RICARDOOO Loc: Findlay, Ohio

If I have a JPEG image and save it as a PSD file am I improving it in some way or am I just fooling myself???

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

The answer is - it depends.

If you are editing the image and creating layers, it is only one of two choices, you can also use tif.

If you are simply trying to add back what was taken away by in camera processing - it ain't gonna happen.

Better to take the image as a 12 or 14 bit raw file, and convert to 16 bit tif or psd, using ProPhoto color space, if you really want to preserve fine detail, maximize dynamic range, and have a better editing experience. Use jpg as a final output format- it is small, lossy, and generally lower quality than 16 bit tif, but usually suffient as an output format - once all the tone and color decisions have been finalized. It is not a file format that you want to begin your editing with.

kymarto Loc: Portland OR and Milan Italy

The answer is that you will not lose any more if you edit and resave.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

Or even if you open and save, without editing.

Rongnongno Loc: FL

As stated by another UHHer, you prevent the loss when working and saving the file.

If you change the color mode to 16 bits, you do not create 'new color shades out of nowhere'. just the potential. That was also correct but there is a caveat: Every transformation you make will influence the over all and shades that were not there are created on the fly through software interpolation*. These shades are not of the quality of the one existing in a raw* file but it is a start. A JPG treated this ways will always result in better noticeable results.

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* A raw file of 12 or 14 bits has gaping holes, same as a JPG as it is 4 (+12) to 2(+14) bits short from being 16 bits.

RICARDOOO Loc: Findlay, Ohio

So I would gain something in not loosing any more when it is opened and close...thanks

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

You sound like a politician. Opening and closing a jpg file won't change a thing. Opening and saving will. With a psd you will gain the ability to work in layers, but you will not gain any intrinsic improvement in image quality, except for the edits you create in the layers and any other image enhancements you apply.

Bottom line, you want to use a 16 bit, large color space workflow from capture to final edit, and save the 8 bit, sRGB jpg for output, and distribution, which is what it was intended for.

RICARDOOO Loc: Findlay, Ohio

Got it! But I am not a politician...ha ha ha :)

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

:XD:

Apaflo Loc: Anchorage, Alaska

Actually a Bayer CFA encoded RAW file uses far more bits per pixel to determine color than do 8 bit or 16 bit depth RGB encoded formats.

An RGB format (TIFF or JPEG) uses a 1x3 matrix to determine color. For an 8 bit file that is 24 bits per pixel. 2^24 = 16.7 million color values. For a 16 bit file that is 48 bits per pixel, or some 2.8e+14 color values.

But RAW files use a minimum of a 3x3 matrix (and it is usually larger). Hence a 12 bit RAW file uses 108 bits per pixel, and a 14 bit RAW uses 126 bits per pixel minimum. Even the 12 bit RAW file uses more than twice as many bits as a 16 bit TIFF!

A 14 bit RAW file has a potential for 8.5e+37 different colors! Not only are there no gaps, but between each color in a 16 bit depth RGB file that RAW might be able to put some 100 billion trillion times as many different colors as the RGB file can define totally!

There is a gapping hole in the 16-bit file! :-)

doduce Loc: Holly Springs NC

So let me toss in another format--DNG. I shoot in RAW and save in DNG. If I'm saving the images I've edited, which, among TIFF, PSD and DNG, is "best" format in which to save the final. Is the answer any different if I save works in progress, knowing that I will likely come back to the image and do more editing.

Interesting discussion.