How to convert JPEG to RAW in Photoshop or similar?
I am having a competition in which I have to submit images in RAW format. But I have already clicked some images with Nikon D3200 in JPEG.
Is there any way to convert JPEG to RAW format in Photoshop or any other similar software.
RAW is not (or minimally) processed image data from camera sensor. JPEG is processed image data. Typically, raw-files from modern cameras have 12-14-bit per pixel which means up to 16384 values (for more details see Michael Clark's comment). JPEG can have only 256 luminance values per RGB channel. This means that jpeg contains much less data than a corresponding raw-file. So no, there is no way to convert a jpeg to raw.
Technically, it's possible of course to convert jpeg data format to raw data format (like it's possible to convert a jpg to png or gif) but this will not make a raw-file and the organizers of competition will surely see that it's not a true raw file. However i have never seen such a tool and doubt that any exists.
Alex S, thank you for in depth answer. I'll have to shoot those pictures again.
Raw files don't have 12-14-bits per color channel. They have a 12-14-bit monochromatic luminance value per pixel. Each pixel is filtered for *either* red, *or* green, *or* blue. When the raw file is demosaiced colors for each pixel are interpolated based on the monochromatic luminance values of adjacent pixels filtered for the other two colors as well as the luminance values of nearby pixels filtered for the same color as the pixel in question.
`JPEG can have only 256 luminance values per color.` This is also technically wrong. I think what you meant to say is "values per RGB channel", and even that depends on the standard/compression used.
@MichaelMauderer Before edit I already had used "channel" couple of times so I chose "color" to avoid repeating :) Updated now.
Great!. Sorry the last part of the comment wasn't clear, the exact number of values vary depending on the encoding, and is mostly unrelated to the RGB channels themselves.
@MichaelClark the exception is a Sigma camera with a Foveon sensor, it *does* capture all 3 channels at each pixel location. I'm sure you already knew but simply neglected to mention it :)
Are cameras with Foveon sensors even still being manufactured and sold new? Even if they are one would probably be safe to guess they comprise less than 1% of the world's camera population. ANd that's probably before you even count all of the cell phones, tablets, etc. with Bayer masked sensors.