Digital microscope for through hole & PCB flipping? - Page 1
Forum section: electronics / general

author: killingtime
author_rank: Regular Contributor
timestamp: August 22, 2021, 11:30:36 pm
content: Hi,I do a lot of through hole soldering and would like some soft of digital magnifier. Using head mounted magnifying glasses at the moment. 2.5xPCBs are mounted on a flip stand so I can rotate the board over after inserting the component, to solder it.I think stereo microscopes are out. I was almost set to buy one after hearing people rave about them, then I realised there's not enough distance from the lens to the PCB after getting the PCB holder underneath. So it's going to be a standalone camera, lens and monitor.All of the digital microscope reviews I've seen on YT have a very shallow depth of field (a few mm). This would mean me having to re-focus the camera each time the PCB is flipped - unless I get the PCB exactly level. That's going to get old very quickly. I suppose it depends on how narrow the DOF is.Is there a microscope that has 10-20x magnification and a large depth of field?Not sure what I should be searching for as none of the adverts I've seen mention DOF or working clearance, just magnification.Thanks.

author: Electro Fan
author_rank: Super Contributor
timestamp: August 23, 2021, 11:57:00 pm
content: This post is part of a thread that talks about some of the tradeoffs in digital cameras and optical microscopes. At the end of the post is a table that gives some measurements that might help you see some possible working clearances with an optical microscope. Somewhere earlier in the thread there is some discussion of the view from the digital camera used with the optical microscope.https://www.eevblog.com/forum/beginners/the-ergonomics-of-microscope-soldering-direct-optical-view-vs-cameramo-257888/msg3332530/#msg3332530

author: Ungolian
author_rank: Regular Contributor
timestamp: August 27, 2021, 08:00:45 am
content: I just went through the same thing. I bought a Hayear, and couldn't be more pleased. This one-https://www.amazon.com/gp/product/B0832LS8BK/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1Normally, the working distance is pitifully short. Since you are using a set of helping hands or something else that elevates the board, working distance is even more of an issue . If you have a small bench, that can be a problem too. Plus the field of view wasn't so great. I started looking for Barlow lenses and such, only to discover that the lens I had was too small for a Barlow. I think it is 28mm. Then I discovered that lifting the unit up would widen the field. I wound up mounting it about 30 inches above my bench, and solved 2 problems in the process. I don't need a Barlow now, and it's not taking up space on my bench. I can sit in my normal position too. You can see the lights and the bottom of the unit above my massive 27 inch monitor. You can't do that with a stereo microscope. I am somewhat limited by the size of the lens, as far as attachments go. I thought about a polarizing filter, but it really hasn't been necessary (the reflection off of the circuit board is from my camera flash, not the lights above). The field of view is about 3 1/2 inches wide, and 2 1/2 tall. You could increase that with a wider 35mm lens that will take a Barlow. But the visual working height of 2 1/2 inches would still be the same ( I stood the board up at a 45 degree angle to show that). Anything beyond that gets too blurry. This camera also has a nice zoom function, up to 5x. But at max, it's a little grainy because the lens is narrow and doesn't gather as much light. It's not really an issue for me, but had I known what I know now, I would have gotten a more standard 35 mm lens to increase the accessories I could use with it.

author: killingtime
author_rank: Regular Contributor
timestamp: August 28, 2021, 10:45:57 am
content: That looks like a good set up. Camera isn't in the way and gives enough magnification to get the job done. You're not bent over a microscope for hours on end either.I've got a 48MP camera on order.Thanks.

author: Ungolian
author_rank: Regular Contributor
timestamp: August 28, 2021, 11:17:32 am
content: You're welcome. Depending on the light source you are using, you may need a polarizing filter. The ring lights that mount directly on the lens point straight down, and can cause unwanted reflections. The flex lights I have are great in that I can position them off axis to avoid that. Enjoy!Almost forgot, you're going to have to rotate the mounting shaft 180 degrees. It's not a big deal, the shaft attaches to the base with ring nuts. You'll see what I mean.