Some Comments from Attendees

I heard the following statements about Image Restoration. Some of these were made by one person more or less in the words I put down here, and some were recurrent themes in the meeting. My commentary follows:

• It's often not necessary. (King)
  • This is true if one has a well-posed scientific question that can be posed directly to the data (i.e., to the aberrated image). If not, then one often has to look at an image for qualitative information (e.g., what does the object look like?)
• It's too mysterious. (King)
  • I sympathize with this view. Many forms of deconvolution algorithm are too mysterious. For example, just what does the Richardson-Lucy algorithm assume about the sky? More on this below.
• It's impossible. (Anon.)
  • What's impossible? Evidently, to find a solution to the convolution equation when the PSF is singular. Well, I think we all know that by now. The real point is what extra information do we need to get a unique solution, and what are the properties of that solution.
• It's too expensive. (many people)
  • Most processing described at this meeting can be done on a Sparc IPX. To run HST costs about 1 Sparc IPX per minute.
• It's too hard. (many people)
  • The technical obstacles are formidable: a spatially variant and poorly known PSF, strange noise, cosmic rays, undersampling, field rotation, etc. A better statement would be that it's very hard but not too hard.