You will need a basic understanding of how to use Photoshop for this trick.
If the images aren't large enough click to enlarge. ;)
Layer duplicate or [ctrl + j] to create background layer duplicate.
Now add a layer mask. [Layer>Layer mask>Reveal all] to the new layer.
Make sure you select the upper layer instead of the mask and apply a Gaussian blur 4-7 pixels should do.
Your image should appear fuzzy like this.
Now click on the icon for the mask on the upper layer. Use a soft big brush and select black, paint over the areas of the image you would like to sharpen.
You will see your progress in the mask icon as you go.
To give more textural interest to your image go into brush library and try out the huge selection of faux & natural finish brushes to apply various shades of darker hues to create a really crusty tin type image like I did below. Create a new layer to apply your added special effects as you see in the finished portraits below.
the tiny arrow opens the brush library:
Completed black & white daguerreotype 'style' image
Or you could do a sepia tone version to really capture a moldering effect.
What is a daguerreotype and a tin type image
This is from memory.loc.gov
"The ProcessThe daguerreotype is a direct-positive process, creating a highly detailed image on a sheet of copper plated with a thin coat of silver without the use of a negative. The process required great care. The silver-plated copper plate had first to be cleaned and polished until the surface looked like a mirror. Next, the plate was sensitized in a closed box over iodine until it took on a yellow-rose appearance. The plate, held in a lightproof holder, was then transferred to the camera. After exposure to light, the plate was developed over hot mercury until an image appeared. To fix the image, the plate was immersed in a solution of sodium thiosulfate or salt and then toned with gold chloride.
Exposure times for the earliest daguerreotypes ranged from three to fifteen minutes, making the process nearly impractical for portraiture. Modifications to the sensitization process coupled with the improvement of photographic lenses soon reduced the exposure time to less than a minute.
Although daguerreotypes are unique images, they could be copied by redaguerreotyping the original. Copies were also produced by lithography or engraving. Portraits based upon daguerreotypes appeared in popular periodicals and in books."
and information about tintypes can be accessed here at www.rleggat.com