lmTrying wrote:
In my nine months on this forum, I have read a lot about post processing. I know a lot of you will say LR/PScc. That's not the question. I know I need to start with organizing and I may start with AfterShot. That's not the question either.
I need to really understand terms like the following: RAW, jpeg, Tiff, dng, dynamic range, HDR, and a whole lot of other things I can't bring to mind right now. Plus the processes of converting from one to another. Preparing to print, sending files over the internet, why one picture loads in a flash and another takes forever
I've seen a lot of suggested reading on composition. How about suggested reading on post processing in the camera and in the computer that explains the above information and more. At this point I'm just really confused due to the little bits I have pieced together but don't understand. A "how to" book on operating PS is not what I'm looking for. I don't assume to get to the level that many of you have attained, but I would like to truely be able to understand and follow your conversations and apply some of it to my own photo work.
Thanx up front.
In my nine months on this forum, I have read a lot... (
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Get Tony Northrup's books on Lightroom and Photoshop and Stunning Digital Photography. Get on Google and do a search for Glossary of Digital Photography by John Blair.
Meanwhile:
RAW files are unprocessed but digitized data from the sensor. They are analogous to unprocessed, exposed color film.
JPEG files are compressed images. They can be generated in your camera, or saved from post-processing software from raw (and other) file formats.
TIFF is a class of Tagged Image File Formats, and there are at least 49 flavors of them. They are all bitmapped images of varying bit depth.
A bitmap is a grid of pixels (picture elements). Pixels are just numbers representing color and brightness.
Bit depth is how many binary digits — powers of 2 — are used to create each of the colors in an image. An 8-bit per channel file has 256 shades of red, 256 shades of green, and 256 shades of blue, and can describe about 16.7 million colors.
The dng format is Adobe's public domain file format for storing raw files. They convert camera manufacturers' proprietary raw file formats to a common set of characteristics.
Dynamic range is the difference between the brightest and darkest tones a camera can store at a given ISO (sensitivity). In audio, dynamic range is the difference between the loudest and quietest parts of a signal. In both cases, DR is measured in decibels.
In photography, each f/stop of dynamic range is 3db. A dynamic range of 42 decibels can record about 14 stops of information between the noise in the signal and the brightest tones that can be recorded. Photo paper can reflect only about 5.5 stops of dynamic range in normally bright room light.
In audio, a 3db change makes a signal twice (+3db) or half (-3db) as *powerful.* A 10db change makes it twice or half as *loud,* "psychoacoustically."
HDR is a method of achieving "high dynamic range" in an image by combining the best of underexposed, normally exposed, and overexposed images together in software. Some snarky people make fun of it by calling it "High Definition Reality", since, if overdone, it looks UNREAL. (Gentle use of HDR techniques goes a long way!)