Tuesday, December 09, 2008

Photographing Oversized Pictures

Occasionally it is impossible or impractical to use your scanner on old photos and documents. A camera & tripod or copy stand is a good alternative.

These two websites may help:
How to build a (Cheap) copy stand.
http://www.coincommunity.com/forum/topic.asp?ARCHIVE=true&TOPIC_ID=19857

Getting Started: Copy Stand Shooting (uses a tripod & music stand and also teaches good technique)
http://www.videomaker.com/article/6807/

One problem when using a camera on old photos and documents is you can get a barrel effect & it is hard to get a perfect angle. In GIMP http://gimp.org/ (a free open source program) has a filter called “Lens Distortion” in Filters>Distortion where you can manually correct it (use the “Main” slider bar in the “Lens Distortion”). Then you can take care of any angle problems with the “Perceptive button” or Tools>Transform Tools>Perceptive. I just click & drag the ruler guides from the ruler across the 4 sides, then I use the “Perceptive Tool” to click & drag the corners of the frame or edges of the picture to the corners of the guide.

In Episode 038 of Meet The GIMP http://meetthegimp.org/episode-038-a-phython-in-a-barrel/ Rolf Steinort has written a plugin for GIMP that makes taking care of the Barrel Effect created by your camera easy. Some of my pictures it over corrected but it got me in the ballpark, others it did a wonderful job. I recommend watching his video & downloading the “Python source code” and adding it to your GIMP plugins. For Windows users unzip the file & paste the 3 files into “C drive>Documents and Settings>[[User name]]>.gimp-2.6>plug-ins” it will then appear as “Barrel distortion removal CA65” in “Filters>Distort”.

Rede made a video specifically dealing with the Barrel Effect & Perceptive Tool and how it applies with old photos & documents: http://blip.tv/file/1554370

2 comments:

meetthegimp said...

The script was finetuned for my camera. You have to change it for your values - the HowTo should be obvious from the video.

If there are any problems just drop a note in the comments for that episode.

Dennis said...

WOW that was a fast comment!!! Meet The GIMP http://meetthegimp.org/ is one of the best sites I know of if you want to learn GIMP & the forum is a great place to get questions answered.