can you guess? wrote: > Hallelujah! I don't know when this post actually appeared in the forum, but > it wasn't one I'd seen until right now. If it didn't just appear due to > whatever kind of fluke made the 'disappeared' post appear right now too, I > apologize for having missed it earlier. >
I'm contributing to the email list associated with the forum, so there are the uncertainties of timing of email delivery, plus whatever process at the forum end goes on when new email arrives, before it will appear in the forum. It could be kind of variable I guess. >> In a compressed raw file, it'll affect the rest of >> the file generally; >> so it essentially renders the whole thing useless, >> unless it happens to >> hit towards the end and you can crop around it. If >> it hits in metadata >> (statistically unlikely, the bulk of the file is >> image data) it's >> probably at worst annoying, but it *might* hit one of >> the bits software >> uses to recognize and validate the file, too. >> >> In an uncompressed raw file, if it hits in image data >> it'll affect >> probably 9 pixels; it's easily fixed. >> > > That's what I figured (and the above is the first time you've mentioned > *compressed* RAW files, so the obvious next observation is that if they > compress well - and if not, why bother compressing them? - then the amount of > room that they occupy is significantly smaller and the likelihood of getting > an error in one is similarly smaller). > The compression I see varies from something like 30% to 50%, very roughly (files reduced *by* 30%, not files reduced *to* 30%). This is with the Nikon D200, compressed NEF option. On some of the lower-level bodies, I believe the compression can't be turned off. Smaller files will of course get hit less often -- or it'll take longer to accumulate the terrabyte, is how I'd prefer to think of it. Damage that's fixable is still damage; I think of this in archivist mindset, with the disadvantage of not having an external budget to be my own archivist. > ... > > >>> Even assuming that you meant 'MB' rather than 'Mb' >>> >> above, that suggests that it would take you well over >> a decade to amass 1 TB of RAW data (assuming that, as >> you suggest both above and later, you didn't >> accumulate several hundred MB of pictures *every* day >> but just on those days when you were traveling, at a >> sporting event, etc.). >> >>> >>> >> I seem to come up with a DVD full every month or two >> these days, >> myself. I mean, it varies; there was this one >> weekend I filled 4 or >> some such; but it varies both ways, and that average >> isn't too far >> off. 25GB a year seems to take 40 years to reach >> 1TB. However, my >> rate has increased so dramatically in the last 7 >> years that I'm not at >> all sure what to expect; is it time for the curve to >> level off yet, for >> me? Who knows! >> > > Well, it still looks as if you're taking well over a decade to fill 1 TB at > present, as I estimated. > Yes, I'm agreeing with you there. >> Then again, I'm *also* working on scanning in the >> *last* 40 years worth >> of photos, and those tend to be bigger (scans are >> less good pixels so >> you need more of them), and *that* runs the numbers >> up, in chunks when I >> take time to do a big scanning batch. >> > > OK - that's another new input, though not yet a quantitative one. > I shot nearly as heavily back in the film era as I do now (within a factor of 2, let's say); but when scanning existing processed photos, I exercise some selection about which ones to scan, so the file count on disk isn't as large. (Much of my scanning was selective -- looking for photos for a class reunion, looking for photos of a dead friend; and the areas that have been more systematic were slides, which have been culled *twice* before scanning, and which were enough more expensive than B&W that I shot them more carefully. So I'm somewhat uncertain of the percentage I'd select in systematically going through the tri-x negatives). Very very roughly, I'm guessing I scan 1/4 of what I shot when I go through a roll systematically. And what I shot may have been as low as 1/2 as many as I'd shoot at the same events today. File sizes I choose for scanning 35mm range from 6MB to 150MB depending on film and purpose. So, very very roughly, an old scanned year might fill something like 1/4 * 1/2 * ( 30MB / 10MB) of the latest year (three eighths). There's so much windage on so many of those numbers that we're into WAG territory here. And other photographers will get very different numbers probably; they'll make different choices at various stages. > ... > > >>>> Even if you've got your original file archived, >>>> >> you >> >>>> still need >>>> your working copies available, and Adobe Photoshop >>>> can turn that >>>> RAW file into a PSD of nearly 60Mb in some cases. >>>> >>>> >>> If you really amass all your pictures this way >>> >> (rather than, e.g., use Photoshop on some of them and >> then save the result in a less verbose format), I'll >> suggest that this takes you well beyond the >> 'consumer' range of behavior. >> >>> >>> >> It's not snapshot usage, but it's common amateur >> usage. Amateurs tend >> to do lots of the same things professionals do (and >> sometimes better, >> though not usually). Hobbies are like that. >> >> The argument for the full Photoshop file is the >> concept of >> "nondestructive editing". I do retouching on new >> layers instead of >> erasing what I already have with the new stuff. I use >> adjustment layers >> with layer masks for curve adjustments. I can go >> back and improve the >> mask, or nudge the curves, without having to start >> over from scratch. >> It's a huge win. And it may be more valuable for >> amateurs, actually; >> professionals tend to have the experience to know >> their minds better and >> know when they have it right, so many of them may do >> less revisiting old >> stuff and improving it a bit. Also, when the job is >> done and sent to >> the client, they tend not to care about it any more. >> > > OK - but at a *maximum* of 60 MB per shot you're still talking about having > to manually massage at least 20,000 shots in Photoshop before the result > consumes 1 TB of space. That's a *lot* of manual labor: do you really > perform it on anything like that number of shots? > Photoshop files don't account for a significant amount of my total, no. As you suggest, I don't do that kind of full-blown workup on a very large percentage of the photos. I was getting off-track (for this discussion), wanting to explain why you might save the Photoshop files, rather than jumping ahead to agreeing that the space involved wasn't a big factor so it didn't matter much for this discussion. -- David Dyer-Bennet, [EMAIL PROTECTED]; http://dd-b.net/ Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/ Photos: http://dd-b.net/photography/gallery/ Dragaera: http://dragaera.info _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
