I replied to the post above showing the view through the loupe as it shows the big problem with cheap loupes - spherical aberration. You can see that the center of the viewing area is very clear, but the outside edge is distorted. This will cause eye fatigue and headaches when using a loupe for a longer period of time. An aplanatic loupe will be as clear on the edges of the field as it is in the middle, and will greatly reduce eye strain and fatigue.
Cheers, Al
There seems to be some bias against stereo eye loupes here, which I don't think there's a good reason for. I understand that there's no question that pros are better than armatures, one eye or both. But there's no question that estimating depth with both eyes are better than just one eye, so if someone is good with one eye, then with both eye they wouldn't be worse off. Just like there are good one-eye loupes, there are also good stereo loupes, for example those used in medical surgery surely are. While not many watchmakers use the stereo kind, I don't think any surgeons use the one-eye loupe at all.
Also focal length and magnification power are directly related to each other, so it's mistaken to say one is more important than the other.
First for normal assembly work, I use a 4X loupe that is a flip down lens on my reading glasses. For most finer tasks, I use a 10X eye loupe on a wire that wraps around my head, and for very detailed work, I use this:
I replied to the post above showing the view through the loupe as it shows the big problem with cheap loupes - spherical aberration. You can see that the center of the viewing area is very clear, but the outside edge is distorted. This will cause eye fatigue and headaches when using a loupe for a longer period of time. An aplanatic loupe will be as clear on the edges of the field as it is in the middle, and will greatly reduce eye strain and fatigue.
Cheers, Al
Are you wanting to repair watches or examine them? Repair, you will need something like what George Clooney is wearing in my previous post. My idea of a triplet is this. Great for observing. Not good for repair. I have Bausch & Lomb and Asco. Both very nice. I also have some cheapies (sub $5 each) that work just fine. Not as clear but will work for hobby repairs. If you do it every day all day, you would want the best. Have you ever asked a hair stylist how much they paid for their scissors? Or a mechanic with his wrenches? A good place to go is casker.com or julesborel.com. You will get a good idea of average loupes. $15 to $50
NICE!!!! Here's my 1970's version. My best single purchase I have ever made. It matches all my groovy vintage watches well 😉. Maybe we should start a thread of "Show me your scopes"
Okay Aggie, here's mine.
I use a triplet for just looking at stuff, dual magnifier clip-on for general work, a springy loupe for close work and the scope for oiling etc.