Let’s start a separate thread to document exposure unit/lamp specs and performance. I’m getting my NuArc 26-1KS setup and will be able to report back some real world performance very soon, but thought I would go ahead and share these details.
The main difference between a 26-1K and a 26-1KS is the lamp. 26-1k uses a mercury vapor lamp, the 26-1ks a metal halide lamp. I don’ have the spec on the mercury vapor lamp, but do know the metal halide lamp part number is NP80. Attached is the spectral response info. Looks like it’s main output is between 350nm and 400nm.
As soon as I have made some calibration prints I’ll report back on how the mater curve works with this setup.
Since Gilles has mentioned “doped” metal halide lamps, I’m guessing some folks may be wondering just what that means, and while some may wonder what is the difference between metal halide and mercury vapor.[attachment file=“26311”]
The simple answer to the second question is that metal halide is a “new and improved” variety mercury vapor. Metal halide lamps are mercury vapor lamps doped (or dosed in some of the literature) with metal halide additives that modify the spectrum of the output. Gallium “doped” lamps have peak output in the 400-420nm range. I think it is safe to say that the Olec L900/L1250 are gallium doped, as are Gilles’s and Rafael’s based on the spectral charts they posted. [attachment file=26312]
The iron doped lamps include the Olec L1261/L1281. [attachment file=26313]
I’m guessing that the Olec L902/L1252/L1282 might be a combination.
If you are using a plateburner and don’t know what kind of lamp you have, one way to make a good guess is from the color of the light. A slight greenish hue indicates that it is probably plain mercury vapor. A blueish hue indicates iron-doped. And a purpleish hue indicates gallium-doped. At least that’s what I read somewhere.
I installed the Ushio MHL 1000/1 metal halide lamp in my Nuarc 26-1K. Ushio says the spectral response curve is 350-370 nm (however another Ushio site says the spectral response is 400 - 450 nm: http://www.ushio.com/products/graphic-arts/metal-halide-lamps/mhl-metal-halide.php I have an email into them to clarify and will update this post when I hear back from Ushio.)
Hey Michael - It looks to me like the Bulb Connection site and the Ushio site both say 350-370nm for the MHL 1000/1. I do see a MHL 1000 on the Ushio site that is 400-450nm. Or is there a 2nd Ushio site?
Cool that there is a bulb for the Nuarc that doesn’t cost a couple hundred $s.
From the Ushio page which shows the 400-450 nm spec there is a link which opens up the catalog pages for their “graphics art” bulbs. The catalog pages were the ones I uploaded previously; this shows the 350-370 nm spec.
I did get a quick reply back from Ushio customer service. The tech has forwarded my question onto the product manager. So we’ll see if I get an answer back soon.
Michael - The Ushio page says the MHL 1000/1 (11th down on the list) is 350-370nm. There is also a MHL 1000 (7th on the list) that is 400-450nm but that is not the same bulb. Look again and check the order code 5000062.
You are indeed correct! Thanks for that! Not reading the fine print. It’s really Ushio’s fault for having part numbers so close together! I won’t be signing any contracts in the near future! ;-).
“So I’d say that most (ca. 90%) of the action in Pt/Pd printing occurs within the wavelength range 320-430 nm. The yields of Pt and Pd peak around 360-370 nm.
You may quote me on that.”
