Most of the views at Classic Stereoviews start as old stereo viewcards. If you have ever looked at them closely, you will have noticed that many are faded, have rips, corners missing, dust spots or blemishes of one sort or another. Many older views were poorly cropped, mismounted, and even had rotational error. The purpose of Classic Stereoviews is not to reproduce exact copies of old views, but to provide our customers with the best 3D experience of these views that we can provide.
When we choose an old card to offer our customers, we scan it at a high resolution and keep that original on file as a starting point. We do our production work on a copy.
The first step is to correct any rotational error. If a small rotation can be made to make the horizon truly horizontal or a building truly vertical, we do that. If the two views do not have the same rotational orientation, we make them match.
The second step involves getting the vertical orientation right. We line up the two views next to each other, pick a feature that is prominent in both the left and right view, then adjust one of the views up or down till it exactly lines up with the other view. We do this to an accuracy of one pixel. When the two views have perfectly aligned images (one is usually a little higher than the other) we trim the tops and bottoms of both views so the maximum amount of image that's common in both remains.
The third step is to roughly set the stereo window. This is where old views suffer the most. Just about all old views had too much unusable image on one side or another. This causes "window violations" which can make viewing uncomfortable. Similar to the second step, we line the images up, one above the other and crop off the areas that are not common to both views. When the two views are lined up side-by-side again, this makes for a more pleasing viewing experience.
The fourth step is to restore and retouch each view. We adjust the contrast and brightness, remove dust spots, stains, rips, and recreate the image in missing areas. In general, we make the view look as good as we possibly can.
Lastly, we bring the working views into our standard format, a 4x6 inch photo print. We fine tune the stereo window, add any copy and prepare a file to go to the photo processor. Each set is run individually when a customer orders it. This requires a day's processing time but eliminates the need to maintain a standing inventory. This means that we don't have to apply any warehousing cost to the prints.
When we get the views back from the processor we package them and send them off to the customer.