Originally posted by jra
I guess you all can blame me for the image getting changed. I sent an email asking about why the image was retouched ...
I'm quite disappointed I didn't spot this thread before this, because as I was browsing over it, and saw the (newly edited) image in question, it
was pretty obvious to me that the image was covered in scratches, and that the (now quite subtle) cloning that was used was obviously in the scratched
areas - you can still clearly see the scratch remnants. But now I can only be wise after the event. dang.
These are, after all, film scans, and I know film scans VERY well. I've dealt with similar problems in many of my (terrestrial!) scans of 35mm and
medium format (same as Apollo Hasselblad) negatives and transparencies. I don't know how NASA did that initial (awful) scratch treatment, but I can
tell you that there are lots of ways to cover them - from careful use of the clone tool (very time-consuming, but can provide very convincing
results), to automated tools that intelligently (??grin) recognise scratches and dust and then apply a cloning, blurring or pixel duplication
The automated tools are notorious for leaving horrible duplicated areas and blurs - a wrong setting will create a nightmare. Manual cloning is
fraught with issues too, and if you do it at any less than full-resolution, or without being a master at it (modestly coughs..) then the traces are
blindingly obvious. And even a superb cloning job can generally be spotted by an expert. (Although I could easily better that new version by NASA...
But as always, the NASA originals are still there - why, you can even get access to the film itself, or the raw data streams, if you have a VERY good
reason. Needless to say they don't do the first very often - you can already see the scratch problem on that image...
It is also worth noting that AS SOON as you capture the image, you have altered it. In the case of Apollo filmscans, the choice of film determines
the colour gamut and response, the dynamic range, the graininess, etc. Then it gets scanned - a whole new set of parameters are applied to the image,
and a slight difference in settings, or even the age of the scanner can have dramatic effects.
Many Apollo images have been rescanned over the years as scanning technology has improved, so you may find several different resolutions, and you will
note subtle differences in colour and contrast. Later scans tend to show more scratches and dust, sadly - nature of the beast. None of the images
are TRUE colour, by the way - there is no such thing (happy to debate this, but it is getting a bit offtopic).
And then for digital imaging, the raw data response is determined by the type of sensor, the filters used.. So even though you can get at the raw
data (eg google 'FITS images') for most *digital* images made by NASA, it's still 'altered'...
Dranigus - I'm sorry, but anyone who thinks digital still cameras were used in the Apollo missions, really needs to do just a teeny bit more research
on the topic before offering technical comments...
Armap - your comment about manipulating a *negative* in the way you cloned out the spacecraft from that image, interests me -- what process are you