On Thursday, March 24, 2016 at 10:51:18 PM UTC-4, wrote:
I need to purchase a magnifier so that I'll be able to do things like replace eproms and other small SMT's. I'm not looking to do LSI's with 150 pins Etc. Just mostly smaller stuff. For instance I currently have a board that needs an 8 pin Eprom replaced. I thought that I could do it with the magnifiers I have but the stuff is Just too small. I tried using a high res TV camera with a varifocal 3.5 to 8 mm lens but it doesn't make the image large enough. I was wondering what people are using to do this. Thanks, Lenny

I also have a headset magnifier with a pair of acrylic lenses. There is so much optical distortion through the plastic though that they're just about worthless.
I have a customer who does SMT repair work and I recently had him help me. I watched him replace an 8 pin SOT for me. He had a dual lens machine like something you might see on CSI.I don't know what the magnification was but when looking into this thing it appeared as though you were looking at an 8 inch by 8 inch field of view. It was really pretty impressive. The chip took up the entire field and the spaces between the legs were very well defined. With a small enough iron and a pick it was possible to first lift each lead one at a time, remove the chip with a slight twist and then tack the new one down. I was amazed at how easy it was with adequate magnification. I think the magnification was a lot more than 10X though. I also have a headset magnifier with glass lenses that I've used for years. It has about a six inch working distance and is just slightly better than reading glasses, but looking through this guy's machine was like seeing a whole new world. Lenny