A few scanning tips

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Restoration of Genealogy Photos

Before    After

This is a 1917 photo, somewhat faded and damaged with a crease. It has been cut into an oval shape, and has the back of an old cardboard frame glued to it. The original is on the left, and the restored image is at the right.

The important tools are the histogram for restoring contrast, and the Clone Tool for repairing damage.   I scanned this at 600 dpi, not for detail, but for image size to aid working with the Clone Tool at enlarged size. The plan was to resample it smaller at completion (resampled to 25% size above). 300 dpi would really have been quite sufficient, and you can always work on the image when zoomed-in to 2X size (that's what I do to clean everyday scans of dust spots). I scanned it in color mode and converted to GrayScale and sharpened with the Unsharp Mask as the last two steps. If repairing stains and discoloration, it's often easier to work on it in color mode. This time, there was no good reason for color really, it was only because I wasn't sure yet if I wanted to leave it in color to show the original tone, or put it in grayscale.   Grayscale won. It does not change anything here, to work in color or B&W.

The scanning technique is NOT different from already discussed in the Simple Way to get better scans pages. There are four major peaks in this histogram data, and it seems reasonable that these would generally be associated with the tones in the dark dresses, the background, the lighter background, and the white dress.

Scanning this with the Black & White Points somewhat clipped restores the contrast. Clipping the histogram end points a bit more than this for more contrast is often better in many cases.

See the little tail of pixels at the black end?   It's almost always a good idea to clip these few pixels off (let them go to full black). Position the Black Point at the major base of the pixels, as shown here. Perhaps even inside of it to clip even more. Clipping tones at the Black&White Point ends can be dramatic, to increase contrast, and to restore faded or washed out color prints to the original colorful tones. Experiment!

In this case, the histogram is advising us that we should move the Black Point so that the gray tone of value 86 becomes black with a value of 0. Similarly, we positioned the White Point so that the gray tone of value 211 becomes white with a value of 255. Don't be concerned with those numeric values, we are judging this by the shape of this particular image's histogram data. We can see where the data starts and ends in this image. But this change increases the total range of the image tones from 211-86=125 to be instead 255-0=255, which is the full range of the image capability. Dramatically more contrast. Then we also lightened the image by raising the Mid-Point to 1.44 (done by sight for a pleasing result).

For example, compare the center girl's shoes in both larger images at the top of the page. We have black now. The same for the white dress, we have white now. This image has little detail in the white dress, but the original photo did not have it either, faded away perhaps. Clipping aggravates the loss of detail at the ends, and this is a major concern, so you always have to evaluate its effect.

Caution:   The histogram shows the data of the image. In this case, the image includes the cardboard frame too, which we intend to remove. It happens to be midrange tones in this case, but if that surrounding area was pretty much black or pretty much white, it would drastically affect the histogram data. We would be judging the image based on non-image components. So, the point is, having surrounding areas of black (thinking that we will crop it away later) can be detrimental to the histogram process. You will want to more carefully include only the actual desired area of the photograph. At least be aware of this problem.

Finishing with the Photoshop Auto Levels or PhotoDeluxe Instant Fix controls at completion is often good and dramatic. Those operations also adjust the Black & White Points with a little clipping, and the better job you do scanning, the less effect they have. When those operations essentially do nothing, then you've done a good job at the scanner. If they do a lot, you could have scanned it better. This job is better done in the scanner at time of the scan, when the original 30 bit data is still available.

Please excuse the harping, but experimentation is the key, to see all of the possibilities.

The best advice for hesitant beginners is WADE IN. You will have a very improved viewpoint after the first 5 minutes.


To restore damage, basically you have to repaint the bad spots. It's tedious, but not that difficult. Making the new work blend in well is much more important than exact artistic skill duplicating original detail. This is what the Clone Tool does, and most image programs have one. The magnitude of the work may look impossible at first sight, but it's really pretty easy, just keep at it. And remember, you can get away with a lot, it does not have to be nearly as perfect as you might think. You are working on a larger image that will be seen later smaller, and it will look better smaller than it does now.

Don't forget you have an EDIT - UNDO menu, you will use it a lot, there are lots of Oops waiting here. Programs with several levels of Undo are a real blessing. Some areas you may have to redo several times to get it right. You will quickly improve your skill with practice. Do save the file often so you can always get back to a good point if worse comes to worse, without having to go back to the beginning. You may want several versions of backup files, saving varying steps or stages of progress.

The Clone Tool takes care of photo crease and tear damage and the scattered spots, by copying similar color and detail from adjacent locations. You have options with the Clone Tool... several brush widths and varying feathered edges, and you will change back and forth often as you go. The Lasso Tool was used to remove the outer border outside the oval, and then the feathered Clone Tool was used around that oval edge to smooth it a bit.

PhotoDeluxe, Photoshop, PhotoImpact, and Paint Shop Pro have good Clone Tools, they all work about the same.

 

Here is a sample of the Clone Tool at work. The actual size of a ½ inch area of the original photo scanned at 600 dpi is a 300 pixel image. This is the Photoshop clone tool (called Rubber Stamp), but the Paint Shop Pro and PhotoImpact Clone Tools work the same and are as good. You can dab with the Clone Tool, or in some cases, you can drag it with the mouse, and it will reproduce a line from the adjacent area, shown here. The difference in these two images is due to one stroke of the Clone Tool. I dragged it from the upper right to the lower left, and it reproduced the hair color in the white creased area. You can see the start and end of the stroke by the circular shape of the Clone Tool Brush (a little larger than usual, set larger especially for this). The area "copied from" is immediately above the stroke, and adjacent to it, all the way along the stroke. This is one stroke, and it needs more clean up still, but you can see that the idea is that the Clone Tool will reproduce some similar detail in the damaged area. Notice the two highlights at the 1/3 and 2/3 stroke length are also reproduced. This reproduction of detail in the cloned area is the point.


Copyright © 1997-2010 by Wayne Fulton - All rights are reserved.


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