First Laser photo (445 "1 watt" with 3X beam expander

[Pelagius]

Hi all,

I have one of those common 445 nm "Gatling lasers"- and I ordered a Sanwu 3X Beam Expander for it-which works perfectly. The only issue is that the host starts to get warm after a minute-or less. (I shut it off for awhile-having read the forum on the subject)

I am focusing it on a matte dark grey rock-which smokes when the beam hits it.
Here is my first shot- I need practice. I'm using a DSLR.
I have "googles"- Eagle 6 OD 190-540 nm goggles from Gary at Survival Laser.
Anyone have any suggestions for photo set up?
Thanks!
Eric

 

[paul1598419]

The gattling host is about the worst heat sink you can get for any laser diode above 400 mW. It will likely heat up regardless of the BE, but might heat up more quickly with it on. If you are trying to take photos on a 1 watt laser, don't do it in the dark. The only light source is the laser and it will over drive the sensor in your camera.

 

[Pelagius]

Hi Paul,
Thanks for the tip! I will likely replace the Gatling 445 with a better built laser-from Sanwu. Something with a better heat sink. MAybe one of their guardians-also I like the look of 473 nm's so I'd probably go that route.
I had some light coming in-thanks for the warning. I suppose I could get a fog machine to make it easier to see with more ambient light.

The gattling host is about the worst heat sink you can get for any laser diode above 400 mW. It will likely heat up regardless of the BE, but might heat up more quickly with it on. If you are trying to take photos on a 1 watt laser, don't do it in the dark. The only light source is the laser and it will over drive the sensor in your camera.

 

[paul1598419]

I don't have any Sanwus and many people here like them a lot, but what I dislike about them is their use of steel as a host. It has terrible thermal conductivity properties, but they use either a copper or brass heat sink inside the steel host. Since steel is so bad thermally, the heat sink cannot release its heat to the air outside. I use the same diodes they do, but build all my own pointers, so they are made of copper or aluminum, which have very good thermal conductivity. I can also build a laser for much less than they charge for the ones they sell.

I do like the price on their 3.3X beam expander and plan on buying one in the near future, but their lasers......no. Funny thing is that many people like the steel hosts because they are heavy and feel good in your hand. But, it is really a bad material to make a laser host out of.

 

[steve001]

I don't have any Sanwus and many people here like them a lot, but what I dislike about them is their use of steel as a host. It has terrible thermal conductivity properties, but they use either a copper or brass heat sink inside the steel host. Since steel is so bad thermally, the heat sink cannot release its heat to the air outside. I use the same diodes they do, but build all my own pointers, so they are made of copper or aluminum, which have very good thermal conductivity. I can also build a laser for much less than they charge for the ones they sell.

I do like the price on their 3.3X beam expander and plan on buying one in the near future, but their lasers......no. Funny thing is that many people like the steel hosts because they are heavy and feel good in your hand. But, it is really a bad material to make a laser host out of.

If you build your own lasers why not build a beam expander?

 

[Alaskan]

$ Cheaper to buy already made and less hassle is why for me, but I intend on having some big collimator hosts machined for me by Trịnh Hồng Phước. Due to having some 3.35 inch dia. PCX lenses, that kind of collimator is cheaper to build yourself, than buy, if you find a nice lens cheap on ebay, which I did.

 

[steve001]

$ Cheaper to buy already made and less hassle is why for me, but I intend on having some big collimator hosts machined for me by Trịnh Hồng Phước. Due to having some 3.35 inch dia. PCX lenses, that kind of collimator is cheaper to build yourself, than buy, if you find a nice lens cheap on ebay, which I did.

Or build threaded adapter(s) that would allow one to use expanders of any make. What's the focal length of that 3.35 pcx lens?

 

[Gazen]

I don't have any Sanwus and many people here like them a lot, but what I dislike about them is their use of steel as a host. It has terrible thermal conductivity properties, but they use either a copper or brass heat sink inside the steel host. Since steel is so bad thermally, the heat sink cannot release its heat to the air outside. I use the same diodes they do, but build all my own pointers, so they are made of copper or aluminum, which have very good thermal conductivity. I can also build a laser for much less than they charge for the ones they sell.

I do like the price on their 3.3X beam expander and plan on buying one in the near future, but their lasers......no. Funny thing is that many people like the steel hosts because they are heavy and feel good in your hand. But, it is really a bad material to make a laser host out of.

Other than their striker and pocket series, their hosts use a nickel-copper alloy rather than steel.

I agree with you on the prices, some of their items are decently priced but many are expensive for the diode. Their host quality is hard to beat though.

 

[paul1598419]

I have not thought about trying to build a beam expander. Mostly, because I don't have the lenses for even one. The $55.00 price for the 3.3X expander is hard to beat, but I understand it has a small input lens, so one needs to get it close to avoid clipping if it is the only optical correction being used. I am hoping the my cyl lens corrected 44 build will be tight enough to get into this BE with no problems. Time will tell. :yh:

 

[Alaskan]

Paul, I've been remiss on getting a 3.35 inch lens to you, that seller never came through, so will do from here. These lenses have a FL of just under 4 inches.

 

[paul1598419]

Thank you, Chris. It would be a nice lens for a BE. I do have a few large lenses from the wandering box of laser related items started by Jmillerdoc. Haven't pulled them out in a long time. Will have to give them another look.

 

[steve001]

I have not thought about trying to build a beam expander. Mostly, because I don't have the lenses for even one. The $55.00 price for the 3.3X expander is hard to beat, but I understand it has a small input lens, so one needs to get it close to avoid clipping if it is the only optical correction being used. I am hoping the my cyl lens corrected 44 build will be tight enough to get into this BE with no problems. Time will tell. :yh:

Keplerian expanders are suitable for low output lasers. I suspect you would not build that type. Galilean type are preferred for all power outputs but the problem as you noted is clipping but the output lens could clip too depending how greatly the input lens diverges the beam. Your cylindrical lens correction is a good solution.

 

[paul1598419]

I suppose I could build a Keplerian BE as I am familiar with them, but it is likely I will have lenses for the Galilean one before I get ones for the other. I do plan on buying the Sanwu 3.3X BE first as it is a reasonable price and will fit the host without any tinkering.