Convert from Canon CR2 raw to PNG?

On 14 Aug 2006 03:36:42 -0700, wrote:

Hi all.
I’ve had a canon EOS350D for about a year now, and up until a month ago I always used high quality JPEGs for my images. I’ve recently gone the way of the raw file and will never look back.

I use photoshop CS2 to convert my images to JPEG – normally not even opening them into Photochop, just using the import plugin and saving to JPEG.

I have been investigating the use of PNG files and think that I should be using these instead of JPEGs to preserve detail in my photos. Unfortunately to convert an image to png in photoshop, I either have to export as a TIFF (45MB) and then batch convert to PNG or open into photoshop and then save as a PNG. Both ways lose the EXIF data and are slow (not to mention the TIFF way requires a temp folder of 5GB for the contents of a 1GB card full of raw files).

Is PNG the way I should be going or is there a better format I should use?

If PNG is the best way to go, is there some other way of converting from CR2 to PNG? Bear in mind for 99% of my photos, all I adjust is the exposure, brightness and white balance before I save them (and Gasp! Delete the CR2)

Seems pointless to me saving the raw photo then converting it to jpg. If you are going to do any editing on them you should keep them as 16bit .TIF files, then write them to cd. If you want to then make any changes you have the high quality ‘negative’ and you can then save them to whatever format if you need to compress them.

Regards

wrote:

Hi all.
I’ve had a canon EOS350D for about a year now, and up until a month ago I always used high quality JPEGs for my images. I’ve recently gone the way of the raw file and will never look back.

I use photoshop CS2 to convert my images to JPEG – normally not even opening them into Photochop, just using the import plugin and saving to JPEG.

I have been investigating the use of PNG files and think that I should be using these instead of JPEGs to preserve detail in my photos. Unfortunately to convert an image to png in photoshop, I either have to export as a TIFF (45MB) and then batch convert to PNG or open into photoshop and then save as a PNG. Both ways lose the EXIF data and are slow (not to mention the TIFF way requires a temp folder of 5GB for the contents of a 1GB card full of raw files).

Is PNG the way I should be going or is there a better format I should use?

If PNG is the best way to go, is there some other way of converting from CR2 to PNG? Bear in mind for 99% of my photos, all I adjust is the exposure, brightness and white balance before I save them (and Gasp! Delete the CR2)

Thanks

John

On Mon, 14 Aug 2006 04:52:25 -0700, GORIA22G wrote:

wrote:

Hi all.
I’ve had a canon EOS350D for about a year now, and up until a month ago I always used high quality JPEGs for my images. I’ve recently gone the way of the raw file and will never look back.

I use photoshop CS2 to convert my images to JPEG – normally not even opening them into Photochop, just using the import plugin and saving to JPEG.

I have been investigating the use of PNG files and think that I should be using these instead of JPEGs to preserve detail in my photos. Unfortunately to convert an image to png in photoshop, I either have to export as a TIFF (45MB) and then batch convert to PNG or open into photoshop and then save as a PNG. Both ways lose the EXIF data and are slow (not to mention the TIFF way requires a temp folder of 5GB for the contents of a 1GB card full of raw files).

I like png.

I use the Gimp and everything in my eos 350D is saved in raw then goes through Gimp and then saved in png format.

—
Neil
Delete l to reply

wrote:

Hi all.
I’ve had a canon EOS350D for about a year now, and up until a month ago I always used high quality JPEGs for my images. I’ve recently gone the way of the raw file and will never look back.

I use photoshop CS2 to convert my images to JPEG – normally not even opening them into Photochop, just using the import plugin and saving to JPEG.

I have been investigating the use of PNG files and think that I should be using these instead of JPEGs to preserve detail in my photos. Unfortunately to convert an image to png in photoshop, I either have to export as a TIFF (45MB) and then batch convert to PNG or open into photoshop and then save as a PNG. Both ways lose the EXIF data and are slow (not to mention the TIFF way requires a temp folder of 5GB for the contents of a 1GB card full of raw files).

Is PNG the way I should be going or is there a better format I should use?

If PNG is the best way to go, is there some other way of converting from CR2 to PNG? Bear in mind for 99% of my photos, all I adjust is the exposure, brightness and white balance before I save them (and Gasp! Delete the CR2)

Thanks

John

Sounds like you are creating 48bit color files (16 bits per color channel). 16bit files can only be saved in certain formats, interestingly one is PNG (there goes this theory). There is a drop down menu in the PS save dialog box to select your file types. If you are saving as a 24 bit files there are quite a few choices but PNG is there, much less in the 48 bit.
Do you throw out negatives too? I generally just keep the RAW files, unless I’m using the file for something else (printing, publication).

…

…

wrote:

I have been investigating the use of PNG files and think that I should be using these instead of JPEGs to preserve detail in my photos. Unfortunately to convert an image to png in photoshop, I either have to export as a TIFF (45MB) and then batch convert to PNG or open into photoshop and then save as a PNG. Both ways lose the EXIF data and are slow (not to mention the TIFF way requires a temp folder of 5GB for the contents of a 1GB card full of raw files).

Is PNG the way I should be going or is there a better format I should use?

Are you discarding the original RAW images ? If not, I can’t see why you’d want to save as PNG. There’s HARDLY (if any) any visual difference between a PNG image and a JPEG using low compression. (I can’t see any difference) This applies to viewing on the monitor or printing. All you’d be accomplishing is using more disk space.

(I know disk space is cheap, but I find the time involved in backing up and maintaining images can become a chore when the gigabyte count gets high enough)

If you’re keeping the original RAW image, then you have the ‘negative’ with all the information. If you have a real need for the highest quality possible, then you can always go back to the RAW ‘negative’.

If you aren’t keeping the original RAW file then you should be saving your images as 32 bit. Anything less and you are throwing away color detail. If I never kept my RAW files, I’d be using 32 bit TIFF rather than PNG. Of course I keep my RAW files so JPEG is just fine for archiving.

Of course you SHOULD be keeping the RAW files. They are the ‘negative’ and contain ALL the information your camera captured.

You really need to rethink the whole workflow issue.
Not to be disrespectful but you appear to need to spend more time reading about the basics of how to use Photoshop, or watching video tutorials, rather than posting to a newsgroup like this to find out the best solution for a problem that should not exist.
The benefits of 48bit color are debatable. Regardless, if you hold the idea of 48 bit color and jpeg in your head at the same time then you really are not understanding the relevant issues with regard to image quality. Storage is cheap so worrying about file size in terms of storage is like worrying about the cost of air in your tires when gas sells for $5 a gallon. File size is an issue not for storage but because Photoshop running on even the fastest CPU with gigabytes of RAM will eventually start choking on file sizes larger than 100mbs or after a session where many large files have been processed. If you do not print larger than 8.5 x 11 then most of the data in that immense file will be arbitrarily stripped out by the 8 bit printer driver, but that is another issue. Also another issue is that you cannot see 48 bits of color data and no display or printing process can reproduce 48 bit color, but I digress.
You should be thinking about lossless image processing and storage: layers and the PSD format. Label all your layers, save notes within the file, so when you reopen the image you will know what you have already done to it. Save your original raw image, as DNG if you like or whatever preserves the exif data (IMHO the least important image info) and save your processed image any way you like along with the PSD (this loses the "history" info but that will not matter if you have labelled layers).

…

wrote:

Hi all.
I’ve had a canon EOS350D for about a year now, and up until a month ago I always used high quality JPEGs for my images. I’ve recently gone the way of the raw file and will never look back.

I use photoshop CS2 to convert my images to JPEG – normally not even opening them into Photochop, just using the import plugin and saving to JPEG.

I have been investigating the use of PNG files and think that I should be using these instead of JPEGs to preserve detail in my photos. Unfortunately to convert an image to png in photoshop, I either have to export as a TIFF (45MB) and then batch convert to PNG or open into photoshop and then save as a PNG. Both ways lose the EXIF data and are slow (not to mention the TIFF way requires a temp folder of 5GB for the contents of a 1GB card full of raw files).

Is PNG the way I should be going or is there a better format I should use?

If PNG is the best way to go, is there some other way of converting from CR2 to PNG? Bear in mind for 99% of my photos, all I adjust is the exposure, brightness and white balance before I save them (and Gasp! Delete the CR2)

Thanks

John

You might like to try the DxO Optics program ( http://www.dxo.com ), which will convert to jpg, tiff, or dng, 8 or 16-bit, as you wish; as well it will correct exposure color from the exif data, and also correct for lens distortion and chromatic aberration specific to the lens used – again from exif – and does it all automatically. reads from one folder, puts the corrected images into any other folder of your choice.

Colin D.

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Posted via a free Usenet account from http://www.teranews.com

ColinD wrote:

wrote:

Hi all.
I’ve had a canon EOS350D for about a year now, and up until a month ago I always used high quality JPEGs for my images. I’ve recently gone the way of the raw file and will never look back.

I use photoshop CS2 to convert my images to JPEG – normally not even opening them into Photochop, just using the import plugin and saving to JPEG.

I have been investigating the use of PNG files and think that I should be using these instead of JPEGs to preserve detail in my photos. Unfortunately to convert an image to png in photoshop, I either have to export as a TIFF (45MB) and then batch convert to PNG or open into photoshop and then save as a PNG. Both ways lose the EXIF data and are slow (not to mention the TIFF way requires a temp folder of 5GB for the contents of a 1GB card full of raw files).

Is PNG the way I should be going or is there a better format I should use?

If PNG is the best way to go, is there some other way of converting from CR2 to PNG? Bear in mind for 99% of my photos, all I adjust is the exposure, brightness and white balance before I save them (and Gasp! Delete the CR2)

Thanks

John

You might like to try the DxO Optics program ( http://www.dxo.com ), which will convert to jpg, tiff, or dng, 8 or 16-bit, as you wish; as well it will correct exposure color from the exif data, and also correct for lens distortion and chromatic aberration specific to the lens used – again from exif – and does it all automatically. reads from one folder, puts the corrected images into any other folder of your choice.
Colin D.

Ooops! Mixup between png and dng. Still, dng might be worth looking at.

Colin D.

—
Posted via a free Usenet account from http://www.teranews.com

wrote in message

Hi all.
I’ve had a canon EOS350D for about a year now, and up until a month ago I always used high quality JPEGs for my images. I’ve recently gone the way of the raw file and will never look back.

I’d be interested in what went into this decision. Do you have a specific image that you believe does better starting from raw than high quality jpeg, or were you persuaded by someone’s discussion of the topic?

I use photoshop CS2 to convert my images to JPEG – normally not even opening them into Photochop, just using the import plugin and saving to JPEG.

It’s not clear that this is giving you an advantage over using jpeg from the start.

I have been investigating the use of PNG files and think that I should be using these instead of JPEGs to preserve detail in my photos.

Png is a lossless format, and there are situaitons – medical images for example – where this is crucial. With few exceptions high quality jpeg is adequate, though I would recommend against editing and resaving a chain of jpegs.

Unfortunately to convert an image to png in photoshop, I either have to export as a TIFF (45MB) and then batch convert to PNG or open into photoshop and then save as a PNG. Both ways lose the EXIF data and are slow (not to mention the TIFF way requires a temp folder of 5GB for the contents of a 1GB card full of raw files).

This should give you an indication of how many other people use this workflow: very few indeed.

Is PNG the way I should be going or is there a better format I should use?

Most people use PSD or TIFF files for lossless storage.

If PNG is the best way to go, is there some other way of converting from CR2 to PNG? Bear in mind for 99% of my photos, all I adjust is the exposure, brightness and white balance before I save them (and Gasp! Delete the CR2)

The CR2 is your digital negative, and I recommend that you keep it in preference even to your edited files. Raw files are smaller than the corresponding TIFF or PSD file, and since raw processing is an evolving art you may be able to get a better image from your files in the future.

That said, there is nothing wrong with using high quality jpeg as your main format. There is much more to getting good images than simply adjusting exposure and color temp. I would also recommend that you delve more deeply into editing your images with – what else – curves!
—
Mike Russell
www.curvemeister.com/forum/

wrote:

Thanks for all your recommendations.

The initial reason for my inquiry is because I currently have about 8000 photos on a telehoused server all availabl over the net as 120×120, 600×600 and full res images.

Set your Canon 350d to save the same picture in raw AND jpg. Save the raw file as your "negative", and use the jpg for low res. work.

AsleB, Oslo, Norway