[X] My Assistant

[Guest_Zvezdichko_*]

I know it may be too early for such a thread, but an announcement has to be made.

The official website of the LROC camera is:

http://lroc.sese.asu.edu/

A brief description plus status is available here:

http://www.msss.com/lro/lroc/index.html

[djellison]

Is it just me, or - when loading the TIF's at full res, there appears to be some sort of interlacing (vertically). i.e. one column of pixels is bright, the next dark..bright, dark etc etc.

Attached zoom from http://wms.lroc.asu.edu/lroc_browse/view/nacl00000145

I guess some sort of adaptive amplification to create a pseudo enhanced dynamic range might be involved....or it might be a processing error, or it might be just something to do with the TIF's.

You can sort of back it out with some VERY rudimentary Photoshopping (doesn't quite get the shadows...someone cleverer than I could do it). I'd expect proper calibration (which is, after all, the point of these early images) would eliminate it. I found a different chunt and had a go at it

Attached thumbnail(s)

 

[Paul Fjeld]

Is it just me, or - when loading the TIF's at full res, there appears to be some sort of interlacing (vertically). i.e. one column of pixels is bright, the next dark..bright, dark etc etc.

I noticed that on a couple of the images but not all. More interesting is that the Zoomify image on the LROC website doesn't show that artifact.

[mcaplinger]

I noticed that on a couple of the images but not all.

You won't notice it on summed images because for those the even and odd pixels are averaged in the instrument. And as Doug says, you have to zoom all the way in to see it on a full-res image, and even then it's less noticeable on some images than others.

[Paul Fjeld]

I guess my point was that the LROC folks are doing a good job of modifying the raw data so that the striping effect is almost non-existent on the Zoomify images. I went and zoomed up to the pixel limit, grabbed the image and dug deeper. Yes, there is a hint of that striping in some of the image "blocks" but it looks more like a "jpeg-ing." They're very nice anyway!

[djellison]

so that the striping effect is almost non-existent on the Zoomify images.

Some images have it - some don't - as Mike explained. For those that have it - it IS in the Zoomify images, you just need to zoom in more than Zoomify can. There's no gradient between existing and non existing. It's one or the other.