An idea; Home made video microscope for SMT work.

[McPete]

Hi All,

Of late, I've found myself doing more and more work with SMT parts of smaller sizes, and some of the less friendly packages.

I had asked around some of the other electronics workshops on our campus, and two of them use these, while another uses a plain-old binocular microscope.

My trouble is that our department doesn't have the cool, free, $15 grand  or so to buy a Lynx, nor can I use a stereo microscope without going cross-eyed.

During my last, particularly arduous project, I kludged together a system using a small camera of a  name that has escaped me, and a tiny screen I salvaged from an autoclave that was being decommissioned. It was poor quality video, onto a small screen, but it got me there.

While my system worked, I can't help but wonder if some of you have a better solution? I'm presently toying with the idea of using a HD CCTV camera and a near-focus zoom lense, but I'm not as yet sure if that's possible.

When  I get back to the office, I'll throw up some pictures of my current arrangement.
Cheers,
P.

[IanB]

Surely such things are possible, but the two problems to overcome are depth of field (focus) and binocular vision. With a small enough camera (like the ones smartphones use) the depth of focus problem is perhaps solvable, but how easy is it to move and manipulate 3D objects with a 2D view? I've always found that peering through a magnifier with a single eye giving a flat field of view is OK for inspection, but it is not easy to work that way.

[TerminalJack505]

You can probably get a camera that will work with your existing microscopes.  Some scopes have a trinocular port which is specifically made for mounting a camera.  If your scopes don't have this then you may be able to connect a camera to one of the eyepieces.  You can then use a PC monitor or TV instead of using the eyepieces.

There are USB cameras that connect to a PC via USB and cameras that output the picture directly to a TV.

Here are some links to an Ebay seller...

USB PC cameras
Cameras with TV output

[free_electron]

usb camera's don't work well. there is too much time lag between what happens and screen refresh. it throws you off...

video will work.
Get a used Mantis on fleabay. i got mine for 150$ .. no need to spend 15K on  a lynx

[wkb]

Like this one:  https://www.eevblog.com/forum/projects-designs-and-technical-stuff/smd-assy-station/msg79393/#msg79393 ?

[bfritz]

I've never use the Lynx device, but it sounds great.

I've used stereo microscopes, and they are OK, but get tiring trying to hold your head in the right position... and the large stands, and inability to move them to the bench I am troubleshooting on is an additional problem.

I've tried using cameras, and the lack of 3D is a real problem.  I didn't find delay to be an issue, but the lack of depth of field, made it unworkable for me.

I've thought that Dental / Surgical Loupes should work well.  They are available at a lower cost, are only a couple ounces, and will move with you, so it doesn't matter which bench the microscope is at.

I would think about 3.5x would be a good magnification for SMT electronics soldering.  What do others think?

Has anyone ever tried Dental / Surgical Loupes?  Did you have a good or bad experience with them?

In case you aren't aware of what they look like, or cost, here are some available at a very good price:  http://www.medliteusa.com/?gclid=CJT6s_SXq68CFQrCtgodp3JlaA

[IanB]

I've thought about dental/surgical loupes, but I think they require you to get close to what you are looking at. The close proximity of your face to hot irons, solder splashes and flux fumes might not be a good combination?

[mikeselectricstuff]

I've used stereo microscopes, and they are OK, but get tiring trying to hold your head in the right position... and the large stands, and inability to move them to the bench I am troubleshooting on is an additional problem.

Vision Engineering's Mantis magnifiers avoid this problem and are totally awesome for electronics work, at a price.

[bfritz]

I've thought about dental/surgical loupes, but I think they require you to get close to what you are looking at. The close proximity of your face to hot irons, solder splashes and flux fumes might not be a good combination?

I think you are thinking of a jewelers loupe.  I have a 5x jewels loupe, with a focal length of 2".

Have you ever had the dentist or hygenist work on your teeth while wearing them?  They do not get inches away.

The link also supports this:  http://www.medliteusa.com/?gclid=CJT6s_SXq68CFQrCtgodp3JlaA

Note they offer working distances (distance from lens, to object) of 14" (35cm), 17" (45cm), and 21" (55cm).  That seems like enough distance for me.

Anyone ever use them for electronics work?

[JuKu]

-Mantis at $150? If you can, get one! I've spent a lot of time in front of one; highly recommended!
-Dental loupes might be good. After all, people who rely on good vision use those to earn living, and they are not limited by budget...

I now use a stereo microscope, so I don't have first hand (eye?) experience on loupes. But in general, microscope, loupe, or camera: You do want 3d. I guess that comment means that I think any camera solution is mediocre at best. Depth of vision is also important; you want a couple of inches at least, the more the better.

For magnification, the Mantis I used so much had 4x which was mostly ok. It had 8x option at a flick of a lever, and I did use that every now and then. We did have optics for 20x; to use that, you needed to unscrew one optical piece and replace it with another. The 20x was too much to work with: too narrow depth and too small work area. I used that very seldom and only for inspection. My current microscope is 5x. I do have 10x easily available, but I have used it only once in two years, and that was for inspection, not working. I think this is a long way to say that I find 5x to be optimal for SMD work. 3.5x is likely ok, even though it might be on the low side. It might be a good idea to use lower magnification on loupes than on static mounted microscopes.

You do want adequate work distance. As noted, it is not a good idea to put your nose too close to the fumes. Also, you do want the room to freely move your hands and tools under the whatever vision aid you have.

[daedalus]

if you stalk ebay then lynx come up quite regularly, got mine on there for around £500. Also worth searching "vision engineering" because some of their really old models come up for pocket change, and although a bit dated they still work fine. I stripped my mantis down and cleaned it myself as couldn't afford a service, and they are not too hard to renovate as long as the motor still runs. I tried loupes, magnified lights, and head mounted magnifiers, but they are all a real pain in the ass in comparison.

[EEVblog]

I would think about 3.5x would be a good magnification for SMT electronics soldering.  What do others think?

Not good enough IMO.
x4 bare minimum
x6 used to be my standard minimum on the Mantis, with x8 for finer stuff like 0402 or smaller.
The Mantis is an awesome tool if you afford it, or get used cheaply. If I could get one for $150, I'd buy 100 of them!
No way they go for that price here in Oz.
I've soldered under them all day (like 8 hours straight) without much strain at all.

Dave.

[mobbarley]

3 megapixel usb webcam and old canon telephoto lens. due to the tiny sensor size and very adjustable back focus I can achieve reasonable magnification from over a meter working distance (camera to be mounted on wall above desk).

[Spawn]

I got one of those TV loops for people with sight problems, it is a mono color version but I really like it since it is live video and there is no lag in the movement. Zooming works fine from 3x till almost 30x and it has focus on it.

I can’t take a picture of it right now since I got rid of the CRT monitor because I want a TFT monitor on it, I ordered a composite to VGA converter with more outputs so I can record things and use a TFT monitor.

Here two photos I took before, photo’s where taken for something else but I cut these out:


I will get a color version probably because I like to work with this system.

[codeboy2k]

I was thinking about this a few days ago, and pretty much came to the same conclusions in this thread.
Summary: 

• USB camera is too slow/lagging
• video camera is faster, but has no depth of field
• holding your head in an awkward position over a binocular microscope can be tiring.

So I thought, has anyone tried a binocular video camera ? using two video cameras and those video glasses, you could probably solder all day sitting up tall in your chair, without ever bending over, or straining your neck or back.

And you'll be the coolest looking guy (or girl) with a soldering iron !

[JuKu]

@codeboy2k: Interesting idea, and I see no reason why it shouldn't work if the cameras and glasses have good enough quality. If you mount the cameras wider than your eyes, the results with the enhanced depth perception should be very interesting.

See also http://xkcd.com/941/. 

[EEVblog]

I have a video uploading now.
A x10 objective Macro lens on my Canon HFG10 video camera mounted on an inverted tripod works very well.
Also, my old Sanyo HD-1010 with a x2 objective lens works a treat as well.

Dave.

[codeboy2k]

@codeboy2k: Interesting idea, and I see no reason why it shouldn't work if the cameras and glasses have good enough quality. If you mount the cameras wider than your eyes, the results with the enhanced depth perception should be very interesting.

See also http://xkcd.com/941/. 

ha! that xkcd comic gave me an idea to try to hack a proof-of-concept with my smartphone now