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Possible concern over quality.


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Possible concern.

 

I have noticed something strange. When checking the image info on the back of my x100t the size of a RAF file in pixels its 1280x1920. If I develop this image into a tiff/psd the dimentions increase to 3264x4896. If I do the same exercise with a cr2 file from a Cannon the image starts at 5616x3744 and outputs to 5616x3744. So the file is being interperlated up. This must effect quality! Am I missing something..

 

 

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I understand that but within that data it must have an optimum size. As I said my Cannon raw file (data) has a dimension 5616x3744 = approx 21mb this is what I would expect. I was concerned that my x100t is showing a dimension (see screenshot) of 1920x1280 = approx 2.5mb not 16mb. Hence my concern. But as you say perhaps it's just jpeg for viewing within the camera. I'm not sure why I would need that information.

 

 

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I understand that but within that data it must have an optimum size.

The size of the RAW data is determined by the number of photodiodes. Fuji does not support compressed RAW files.

 

I am afraid that I don't understand your question ... is it about the RAW data, or the JPEG within that file?

 

 

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Sorry if I haven't explained myself. I didn't understand (based on the info on the back screen) why a raw files dimensions were only 1920x1280.

 

 

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Why would a RAW file have dimensions? It contains the readout of the photo cells. The RAW converter creates pixel data with a RGB value from combining the readout values (and knowledge about the colour matrix).

 

I think I am missing your question.

 

Edit:

http://www.cambridgeincolour.com/tutorials/raw-file-format.htm

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Okay why dose my Cannon raw file info give me a dimension of 5616x3744 and if I covert to a tiff the image is 5616x3744.

If a raw file has no dimension dose this mean I can output it to any size with on lose of quality. I wish.

 

 

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Okay why dose my Cannon raw file info give me a dimension of 5616x3744 and if I covert to a tiff the image is 5616x3744.

 

Because that is what your chosen RAW converter software does? Your software creates the picture, by doing a lot of operations on the RAW data.

 

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I understood a CCD is composed of an array of small sensors, each one is one pixel. It is arranged in rows and column. Each contain a photo diode sensor that capture the color and brightness and translate to a charge and store in the cap inside each pixel cell. This dater is then stored in a raw file.

 

 

 

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I don't know how I can put it any other way. I have two files one from a cannon and one from x100t. Each gives me a dimension in the info. Cannon 5616x3744 this is 21mb and that is what the chip size is. X100t dimension info (see pick previous) is 1920x1280 this is 2.5mb not 16mb. So my question was, is it being interperlated? Now if the dimensions on the screen are something else fine. I've lost interest now. But thanks for your patience.

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Really? Are the X100T *.RAF files only 2.5MB? That is weird.

 

I don't have a X100T to compare, but I would expect the files to be around 20MB indeed.

 

Edit: just checked for my X-E1, and they are 25MB ... I would expect about the same for the X100T.

 

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But how does the 1920x1280 image size relate to that 30MB file size then? That would be about 64 bits per pixel, right?

 

Sorry for being so thick, but I'm really not grasping your point :-(

 

Edit: do you mean that your RAW converter resizes the resulting image to 1920x1280 pixels?

 

Edit2: the info on the back of your camera relates to the JPEG data. It has no meaning for the data in your RAW file.

 

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A Google search reveals you are not alone ... it looks like the way the info is displayed on the back of the camera is misleading for many people.

 

Don't worry; whatever that info says, it does not affect the RAW data in your RAF file.

 

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You are confusing a lot of things.
 
First:
 

Sorry you misunderstand, what I'm saying is if you multiply the dimensions given in the info this gives you the mb size of the chip x100t is quoted as 16mb. The raf file is about 20 mb.


What you mean are MegaPixels. "MP". NOT "MB". "MB" means MegaBytes.
"mega" is just a prefix that means 1 Million or 106. I'm sure you know what a pixel is, although your Fujifilm camera has a cmos sensor, not a ccd sensor.

A byte is a unit of digital information, usually consisting of eight to ten bits, while a bit is defined the smallest piece of information in digital computing and can posess a value of either zero or one. The *.RAF files have a data size which is measured in MB.

Those two are not the same! (Although they have a relation, namely the bit depth of the analog-digital conversion multiplied by the number of pixels)

Second:
 

johant already tried to explain it to you, and I will try again. Digital files are often "containers", which combine several different types of information in one "file", that you can see and copy. Like the *.RAF files of fujifilm or the *.CR2 files of Canon. Those RAW containers consist of the RAW data that has been read from the sensor and converted from an analog signal to digital data, the exif-data (camera type, time of exposure, lens, shutter speed and such), and often a small (or big) *.jpeg file, that is included into the RAW file, which makes it possible to "see" what is in the RAW file. This embedded *.jpeg in your RAW file has probably a size of 1920x1280 (2.5 MegaPixels). The embedded *.jpeg in Canon RAW files is usually about 3 MegaPixels.

So I suppose, the software you use, or your camera (you did not tell us what exactly tells you the "size" of your files) shows the dimensions of the *.CR2 RAW data, but the dimensions of the *.RAF embedded *.jpeg.

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  • 4 weeks later...

Very basic explanation.

 

 

When you shoot in RAW-only a low-res JPG actually gets created too for faster previewing.

This gets embedded into the RAW file. The low res jpeg is 1920x1080pixels in resolution. 

 

You'll see this when you try to zoom to 100% to preview your image on the camera. You won't actually be able to view 1:1.

 

If you set your camera to shoot JPG+RAW you'll be able to zoom 1:1. and you won't get the misleading dimension read out.

 

Try it shooting in RAW only and then RAW+FINE. You'll notice the files are definitely both 16MP :)

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