I've researched this but only found simple tutorials about converting bitmaps like logos and geometrical patterns into vector art. What I have is a black-and-white facial portrait of a very good friend (passed on). I'd like a vector art version so I can enlarge without also uglifying. As I don't have any access to the unknown photographer's original image, I can't ask to have a higher-quality enlargement made from source. So, I'm wondering about taking what I do have--72 dpi 1024 x 700 pixel approx--and converting to vector. About 10 years ago I had a graphic design job and saw several eps images where the designers had carefully used gradients etc to simulate continuous tones in photographs. I'd like some direction to tutorials on how best to convert this photo to vector. I've experimented with Inkscape's "Trace Bitmap" but have a strong feeling that I'm reinventing the wheel. Is there someone out there who has already traveled the photo-to-vector path who might guide me to instructional material? Thank you.

Hi there.

Sorry to say but if you are not a skilled portrait artist, creating a vector image from a 1024/700 raster image
is reinventing the wheel either you trace automatically or manually.
A high resolution image or a series of higher resolution photographs for the details, you can use for manual tracing.
Without those, you would need to rely on anatomy knowledge and studies in portraits.

Another thing for the gradients: inkscape is now mostly capable to create such colour transitions by filtering, like blurring.
Which is raster based, thus would be problematic with high resolution printing.
Illustrator has gradient meshes that can mimmick photo-realism best, but still a higher resolution base image would be needed.

Can we have a look at the image?

Lazur URH thank you for detailed answers. I may have to save this for an advanced project some day.

I will ask the family about posting their loved one's picture. They're very protective.