convert psd to jpg?

louise wrote:

Photoshop 7, Win XP
…
The original psd was 18,000 kb and the saved as copy jpg (with jpg options at their highest), is only a little over 2,000 kb.
How did 18,000 kb (because of Photoshop adjustments), turn (back?) into 2,000 kb?

PSDs are losslessly compressed, JPEG achieves much better compression at a cost of quality. The difference in size would be expected.

Thanks.

Louise

"louise" wrote in message

told me that because of the layers, it could be saved as a copy (yellow triangle warning at the layers checkbox).

If you save a layered PSD file as a jpg, any layers are flattened, with the corresponding loss of file size that each layer consumes, in addition the jpg compression will significantly reduce file size.

In article <434958e9$0$73595$>,
"Harry Limey" <harrylimey(at)Lycos.co.uk> says…

"louise" wrote in message

told me that because of the layers, it could be saved as a copy (yellow triangle warning at the layers checkbox).

If you save a layered PSD file as a jpg, any layers are flattened, with the corresponding loss of file size that each layer consumes, in addition the jpg compression will significantly reduce file size.

Thanks – that explains it. But leads to one more question:

How much is picture quality affected by the flattening of each of these layers? In other words, I guess I’m asking what actually happens to the quality of a flattened layer.

Louise

In article , Louise
wrote:

How did 18,000 kb (because of Photoshop adjustments), turn (back?) into 2,000 kb?

Echoing what others have said, this is normal. I’ve just been editing some scans from prints and then converting them to jpegs. A typical psd size (converted from tiff) is 30-50 Mbytes; the jpegs are 3-5 Mbytes.

—

Roger

louise wrote:

How much is picture quality affected by the flattening of each of these layers? In other words, I guess I’m asking what actually happens to the quality of a flattened layer.

Quality isn’t affected by flattening, you are simply squashing the layers together and losing the ability to edit them individually.

Cheers,
Nicholas Sherlock

Nicholas Sherlock wrote:

louise wrote:

How much is picture quality affected by the flattening of each of these layers? In other words, I guess I’m asking what actually happens to the quality of a flattened layer.

Quality isn’t affected by flattening, you are simply squashing the layers together and losing the ability to edit them individually.

Except for text layers and vector layers. When those layers are flattened, they are rendered and thus they lose quality (because a vector can print at the highest printer resolution, while a rendered layer will print at the resolution of the rendered immage).

—
Johan W. Elzenga johan<<at>>johanfoto.nl Editor / Photographer http://www.johanfoto.nl/

In article ,
louise wrote:

The original psd was 18,000 kb and the saved as copy jpg (with jpg options at their highest), is only a little over 2,000 kb.
How did 18,000 kb (because of Photoshop adjustments), turn (back?) into 2,000 kb?

That’s what JPEG does.

JPEG is a compressed format. A JPEG file will always be smaller than the original image because of this compression.

JPEG is "lossy" compression. That means in order to make the file smaller on disk, image information is discarded and the image is deliberately degraded in quality.

Why did you save as a JPEG? Is there some specific reason you had to use JPEG, instead of PSD or some other format? JPEG degrades quality; the JPEG format was invented for situations where file size is critical and image quality is not important. If you do not have a specific and good reason that you have to use JPEG and can’t use some other format, you should not save your images in JPEG.

—
Art, photography, shareware, polyamory, literature, kink: all at http://www.xeromag.com/franklin.html

In article ,
louise wrote:

How much is picture quality affected by the flattening of each of these layers? In other words, I guess I’m asking what actually happens to the quality of a flattened layer.

Flattening a layer does not change quality. However, saving as a JPEG does decrease quality–that’s what JPEG is intended to do.

—
Art, photography, shareware, polyamory, literature, kink: all at http://www.xeromag.com/franklin.html

In article ,
says…

In article , Louise
wrote:

How did 18,000 kb (because of Photoshop adjustments), turn (back?) into 2,000 kb?

Echoing what others have said, this is normal. I’ve just been editing some scans from prints and then converting them to jpegs. A typical psd size (converted from tiff) is 30-50 Mbytes; the jpegs are 3-5 Mbytes.

Thanks everybody – I understand.

Louise

In article <
server2.tampabay.rr.com>, says…

In article ,
louise wrote:

The original psd was 18,000 kb and the saved as copy jpg (with jpg options at their highest), is only a little over 2,000 kb.
How did 18,000 kb (because of Photoshop adjustments), turn (back?) into 2,000 kb?

That’s what JPEG does.

JPEG is a compressed format. A JPEG file will always be smaller than the original image because of this compression.

JPEG is "lossy" compression. That means in order to make the file smaller on disk, image information is discarded and the image is deliberately degraded in quality.

Why did you save as a JPEG? Is there some specific reason you had to use JPEG, instead of PSD or some other format? JPEG degrades quality; the JPEG format was invented for situations where file size is critical and image quality is not important. If you do not have a specific and good reason that you have to use JPEG and can’t use some other format, you should not save your images in JPEG.

It is my impression that not everyone can open a psd file. Is that true?

So, I used the best level of jpg – what would be better to use?

Thanks.

Louise

louise wrote:

In article <
server2.tampabay.rr.com>, says…

In article ,
louise wrote:

The original psd was 18,000 kb and the saved as copy jpg (with jpg options at their highest), is only a little over 2,000 kb.
How did 18,000 kb (because of Photoshop adjustments), turn (back?) into 2,000 kb?

That’s what JPEG does.

JPEG is a compressed format. A JPEG file will always be smaller than the original image because of this compression.

JPEG is "lossy" compression. That means in order to make the file smaller on disk, image information is discarded and the image is deliberately degraded in quality.

Why did you save as a JPEG? Is there some specific reason you had to use JPEG, instead of PSD or some other format? JPEG degrades quality; the JPEG format was invented for situations where file size is critical and image quality is not important. If you do not have a specific and good reason that you have to use JPEG and can’t use some other format, you should not save your images in JPEG.

It is my impression that not everyone can open a psd file. Is that true?

I see frequent complaints on these and the Adobe forums that recent versions of Photoshop have trouble opening PSDs (and of course older ones won’t necessarily open newer PSDs, etc, etc, and with 3rd party software all bets are off). You are probably wise to question if PSD is the best for your needs.

So, I used the best level of jpg – what would be better to use?

It all depends on who you need to open the file, and what for. If you’re publishing for the web, JPEG is fine (but a 3MB JPEG would be impractical).

If you’re passing on to a printer or someone who is going to manufacture an image, then you could consider a standard lossless format like TIFF.

So the question can’t be answered without considering ‘what for’ and ‘who’.

Thanks.

Louise

louise wrote:

It is my impression that not everyone can open a psd file. Is that true?

That depends on who you are sending it to and what they are going to use it for. Mailing around a funny picture to your friends would best be served with a jpeg, sending a picture to a printer would probably be ..psd, or the more generic tiff and eps formats.

Cheers,
Nicholas Sherlock

In article ,
louise wrote:

It is my impression that not everyone can open a psd file. Is that true?

Depends. Who are you sending it to? What are you using it for?

Most serious, professional programs intended for print can read a .PSD; if you are sending the image to someone else for viewing onscreen, you can use a format like .BMP.

So, I used the best level of jpg – what would be better to use?

What are you planning to do with the image?

—
Art, photography, shareware, polyamory, literature, kink: all at http://www.xeromag.com/franklin.html