David and others,
The best way to maintain the sharper than a needle point on your leads is to take a piece of fine grain sand paper and fold it into a pouch, tape the sides
so the graphite does not get all over. Put the lead into the pouch and kind of pump it up and down while rotating the holder . This thin point something like 1 1/2 to 2 inches long serves two purposes. One to reach into the finest detail to add density, the other to tell you when your applying too much pressure with the lead. The point breaks!
All retouching should be done on the base side. Some films have a "tooth" on the base side that readily accepts the lead. If there is no tooth on the base side you use a retouching varnish fluid made by Kodak to thinly cover the negative base. If you retouch with lead on the emulsion side, every stroke will show especially with condenser enlargers. By retouching on the base side you have the thickness of the base to aid in diffusing your pencil strokes. Crocein Scarlet and a drop of water can also be used add density to larger areas you must carefully mix the right strength, if you can see it on the neg as red, that is too much, should be a barely visable pink. Use the C.S. before
applying the retouching fluid. Can be washed off if necessary.
The adams is a handy tool, I usually use a tiny lite figure eight stroke and as someone else mentioned HB leads, I have practically every hardness/softness available but seldom use other than HB with my negs.
The Adams does not have the ability to make a good negative out of one that
has been made with poor technique. 90% of retouching can be eliminated
with prober attention to lighting and exposure.