Guide: A quick simple guide for Loupes purchase:
Plan for purchasing your loupes in adjance as some good manufacturer requires 4 to 6 weeks.
Make sure that the sales Rep is going to use your prescription if you have one. Going for magnification compensation instead of implementing the required lenses is not good for your eyes.
Make sure that the sales Rep is taking a picture of your face with the same frame that you chose. It is extremely rare to have both eyes on the same level and that will affect the clarity.
If you are not used to magnification, you can start with 2.5x or 3x. Your work mostly will be checked at 4x.
If you are purchasing light with the loupes, make sure that the light has 4 or more levels of intensity. Different projects requires different light intensity.
Make sure the light comes with the yellow filter.
Prismatic type of loupes is absolutely clearer than galilian type, prismatic usually starts with 3.5x.