My 477nm and 502nm builds.

[paul1598419]

Thanks, Peter. Yeah, I live in an older mansion in north Tacoma. The ceilings are 12 feet and that is stained glass in the door. It is hard to heat this big old place in the winter, but I do air condition it in the summer. Most people here don't have A/C and get by with a fan or two. Right now it is 36 degrees outside and a bit cold for this old body. I still use the walker, but much less than I used to.

 

[Atomicrox]

Great builds as always!

I'm finishing up my 477nm and I'm curious as to how you managed to focus with the acrylic lens. My barrel is so short it has to be inserted almost all the way in for infinity focus. Not practical at all. I'm leaving the S1 lens for now (does about 125mW @ 260mA with that), but the artifacts are horrible.

 

[paul1598419]

Great builds as always!

I'm finishing up my 477nm and I'm curious as to how you managed to focus with the acrylic lens. My barrel is so short it has to be inserted almost all the way in for infinity focus. Not practical at all. I'm leaving the S1 lens for now (does about 125mW @ 260mA with that), but the artifacts are horrible.

It's quite simple, actually. I use fingernail polish on the rim of the focus knob and screw the lens housing in one turn only. Let it set up for about an hour and it will hold it in place just fine. I use fingernail polish because if you make a mistake it is easily removed with acetone......then you can start over. Stay away from the extra heavy springs as they put too much tension on the focus ring.

 

[Atomicrox]

That's a very good idea, pity I can't rep you.

 

[paul1598419]

That's okay. I can rep you instead.

 

[Lifetime17]

Hi Paul,
I try to thread a minimal amount of threads in my adapters so folks don't need teflon or some other means to keep it up front , I will try only about 3 threads now so its just a full turn and a half.

Rich

 

[paul1598419]

That is a great idea, Rich. The acrylic lenses aren't the only ones that come up short so I have been using fingernail polish for years to lock the lens housings down as soon as the threads of the focus ring/knob grab hold of it. You do have to use the old type springs as the higher tension ones put too much pressure on the lens housings and will break the polish loose. It's much better than using epoxy as acetone can remove any trace of it if you make a mistake and have to start over.

 

[steve001]

That is a great idea, Rich. The acrylic lenses aren't the only ones that come up short so I have been using fingernail polish for years to lock the lens housings down as soon as the threads of the focus ring/knob grab hold of it. You do have to use the old type springs as the higher tension ones put too much pressure on the lens housings and will break the polish loose. It's much better than using epoxy as acetone can remove any trace of it if you make a mistake and have to start over.

Beacon 527 cement works very well. I've used it in the past to secure lenses in place. Cleanup with acetone before it sets. After it sets it can be peeled away without leaving residue. Remains flexible. Available in craft stores.

Nice colors.

 

[paul1598419]

I've tried model cement which sounds similar to the Beacon stuff. It remains rubbery and doesn't seem to hold as well as nail polish, which dries hard. If you are trying to bond the lens housing where it can't be broken loose, two part epoxy is the only thing I've found that will do that. If you make a mistake with it, you are screwed, though. You'll never get it off completely........even before it sets.

 

[steve001]

I've tried model cement which sounds similar to the Beacon stuff. It remains rubbery and doesn't seem to hold as well as nail polish, which dries hard. If you are trying to bond the lens housing where it can't be broken loose, two part epoxy is the only thing I've found that will do that. If you make a mistake with it, you are screwed, though. You'll never get it off completely........even before it sets.

Beacon isn't rubbery. It sets up firmly but remains flexible. It's a one part not a two part material. You can read more about it online. Like I said, I found it useful for holding lenses in place and easy to remove by peeling away. Fingernail polish always requires a solvent.

 

[paul1598419]

Beacon isn't rubbery. It sets up firmly but remains flexible. It's a one part not a two part material. You can read more about it online. Like I said, I found it useful for holding lenses in place and easy to remove by peeling away. Fingernail polish always requires a solvent.

Interesting. It dries hard but peels off too? Does it peel off the threads on the lens housing as well? It is the grooves that seem to be the hardest part to remove glue from. Have you ever tried nail polish? It really does work well for this application. I used to use it in place of "Loctite" when working with set screws that needed it.

 

[RedCowboy]

It's interesting how the backlighting changes the perception of the color, at least as the camera sees it, but I know a blue looking 445 suddenly appears purple when placed next to 470, so our perception seems to change as well.

 

[paul1598419]

That is a difference of 25nm. You should see how blue 502nm looks next to 510nm. And the 510nm looks yellow next to the 502nm. That is only a difference of 8nm. Must sit in a particularly differential set of wavelengths.

 

[RedCowboy]

It's amazing that the light sensing nerves " cones for color " on our retinas can tell the difference, I have read that we can detect a single photon of light in darkness (Rods) .

I also have read that our cones are coated with pigment, so is it a measure of the level of stimulation of RGB that our occipital lobe uses to determine color ?

This could explain why our perception changes when other light is present, I suppose to really see the color we should observe it in a dark room with no other light sources other than the nm of light we want to see for it's natural presentation.

 

[steve001]

Interesting. It dries hard but peels off too? Does it peel off the threads on the lens housing as well? It is the grooves that seem to be the hardest part to remove glue from. Have you ever tried nail polish? It really does work well for this application. I used to use it in place of "Loctite" when working with set screws that needed it.

Careful I said it dries to firm. Practically if you have a blob and let it dry according to directions you could indent it with a fingernail. Yes, it remains flexible. To remove it I would use a pin. I like the nail polish use but using acetone one could still leave polish residue.
I have a Nova Laser green laser and would swap out lenses. That's how I discovered it's usefulness. It should peel off threading just like glass since that type of surface is not porous. I don't feel this solvent based cement would be appropriate for acrylic lenses.

 

[paul1598419]

Careful I said it dries to firm. Practically if you have a blob and let it dry according to directions you could indent it with a fingernail. Yes, it remains flexible. To remove it I would use a pin. I like the nail polish use but using acetone one could still leave polish residue.
I have a Nova Laser green laser and would swap out lenses. That's how I discovered it's usefulness. It should peel off threading just like glass since that type of surface is not porous. I don't feel this solvent based cement would be appropriate for acrylic lenses.

I assure you that using acetone to remove nail polish removes all traces of the polish. I put the acetone on a cloth and use the cloth to remove it with. You do need to keep it away from the acrylic lens as that would damage the lens. It is quite easily done with a cloth. I have had several occasions where I needed to remove nail polish when I didn't allow enough time for it to set completely and all traces of it came off allowing me to start over and get it right. I have several builds with these short acrylic lens housings held in place with fingernail polish and have been holding up well for years. It is easy and relatively fool proof and once done holds up for many times of refocusing to infinity.