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For scenery typically you want a standard lens (focal length of about ~50 to ~58 mm => field of view of ~40° to ~50°), plus a wide angle lens. I also like the very wide angle 'Fish Eye' lenses, but when you go that wide distortion is inevitable so yeah. I would buy old manual lenses, they are...

These are all auto, I would only buy quality manual lenses.

once you run a current through it, it's "collisions of the second kind" that excites all these excited states, it is one of them (helium metastable) that lives a long time before it decays.

I threw my hat in the ring, but sadly the auction you mentioned got sniped. I wanted it for laboratories but some hobbyists and new agey/steampunk collectors tend to bid very high so no bargain is found.

The original ruby laser didn't have separate mirrors, ends of the rod were silvered (one only partially). With the flash light it would oscillate in a single pulse and shut itself down and then u have to switch it on and a few seconds later switch it on. No wonder it is no longer being used...

Actually it is just the ebay sellers which sell the tubes at such a high price. If you go to some countries of the ex-shorawi there are surplus places where you can get these tubes at dirt cheap. The down side with nixies, aside from their efficiency, is that they get cathode poisoning...

Sure, here is a close up of the label: Nop, there's just one white, a yellow, a green, and a violet loop (which I think has to be cut if want to defeat delay). So this is a 120 volt only?

Thanx a lot for all the responses. :yh: Lasersbee, it's a compact brick style PS. It operates from the 115 volt ac line, the output is 1800-2600 volts @ 6 mA. I've attached a photo. Pschlosser, not sure if that works, I think it's 230 V with respect to ground/zero voltage reference node...

I've got this HeNe power supply that runs off the mains. But the problem is it takes 115 Vac (designed for the US mains where you have 120 volts). Here in the southern hemisphere electricity is distributed as 50 Hz ac at ~230 V. I think the psu has some kind of rectifier to get dc, and then...

I kind of feel sorry for all of that technology with its beautiful physics, being used solely as a lamp. The whole point of a laser is the beautiful collimated pure frequency amplified beam it produces. What you see in the tube is the negative temperature medium and that orange–red colour...

That's a good link but there is not much info on the specification of individual power supplies. :thinking: This is a good one but it only works for the 6" tubes, if you look at the current and voltage rating. The seller doesn't ship to the southern hemisphere where I live. And the current...

But those power supplies are listed as having a lower limit of 1900 V. So if I use it on my laser then they are operating at ~30% less. Is that okay with the tube and the psu? :thinking: This other one also from MI is closer to my budget (but still ~20% less than the actual specs) : Meredith...

Hi guys! I am having a lot of trouble finding the correct power supply for this laser. It's a uniphase 8.5" red HeNe tube as seen in the pic below. According to the seller the operating current is 6.5 mA and the operating voltage is 1300 V (and maximum starting voltage is 10 KV DC). Does...

I must say your camera picked up the yellow more like fluorescent yellow of a highlighter pen, but in person 594 nm looks a lot warmer like a beautiful sunset yellow. Here are a few pics of my yeenee (yellow HeeNee) I didn't have a fog machine to properly enhance the beam, but still I think my...

I tried this once years ago using copper heat pipes. It didn't go so well (mainly because I didn't have access to lathe). There are already good hosts out there suitable for high powers, life is too short to create one from scratch.

Really love that ~611 nm Orange, they are incredibly rare to find at an affordable price. :) There is another orange HeNe line which is even more rare to find at ~604 nm (it's from the transition 3s2->2p7, whereas your one is down to 2p6). It fits right below that 594 nm yellow (2p8). Not sure...

I have a HeNe tube at 593.93 nm just like these Rigels and I bought it for $200. The coherence length and monochromaticity of these dpss lasers are much poorer than traditional lasers like HeNe because it's pumped by a diode with a cavity that is only a fraction of a millimeter long. And...

Most cameras tend to pick up 650 nm and longer waves as pink, and 635 nm as orange. But clearly that's NOT how these two colours look once we look at them with our eyes. The crystals are quartz most likely, maybe you should have used a more interesting crystal like calcite and see what comes out.

Hey, the second to last pic is not 100% clear but I think the mode pattern is either TEM_22 or TEM_33. :rolleyes: If the diameter of the discharge tube is a bit larger then it's probably intended to be multimode... though higher order TEM waves are much more academic and not too practical (since...

The electrode configuration is normal, many discharge tubes especially some older gas lasers looked like this. When you connected the power supply did you manage to get the plasma started inside the tubing? If so what colour was it? If you had the plasma going but no lasing, it could be the case...