Saving very big TIFF files - !?

[Sfumato]

For some reasons (wide prints etc) I need very big TIFF files (size in pixels can be, say up to 18000x12000). As rather often a postwork should be done later it seems reasonable to save them with layers.
Sometimes my Photoshop CS2 refuses to save the files (LAB and RGB), but once I found a >5GB TIFF - !?
I tried saving with zipped layers, but despite the file size became larger (3,7 GB instead of 1,4 GB with single layer) I could not find layers when opened the saved file.
So the questions are:

1. Is there a way to save >4GB TIFF files?
2. Is there a way to retrieve layers from big TIFF files saved with compressed layers (ZIP) that do not seem to exist in saved variant (though the size make me suspect the layer info still exists)?

My hardware is 64-bit AMD with 4 GB RAM under Windows xp Pro (64-bit) if it matters.
Thank You in advance,
Sfumato.

[miress]

My god...5GB tiff???? I never seen that. It is poster around hockey arena??? Two kilometre long?

How resolution of pic have you?

[Sfumato]

Dear miress!
Speaking seriously 18000 pixels printed at 200 dpi make less than 8 feet long pictore. Is is very big? And 5GB TIFF file may run up to 5 GB even if it is not so big, say it may be 3x4 ft, but include 3 and more layers, masks that increase it's size significantly. Sometimes there's a need to save more than even 7 layers. The reason I need layered files - sometimes I need to change something in the picture. It is much easier when the layers are present. If I am wrong please do correct me - I will be grateful for Your constructive criticism and advice!

[miress]

ok, lets be serious...

your pics is really big....Did you tray save it as psd? But I think it will be bigger, but just try. Other question is, what how do you want to print it. Large sizes can print on 180 dpi, or more lower. 200 dpi is so enough. DPI is your way I think.

[bubbidge]

I have never heard of images being so big!

On a 2 metre x 2 metre print in the signage industry, the file size will be no bigger than 150MB. Its not photo quality obviously, but 4GB??? That doesnt sound right to me....

Hope you get it sorted anyway.

[Mike Bailey]

Photoshop layers are saved in photoshops PSD format, tiff, bitmap jpg, etc..... are single layer documents.

[miress]

Mistake Mike

Photoshop layers you can save as TIFF too. I know two formats to save layers: PSD and TIFF. New version of Photoshop offcourse.


Miress

[Mike Bailey]

New version of Photoshop offcourse.

I'm still on V6.

[Albacore]

Can I ask a question here? why such a high res for such a file size! 96 dpi would do for that size of format. However if you are secretly using google earth to take snap shots and are planing to bomb parts of the USA you may need that sort of res to look at the files so see where to go.

[Sfumato]

96 dpi makes 3,8 dots per mm! It means the dots are visible, so don't think it's suitable for hi-res photos.