I know about the PNG thread, but we should really be looking into setting a standard for the Wiki. Do we see this as an extension of what the museum would be? Typically you would be looking at a .TIFF format. This site has a good starting point for resolution and DPI. http://www.archives.gov/records-mgmt/initiatives/digital-photo-records.html Just something to think about as it is something Ive worked on during my Master's program.
Like I said, it depends on what the Wiki is. If it is an extension of the museum, it needs to be museum quality, following archival standards.
I'm guessing since that thread about PNGs is gone now, it would be acceptable to use those? My video camera takes JPEG photos but they seem high quality since it's a 1080p camcorder. EDIT: For text documents, I assume PDF is the go?
JPEG isn't high quality, at all. It's a user format, which obviously has a purpose but it isn't an archival format. Even for text, there are standards that should be followed. I'm just trying to figure out if this is an extension of the museum, in which case we should be pushing for high quality, archival formats, or if it is "just" a wiki in which case we would eventually have to do everything again.
I know JPEG isn't ideal. I'll have to see if there is a way to change that on my camcorder. I would suggest raw, but I think there would be issues since every camera encodes differently.
Tiff when possible with original content. If the only image available is the original lossy format, it should probably be posted as-is or converted if possible without image degradation.
Which is why TIFF is the standard. Edit to assembler: I agree. Obviously I would never say no to content that doesn't exist in another form, but you would hope that original research would be done in many cases hah.
I'll soon have some free time and maybe start checking some 80's and 90's game magazines. I might do some scans for the museum (if i find something interesting / anything you are looking for) but my Canon MP230 can do a maximum resolution scan of 600 x 1200dpi. Would that be enough?
The document you linked before has been superceded several times. The current standards are at: http://www.archives.gov/records-mgmt/policy/transfer-guidance-tables.html To be honest, tiff is probably only the prefered archival format now because it has been the prefered format for so long. Changing archival types defeats the purpose. Ironically tiff containers can be used to support image variants that defy the very rules set forth as the standard. For instance, no point prefering them over jpegs if they actually contain a jpeg, and they can wrap vector drawings as well. It is near-native format for scanners though, which simplifies things.
Surely it's just a website? Websites require pictures for viewing, preferably of a resolution that's nice but not so huge that it's going to cause high bandwidth use. That's why web images are usually 72dpi. If you're really going to be fussy and say it has to be a TIFF image at 300dpi, then you should be picky about equipment. How many people have an infinity curve, studio lighting and a professional digital SLR camera with professional lenses? Or a professional-grade scanner? Because, if not, what's the point? Most cameras take pictures in JPEG so it's already in a lossy format, and several compact cameras don't even use 300dpi. Is the wiki actually going to host scans? There's a whole legality issue that arises, in that case. Taking a photo of a dev system is one thing, scanning in confidential manuals, even if it's a "dead" system, is copyright infringement. Yes, in practice it's often overlooked, but they're still copyrighted, regardless. And on that note, people do tend to scan at excessively high resolutions for a text manual. TIFF files aren't necessarily lossless, by the way. They can be lossless, but they can also be lossy. Yes, you'd be pretty stupid to save them in a lossy compression, granted!
Maybe a suggestion: PNG/JPG (compressed) for most page loading and display, but a link to TIFF/lossless for archival images if the TIFF is available? This would allow for both, but would keep pages fast and bandwidth low. It could be both a wiki and a museum. Also, an option could be that when a TIFF is uploaded, a lossy PNG/JPG is created for main display automatically, thus reducing a need for a second upload. Just sayin'.
The DPI property of an image is irrelevant for displaying it on your screen. It's a myth born out of early use of Macs for desktop publishing. The DPI property only relates to printing and desktop publishing. E.g. an image flagged as 400dpi that's 800px across should print out 2 inches wide on paper. The advantage of TIFF isn't that it's lossless (which you've correctly identified as not necessarily true), the advantage is that TIFF files can have arbitrary bitdepths. PNG and JPEG are limited to 24bit RGB or 32bit RGBA. For instance, even entry-level dSLR cameras can capture 12 bits per channel (36bpp RGB) in their RAW files. You'd lose that in converting to PNG or JPEG.
^^ tiff or tga? always saving scans as tga usually.. a bit expensive on the sizes, but it's good for certain documents, like vehicle repair manuals, aircraft diagrams and the like, has a near infinite level of detail, (larger quality/depth, larger filesize) and studio packages use them. (including CBM paint packages) bitmap has it's place too, but jpeg is the equivalent to mpeg as stated above! (lossy) not really encountered anywhere that uses tiff/tga (apart from the discussion here) but if tga could be integrated, it add another image support! after an upload, the UI can display it at a cost efficient level for the user, but when they download it from the correct link (not copying the UI frontend image supplied) they get it in the properly supplied format. (some cameras save as tga also) it relatively easy to convert from tiff to tga, vice-versa, just though i'd chip-in for convo sake! my bit, ignore! :cocksure: