create an even light field at the lens surface. The evenness of illumination at the easel is directly proportional to the evenness of illumination at the lens surface. Also, note that the active area of the lamp lens is only the center 3 inches, not the entire surface. This mimics the geometry of an incandescent lamp and helps reduce stray light which "softens" the print.

Sal Santamaura
9-Jan-2012, 11:17
...would like to know the price of one of these suckers...How long or how many exposures do you figure...http://www.ebay.com/itm/LED-Lamp-House-Omega-Variable-Condenser-D2-D3-D5-D6-Enlargers-/120840687166?pt=LH_DefaultDomain_0&hash=item1c22aa8e3e

Price seems very reasonable for what's apparently gone into it. Rated life of the light engine is quoted as 35,000 hours.

bob carnie
9-Jan-2012, 11:30
I am going to save my pennies and give this item a go. Who would have someone would take the time to make such an interesting unit for equipment so dear to me.


http://www.ebay.com/itm/LED-Lamp-House-Omega-Variable-Condenser-D2-D3-D5-D6-Enlargers-/120840687166?pt=LH_DefaultDomain_0&hash=item1c22aa8e3e

Price seems very reasonable for what's apparently gone into it. Rated life of the light engine is quoted as 35,000 hours.

ic-racer
9-Jan-2012, 12:18
This is a LED lamp for a condenser head, you still need the condensers, right? Or does this replace the condensers like an Aristo head?

If this is a LED lamp for a condenser head, you may, or may not know that the big-bulb incandescent lamps for the Durst 8x10 condenser heads are no longer available. This type of setup may be beneficial to those folks. I believe the 8x10 condenser heads need at least a 3" frosted illuminated circle to project an even image with the condensers. http://www.largeformatphotography.info/forum/showthread.php?t=74895&page=3

cardiomac
9-Jan-2012, 13:03
This just replaces the incandescent lamp house. You still need the condensers. That was part of the idea - create a cold light that preserves the features of a condenser head with its sharpness and accentuation of film grain.

With respect to the Durst dilemma, there are Cree light engines available in both American and European voltage versions that would be a good start for anyone who wants to try to make one. The LMR4 has a 4 inch aperture and would be a good choice.http://www.cree.com/products/modules_lmr4.asp
You may have to modify the diffuser to get the evenness of light you need as well as create some sort of housing to fit on the Durst. These modules are very reasonably priced. There is a youtube video showing some of the possibilities. http://www.youtube.com/watch?v=fz7Pl-zimRI



This is a LED lamp for a condenser head, you still need the condensers, right? Or does this replace the condensers like an Aristo head?

If this is a LED lamp for a condenser head, you may, or may not know that the big-bulb incandescent lamps for the Durst 8x10 condenser heads are no longer available. This type of setup may be beneficial to those folks. I believe the 8x10 condenser heads need at least a 3" frosted illuminated circle to project an even image with the condensers. http://www.largeformatphotography.info/forum/showthread.php?t=74895&page=3

cardiomac
10-Jan-2012, 05:13
Just wanted everyone to know that I have dropped the price on the LED lamp house to just cover my expenses and a little for the time it takes me to make it. This is a product that I think many people in this community would benefit from and I would like to make it as affordable as possible. I have enough parts to make three of them. Whether there will be any more depends on the reception these first three get.

Peter De Smidt
12-Jan-2012, 16:12
That looks very nice. Good work! If I had an Omega, I'd get one for sure.

Sal Santamaura
12-Jan-2012, 20:56
...I have enough parts to make three of them. Whether there will be any more depends on the reception these first three get.The eBay listing now shows "ended," so I assume they got a good reception. :)

ROL
13-Jan-2012, 17:58
I have an old D5 lying around, but am only shooting 5x7 these days. Any chance the light source could cover 5x7?

cardiomac
14-Jan-2012, 05:28
Since posting these for sale I changed the paint to a black wrinkle finish that matches the original finish on the Omega. I'll post a picture when I get to a computer ( I'm doing this on my phone) but it looks really nice. So I sold the original one (thanks!) and next I'm going to post the new ones in a new eBay listing.


The eBay listing now shows "ended," so I assume they got a good reception. :)

cardiomac
14-Jan-2012, 06:44
No, this lamp has an active light zone that occupies only the central 3 inches of its lens. This was done to match the light source to the condensers built into the enlarger. As far as I know, most 5x7 and 8x10 enlargers are of the diffusion type.


I have an old D5 lying around, but am only shooting 5x7 these days. Any chance the light source could cover 5x7?

cardiomac
14-Jan-2012, 16:01
Here is the LED Lamp House with the new wrinkle paint.

jon.oman
14-Jan-2012, 19:30
I would love to buy one of these, but I'm currently broke!

Well, I'm always broke, but I just bought frames and matting for 30 prints......

Jon Shiu
14-Jan-2012, 19:49
Here is the LED Lamp House with the new wrinkle paint.

Very cool product. I would buy one also if I had the money.

Jon

jeroldharter
15-Jan-2012, 17:50
Great work. I bet you could sell a lot of them if you adapted them to Beseler also.

It would be great if someone could assemble an array of 4-5 modules as a replacement for an Aristo 8x10 light source.

cardiomac
15-Jan-2012, 20:51
Great work. I bet you could sell a lot of them if you adapted them to Beseler also.

I'll see if I can scrounge up a Besseler enlarger and see what I can do. Do many people use the condenser heads, do you suppose?

jeroldharter
15-Jan-2012, 20:54
I'll see if I can scrounge up a Besseler enlarger and see what I can do. Do many people use the condenser heads, do you suppose?

I was thinking of a replacement for a cold light or Dichro 45S head rather than a condenser.

Curt
16-Jan-2012, 03:24
I was thinking of a replacement for a cold light or Dichro 45S head rather than a condenser.

Cold light to be sure. Or diffusion / diffused light.

cardiomac
16-Jan-2012, 09:29
I was thinking of a replacement for a cold light or Dichro 45S head rather than a condenser.

Seems like most people like a diffusion enlarger head. With the Aristo head, you use below-the-lens VC filters, right?

Peter De Smidt
16-Jan-2012, 09:50
Seems like most people like a diffusion enlarger head. With the Aristo head, you use below-the-lens VC filters, right?

Yep.

Richard M. Coda
16-Jan-2012, 09:54
Looks cool... like Iron Man. If I plug one into my chest can I fly? :) Job well done!

Jon Shiu
16-Jan-2012, 10:07
I'll see if I can scrounge up a Besseler enlarger and see what I can do. Do many people use the condenser heads, do you suppose?

The Beseler condenser head is by far the most popular, as far as numbers made and use in schools. I generally prefer the condenser to a cold light or diffusion head for print quality.

Jon

Roger Cole
16-Jan-2012, 10:41
Well the one eBay listing has expired and the seller doesn't show any other auctions. Are these still available?

I too would prefer one the functioned as a diffusion head without the condensers, but I'd probably buy one of these as-is. I have an Omega so not looking for a Bessler model.

I tried a 150w bulb and found it too bright for my usual printing so I went back to the 75W. Some of y'all must be making some seriously dense negatives or you like very short printing times. ;) No matter - I can always add some neutral density to the filter drawer and it could be nice to have the extra speed when needed, making large prints from dense negatives or such.

This looks like a really great product.

cardiomac
16-Jan-2012, 16:32
The Beseler condenser head is by far the most popular, as far as numbers made and use in schools. I generally prefer the condenser to a cold light or diffusion head for print quality.

Jon

Does the condenser head have a slot for VC filters?

cardiomac
16-Jan-2012, 16:41
Well the one eBay listing has expired and the seller doesn't show any other auctions. Are these still available?

I too would prefer one the functioned as a diffusion head without the condensers, but I'd probably buy one of these as-is. I have an Omega so not looking for a Bessler model.

I tried a 150w bulb and found it too bright for my usual printing so I went back to the 75W. Some of y'all must be making some seriously dense negatives or you like very short printing times. ;) No matter - I can always add some neutral density to the filter drawer and it could be nice to have the extra speed when needed, making large prints from dense negatives or such.

This looks like a really great product.

Thanks for the compliment. They are still available. One has been sold and I have another made and ready to sell. I will be making at least two more and more than that if there is demand. I'll be putting them up on the eBay site as well as the For Sale forum here. Feel free to email me directly as well.

Roger Cole
19-Mar-2012, 16:44
Well I did buy one of his early units. Here's a duplicate of what I just posted about it on APUG:

I have had a chance to do a fair amount of printing with my LED lamphouse now. The results have been great. I can tell no difference in evenness or contrast between the LED lamphouse and the incandescent one. Printing speed is just about squarely in between that of using a 75W #211 bulb in the incandescent and using a 150W #212. In other words, it's faster than the 75W, but slower than the 150W. It's fine for the vast majority of my negatives.

I have not tried the extreme ends of the contrast filtration scales yet. I was going to do that, but Cemil graciously offered some free upgrades of my head (which is one of the first prototype units) to his current standard, and I just shipped it back to him today. I haven't had a chance to print in a while as I've been quite busy (and probably won't again until April. Should have a lot more time after that, though.)

But the last time I printed I did finally get around to making some test prints with no negatives to compare evenness.

These are prints with no negative in the carrier, using a 6x9 cm carrier, 100mm Componon-S enlarging lens, on my Omega D2/II-V (it's a D2 chassis on which someone has mounted the variable condenser head.) I used the grade 2.5 MG filter from a brand new set of filters. I use the 6"x6" above the lens filters and just lay them atop the lower condenser, which works fine. The lens was stopped down all the way to give a somewhat manageable albeit still short exposure time, which probably explains the in-focus splotches and dust that were apparently on the bottom of the upper condenser and which I immediately cleaned off, but also had not noticed on any of my prints, as I don't normally expose negatives at f/32.

The densities are obviously not exactly matched, but I didn't care to spend more paper getting them closer. You can match in PS if you want and still compare evenness.

These show why I can tell no difference between prints made with the two lamphouses. Some edge fall off is normal but on both I see a bit more than I thought it was. I normally edge burn all my final prints by about 15% of the base exposure time. I may extend that a bit, and maybe burn a little farther in from the edges than I have been particularly on the long axis, though I've not noticed any problems or unevenness in my prints. This sort of test will show tiny variations.

Standard incandescent lamphouse:

http://home.comcast.net/~ragnar93/Temp/IncandescentLamphouse1.jpg

LED lamphouse:

http://home.comcast.net/~ragnar93/Temp/LED_Lamphouse1.jpg

I'm quite pleased with the unit. It's nice to leave the light on as long as you like for focusing and cropping without worrying about negative popping or lamp life and to make exposures as long as you like with the same lack of concerns. It's also nice to use it for checking the negative carefully and repeatedly for dust without concern for lamp life.

Mine being a very early unit, it has a two prong plug and cord. Cemil is graciously replacing the cord for me with a three prong grounded cord and plug. This will be better, though I was not concerned with it personally as the way my darkroom is laid out there isn't really any realistic chance of it falling into liquid or the like. It also may improve the one very minor drawback I've found - it generates a fair amount of radio hash and interferes with my FM boom box in the darkroom. Most folks who listen to music while printing may be 100% digital anyway. In my case, I use my iPhone just outside the darkroom or the computer upstairs to stream Pandora or, most often, WWOZ from New Orleans, with the output going into an FM modulator which I pick up on the (all lights taped over) boom box inside. When this unit is on it generates a fair amount of hash, but I can live with that as it is, of course, only when the enlarger is on. The grounded cord may help this. I can't just use the iPhone inside because I can't turn on airplane mode and still stream, and there would be the chance of getting a call or text and a very unwelcome blast of light at the wrong time.

Pros: Very well made unit that looks like it came out of a factory. Actually, strike that - it looks like it came out of a factory perhaps 30-40 years ago when they made stuff more solidly. Works well with very even illumination, or at least comparable to the stock incandescent lamphouse. I suspect what unevenness is present is due to the design of the condensers rather than the light source, since the two are so similar in evenness. I also suspect but have no tests to prove that both the spectrum and the light output of an incandescent bulb vary more over its life than this LED source will, so prints may be more easily repeatable from notes when made much after the initial prints and data. Much less heat generated and power used than the standard lamphouse.

Cons: Hmm, well, it generates some radio static. It probably isn't usable for color per our discussion [on APUG] though I haven't tried it, so if you print color with CP filters you may have to switch back to the standard lamphouse. This takes about 30 seconds if you take your time, 15 if you hurry. Honestly that's all I can think of.