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05/03/2006 02:54:16 PM · #1 |
| According to the newsletter they've now started accepting .JPG(12) which should save us all a bit of work and more importantly put many more images on a single disk! Sweeet... |
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05/03/2006 08:52:31 PM · #2 |
I don't get it. Here's what Alamy says are the guidelines:
"Images must be saved at Jpeg level 12 - the highest quality setting.
Images saved as Jpegs must be at least 48mb in size when uncompressed."
They go on to say that this will save disk space and speed up CD/DVD burning.
Questions. How can you tell how big a Jpeg is uncompressed? Aren't all Jpegs compressed? How do you "uncompress" a Jpeg?
When I save an image in PSP X I have the option to select the compression setting. The highest (best quality) is 1. As I move the number up it lowers the file size (example, DPChallenge Challenge Entry can be anywhere from 6 to 12 to get to 150k limit at 640px).
Think I'll stick to TIFF files. ;^) |
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05/03/2006 09:36:24 PM · #3 |
| JPG(12) is lossless compression. Basically what they're saying is prepare your image as usual then save it as JPG(12) instead of TIFF. File sizes will be much much smaller. |
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05/03/2006 09:48:52 PM · #4 |
Originally posted by Count:
JPG(12) is lossless compression. Basically what they're saying is prepare your image as usual then save it as JPG(12) instead of TIFF. File sizes will be much much smaller. |
Not even a 1ds mark II at 17 megapixels could make an uncompressed 48 megabyte file. The only cameras that could make this are medium formats with Phase1 backs I think.
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05/03/2006 09:51:22 PM · #5 |
| If you open the jpg image in photoshop the image status bar will tell you the uncompressed file size. |
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05/03/2006 10:01:55 PM · #6 |
Ok. I see something similar in PSP X. I don't have JPG(12), but I do have an encoding option (never paid attention to since I use standard for JPG's). One of the encoding options is 'Lossless encoding' type.
Always learning something new at this place! ;^)
Wait...if I chose the 'Lossless encoding' then I'm still working with a large file size - yes/no? Back to the same burn time, # of images per disk, etc...hmmm.
Thanks for the feedback. I'll have to play with it for a bit to see if this Alamy option is viable for me. |
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05/08/2006 06:31:52 PM · #7 |
Originally posted by wavelength:
Not even a 1ds mark II at 17 megapixels could make an uncompressed 48 megabyte file. The only cameras that could make this are medium formats with Phase1 backs I think. |
Sorry, but not true. They fully expect us to upsize our images until they reach 48mb. They happily accept images made with normal dSLR camera.
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05/08/2006 06:51:48 PM · #8 |
Originally posted by idnic:
Originally posted by wavelength:
Not even a 1ds mark II at 17 megapixels could make an uncompressed 48 megabyte file. The only cameras that could make this are medium formats with Phase1 backs I think. |
Sorry, but not true. They fully expect us to upsize our images until they reach 48mb. They happily accept images made with normal dSLR camera. |
More than that, a 17 megapixel camera produces 48 meg TIFFs without requiring any upsizing. A 48 meg (8-bit) TIFF requires 16 megapixels, at 3 bytes per pixel (1 per channel).
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05/08/2006 07:17:43 PM · #9 |
| 6.3 megapixel 10D creates a ~36 MB tiff without resizing. When your open your raw image in ACR simply setting the size to the next level up (11.2 MP) will result in a ~64 MB tiff. |
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