Re: *ist D's relative file size capability
On 24 Sep 2004 at 14:33, Jack Davis wrote: I'm curious about all things photographic including digital. Since I own nine 35mm Pentax lenses, seems logical to check out the *ist D. While several have been playing with the phrase; *ist D..what a wonderful camera, I've also noted the many serious praises. Please help me understand what I read under the (more info) Specification tab on the BH site: 10D: Raw+Large=8.0MB Fine. 20D: Raw+jpeg(Large)=12.3MB. *ist D: Large(Raw)=10.5MB (Tiff)=18.1MB All note as excluding memory. The only one which seems to track with its sensor is the 10D. Trick wording? Meaningful? ...anyone? Hi Jack, These file sizes are not really meaningful, beyond an indication of how many shots you can expect to cram onto your chosen storage media. RAW files in their most basic form consist of a transcription of the RAW values corresponding to each pixel in the array, some of these are image forming and some are not. Secondly the bit depth of the ADC may be 12 bits but the RAW data may be padded (with zeros) to provide a 2 byte word or 16 bits per pixel, obviously these extra 4 bits per pixel are redundant but it still increases the RAW file size. On top of this some RAW file formats are stored uncompressed, some are compressed, most also contain EXIF information which can vary between camera models and also some (like the *ist D RAW files) can include an embedded JPG file. Most cameras offer similar capabilities WRT noise and exposure latitude and from my experience far more differences will be seen between the various post processing methods. Generally the in camera processing (TIFF JPEG) output really is little indication of the information that can be extracted from most camera RAW files in post processing. How does the *ist D's Dynamic Range compare? The capture latitude of the *ist D is very similar to most other cameras of the same age (better than most slide film but poorer than the most forgiving colour neg film) but you won't really get to see what it can do if you don't shoot RAW and use a good post processing tool like PS CS. The output differences between the Pentax Photolab program and PC CS RAW is startling, I didn't realize how bad the Pentax program was (and it was much better than the in camera generated files). Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
Re: *ist D's relative file size capability
Rob, Any chance you could post samples of similar images recorded initially as JPG and RAW? Or at least point to a URL? I have resisted buying PS CS (have Elements) so far, and want to try and evaluate how big the difference is, and whether, for my less critical eye, it is worth paying for CS. Thanks John On Sat, 25 Sep 2004 10:23:14 +1000, Rob Studdert [EMAIL PROTECTED] wrote: On 24 Sep 2004 at 14:33, Jack Davis wrote: I'm curious about all things photographic including digital. Since I own nine 35mm Pentax lenses, seems logical to check out the *ist D. While several have been playing with the phrase; *ist D..what a wonderful camera, I've also noted the many serious praises. Please help me understand what I read under the (more info) Specification tab on the BH site: 10D: Raw+Large=8.0MB Fine. 20D: Raw+jpeg(Large)=12.3MB. *ist D: Large(Raw)=10.5MB (Tiff)=18.1MB All note as excluding memory. The only one which seems to track with its sensor is the 10D. Trick wording? Meaningful? ...anyone? Hi Jack, These file sizes are not really meaningful, beyond an indication of how many shots you can expect to cram onto your chosen storage media. RAW files in their most basic form consist of a transcription of the RAW values corresponding to each pixel in the array, some of these are image forming and some are not. Secondly the bit depth of the ADC may be 12 bits but the RAW data may be padded (with zeros) to provide a 2 byte word or 16 bits per pixel, obviously these extra 4 bits per pixel are redundant but it still increases the RAW file size. On top of this some RAW file formats are stored uncompressed, some are compressed, most also contain EXIF information which can vary between camera models and also some (like the *ist D RAW files) can include an embedded JPG file. Most cameras offer similar capabilities WRT noise and exposure latitude and from my experience far more differences will be seen between the various post processing methods. Generally the in camera processing (TIFF JPEG) output really is little indication of the information that can be extracted from most camera RAW files in post processing. How does the *ist D's Dynamic Range compare? The capture latitude of the *ist D is very similar to most other cameras of the same age (better than most slide film but poorer than the most forgiving colour neg film) but you won't really get to see what it can do if you don't shoot RAW and use a good post processing tool like PS CS. The output differences between the Pentax Photolab program and PC CS RAW is startling, I didn't realize how bad the Pentax program was (and it was much better than the in camera generated files). Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998 -- Using M2, Opera's revolutionary e-mail client: http://www.opera.com/m2/
Re: *ist D's relative file size capability
On 25 Sep 2004 at 1:34, John Forbes wrote: Rob, Any chance you could post samples of similar images recorded initially as JPG and RAW? Or at least point to a URL? I have resisted buying PS CS (have Elements) so far, and want to try and evaluate how big the difference is, and whether, for my less critical eye, it is worth paying for CS. Hi John, No problems, I did the same experiment for some one else not long ago, I'm happy to share. Quick and dirty flash shot. PEF processed using PhotoLab, sRGB (embedded using PS) http://members.ozemail.com.au/~audiob/temp/_igp6865.jpg PEF processed using PS CS, sRGB http://members.ozemail.com.au/~audiob/temp/sRGB_IMGP6865.jpg PEF processed using PS CS, PhotoPro (should look pretty drab in a web browser) http://members.ozemail.com.au/~audiob/temp/PhotoPro_IMGP6865.jpg Photolab can only process files relative to AdobeRGB or sRGB colour spaces and it doesn't embed the colour space information so your apps have to be able to assign the CS on recognizing that there is no embedded colour space, this is a real PITA. Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
Re: *ist D's relative file size capability
Rob, Thanks! Very helpful. I'm assigning your response to a folder for future reference. Considerate of you to take the time. Jack --- Rob Studdert [EMAIL PROTECTED] wrote: On 24 Sep 2004 at 14:33, Jack Davis wrote: I'm curious about all things photographic including digital. Since I own nine 35mm Pentax lenses, seems logical to check out the *ist D. While several have been playing with the phrase; *ist D..what a wonderful camera, I've also noted the many serious praises. Please help me understand what I read under the (more info) Specification tab on the BH site: 10D: Raw+Large=8.0MB Fine. 20D: Raw+jpeg(Large)=12.3MB. *ist D: Large(Raw)=10.5MB (Tiff)=18.1MB All note as excluding memory. The only one which seems to track with its sensor is the 10D. Trick wording? Meaningful? ...anyone? Hi Jack, These file sizes are not really meaningful, beyond an indication of how many shots you can expect to cram onto your chosen storage media. RAW files in their most basic form consist of a transcription of the RAW values corresponding to each pixel in the array, some of these are image forming and some are not. Secondly the bit depth of the ADC may be 12 bits but the RAW data may be padded (with zeros) to provide a 2 byte word or 16 bits per pixel, obviously these extra 4 bits per pixel are redundant but it still increases the RAW file size. On top of this some RAW file formats are stored uncompressed, some are compressed, most also contain EXIF information which can vary between camera models and also some (like the *ist D RAW files) can include an embedded JPG file. Most cameras offer similar capabilities WRT noise and exposure latitude and from my experience far more differences will be seen between the various post processing methods. Generally the in camera processing (TIFF JPEG) output really is little indication of the information that can be extracted from most camera RAW files in post processing. How does the *ist D's Dynamic Range compare? The capture latitude of the *ist D is very similar to most other cameras of the same age (better than most slide film but poorer than the most forgiving colour neg film) but you won't really get to see what it can do if you don't shoot RAW and use a good post processing tool like PS CS. The output differences between the Pentax Photolab program and PC CS RAW is startling, I didn't realize how bad the Pentax program was (and it was much better than the in camera generated files). Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998 ___ Do you Yahoo!? Declare Yourself - Register online to vote today! http://vote.yahoo.com
