JPEGs OK as Final Art in InDesign CS3?

[jetspank]

This may be a dumb question, and it's possible it's been asked before (though I did multiple searches on the forum and couldn't find anything), but does image quality suffer if you use jpegs as opposed to tifs as final art in an InDesign CS3 layout?

We produce a large number of magazines and therefore process hundreds of images per week. Most come from stock agencies or are commissioned by us, and virtually all are supplied as hi-res jpegs. We have traditionally changed these to tifs for placement in the page layouts, but I am wondering if that is truly necessary any more with CS3?

By the way, all of our pages are supplied to our print vendors as PDFX1a.

Adobe's Help Resource Center says this: "JPEG can be used for both online and commercially printed documents; work with your prepress service provider to preserve JPEG quality in printing."

Bottom line is we could save a fair amount of time if we didn't have to convert all our images from jpeg to tif. Anybody have any experience with this, or any thoughts?

Thanks!

 

[Rob Robinson]

Re: JPEGs OK as Final Art in InDesign CS3?

I don't think that's a dumb question, I've wondered that myself, coming from the olden days when jpg was not supported by layout applications. I would think that processing the file, already encoded with jpg compression, wouldn't be any different from a tif or eps that was at one time a jpg. Resaving a jpg as a jpg again is where you'd run into quality loss...

 

[doubting_thomas]

Re: JPEGs OK as Final Art in InDesign CS3?

I've used JPEGs many times. I don't have any issues with them as long as the resolution
is high and the color space is correct. ID CS3 supports them just fine as far as I can tell.

 

[Franknater]

Re: JPEGs OK as Final Art in InDesign CS3?

I wouldn't leave Adobe as being the final judge on this one. After all, CS, CS2, CS3 really can't be interchangeable with 100%accuracy, 100% of the time.

Our workflow (mine) is if JPEG is saved and provided with Maximum High Quality, we'll use them as JPEG. However, we will not save and export as JPEG, or change any files from TIFF to JPEG.

It only takes one time to be burned. Sure, there's been some compatibility fixes, but we've heard that before.

In software fixes, you may fix one problem then create two more elsewhere.

Frank

 

[bluskool]

Re: JPEGs OK as Final Art in InDesign CS3?

If you do not need to do anything to the pictures, keep them as jpeg. Opening them and saving them as a tiff will not do anything to the picture at all as you cannot add any quality to an image. In other words tiff doesn't make your image any better, it just doesn't make it any worse.

However, if you have to resize or alter the image in any way and you want maximum quality, save it as a tiff. Every time you open a jpeg and re-save it, you are loosing information from the image. For this reason, in prepress, we save as a tiff. There are no images that I open that I don't have to resize and color separate at the very least.

Will you notice a difference by saving as a jpeg, almost certainly not the first time, but if the images are going to be used and altered again, the jpeg compression will start to become more and more obvious.

For me, I will always save as a tiff because I always have to edit (all editing causes information loss) and I don't want to loose any more information and the size of the file is irrelevant to me , but if you do not need to do any adjustments or edits, then you are wasting time by opening and saving as a tiff.

Dan R.

 

[Tech]

Re: JPEGs OK as Final Art in InDesign CS3?

> {quote:title= wrote:}{quote}
> This may be a dumb question, and it's possible it's been asked before (though I did multiple searches on the forum and couldn't find anything), but does image quality suffer if you use jpegs as opposed to tifs as final art in an InDesign CS3 layout?
>
> We produce a large number of magazines and therefore process hundreds of images per week. Most come from stock agencies or are commissioned by us, and virtually all are supplied as hi-res jpegs. We have traditionally changed these to tifs for placement in the page layouts, but I am wondering if that is truly necessary any more with CS3?
>
> By the way, all of our pages are supplied to our print vendors as PDFX1a.
>
> Adobe's Help Resource Center says this: "JPEG can be used for both online and commercially printed documents; work with your prepress service provider to preserve JPEG quality in printing."
>
> Bottom line is we could save a fair amount of time if we didn't have to convert all our images from jpeg to tif. Anybody have any experience with this, or any thoughts?
>
> Thanks!


Hi Scott,
I think the key for your workflow is PDFX1a. Correct me if I'm wrong but this format should automatically compress and convert all your images to high-res JPEG format and downsample too 300ppi as well.

So in your case, if you are already receiving hi-res jpegs @300ppi with correct dimensions and not the annoying 72ppi (40"x30" or whatever digital size) then I would agree on leaving files as is.

Our files are often modify, so TIFF is still best for our workflow. Nor do I use any compression or downsample in our PDF setting.

 

[leonardr]

Re: JPEGs OK as Final Art in InDesign CS3?

PDF/X-1a (nor any of the PDF/X standards) does NOT SAY ANYTHING about image
resolution or compression choices.

A PDF/A file can have 72dpi images with JPEG _OR_ 1200dpi with no
compression at all and both would be valid.

Leonard

 

[rich apollo]

Re: JPEGs OK as Final Art in InDesign CS3?

JPEG compression can behave badly with CMYK color spaces. I've seen JPEG compression cause a scum dot in white areas of CMYK images.

Plus, every time you open, edit, and save you have to specify the JPEG compression settings all over again.

I've also had issues with artifacts being visible on press (especially with stochastic screening).

JPEG2000 is supposed to be lossless, but I've had problems getting RIPs to accept it. I avoid JPEG as much as possible, including in the creation of PDFs.

rich

 

[Tech]

Re: JPEGs OK as Final Art in InDesign CS3?

> {quote:title=leonardr wrote:}{quote}
> PDF/X-1a (nor any of the PDF/X standards) does NOT SAY ANYTHING about image
> resolution or compression choices.
>
> A PDF/A file can have 72dpi images with JPEG _OR_ 1200dpi with no
> compression at all and both would be valid.
>
> Leonard



Hi Leonard,
Last time I checked, Adobe CS3's default setting for PDF/X-1 (or any PDF/X) DOES auto JPEG compression and bicubic downsampling. Of course, one can change those default setting manually.

 

[leonardr]

Re: JPEGs OK as Final Art in InDesign CS3?

Funny this should come up this week. I just finished reviewing an ISO
Technical Specification (12033) on " Guidance for selection of document
image compression methods".

As described there, it's not appropriate to disregard JPEG (or other lossy
algorithms) simply because they are lossy. One needs to consider what type
of loss is involved, what level of loss would be acceptable and then
consider the choices to address that.

For example, while JPEG is completely unacceptable for text and vector
content (due to the artifacting that takes place with the DCT algorithm), it
is quite acceptable for photographs (which is what it was only intended for
in the first place) that are to be viewed strictly by humans.

Leonard

 

[bluskool]

Re: JPEGs OK as Final Art in InDesign CS3?

Yes, but this is situational. If you are in a situation where a photograph has the potential to be opened and resaved again and again, it will be compressed again every time. It won't take much to end up with visible artifacts. Also, if, as is the case with us, you receive a lot of submitted photos already compressed, I think it is best to not compress it further with DCT. I can see, however, that there are certain controlled situations where jpeg would be acceptable.

Dan R.