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Sanwu Pocket 638

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Hey all, I'm about to pull the trigger on getting a Sanwu Pocket 638nm 300mw laser with a G7 lens. I've been researching for a couple of months now. I really want a red (or redish) laser primarily for star pointing. From what I've read, 300mw of 638 should do the trick anytime after dusk. Does that sound about right? I'm not really into burning, but would love a sharp, visible beam to pop into the sky.

I have a ~100mw 303 green laser from Sanwu that is perfect for star pointing. Love the crisp beam.

I was thinking about going for a higher power Bitlaser 750mw 638, but thought it might be too bright for my purposes. I have a 1w 445 laser from Eitan that is honestly too bright when I'm star pointing while using my telescope (not sure if that's just bad divergence or if it's just really bright - it lights up trees around me while I'm pointing. Love it for burning, but I don't do that much).

Do you think the 300mw from Sanwu would be good, or should I got with the higher power Bitlaser 638?

Thanks all! I've been creeping on these forums daily for a few months now. Thanks for all of your helpful thoughts and advice!
 

Sta

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The Sanwu 300 should be plenty bright! As an added upside, it will have a single mode diode - which means a much nicer, rounder beam, as opposed to the BitLasers 750mW, which has a multimode diode with a line-like beam.

It should also have excellent divergence (possibly <1mRad!)

You'll be very happy with it - even my 100mW 637 has a reasonably bright beam. 300mW should be enough to easily see from the side.
 
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Podo

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Thanks ,Sta

If the brightness of our 80mw green laser pointer is acceptable to you, 300mw of 638nm should be fine because it has a lower visibility compare to the green pointer.

Also, it has a wider beam making the beam much noticeable good for star pointing.
 
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Koff

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What? Is the 300mw 638nm single mode diode? I thought it was multimode. What diode is it?
 
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What a great response. I'm sold. Will be purchasing today or tomorrow. Thanks Sta and Podo for your sage thoughts! I'll leave a review when I get it. Super super excited about it.
 
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Hey there! I got my Sanwu Pocket 638 a few weeks ago with a G7 lens (and green safety glasses). I believe that it is multimode as the dot is actually a line and the beam is flat and expands over distance. It's a really sleek design and the host feels wonderful. It's so small. I got it to burn some paper, but haven't done much in the way of burning.

The beam is less bright than I had hoped it would be. I can see it ok on a moonless night, but have difficulty if there's much light outside/inside. Great for stargazing, just not quite as bright as I thought it might be.

There has been a weird thing that has happened in that regard though. I feel that the laser is brighter at times. The other night all of the lights were on in our living room and I could see the beam extremely well and my wife could too who was sitting parallel to it about 10 feet away. I'm not sure if I'm making that up or what. As I'm writing this I can barely see the beam unless I look at the laser from directly behind and that's on a fully charged battery. I've tried to figure out if I put it into Safety Mode on accident, but it's single mode and the 5 half clicks in 3 seconds doesn't seem to do much. Maybe it was just more humid or something at that time.

I got the pattern heads along with this purchase and can't figure out if they go on the Pocket laser or not. I haven't been able to find a way. But they screw perfectly into my other ~80mw green laser from Sanwu so that's perfect.

Anyway, it's a really solid feeling laser, the shipping/packaging was adequate, and it's a great leap into the 638 family for me. This is my second Sanwu experience and it's been great.

Anyway, I'll probably go for a Bitlaser 750mw or the Sanwu Guardian 638 next. I'll try and put some pictures up, but I couldn't figure that out the other night. We'll see if I can get some on here in the near future.
 

diachi

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Hey there! I got my Sanwu Pocket 638 a few weeks ago with a G7 lens (and green safety glasses). I believe that it is multimode as the dot is actually a line and the beam is flat and expands over distance. It's a really sleek design and the host feels wonderful. It's so small. I got it to burn some paper, but haven't done much in the way of burning.

The beam is less bright than I had hoped it would be. I can see it ok on a moonless night, but have difficulty if there's much light outside/inside. Great for stargazing, just not quite as bright as I thought it might be.

There has been a weird thing that has happened in that regard though. I feel that the laser is brighter at times. The other night all of the lights were on in our living room and I could see the beam extremely well and my wife could too who was sitting parallel to it about 10 feet away. I'm not sure if I'm making that up or what. As I'm writing this I can barely see the beam unless I look at the laser from directly behind and that's on a fully charged battery. I've tried to figure out if I put it into Safety Mode on accident, but it's single mode and the 5 half clicks in 3 seconds doesn't seem to do much. Maybe it was just more humid or something at that time.

I got the pattern heads along with this purchase and can't figure out if they go on the Pocket laser or not. I haven't been able to find a way. But they screw perfectly into my other ~80mw green laser from Sanwu so that's perfect.

Anyway, it's a really solid feeling laser, the shipping/packaging was adequate, and it's a great leap into the 638 family for me. This is my second Sanwu experience and it's been great.

Anyway, I'll probably go for a Bitlaser 750mw or the Sanwu Guardian 638 next. I'll try and put some pictures up, but I couldn't figure that out the other night. We'll see if I can get some on here in the near future.

Atmospheric conditions have a big impact on beam brightness, so that could explain the difference in brightness. I found that when someone was cooking downstairs in the house back in Scotland my beam was significantly brighter, possible due to the increased humidity.

Viewing the beam either looking down it away from the laser or down it towards the laser will make it appear brighter, with the latter being the brightest. Light scatters most in the direction of travel, second most in the opposite direction.
 

dden4012

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If your not up to putting parts together to build your own here is a reference for 638nm in single mode diode package.
PL-E Pro 635nm RED Laser
But honestly I think its way more host than that diode needs.
This is the diode
https://sites.google.com/site/dtrlpf/home/diodes/mitsubishi-635nm-110mw-single-mode-diodes
You may contact Podo and see if they use that diode in any of their handhelds since Sanwu scales their packages. You may get this in a guardian size host. And fyi Sanwu mentions single mode and multi mode but it is in the context of their driver setup not the diode.
 
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GSS

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Still though 300mw comes out to %38 as bright as 80mw of 532.
Like diachi said if I burn toast or smoke a cigg it makes a world of difference in seeing the beam. Its the one of the things keeping me from quiting:whistle:
 

diachi

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Still though 300mw comes out to %38 as bright as 80mw of 532.
Like diachi said if I burn toast or smoke a cigg it makes a world of difference in seeing the beam. Its the one of the things keeping me from quiting:whistle:

Yep, have a smoke (what you smoke is up to you!) or vape. Burning incense is another good option for increasing visibility. There's also cheap fog machines and fog in a can out there.

I'm quite lucky up here, we get ice fog in the colder winter months which is great for beams outside.
 

Crazlaser

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Anyway, I'll probably go for a Bitlaser 750mw or the Sanwu Guardian 638 next.
I like the idea of the Guardian being so compact and although I don't own it, I have the challenger 638 and I must say I am not really impressed with the beam. It's very pretty and visible in the sky but not even close to as bright as a 303 532 I have, even though it's 800mw. The reason I like the pocket series is just that; they fit in my pocket. In fact if I'm not carrying a 445 which I typically don't, I usually have my pocket 405 for my edc.
 
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I like the idea of the Guardian being so compact and although I don't own it, I have the challenger 638 and I must say I am not really impressed with the beam. It's very pretty and visible in the sky but not even close to as bright as a 303 532 I have, even though it's 800mw. The reason I like the pocket series is just that; they fit in my pocket. In fact if I'm not carrying a 445 which I typically don't, I usually have my pocket 405 for my edc.
Thanks! That's very helpful for me. That's very interesting that the 800mw beam isn't as bright as the 532 you have. I'd love to have a red that is apparent when you turn it on - just pops into your vision like a 532 does. Maybe I'm barking up the wrong tree. The relative brightness calculator says that 800mw of 638 should be 1.08x as bright as 80mw of 532. That's interesting that in practice it's not as bright for you. Gosh, I'm not sure what to do. I don't know if I feel confident enough to build a good laser, and I don't know if I want to drop $100 - $200 on a beam that won't be very exciting for me. I guess I'm chasing after something like that green or the 1W 445 I have, but maybe red isn't the way to go.

Maybe I should save up and get a 589 someday. But I don't want to wait that long I don't think :)

Thanks for that insight Crazlaser, that is definitely helpful.
 

Jhop

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You should consider getting a 445 1.5w or great from Sanwu, I have a 445 1.6w Spiker with g7, so more like 1.8w. But wow its beam is fantastic. very visible even with lights on, comparably I have a m140 build of a 445 I got from Pman. It is 1.2W(could be 1.6+ if I throw a g2 lens on it) and its beam is nowhere near as clear and bright as the Spiker. Granted its a lower power, but not by much. Nothing but great things to say about the Spiker though. Really a beautiful beam and host.
 

addebast

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The beam on my 1w 635 nm is about the same as my 90mw 520nm 303 in terms of visibility, altough with much poorer beamspecs.
 




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