I have just started to figure out the lighting issue. Unfortunately, you also need to be able to see what your are doing and that is a problem for me as I have a slight double image in both eyes that cannot be eliminated. It makes carving and engraving that much more of a challenge. It means more of the right kind of light and more magnification.
I think this happens to all of us as we age. I know that Wallace Gusler has been complaining for a couple of years that declines in his vision are causing him problems with his carving and engraving. He had mentioned stopping doing it, but I don't think that is an answer. I think we just need to work harder at working around these handicaps of aging.
One thing that I have just started to do with my engraving and will do with carving is to turn off the overhead fluorescent lights in the shop. I have a LOT of fluorescent light in the shop ( I am sure they can see my shop from space
) and I started to realize that I couldn't put enough direct light on the subject to overcome shadows that shouldn't be there or to create shadows that should be there. Turning off some or all of the ambient light helps you put the light you want where you need it. This is what you do with photography, but it came as something of a flash of insight to me as I struggled to overcome some long standing issues I had with engraving. Engraving and carving are very similar in many ways.
I even went as far as replacing lights on the bench I use for stocking, carving, and engraving. I replaced some square head swing arms lamps with halogen bulbs; with some regular round reflector swing arm lamps with standard Edison sockets. I installed 5000K LED bulbs of about 1600 lumen (roughly equivalent to a 100W tungsten bulb). These lights can get in closer to the work and also allow me to get closer to the work with more magnification ( I use prescription (much, much better than drug store ) reading glasses and Optivisor #4 lens).
The round reflector lets me get in a little closer and the LED is much cooler than the halogen; also allowing me to work with my head right up against the reflector. With the LED, the reflector stays cool. It doesn't hurt that my lamps (Electrix) have a reflector inside a reflector with an insulating air space between. Electrix lamps are all US made and are many orders of magnitude more expensive than the Chinese made lamps, but they are much better in terms of quality and function.
Both the halogen lamps I had and the new lamps have a 45" reach. This is much longer than anything else on the market. I have one on each end of a 6' bench which allows me to put light from two direction on most of my engraving and carving work. I bought my most recent lamps from MSC. Electrix will sell to you on their web site, but they charge $60 for shipping whereas MSC charged $10. Obviously, Electrix doesn't want to sell retail. I quickly got the message when I saw the shipping charge. MSC sells the lamps for MSRP so there is no difference in the actual price of the lamps, just the shipping charge.
I hope all this helps someone else.