Converting Tiff files to JPEG without changing size or Res.

[J.D.]

I need a 48MB uncompressed min. JPEG. in 300ppi. Can I achieve this from a large TIFF using CS6?

 

[KmH]

There is no such thing as an uncompressed JPEG, and the PPI setting (print size resolution) has no effect on the image file size.

You control the file size of the TIFF to JPEG conversion by adjusting the Quality slider in the Save As dialog box
12 is the maximum setting and applies the ;least amount of compression in the TIFF to JPEG conversion process.

However, you will basically need a 4x larger TIFF file to start with if you want a JPEG that is 48 Mb.

 

[The_Traveler]

Maybe.
This kind of specification usually comes from an art director who doesn't understand photography.
What are the dimension of the file in pixels?
If you save the file as highest quality - and it is too small in megabytes you might have to upsize it using PS to get the size they want.

For example - if a file is 3872 x 2592, saved at max quality is 5.418 Meg, upsized to 6000 on the long side, about 8.60, upsized to 12000 about 20 meg,
so it looks like about 20000 on the long side will give you a jpeg of ~33 meg.

but check if they really want a 33 meg jpeg

 

[runnah]

I have submitted hundreds of documents for print and other formats and have NEVER heard of a minimum MB file size.

Seems to me like Lew mentioned that the person requesting the file has no idea what they are talking about.

The only things that matter to vendors are pixel dimensions, color space and file format. Some may have a maximum file size limit.

 

[Derrel]

I "think" what the OP means is a JPEG file that, when OPENED, and therefore "uncompressed", is 48 megabytes in size. Maybe not, but that was whjat I understood the originaL request to be. I have spoken English my whole life, and on many occasions I have heard the above types of expression. Like, "The JPEGS when uncompressed in Photoshop open up to be 48 megabytes". Similarly, I have heard the question, "How big do the files open up in Photoshop." That question used to be very common in the early days of digital imaging, but now, now that we have 2- and 3- and 4-terabyte sized drives, and cameras have insane MP counts, we don't hear much concern about such things.