Ugly Hedgehog - Photography Forum
Home Active Topics Newest Pictures Search Login Register
Links and Resources
The pros and cons of shooting RAW versus JPEG
Page <<first <prev 5 of 14 next> last>>
Jul 14, 2021 10:13:04   #
Ysarex Loc: St. Louis
 
JD750 wrote:
Ok.. But wait. Demosaicing or rendering, combines the colors of adjacent pixels to get the three colors per pixel.

“A demosaicing (also de-mosaicing, demosaicking or debayering) algorithm is a digital image process used to reconstruct a full color image from the incomplete color samples output from an image sensor overlaid with a color filter array (CFA). It is also known as CFA interpolation or color reconstruction.”
https://en.m.wikipedia.org/wiki/Demosaicing

The information is all there it just has to be processed which is why you have more control over the raw result.

Look I’m not arguing for raw. I shoot jpeg a lot but I think it’s good to understand the differences.
Ok.. But wait. Demosaicing or rendering, combines... (show quote)


The information is not all there. The demosaicing process is transformative and creates information from the raw source. Different demosaicing algorithms will/can create substantially different end results. Photographers often prefer what they get from one raw converter versus another and a reason for that can be the demosaicing algorithm/algorithms used and how they create the RGB data from the raw source.

Reply
Jul 14, 2021 10:16:56   #
Longshadow Loc: Audubon, PA, United States
 
JD750 wrote:
The information is there you just have to do the math. Say you have two numbers, 5 and 3 and you do math to get the average of 4. The information was there, you just had to extract it. Which took some energy. So it wasn’t free.

And it’s a one way process because given 4, you can’t say for sure what the original two numbers were.

And that is how an image file is created from a raw file.

And that's why you can't go back.

Interpolation will provide something, but who knows if it's correct.
It surely won't be the "original" RAW.

Reply
Jul 14, 2021 10:17:12   #
Ysarex Loc: St. Louis
 
BigDaddy wrote:
No, not to you. I've determined a good while ago you are not worth the effort, any effort, imo.

As I suspected. Big mouth no show. You won't show us because you can't. You can't back up what you say because it's a pile of BS. With nothing to show you've got nothing to say.

Reply
 
 
Jul 14, 2021 10:19:55   #
BebuLamar
 
JD750 wrote:
The information is there you just have to do the math. Say you have two numbers, 5 and 3 and you do math to get the average of 4. The information was there, you just had to extract it. Which took some energy. So it wasn’t free.

And it’s a one way process because given 4, you can’t say for sure what the original two numbers were.

And that is how an image file is created from a raw file.


If you plot something and one second it's 3 and the next is 5 you can conclude that's between the 2 seconds it's 4 but you're not sure of that. Only that is very likely. It could jump from 3 to 6 then back down to 5.

Reply
Jul 14, 2021 10:23:07   #
Longshadow Loc: Audubon, PA, United States
 
BebuLamar wrote:
If you plot something and one second it's 3 and the next is 5 you can conclude that's between the 2 seconds it's 4 but you're not sure of that. Only that is very likely. It could jump from 3 to 6 then back down to 5.

Four numbers now, he was talking about two, and the same situation exists,
you can't tell the original players without a program.

Reply
Jul 14, 2021 10:24:52   #
BebuLamar
 
Ysarex wrote:
The information is not all there. The demosaicing process is transformative and creates information from the raw source. Different demosaicing algorithms will/can create substantially different end results. Photographers often prefer what they get from one raw converter versus another and a reason for that can be the demosaicing algorithm/algorithms used and how they create the RGB data from the raw source.


Similarity to upsizing. Some up sizing algorithm can create larger image with convincing details but the details weren't there.

Reply
Jul 14, 2021 10:59:31   #
BebuLamar
 
Longshadow wrote:
Four numbers now, he was talking about two, and the same situation exists,
you can't tell the original players without a program.


You only have the number 3 and 5 and you say the in between value is 4 by interpolation. It's very likely that in between the 3 and 5 it was 4 but it could be 6 or 100 for that matter. You can't be sure because you didn't sample it at that moment. Or in case of a imaging sensor you didn't sample that color at that location. You only know the color of the 2 adjacent locations.

Reply
 
 
Jul 14, 2021 11:22:46   #
Ysarex Loc: St. Louis
 
BigDaddy wrote:
I guess somebody might gives a rat's patootie what others do, but for me, my only interest is when the reasons given for doing one or the other is false....."You can't fix white balance in a jpg" is another one, there are plenty of them.

Well, given an opportunity to prove himself Big Daddy tucked his tail between his legs and ran. Here's the post where Big Daddy was given an opportunity to demonstrate his incompetence (yes there is a reason he won't try it ): https://www.uglyhedgehog.com/t-704155-2.html#12392006

So let's look at the issue. Raw data has no white balance set. That's one of the important steps in processing the raw data. Setting white balance for a raw file can be a simple singular step of sampling a gray point in the image like a gray square in a color checker or selecting a preset value like daylight/overcast or directly setting the temperature/tint values. With the raw file presented in the link above, what I did was sample the third from white gray step in the color checker gray scale -- done.

But a JPEG has already had the white balance set when it was processed in the camera. If you're trying to change that white balance then you're trying to set a new white balance on top of a pre-existing white balance. You won't get the same result as you would setting the WB in the raw file. Let's do the same thing with the camera's auto WB JPEG that I did with the raw file and sample the same gray step in the color checker. You can go back to the original post to look at those two images and see the camera autoWB JPEG.

Sampling the same gray step in the JPEG certainly makes that step gray and moves the overall white balance in the right direction. On first glance it seems to have worked. But then look closer and what you're going to find is pretty substantial discrepancies. Colors that didn't have to be altered too much come pretty close with the new WB for the JPEG. The JPEG autoWB was warm and the warm colors turned out better in the new WB. I guess if the subject were a gray wall Big Daddy would be right. Because we're trying to set a WB on top of a prior WB colors are not shifted the same amount from the same original position. I highlighted two pretty severe examples in the illustration below.

You can work with the color in a JPEG and you can seemingly shift the WB but you won't get identical or even close results to originally setting the WB in the raw file if the JPEG WB was substantially different to start. With the JPEG, after frustrating effort that ultimately requires you to start selecting and separately changing colors, you end up settling for something close at best to what a single mouse click produces when setting WB in a raw file.


(Download)

Reply
Jul 14, 2021 11:32:43   #
srt101fan
 
WOW!!! Trying to keep up with these multiple conversations but I don't understand most of it.....

And I think I'm getting pixelated......😕

Reply
Jul 14, 2021 11:39:28   #
johngault007 Loc: Florida Panhandle
 
All I got out of it was....All files are data files that either need interpreting or some sort of processing to view on a display (monitor)...lol

Reply
Jul 14, 2021 11:48:04   #
BebuLamar
 
johngault007 wrote:
All I got out of it was....All files are data files that either need interpreting or some sort of processing to view on a display (monitor)...lol


But the raw files contain only 1/3 of the data needed to display an image. That is the distinction between raw and other formats.

Reply
 
 
Jul 14, 2021 11:55:45   #
Longshadow Loc: Audubon, PA, United States
 
BebuLamar wrote:
You only have the number 3 and 5 and you say the in between value is 4 by interpolation. It's very likely that in between the 3 and 5 it was 4 but it could be 6 or 100 for that matter. You can't be sure because you didn't sample it at that moment. Or in case of a imaging sensor you didn't sample that color at that location. You only know the color of the 2 adjacent locations.

Yup, you got his point.
The "original" data cannot be recovered.

Reply
Jul 14, 2021 11:59:19   #
Longshadow Loc: Audubon, PA, United States
 
BebuLamar wrote:
But the raw files contain only 1/3 of the data needed to display an image. That is the distinction between raw and other formats.

But who's counting?
Not me.
Not a distinction I'm worried about.
I'm more concerned about what I can do with the data.

Reply
Jul 14, 2021 12:06:27   #
BebuLamar
 
Longshadow wrote:
But who's counting?
Not me.
Not a distinction I'm worried about.
I'm more concerned about what I can do with the data.


That is why the monochrome sensor of the same number of pixels deliver sharper image because there is no made up data.

Reply
Jul 14, 2021 12:06:44   #
johngault007 Loc: Florida Panhandle
 
BebuLamar wrote:
But the raw files contain only 1/3 of the data needed to display an image. That is the distinction between raw and other formats.


My comment has nothing to with how much data is coming from where. And I think LS was trying to explain that. From strictly a computer point of view...all files need some sort of interpretation to display. We just take for granted common file extensions are usually pre-loaded with an OS.


As far as the in-depth minutia of editors...I am thoroughly enjoying the discussion because that is something that this forum is very good at digging into.

Reply
Page <<first <prev 5 of 14 next> last>>
If you want to reply, then register here. Registration is free and your account is created instantly, so you can post right away.
Links and Resources
UglyHedgehog.com - Forum
Copyright 2011-2024 Ugly Hedgehog, Inc.