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Ulophot
3-Jan-2023, 21:03
Even though I’m still waiting to finish using Nigel’s Excel macro to even the light out, I’m excited to show this new LED head on my D2, built by a friend up the lane, for those who haven’t seen my other posts.
It uses a 256-LED RGB panel, which I have balanced to yield a Gr. 2 with no filtration or with the No. 2 Ilford filter. It’s designed for this white light application only; it’s all I need in that respect.

The housing of the head and controller are 3D printed. The controller is an Arduino chip running some C++ code -- out of my league. Since the housing is so light-weight, I have hung lead weights from the back of the carriage to counterbalance the strength of the carriage springs.

The computer fan in the top is relatively low RPM, vibrationless, and very quiet indeed. Vents in the sides of the housing top component increase air flow.
The 6”-square panel’s light passes through an 1/8”-thick white acrylic panel 4.5 x 5.5.

The controller is simple but functional. Each knob has two functions. The left sets the exposure time in hundredths of a second. Press/release it and it adjusts R, G, B, and overall intensity (I) individually (successive presses for each, then it returns to exposure time). Press the right knob to turn the light on for focusing. Press again to turn it off. In the off position, turning it adjusts the dry-down percentage from 0% to 15%.

I use a foot switch to activate timed exposure.

It’s not as bright as others have built with single-LED arrays, but it’s sufficient, and I hope to increase the output overall as I balance the light a bit from the way it is being done now. Evenness will also improve a bit whenever I can afford a 150mm lens to replace my 135.

Many mistakes and printing problems along the way added to the cost, but materials to build a replica would probably total less than $160. I was hoping my friend would offer to make some additional ones for interested folks for a modest price, but right now he’s involved with something else for the meantime. I continue to hope that others with the skills and equipment will do something similar. Intrepid has ventured in that direction; perhaps it will inspire others.

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Ben Calwell
4-Jan-2023, 08:33
It looks great, Philip. I wish I had a “friend up the lane” who could make one for me. I use a D2 outfitted with an old Aristo cold light head. I have to use a yellow filter to tame the blue light coming out of it. I once had the hare-brained idea — expressed on this forum — to somehow retro-fit Intrepid’s LED enlarger head onto my D2. The idea was met with the sound of crickets, which I took to mean that it was, in fact, a hare-brained idea politely dismissed on this forum by those who are light years ahead of me when it comes to feats of engineering and DIY know-how. Anyway, I digress. I would buy what you have if they ever become available.

John Layton
4-Jan-2023, 09:08
Ben...retrofitting the Intrepid 4x5 LED would likely be possible - and perhaps as simple as placing a negative into the holder, then clamping this shut either with a rubber band or clothespin, placing this on the enlarger negative holder stage, then simply placing the Intrepid lamp atop the negative holder.

If I were you...I'd contact Intrepid for dimensional specifications of their LED VC light source. Who knows...perhaps you might be able to integrate this into the existing D-2 lamp house lifting mechanism?

Doremus Scudder
4-Jan-2023, 14:07
... I once had the hare-brained idea ...

Sure nice to see someone who can correctly spell "hare-brained." :)

koraks
4-Jan-2023, 14:57
Ben...retrofitting the Intrepid 4x5 LED would likely be possible -
It almost certainly would, indeed. I don't see why it wouldn't; it's just a matter of making it fit mechanically and perhaps adjust the distance to the negative stage a bit to obtain good evenness.

Ulophot, yours looks really nice �� I bet it took eons to print those enclosures!

Ulophot
4-Jan-2023, 19:18
koraks (any relation to kodaks?), this is v2. V1 also had two components, "stacked," but the top one went from square at bottom and up a few inches, then changed slowly to round and attached to the upper stage of the D2 housing, the one just below the lamp housing, using the three screws that otherwise hold the round, aluminum condenser/coldlight sleeve. He surprised me with this one.

As for printing time, he said the housing can print over night, or maybe each half of it. I don't know about the struts on the sides that attach to the lifting arms. He said that the four original screws in the arms have different threads, which is odd. One is an extremely tight fit, another needs a "thread booster" of wire to screw in. I got the enlarger used, decades ago, so perhaps he's right, but I was surprised by this.

koraks
5-Jan-2023, 01:00
koraks (any relation to kodaks?)
No, none; there's no exciting backstory to the name btw ;)


> he said the housing can print over night
Yeah, that sounds reasonable. I've been printing quite a few odds and ends lately and my main qualm with the whole thing is that it's so darn slow. Since my printer is within hearing distance of our bedroom, I never print when we sleep. Or, I should say: it's EITHER print, OR sleep LOL!

Ulophot
5-Jan-2023, 10:38
He had a devil of a time with printing. First he burned out a print head with a carbon fiber mixture filament. Further on, another filament was melting before setting. Later, he was finding repeated failures in the morning, which he finally traced to a coding error from the manufacturer that was not lifting the head properly between repositionings. He fixed the code and I think all is well now. I bought him an extra roll of filament.

Tin Can
5-Jan-2023, 12:13
I know we all love DIY

Intrepid was just mentioned again in this thread

They 3d print the lamp house, controller box and knobs

It is designed to fit where the Intrepid GG fits

Some of you should look at what they offer

I am very happy with mine

https://intrepidcamera.co.uk/blogs/guides

Kerosene Hat
10-Jan-2023, 17:32
I know we all love DIY

Intrepid was just mentioned again in this thread

They 3d print the lamp house, controller box and knobs

It is designed to fit where the Intrepid GG fits

Some of you should look at what they offer

I am very happy with mine

https://intrepidcamera.co.uk/blogs/guides

I emailed Intrepid and asked if they'd do a custom project for a similar 8x10 enlarger. Resounding, "no"...HOWEVER...

They may be planning to launch a productized 810 enlarger later this year, hmm...

nolindan
10-Jan-2023, 17:46
Unhooking one of the two 'counter weight' springs might remove the need for any lead weights.