Thanks Ray, Very detailed information and I will use it.
I have found that both Photoshop Elements and Graphic converter will do batch conversions to .png. Graphic Converter seems to do it faster. Lloyd > > Lloyd, > > 1 jpg is a 'lossy' format, meaning that every time you save, or re- > save, a jpg file, the application doing the saving will throw away > some of the image information. If you save as a low-quality, or > small, jpg, then the saving application will throw away lots of > information each time it saves. This happens because, instead of > saving info about every pixel in the image, the program may save > something like "the next five pixels have roughly the same colour, so > use one saved colour for all five". png is not lossy, in that it > saves each pixel's colour information separately. This also explains > the sometimes very big difference in file size. > > 2 jpg does not allow you to save images that have layers or have bit > depths greater than 8-bit, png allows both. > > 3 png is public format designed to have a long life. It is unlikely > to soon be superseded by some different, 'improved' format, such as > often happens with formats created by the likes of Micro$oft and > Macromedia. > > 4 standard tiff is also a long-lasting and non-lossy format, so what > tips the balance in favour of png are factors like the fact that our > National Archives recommend use of png. I am sure that National > Archives did their homework before making that decision. > > Yes, you'll end up having to use a few more DVDs to store your > images, but you won't be losing image quality. Anyway, in five year's > time there will probably be an archival medium that will cheaply > store many DVD-worth of data. Also, when you convert all of your ,doc > files into rtf, you will end up with slightly smaller files, so that > may make you feel a bit better. > > Don't forget to also: > > 1 burn those crucial off-site copies of any archival data > > 2 burn optical media at the slowest recommended speed > > 3 always store optical media in the dark and in places that are as > cool as possible > > 4 create an intelligent indexing and labelling system for all of > your archived material so that you can quickly retrieve files when > you once again need them > > 5 in the case of archival Mac files, when you do the 5-yearly re- > save, add appropriate file extensions to those files that do not have > them. The current MacOS needs file extensions to automatically choose > the appropriate application with which to open the file. > > On 09/01/2010, at 2:51 PM, Lloyd White wrote: > >> I tried saving a photo from .JPG to .png using Graphic Converter, >> and the >> memory size more than doubled. For a large number of photos that >> would be a >> considerable increase in storage space. Is the quality so much >> better or is >> it only that it stores longer? >> >> Lloyd > > Regards, > > Ray Forma > 50 Harvest Road, North Fremantle WA 6159, Australia > Tel & Fax +61 (0)8 9335 6568 > Mob +61 (0) 428 596938 > > > > -- The WA Macintosh User Group Mailing List -- > Archives - <http://www.wamug.org.au/mailinglist/archives.shtml> > Guidelines - <http://www.wamug.org.au/mailinglist/guidelines.shtml> > Unsubscribe - <mailto:[email protected]> > -------- Lloyd White 22 Challenger Parade City Beach Western Australia 6015 Ph: and Fax: +61893858174 (08) 9385 8174 Skype: lloyd_white Email: [email protected] Write a Winning Job Application 4th Edition. http://lloydwhite.iinet.net.au/ Everyone seems normal until you get to know them. -- -- The WA Macintosh User Group Mailing List -- Archives - <http://www.wamug.org.au/mailinglist/archives.shtml> Guidelines - <http://www.wamug.org.au/mailinglist/guidelines.shtml> Unsubscribe - <mailto:[email protected]>
