General approach to old photos

[tamhas]

I've been having an exchange with the editor of the newsletter for a small historical society. The society has quite a large collection of old photographs, very predominantly black and white, gathered from various sources and periodically someone comes up with a photo which they won't contribtute, but which can be scanned and published. However, as one might guess, a lot of these photos are in less than stunning condition and/or weren't great photographs to begin with. They are often very low contrast and not particularly sharp ... not exactly F/64 material, if you know what I mean. Sometimes they are damaged, but that seems the least of the issues.

What I am looking for is some guidelines of typical ways to proceed on enhancing these as well as is reasonable. Fortunately, final print size is typically no more than 5-6" on the long dimension. I am using Photoshop CS.

The editor has been scanning these at anything up to 2400 dpi, although the copies I have gotten are more typically a 150-300ppi and consequently I have resized them 2X-3X to get a few more pixels to fiddle with. Going forward I could expect to have higher resolutions.

The best general approach I have come up with so far, in part from some input on another forum, is to starting with the unsharp mask. I have tried two approaches. One is a 300-400% change on a radius of about 1.5 pixel with a threshold of 1 and the other is a two stage approach with an initial sharpening of about 50% on 5 pixel radius and then a 200% on 1 pixel, both threshold 1. This second technique has some advantages for smoothness, but depending on the print and the specific values can result in the graininess typical of multiply sharpened images.

Then I follow this with either auto contrast or equalization, most the former, but a couple seem to work better with the latter.

Then I will typically use levels to clip off a bit from each end, especially if there are any long tails, and giggle the center for the best effect.

Occasionally I will add in a little extra contrast or soften things with a little dust and scratches.

If there are areas needing burning, I will do that before the sharpening. Likewise any cropping of borders and such.

I will finish up with a bit of cloning to get rid of defects and artifacts.

Some sample before and after images can be seen at http://www.pbase.com/tamhas/tests

All suggestions welcome.

[mdavis]

I think it depends on what you are trying to show with the finished images. If the dust and scratches and blemishes are meant to be left as a "patina" of ageing, then they are fine images.

On the other hand, if you are trying to obtain a "new" look for the photos, each of them could take hours (days?) of hand work to re-create the image behind the flaws.

In general, two moderate applications of unsharp mask are better than one strong application. Each photo will react differently depending on its scanned resolution and on the original sharpness. But remember also that application of sharpening will also make flaws stand out like a sore thumb, so do you fix the flaws, or back off on the sharpening, or sharpen away?

[Leah]

I would be inclinded to fix the contrast first and then proceed to the sharpening. Also, particularly for shots of people, you might want to look into the "Smart Sharpening" technique described here -- it's likely to give you improved sharpness without the graininess.

[tamhas]

I don't see any virtue in the imperfections, but in the context I also don't feel a need to be complusive about getting rid of them either. E.g., the picture of the boy ... sure I could get rid of the mottled appearance of the sky, among other things, but it would take a lot of time and it is never going to be a great image. On the other hand, having the image have some snap off of the page so that people will actually look at it, rather than having it look like a gray blob, that is worth the work. If there are some dramatic flaws, those I will typically clone out since they are distracting.

[tamhas]

Originally Posted by Leah

I would be inclinded to fix the contrast first and then proceed to the sharpening. Also, particularly for shots of people, you might want to look into the "Smart Sharpening" technique described here -- it's likely to give you improved sharpness without the graininess.

I will definitively follow your link ... but my experience is that fixing the sharpening first produces a better result. E.g., the aerial photo in the link I posted just went nuts with autocontrast done at the start, but giving it some edges first produced a much more reasonable result. Admittedly, this was a particularly muddy photo, so it could work differently with a different starting point.

[Duv]

You both may be correct. I would suggest a "minor" sharpening to start followed by your contrast improvements and then sharpened again at the end.

Dave

[Flora]

Hi tamhas,

Welcome to RP!

In addition to the excellent tips you got already, I would advise to balance lights and shadows while working on the contrast, (to prevent too bright highlights and/or too dark shadows, loosing too many details ... particularly in people's faces)..... For the sharpening I usually do what Dave suggested "a "minor" sharpening to start ........ and then sharpened again at the end...."

I worked a bit on one of your pictures concentrating only on that, (hope you don't mind). I used luminosity and shadows masks 'playing' with the Layers' Blending, Curves and Levels.