Compression in tiff using photoshop

[Goku]

I am writing an action in photoshop to convert my jpeg images to tiff. When converting the image it tiff, should i choose an image compression such as LZW? Will I loose quality if I keep editing the image?

 

[Eric CAN]

Converting a JPG to RIFF won't bring the extra a TIFF has over a JPG. What have been lost is lost. As for saving TIFF, I never use compression. I use TIFF exlusively for post-processing to eventually save it in TIFF for the prints. After this, I'll save in JPG and resize it for the web.

Hope this helps a little

--
Eric Cote

Galleries :

http://gallery.bytephoto.com/DRHangar

Birds : http://gallery.bytephoto.com/showgallery.php?cat=3149&ppuser=87&password=&page=1

Macros : http://gallery.bytephoto.com/showgallery.php?cat=3154&ppuser=87

Equipment list in profile

 

[DannyV]

Yes it is OK to choose compression with tiffs. LZW and Zip are both lossless formats. However using jpeg compression with a tiff would probably result in the same degradation from repeated saving as would saving to jpeg.

Also note, there is very little advantage to compressing 16bit tiffs, in fact some of mine have actually "increased" in size when using compression. On 8bit tiffs, I usually see around 2-3mb of space savings.

I am writing an action in photoshop to convert my jpeg images to
tiff. When converting the image it tiff, should i choose an image
compression such as LZW? Will I loose quality if I keep editing the
image?

--
Daniel
http://www.pbase.com/dvogel11
300D tips http://www.bahneman.com/liem/photos/tricks/digital-rebel-tricks.html
300D FAQ at http://www.marius.org/fom-serve/cache/3.html

 

[Goku]

This was the answer I was looking for. I had read this elsewhere and I just wanted someone else to validate it for me. Thank you very much!

I am writing an action in photoshop to convert my jpeg images to
tiff. When converting the image it tiff, should i choose an image
compression such as LZW? Will I loose quality if I keep editing the
image?

--
Daniel
http://www.pbase.com/dvogel11
300D tips
http://www.bahneman.com/liem/photos/tricks/digital-rebel-tricks.html
300D FAQ at http://www.marius.org/fom-serve/cache/3.html

 

[bds231]

As Eric started to say, merely re-saving JPEGs as TIFs won't get you anything. Once JPEG compression introduces artifiacts into the image, they're there to stay no matter what format you use.

Where TIF can help is if you're editing your images anyway. Everytime you save in JPEG, quality degrades a little bit more (even if you just open the file and resave at highest quality). This is not true in TIF -- saving it will not decrease the quality -- and that's the reason to use it.

Re. TIF compression: the only reason not to use it is if you're concerned about compatibility with old (that is, very old, eg. older than, say 10 years) programs. LZW and ZIP compression will not, by definition, affect the image itself in any way.

Ben

Converting a JPG to RIFF won't bring the extra a TIFF has over a
JPG. What have been lost is lost. As for saving TIFF, I never use
compression. I use TIFF exlusively for post-processing to
eventually save it in TIFF for the prints. After this, I'll save in
JPG and resize it for the web.

Hope this helps a little

--
Eric Cote

Galleries :

http://gallery.bytephoto.com/DRHangar

Birds :
http://gallery.bytephoto.com/showgallery.php?cat=3149&ppuser=87&password=&page=1

Macros :
http://gallery.bytephoto.com/showgallery.php?cat=3154&ppuser=87

Equipment list in profile

 

[Goku]

Thank you for your explanation. The reason why I was converting JPEGs to TIFFs was because I was converting the files that were saved by my drebel. So nothing is really lost at that point. Then the next logical step would be to convert it to TIFF. And your explanation has helped me to decide which tiff compression to use. Thanks!

Where TIF can help is if you're editing your images anyway.
Everytime you save in JPEG, quality degrades a little bit more
(even if you just open the file and resave at highest quality).
This is not true in TIF -- saving it will not decrease the quality
-- and that's the reason to use it.

Re. TIF compression: the only reason not to use it is if you're
concerned about compatibility with old (that is, very old, eg.
older than, say 10 years) programs. LZW and ZIP compression will
not, by definition, affect the image itself in any way.

Ben

Converting a JPG to RIFF won't bring the extra a TIFF has over a
JPG. What have been lost is lost. As for saving TIFF, I never use
compression. I use TIFF exlusively for post-processing to
eventually save it in TIFF for the prints. After this, I'll save in
JPG and resize it for the web.

Hope this helps a little

--
Eric Cote

Galleries :

http://gallery.bytephoto.com/DRHangar

Birds :
http://gallery.bytephoto.com/showgallery.php?cat=3149&ppuser=87&password=&page=1

Macros :
http://gallery.bytephoto.com/showgallery.php?cat=3154&ppuser=87

Equipment list in profile