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Old Apr 7, 2005, 6:47 PM   #1
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what is the best to use for wildlife jpeg or raw I have a D70 with a 80-400 vr
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Old Apr 8, 2005, 3:09 AM   #2
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http://www.luminous-landscape.com/tu...aw-files.shtml

http://www.luminous-landscape.com/es...awtruth1.shtml

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Old Apr 19, 2005, 6:55 PM   #3
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Hi Isager: Let me offer another link: http://www.kenrockwell.com/tech/raw.htm

Good luck in your shots.

Steve R.
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Old Apr 19, 2005, 7:16 PM   #4
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thnx for the help:-)
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Old May 9, 2005, 7:15 PM   #5
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Thanks for the links to the excellent articles regarding the [possible] benefits of using RAW image data... it all makes much more sense now. I do however have some, related, questions which I hope someone may be able to answer.

The articles mention that the CCD captures images with 12 (or more) bits per channel and that this extra colour resolution is contained in the RAW image data.
However the maximum colour depth I have ever seen (on a Windows PC) is 32 bits. This would equate to only 10 bits per channel maximum that can be displayed on screen (well, 10.6 actually but 0.6 of a bit is nonsensical)

(Actually, doing a little checking it would seem that even 32bit colour depth is not possible under Windoze... it is only 24bit colour depth with the fourth byte either discarded or used for something else, depending on which article I read)

Now I understand that if someone is going to go to the trouble of using RAW then it is most likely that they are planning to print the image rather than just view it on screen, but they still need to be able to see it on screen while they are getting it looking the way they want prior to printing. It is here that I fail to see how this extra colour depth would be much advantage. Although I guess that 1024 levels is still better that 256, maybe I would just be being greedy to want all 4096+ levels.

My question is this.
Am I completely misunderstanding things here, and if so can someone explain to me how it actually works?
Alternatively, are there video cards which give greater colour depth capability?
What is the maximum colour depth of the Mac?
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Old May 10, 2005, 4:52 AM   #6
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As far as I am aware most printers are only 8 bit per channel and as you say screens don't show the 12 bits per channel you get with RAW. It's more about what you discard and whether you make that choice or the camera. If you capture in 12 bit RAW and then post process in PhotoShop you may make changes that cause PS to adjust the data. For example I often use levels to improve the contrast. To do this I move the left slider in to darken the shadows and I may move in the right slider to lift the highlights. If I do this in 8 bit mode then I reduce my data point from 256 and PS has to interpolate the missing data. If I do it in 12 bit then the same thing happens but PS has more data to work with and if I then convert this to 8 bit then I hopefully end up with a better end result than if I'd started of in 8 bit and made the same changes. If I shoot in 8 bit the sensor still records 12 bit and the camera software not me make the choice on what to keep when converting to 8 bit.
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Old May 10, 2005, 2:37 PM   #7
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Well, I've shot RAW with my Canon 20D versus JPEG FINE, and the difference post-production after I saved it to a JPEG format was so minute that I decided it wasn't worth the extra effort.

-- Terry
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Old May 17, 2005, 3:28 AM   #8
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One thing I'm finding with my RAW v JPG is that my laptop really isn't fast enough to do proper Photoshop work on RAW images.

The RAW image imports as 40MB, then you do a bit of sharpening , add a couple of adjustment layers and before you know it you're up to 300MB per image.

The RAM on my laptop is maxed out at 1GB but the hard disk is still being used for the undo history so it's really slow.

A max res JPG opens into a file of around 20MB, so all adjustments really do seem to run twice as fast, perhaps more. Perhaps when I get a nice new 64-bit dual-core desktop with RAID 0 disks and 4GB of RAM I'll go back to RAW, but for now I'm defaulting to JPG and only shooting RAW when I think I'm going to need to do some serious post-processing.
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Old May 17, 2005, 4:43 AM   #9
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The reason the JPG is 20Mb and the RAW is 40Mb is that the JPG is 8 bit the RAW is 16 bit. Once you've done your initial processing on the RAW file you can change the mode from 16 bit to 8 bit and the file size will half. At this point you are throwing away some data but if you do your level or curve adjustments first you have got the benefit of the extra bits.




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Old May 17, 2005, 7:22 AM   #10
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I think the problem is that with RAW you are really saving your file in a proprietary format that might cause problems in the future. As we saw with the recent concern over Nikon's decision to encrypt part of their RAW data, this made certain 3rd party software unable to read the format. It took sometime before a workaround (a crack actually) was developed to allow the new files to be read.

With JPEG you have no such problems. The file format doesn't belong to any specific manufacturer and it is not hardware dependent.

While many people like to claim that RAW has more of this and that compared to JPEG...in the end, if you want to post your pictures on a site like this...you are going to convert to JPEG and then...where do all the extra bits go?

Also, many people like to take their memory cards to the new printing kiosks that are appearing everywhere...those machines are NOT going to be able to read your RAW files and, in any case, the idea is that you are going to play around with the file...tweaking this and that...reinventing the wheel with every shot and then printing it yourself. Some people like that...for some people that tweaking IS their hobby (taking the actual picture is secondary). Fine for them! Personally, it is a waste of my time...I always prefer to be out, taking pictures, rather than being stuck inside, in front of the computer, adjusting color gamut and tone curves. To each his own, I suppose!
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