Without damaging the photo, I mean.
I have an old portrait photo (b&w) of my aunt from the 40s. Her sister took it upon herself to “augment” my aunt’s hair with some drawn-in curls.
Digital retouching will be difficult, though I will try it.
But is there any technique for removing pencil marks from the original photo without ruining the photo in the process?
It may be a glossy print. An artists soap eraser might lift the graphite pencil marks if done carefully.
A professional would leave the original untouched, make a photographic copy and retouch the copy to restore its initial 1940 appearance.
Copy and save the original “as is,” tinker to your heart’s content with copies. 
Things that used to be used for cleaning film (negatives) in the past were 1-1-1 Trichloroethane and “Perc” (dry-cleaning solvent) but either will be nearly impossible for a consumer to find.
Rubbing (isopropyl) alcohol might do the trick. You can get this at the drugstore. Work as dry as possible with it - ie: don’t soak the print with it, and use just enough to barely dampen a q-tip. Test on an edge of the print first to see that it doesn’t damage the print.
Another possibility is really not for the faint of heart, but a scalpel or x-acto knife can be used to scrape the pencil off the emulsion.
Given the pretty decent chances that any cleaning attempts will damage the print (especially with the assumption that this is your first attempt at restoring a photo) it may be best to scan it and repair it digitally.
You’re more than welcome to email the scanned photo to me; I have some excellent retouching tools and a fair bit of practice using them. I suggest a format that uses little or no compression–this will result in a large file, but will maintain the image integrity as much as possible.
Thanks, Q.E.D. That’s very kind of you (and very helpful, since I have only rudimentary skills). I will send the file along. Please let me know what you think. Please don’t put yourself out, though, if it would be a time-consuming chore.
Another reason not to tamper with the original: there are probably indentations caused by pressure on the pencil, making removal even more difficult, since the marks are below the surface. Plus, even if you can remove the graphite, the indentations will remain.
Definitely do it digitally and keep the original. Plus, you’ll be able to enhance the contrast, sharpening, etc. But if your skills aren’t up to it, take it to a professional.
If you open a free Yahoo! email account you can send as large a file as you want without having the email be large.
What they do is put a high-resolution file in Yahoo! photos and a thumbnail in the email. When you click on the thumbnail it links you to the photos version.
And you can also send a copy to me and I’ll also take the pencil mark out. My email is in my profile.
Please check your inbox Q.E.D.
(Is 600 dpi OK, or is higher resolution needed?)
David Simmons, I have sent the file to you too, if you’d like to take a crack at it. Thanks for the offer!
Check your email.
Thanks for taking a look David Simmons. Not to look a gift horse in the mouth you understand (because I do appreciate the help), but the photo you emailed still seems to have the pencil marks. (?) Or am I missing something?
Got it. Doesn’t look like it’ll be too bad
Ok, check your email, spoke-. It still needs polishing up, but I wanted to make sure you’re happy with what I have so far.
Thanks, Q.E.D. Looks great. Very kind of you.
Not to worry. the object is that your are satisfied.
I am puzzled though. I see a mark on the left forehead that I missed. Other than that I don’t really see any obvious pencil marks. In the hair at various positions around the edges there are what could be artistic retouching. Is that what you are talking about? I don’t see any disfiguring pencil marks. I can remove the retouch, if that’s what it is, or make it look like the rest of the hair.
Did you send back the right version of the photo?
Thanks David Simmons.
Q.E.D. did a nice retouch for me, so problem solved.
I really appreciate y’all devoting time to this.
I was slipshod in reading your email and missed about the penciled in curls completely. I emailed Mod 1 just now.