Tips for those of you who shoot in RAW mode

07/11/2005 11:37:11 PM · #51

Originally posted by kirbic:

If you have a 10-bit resolution, you have 1024 possible unique values. Add one bit, you now double that to 2048. So by adding one bit of resolution you've added 1024 possible levels.

Yes, what you state is true. And ... irrelevant to the discussion of "which end of the string of bits holds the most data".

It doesn't matter if you add that one bit to the top of the string of bits or to the bottom. You still double the total number of values.

The theory that started this thread stated that there were MORE VALUES at the top end of the range than at the bottom. That is what I am saying is false.

Now ... as to the physics of light and whether a bit holds more "valuable data" on one end or the other... wow, I have no idea. But I'm guessing that a bit-is-a-bit. It can only hold a bit's worth of data.

Canon RF 24-70mm f/2.8 L IS

07/11/2005 11:53:27 PM · #52

Originally posted by deapee:

Anyway...I see a lot of people promoting RAW as a 'band-aid' to correct your white balance issues or exposure issues and that's a foolish reason to shoot RAW in the first place. Learn to shoot properly in the first place, and you will become a better photographer.

I do remember you asking the other day for info on how to fix your photoshop because it was no longer opening your NEF files ;). But you're right - it would be ideal to get everything right the first time. But I'd rather not custom WB (for ultimate control) everytime I walk indoors/outdoors/into the shade/etc.. and the whole selecting a white and gray point via curves is much more tedious to me than sliding the little bar back and forth.

Granted, I could get a larger # of my shots processed faster.. but that's an okay tradeoff for me at this point in order to be able to fully process my 'favorite' shots. Once something has been processed in camera, there might be some turning back - but, there almost might not be. And perhaps it's just me, but the saturation, contrast and [especially] sharpening effects in C1 are much more attractive to me than the same effects in Photoshop. It could be because I'm doing them wrong in Photoshop, but it keeps me happy nonetheless.

kirbic

Canon EOS R5

07/11/2005 11:55:12 PM · #53

Originally posted by dwterry:

Originally posted by kirbic:
If you have a 10-bit resolution, you have 1024 possible unique values. Add one bit, you now double that to 2048. So by adding one bit of resolution you've added 1024 possible levels.

Yes, what you state is true. And ... irrelevant to the discussion of "which end of the string of bits holds the most data".

It doesn't matter if you add that one bit to the top of the string of bits or to the bottom. You still double the total number of values.

The theory that started this thread stated that there were MORE VALUES at the top end of the range than at the bottom. That is what I am saying is false.

Now ... as to the physics of light and whether a bit holds more "valuable data" on one end or the other... wow, I have no idea. But I'm guessing that a bit-is-a-bit. It can only hold a bit's worth of data.

I think we're kinda on the same page, tho maybe in a different paragraph...
I agree completely with your conclusion that it does not matter to where the bit is added. for a given number of bits, there are a set number of possible unique values, given by 2^n, where n is the number of bits.
Please take it as truth when I state that charge (that is, electrons) accumulate in linear proportion to the number of photons falling on a given photosite during the exposure time. This implies that unless some non-linear transform is applied in the analog electronics prior to digitization, that the RAW file still represents a linear reading of the analog data. This is in fact the case for all DSLRs that I am aware of. Gamma (the non-linear part) is applied in RAW conversion.
Assuming that this is the case, then the originally-stated premise is correct, and half the values are used for the brightest 1 stop of dynamic range.

dwterry

Canon EOS-1D Mark III

Nikon AF Zoom-Nikkor 70-200mm f/2.8 VR DG IF-ED

07/12/2005 12:09:55 AM · #54

Originally posted by kirbic:

Assuming that this is the case, then the originally-stated premise is correct, and half the values are used for the brightest 1 stop of dynamic range.

Okay, I can accept that the data can be quantized such that the top half might cover a wider gamut of light.

I just don't buy the number theory that was proposed! :-)

Message edited by author 2005-07-12 00:10:28.

Pedro

Nikon D200

07/12/2005 01:17:06 AM · #55

@ DW - I think of greater importance to the average non-binary-brained-shmoe (such as myself, who has actively resisted such things likely to spite my cobol-fortran-programming-since-the 70's father) is the practical part of this issue. in other words: what the hell does this mean to my photos at the end of the day?

While you're correct in saying that you're as likely to blow detail in highlights as you are to lose them in shadows, the former is infinitely less noisy and easier to fix at the end of the day. Exposing to the right (which is where this all began) will ultimately make cleaner images.

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07/12/2005 01:17:59 AM · #56

Originally posted by brianlh:

Your Auto WB should get you VERY close more than 90% of the time (from everything I have read).
Using a WhiBal card is AWESOME, also. No jacking with the slider. Hold it up, shoot it, ACR, select the WB tool...Presto!! Or you can just make sure that something is neutral grey in every shot, oruse something you know was white, then adjust the slider just a tad.

07/12/2005 01:56:13 AM · #57

Originally posted by dacrazyrn:

Could be - but I've also had very yellow or red images at times that I wish I could've fixed with the slider. Are you referring to fixing it in RAW still though? That's what I'm guessing ACR stands for, but a little confused.. I didn't know there was a custom white balance option there (to import an image taken under the same settings).

What about for JPEGs? - if there was something similar for white balance (which I'm extremely forgetful about), I would probably sacrifice the rest of the raw advantages for the added # of shots and less 'stress' on the buffer.

07/12/2005 02:06:12 AM · #58

Yes I was talking in RAW...WHIBAL Cards. which will work with jpg also with this action I have.
Depending on what image processor you are using, you can for jpeg. I set up an action in PS.
If the processor has a Color Sampler tool (one that you can choose at least three different areas) you can select a black, white, and neutral grey area. If you have PS, I can give ya the whole run down, and throw the action up on my website download area.

yes there is a WB in the Adobe Camera RAW convertor. Top left Eyedropper looking tool.

07/12/2005 02:35:40 AM · #59

I'd be interested in hearing more about the action for PS. If I can shoot casual pics of friends/family without going through the whole RAW deal, that could be a bit more convenient at times (though batch processing in RSE or C1 is a breeze).

07/12/2005 03:12:45 AM · #60

You can go here and download it. Has a lengthy explanation there also.
//www.photos4aidan.com/html/modules.php?name=Downloads&d_op=viewdownload&cid=6

This action simply runs through Levels and Curves automatically, using the presets of levels.alv and curves.acv (they load these. The process involves selecting, with the Color Sampler Tool (eyedropper with target), three areas (known white, black, and neutral gray). You then open Levels and adjust the red, green, and blue levels for the black and the white selections. These numbers show up in the Info box. You want to adjust each color point so that they all match (exactly is preferred) IN THE INFO box, not the adjustment box. IE: R-253, G-253, B-253, and then do the same with the black point. Then Save this as levels.alv and ok or cancel. Go to Curves (I load the last one so my points show up). Look in the info box...add the three (RGB numbers) together and divide by 3. Go to each color individually,make a point anywhere on the line, plug in the BEFORE number on the left side in the Info box for Input and your averaged number for Output. Do this for each color. Save this as curves.acv. Ok or cancel. Close the image. Run the Batch for all images shot in the same light. Sounds like a lot, but do it once or twice and it gets real easy. Otherwise do Auto-Levels. hehehehe

07/12/2005 04:09:24 AM · #61

You're right - it does sound rather complicated.. but I'll be sure to give it a go when I upload a set of jpeg shots. Thanks for the info/link :)

Nikon AF Nikkor 50mm f/1.8D

07/12/2005 06:01:52 AM · #62

No Problem

deapee

Kodak V803

07/12/2005 08:13:29 AM · #63

Originally posted by brianlh:

I do remember you asking the other day for info on how to fix your photoshop because it was no longer opening your NEF files ;).

You're right. Just because I don't agree with something, doesn't mean I shouldn't learn how to do it. There are rare occasions where I will use RAW to conduct some sort of experiment or test a theory...but like I said, promoting it as a bandaid to fix white balance issues or exposure problems is not what RAW was intended for. Learn how to shoot first.

dahkota

Canon EOS-7D

Canon EF 17-40mm f/4.0L USM

07/12/2005 08:43:12 AM · #64

My jpegs look fine out of camera. Some times the white balance is a little too high on the warm side for me, but I'm pretty good at exposure after 20 years of doing it. However, to my eyes, JPEGs don't have the depth of RAW. Maybe its just an illusion on my system with my camera, maybe not. I cannot get a JPEG as close to my reality as I can a RAW file.
Learning digital has been difficult in some respects. The images often don't look the same (as film) after you snap the shutter (not better, not worse, just different). RAW allows me to get my digital images closer to what I saw with film. So I use it. Not as a bandaid, as a way to replicate what I see.

D

dwoolridge

07/12/2005 09:18:52 AM · #65

Originally posted by deapee:

...but like I said, promoting it as a bandaid to fix white balance issues or exposure problems is not what RAW was intended for. Learn how to shoot first.

You appear to be missing the point. Learn how to read first.

Message edited by author 2005-07-12 09:19:29.

Falc

Canon EOS-1D Mark III

Canon EF 16-35mm f/2.8L USM

07/12/2005 09:23:57 AM · #66

Wooooh what a read, my head hurts. Bits, bytes, electrons and such all sounds mighty good, but most went sailing over my head.

However I ALWAYS shoot -1/2 to -1/3 underexposed (left side bias) and I was getting very pissed off with the noise in my images when converted from RAW. Now I have a possible answer which I can go away and experiment with.

If this works then you probably saved me the cost of a new camera body cos boy was I getting pissed and was convinced the cam had something wrong with it or that Rawshooter was screwing stuff.

I'll report back when I've experimented a little.

bbower1956

Canon EOS Rebel T6s

Canon EF 70-200mm f/2.8L IS USM

07/12/2005 09:39:35 AM · #67

There are 01 types of people in this world, the ones that understand binary and those that don't.

Edit: Should have been 10 - the fingers I am using are too fat.

Message edited by author 2005-07-12 10:14:44.

Uusilehto

Carl Zeiss 35mm f2.4 Jena/Flektogon MC

07/12/2005 09:45:53 AM · #68

Originally posted by Alienyst:

Oh well...a big let down...Raw Shooter Essentials does not run on my system. It loads, it boots, it crashes and burns. Why does everything need XP or, even worse, 2000? Also it requires IE6 which I don't have installed and no amount of money could convince me to install it either. Same problem I have with the Digital Professional Pro that came with the camera - needs XP. I can't use XP at home since it will not allow me to connect to the internet using a cable modem. I am not the only one, no one in my area can use XP and a cable modem and Microsoft doesn't seem to care either. No fix that I have ever found. In fact it was such a big deal around here it was in the papers for two weeks daily.

So I am back to jpg and never even left.

I switched to 2k from XP and never going back! Works fine on my comp, and i have IE5 (Not that i'd ever use it). Everything works bloody well. Best damn freeware RAW processer!

RAW all the way

oh, and

Originally posted by bbower1956:

There are 01 types of people in this world, the ones that understand binary and those that don't.

Classic!

cpanaioti

Canon EOS-40D

Canon EF 70-300mm f/4.5-5.6 DO IS USM

07/12/2005 09:51:13 AM · #69

I'm using XP with a cable modem at home without issue. Maybe XP doesn't have a default driver for the modem but then your cable company should be providing a CD with the proper driver for the modem they are using.

If jpeg is working for you then go for it.

Uusilehto

Carl Zeiss 35mm f2.4 Jena/Flektogon MC

07/12/2005 10:03:07 AM · #70

Originally posted by Falc:

However I ALWAYS shoot -1/2 to -1/3 underexposed (left side bias) and I was getting very pissed off with the noise in my images when converted from RAW. Now I have a possible answer which I can go away and experiment with.

Tell me about it! I've ruined an arseload of photos with that. Gotta thank the people who wrote this thread. Somehow i've never heard about this trick

thatcloudthere

Canon EF 16-35mm f/2.8L USM

07/12/2005 10:08:03 AM · #71

Originally posted by bbower1956:

There are 01 types of people in this world, the ones that understand binary and those that don't.

Actually, I've heard that there are 10 types of people in the world...those that understand binary and those that don't.

Unless your version of the joke takes the irony a bit further, I guess!
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thatcloudthere