MCoomber Loc: Hamilton ontario

Hi there,

I have been shooting with a canon t3i - 18 mp. I have been using older manual nikkor lenses with great results of clarity, depth and dynamics. The only thing I find is when I bring them into PS/Lightroom, the files readout as over 300mg. Not sure why this. Any help would be great.

Linda From Maine Loc: Yakima, Washington

(edit) I shouldn't try to answer questions before breakfast! You are probably asking why the read-out is wrong, not why they "are" 300 mb :)

Sorry, don't know :oops:

SonyA580 Loc: FL in the winter & MN in the summer

May depend on how you have the camera set. Are you shooting RAW at maximum picture size and converting to .tiff? This produces huge files.

anotherview Loc: California

Presume you mean "mb" (for megabyte), and I presume you load your files in the TIFF file format. This format takes up more storage space due to large files.

Try setting your software for the Photoshop PSD file format. Then your files should load as 30 to 50mb.

Maybe others here will have a better answer.

amehta Loc: Boston

To get to 300MB, it has to be a TIFF file with layers. With a 36mp image, 16-bit TIFF, no compression, the file size is around 200MB. So you would have 3 layers to get that large. A single layer 16-bit TIFF would be about 108MB for you.

Rongnongno Loc: FL

Err... Using tiff is the only reason and... Saving raw is not only more efficient but also more accurate than a camera produced tiff...

amehta Loc: Boston

I don't see how this can happen with camera-produced tiffs.

Bill Houghton Loc: New York area

Sony hit the nail on the head. Sounds like a TIF for sure. Your importing CR2 and your converter is saving as TIF.

MCoomber Loc: Hamilton ontario

Thanks for your help. Ny files are tiff for some reason when I import from lightroom into ps.

Michael

Rongnongno Loc: FL

Think color depth.
A camera produced tiff is 8 bits because it goes through the Bayer layer. A raw is 11 to 14...

sloscheider Loc: Minnesota

Go into your LR Preferences. In the "External Editing" tab you can chools PSD as the default file format when stepping out to Photoshop.

Apaflo Loc: Anchorage, Alaska

Bayer Filter Encoded RAW files are more efficient, but not more accurate. Interpolation, or the insertion of calculated approximate values for missing data, is required to get an image from the raw sensor data. It is accurate enough, but nothing like as accurate as an RGB (three color) encoded image file.

Basically a 36MP RAW file specifies the approximate color and brightness of 36 MP, but a 36MP TIFF file specifies an exact color and brightness for 36MP. It takes 14 bit per pixel to be close enough, and at least 24 bits per pixel to be exact enough to print it, and maybe 48 bits per pixel to be exact enough to edit it.

Rongnongno Loc: FL

raw does not pass through the Bayer layer and because of that not have the 8 bit color depth limitation but 11 or 14.

Because tiff goes through the layer, its color depth is 8.

Color mode is something else altogether and NOT related to the color depth.

As to 'Bayer layer' being more accurate let me beg to differ. I am doing more important things that I need researching to point this out to you so, do some research and figure out why raw is so much more than any other format.

Apaflo Loc: Anchorage, Alaska

I'm not sure what you mean by "pass through the Bayer layer"? That isn't standard terminology.

While TIFF files use 8 or 16 bit depth, the actual color of a pixel requires three times as many bits to define. An 8-bit TIFF file contains 24 bits for the of color each pixel, while a 16-bit TIFF file uses 48 bits for each pixel.

With a TIFF file the accuracy is the same as the precision, because any given pixel value defines precisely one specific color, and the total number of colors is the same as the possible number of values.

With the mosaiced Bayer pattern in a RAW file the data for one pixel is not just that one 14 bit byte. It is derived from at least a 2x2 byte matrix and usually from a larger matrix. Hence the precision might be thought of as 4*14 (56) bits minimum, and commonly either a 3x3 matrix (126 bits) or a 4x4 matrix (224 bits) per pixel.

There is significantly greater precision in the raw sensor data. However, there are an infinite number of ways to demosaic the bits, each of which can very correctly produce a different color from the same matrix; and thus the value can be repeated with precision, but they do not represent an accurate color value!


What does "through the layer" mean? TIFF actually has nothing at all to do with derivation from raw sensor data.

Color in a TIFF file is encoded RGB data. The 8 bit color depth defines the precision of the color levels that along with the three 3 RGB channels specifies one single color to a very accurate and repeatable known value.

The difference is that the raw data provides only the approximation of an exact color, which by changing the interpolation algorithm it is possible to select, for any given pixel, a more precise color than can be done with TIFF. But the color produce at the output is not necessarily an accurate representation of the original input color.

TIFF accurately defines a color, but the increments between color variations are relatively larger.


Color encoded via a Bayer Color Filter Array is well known to produce an approximation of a color rather than an exact value. That is precisely the reason it is called "interpolation" when the data is converted to different type of color encoding.

MW

If you want to shrink those big .tif files in LR, there is a menu feature that will convert them to DNG. As far as I can tell you don't loose any resolution or color by doing so.