I need bigger Jpegs from Tiffs

[ajohnw]

Given my usual simplistic initial approach to a problem like this I would give them jpg's that looked over 3 times wider than A4 on a PC screen which in most cases is 100 dpi. If not adjust size accordingly. I'm surprised Adobe don't allow the quality level to be specified directly. All of the software I use allows that to be adjusted as % up to 100% I believe but I usually use 95% in case I want to edit again but in real terms less than that would be ok even for that.. There is also a lossless jpg standard but that may put a limit on the incremental changes in size and it's still pretty efficient.

John
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[irlien]

Thanks John!

Yes, the Jpegs look huge when viewed in an ordinary image viewer, that's Preview on my Mac. I can view at actual pixel size and the objects look at least 3 times larger than print size.
I save them at maximum quality setting which is 12 on the Adobe scale. For this particular job, I had to use the Jpeg2000 format which gives double, sometimes treble the size of an ordinary Jpeg.
I'm still puzzled though. Capture One can process the RAWs as 13MB Jpegs, but that's no good as I want to edit in Tiff.
I just sent an email to the technical department at the PR company. It will be useful to have their exact specs and not the watered-down client instructions.

[ajohnw]

Some people I know do have problems with some publishers when they submit files but I don't think this applies in this case. They use dslr's and the publishers expect huge files from medium format cameras. It causes a fuss but eventually the publishers find some way of converting them. Maybe the customer has used some one like this at some point. I mentioned this problem to some one recently and it seems that when many pro's need to produce medium format they simply hire and pass the cost onto the customer. Might be of use to some body on here at some point in their career.

My PP skills are evolving but have had to edit jpg's as one package only accepted those. All it really means is that the raw conversion has to be done with more care. However when you save from adobe it will probably reduce the file size.

John
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[pnodrog]

It would be interesting to know the resulting jpeg file size if you photographed the jewellery on white linen or a background with a very subtle pattern. I think the file size would increase dramatically. A plain single colour background is ideal for jpeg to compress and produce a small file.

[Kodiak]

A plain single colour background is ideal for jpeg to compress and produce a small file.

Small file size at a quite hefty price: compression artefacts!

[xpatUSA]

Yes, the Jpegs look huge when viewed in an ordinary image viewer, that's Preview on my Mac. I can view at actual pixel size and the objects look at least 3 times larger than print size.

As has already been said, that is quite normal when any file has larger pixel dimensions than your screen and the view is set to 100%. For people who print, it is also normal for an image pixel size to be larger than your screen pixel size. However, buried inside any jpeg file is information about the file. That is called meta-data and is usually in the format specified as EXIF. Some the of the tags in the meta-data are to do with printing resolution:



You'll see units, usually inches, and the resolution in both width and height, normally (but not necessarily) the same. These values do not affect the image size as seen on your screen.

I save them at maximum quality setting which is 12 on the Adobe scale.

12 on the Adobe scale gives you what is known as 4:4:4 compression. What is less well known is that 9 also gives 4:4:4 compression and an almost as good image. For your purposes, you may find that a setting of 10 or 11 would meet your printer's need and give adequate image quality. Furthermore, in my version of photoshop elements, buried in the filter > noise > reduction menu there is a magic checkbox for reducing JPEG artifacts.

For this particular job, I had to use the Jpeg2000 format which gives double, sometimes treble the size of an ordinary Jpeg.

Can't comment on that, but I do wonder why.

I'm still puzzled though. Capture One can process the RAWs as 13MB Jpegs, but that's no good as I want to edit in Tiff.

I just sent an email to the technical department at the PR company. It will be useful to have their exact specs and not the watered-down client instructions.

Is there any way you could post those watered-down instructions? With all due respect, there could be a possibility of misinterpretation if they are not clear enough. For example:

My clients require 2MB jpegs @ 300dpi for print. Seems reasonable, right?

That sounds extremely unreasonable to me. The size of a JPEG can not be 'set' to 2MB. And the words 'at least' or 'no more than' or even 'approximately' do not appear. So, your clients' instructions are just a tad South of perfect

[pnodrog]

Small file size at a quite hefty price: compression artefacts!

I was not referring to a low quality jpeg setting but rather that even with a high quality setting the content is such that jpeg algorithm works very efficiently and results in a small file.

In the samples below the artifacts in the text if any will be the same but due to the other content the file sizes differ markedly.

343KB



209KB

[proseak]

"My clients require 2MB jpegs @ 300dpi for print."

What exactly have they said they want?

[dan marchant]

I'm still surprised by the size of my Save As Jpegs all the same. Could it be because they are very fine pieces of jewellery on white backgrounds, i.e. with little information in the file? Still, one particular Tiff measures 84MB and saves as a 1.8MB Jpeg.

This is almost certainly the case and easy to test. Save a JPEG then take the original TIFF and using Photoshop pen tool scribble random rubbish all over the white background. Do this multiple times with different colours so you no longer have large blocks of easy to compress single colour. Save the new image using the same JPEG export settings and compare the two files.