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07/08/2005 10:30:48 PM · #26 |
| But what about shooting strongly backlit subjects or shooting against an overcast sky? Does exposing to the right also apply in those situations? |
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07/11/2005 07:33:25 PM · #27 |
Originally posted by aquiz:
But what about shooting strongly backlit subjects or shooting against an overcast sky? Does exposing to the right also apply in those situations? |
Yes, it does apply here as well, but be careful not to blow your highlights especially in these situations.
I made some test shots last night, and even using ISO 1600 2 stops overexposed compared to ISO 100 1 stop underexposed, the ISO 1600 was a several times cleaner shot with amazing details... This is really amazing. |
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07/11/2005 07:40:30 PM · #28 |
Originally posted by aquiz:
But what about shooting strongly backlit subjects or shooting against an overcast sky? Does exposing to the right also apply in those situations? |
As Sonda posted, it does apply. The right side of the histogram will represent the brightest parts of the image, in this case the sky. Push it all the way to the right, but just short of blowing it out (if shooting RAW, you can "blow" the highlights on the in-camera histogram a little, up to 1 stop is usually recoverable if the highlights are neutral color. You need to learn where the limits are, through experience.
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07/11/2005 07:47:23 PM · #29 |
I seem to be confused a lot tonight. I know and have heard many people say it is better to shoot in RAW mode. I have tried this and have been way less than satisfied with the pics that are the result and the only thing I have to edit them is the 20D viewer utility which does not do much. Why is RAW better? More image data? So what, the image looks like crap and if it looks that bad it is going to be post-processed anyway or tossed.
Also, the problem of converting and processing. As I said all I have is the viewer thing that came with the cam. I cannot use the Digital Professional software that came with it. After doing what I could with what I have in RAW and converting to TIFF to go further, the image looked even worse. I shoot in jpeg and my images look better, cripser, more colorful, at least to me. So what is the real advantage? The images are harder to work with, and require more steps to work with them (at least with what I have to work with). |
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07/11/2005 08:25:11 PM · #30 |
Ok, I just walked over to my neighbors house and took these two pictures as examples. Nothing has been done to either except resize and save for web:
Non-raw mode: 
Raw mode: 
ALL settings were identical except one was shot RAW and one JPG. What am I doing wrong if RAW is supposed to be better?
In the raw one the colors seem flat where the nonraw one they seem vibrant and more there.
EDIT: Oh yeah, well the raw one was converted to jpg but it looks the same as the actual raw version when seen side by side. As in the RAW version has the same flat looking colors.
Message edited by author 2005-07-11 20:29:38. |
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07/11/2005 08:37:13 PM · #31 |
Originally posted by Alienyst:
I shoot in jpeg and my images look better, cripser, more colorful, at least to me. So what is the real advantage? The images are harder to work with, and require more steps to work with them (at least with what I have to work with). |
The main advantage for me is that I like to correct the white balance, which is much easier to do in RAW mode than it is in others. The whole catch to RAW though, is that you have to be willing to edit your pictures. The reason that the JPEG version looks better is because, as has been mentioned, JPEGs are processed in-camera. They are saturated, sharpened, have added contrast, white balance corrections, etc. RAW files leave the ultimate in customization to the user - not the camera.
My processed RAWs generally look much better than they would have if I had captured them in JPEG (perhaps I'm leaning too much on digital editing? who knows..), because I can control white balance and a variety of other features all at once.
There are good photographers who still prefer JPEG - but I will surely never turn back to JPEG.
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07/11/2005 08:40:30 PM · #32 |
With jpeg whatever settings you have set (saturation, contrast etc.) are applied to the image in camera. The image is compressed to 8 bits/channel. If you don't plan on doing any or just very little post processing then you're probably fine.
With RAW the in camera settings really mean nothing as it's the RAW data being recorded, 12 bits/channel. The extra bits give a lot of leway in post processing before any problems start appearing in the image.
Let me explain that...
When you first open an image the histogram shows as solid, all colours covered. When you start making adjustments holes start to appear in the histogram. Once the holes get big enough artifacts start to show like posterization. With more bits/channel to start with you have more room for adjustments.
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07/11/2005 08:56:12 PM · #33 |
I guess I need to get either a new computer that will run XP so I can run the Digital Professionl software that comes with the camera, or invest the megabucks to get PS CS so I can edit raw images in that. I have no problem post processing images and like the capabilities it gives me. The techniques are very different than what I used in the darkroom (obviously) but the effects are the same. I just found that the Utility that does run on my computer (the EOS Viewer Utility) is very limited and not very good when it comes to editing the images. So RAW is not really an option until I make one of those two moves.
Thx for the responses. |
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07/11/2005 08:58:05 PM · #34 |
Originally posted by Alienyst:
I guess I need to get either a new computer that will run XP so I can run the Digital Professionl software that comes with the camera, or invest the megabucks to get PS CS so I can edit raw images in that. I have no problem post processing images and like the capabilities it gives me. The techniques are very different than what I used in the darkroom (obviously) but the effects are the same. I just found that the Utility that does run on my computer (the EOS Viewer Utility) is very limited and not very good when it comes to editing the images. So RAW is not really an option until I make one of those two moves.
Thx for the responses. |
//www.pixmantec.com/index2.html
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07/11/2005 09:01:25 PM · #35 |
Originally posted by Alienyst:
I guess I need to get either a new computer that will run XP so I can run the Digital Professionl software that comes with the camera, or invest the megabucks to get PS CS so I can edit raw images in that. I have no problem post processing images and like the capabilities it gives me. The techniques are very different than what I used in the darkroom (obviously) but the effects are the same. I just found that the Utility that does run on my computer (the EOS Viewer Utility) is very limited and not very good when it comes to editing the images. So RAW is not really an option until I make one of those two moves.
Thx for the responses. |
But there is a free alternative: Rawshooter Essentials. It's very good, except it doesn't allow you to crop like Bibble does.
And some lower cost alternatives: Breezebrowser, Bibble, Thumbsplus, to name a few. Also Photoshop Elements 3 will do RAW.
And then there's expensive stuff too ;)
Why not try the free trials of Photoshop, PS Elements, Bibble, etc. and see what you like. |
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07/11/2005 09:06:13 PM · #36 |
The RGB weightings for luminance calculation depend on the colour space involved. The popular (30,59,11) triplet is actually based on NTSC RGB. The values for sRGB and adobeRGB would be (21,72,7) and (30,63,7) respectively. I'm not convinced any of these spaces were selected for in-camera luminance histograms. Regardless, it is certainly green-heavy (and not because Bayer sensors are green heavy). If you're shooting red/blue/purple subjects, the histogram will lie to you with a straight face.
As far as I know, at least with my camera, the clipped highlights indicator (flashing pixels) starts to kick in within 1 stop of actual clipping. A few flashing specular highlights may not be so bad. There's really no way to tell unfortunately.
As someone mentioned earlier, you can't really expose to the right when your scene already has 5-6 stops of dynamic range. You may end up clipping one way or another so the rules for getting it right at the scene still apply. When in doubt, and where practical, bracketing may help, even if it's just +/-1/3 or 1/2 a stop. There are other times when it's impractical to expose to the right as well; a half-stop or more is a big change when shooting action or in low light situations.
In a some thread somewhere I posted example shots of a low light scene using different shooting parameters, including a comparison of a normal exposure and a to-the-right exposure.
If you really want to know if it's of any practical value to you, take some of your typical shots both ways (normal and to-the-right exposures) and compare on screen (and/or in print). The theory is real, but coping with the dynamic requirements of TTR exposure is just one more thing to worry about when trying to get the perfect shot; it might not be worth it for you. Digital cameras still seem to be designed to expose as we would with film (not a bad thing of course), but it would be nice if we had the ability to expose for highlight control.
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07/11/2005 09:13:38 PM · #37 |
> Alienyst:
RAW offers more data, more pixels than jpg. Having more information available also provides you with a greater range of potential (edit-) adjustments in PS.
The RAW Converter (a PS plugin), allows you to manipulate the WB, i.e. to set a warmer or cooler colour temperature. It enables you to prepare an image for editing, and, if you take advantage of it, provides you -potentially and prior to applying your usual editing tools- with an image that can be drastically different from the jpg straight out of the cam.
If, however, you do not employ the RAW Converter tools for what they're designed to do, you might indeed end up with an image which, at least, appears quite similar to an unsharpened, unsaturated jpg out of the box. While, as a (so-called) 16-BIT RAW file, it still carries more information than a jpg, some of its data (WB, for instance) can only be manipulated by the converter. It is for all intent and purposes lost to you and the world, if you don't use it when you can.
The second you change a RAW file to 8-BIT mode (which you need to do eventually in order access certain tools and filters), you throw away even more information (pixels).
The beauty of the RAW Conversion is in its tools which enable you to see/render an incredible range of possible edits without throwing away any pixels. This not only takes full advantage of the dynamic range of your camera, but also can also provide you files big enough to print out decently (discernible image quality) at large sizes.
Message edited by author 2005-07-11 21:16:31.
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07/11/2005 09:16:03 PM · #38 |
Originally posted by Sonda:
"Within the first F/Stop, which contains the Brightest Tones 2048 levels available
Within the second F/Stop, which contains Bright Tones 1024 levels available
Within the third F/Stop, which contains the Mid-Tones 512 levels available
Within the fourth F/Stop, which contains Dark Tones 256 levels available
Within the fifth F/Stop, which contains the Darkest Tones 128 levels available
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Wait a minute.... this just hocus-pocus with binary numbers. And since most people don't understand binary, most won't even realize what is going on.
The first difficulty is that if you have 12 "bits" of data (values ranging from 0 to 4095) then you're going to have a hard time splitting those 12 bits into "5 convenient buckets" called f-stops. (no, you can't have a fractional bit ... so if you have 5 buckets, three of them will have 2 bits each, and 2 of them will have 3 bits)
It might have been easier to say that you had 6 f/stops of exposure and then divided the 12 bits into 2 bits per f/stop. But ... do you see where I'm going? If each f/stop has only 2 bits, then each f/stop has exactly 4 values (00, 01, 10, and 11).
So what if you have a bucket (I mean, f/stop) that has 3 bits? Well, then you have a grand total of 8 values! Let's see: 000, 001, 010, 011, 100, 101, 110, 111. That's it. Eight values.
Now wait a minute you say... how can the top f/stop have 2048 values??? Surely the author of the article you read wasn't lying to you. Okay ... not lying. He just showed that he doesn't understand the difference between "NUMBER of values" and the "RANGE of those values".
Let's take a look at a 12-bit value. Here it is: 1111-1111-1111. Count 'em, 12 bits. Want to see it again? 4095. Same number. All I did was convert it to decimal.
I purposely represented the 12-bit value in groups of 4 to help illustrate my point. Let's pick 4 bits. How many VALUES do we get out of 4 bits? The answer is 16. Here we go: 0000, 0001, 0010, 0011, 0100, 0101, 0110, 0111, 1000, 1001, 1010, 1011, 1100, 1101, 1110, 1111.
What are the RANGE of those 16 values? Well, if we use the LAST 4 bits, (0000-0000-0000 to 0000-0000-1111) then the RANGE of values is simply 0 thru 15.
What if I use the FIRST set of 4 bits (i.e. 0000-0000-0000 to 1111-0000-0000) then the RANGE of values is from 0 to 3840.
WOW, you're thinking... I'm going to always use the top 4 bits instead of the bottom 4 bits. I get more numbers, right? Well no. You don't. You still only get 16 "values". It's just that there are a lot of holes (when represented in DECIMAL form) in between those values.
Don't believe me? The first one (0000-0000-0000) is obviously 0. The next 0001-0000-0000 is 256, then 512, then 768, then 1024 and so on.
So while it's true that the very left-most bit of a 12-digit number has a decimal representation of 2048 (i.e. 1000-0000-0000 equals 2048) even that one bit still only has 2 values (0 and 2048 - it's either on or off there are no values in between, you can't have a fractional bit).
So what's my point?
My point is... sure you can claim that "Within the first F/Stop, which contains the Brightest Tones 2048 levels available". But you're over simplying. You're stating the RANGE of numbers, not the NUMBER of values.
The first f/stop doesn't have any more "values" in it than the last f/stop. All that is different is that you're playing on the top or bottom end of the binary value.
Don't let the "range" of values get confused with the "number" of values.
In my opinion... you're as likely to blow the highlights (once all the bits are 1's you can't turn them back into 0's) as you are to lose the shadows (after all the bits are 0's you can't turn them back into 1's).
Get a good exposure and save both ends. :-)
Yo, Laurie... how are the math skills coming???
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07/11/2005 09:19:10 PM · #39 |
By the way, don't let any of what I just said confuse the issue of shooting raw versus jpeg.
I would much rather play with 12 bits than 8 bits ... any day.
Sure, it's a little more work on the back end. I have to decide when to collapse my 12-bits down to 8-bits for the purposes of displaying on a monitor or printing on a page.
But the longer I can stay in 12-bit mode, the longer I can keep hold of important pieces of data.
And don't confuse your software's 16-bit mode and 12-bit mode. They are the same. Your software is simply using 16 bits (a native number of bits on the cpu) to store your 12 bit data.
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07/11/2005 09:44:25 PM · #40 |
zeuszen/nshaprio:
Thanks for the response and the suggestions/info.
I will look for the software tomorrow. PS CS - I have the trial version and I did install it but created conflicts with EVERY other piece of software I have for image handling except NeatImage. I found that unacceptable so I uninstalled it. Elements 3 - I had Elements 2 installed and it never seemd to work right. It came with my camera, I installed it, and it crashed every time I loaded an image and tried to do anything with it so I uninstalled that.
What I do have installed that works is PhotoImpact 10, NeatImage, and a host of filters/plug-ins from Flaming Pear, Drosnan (sp?) and optikVerve (sp?). BUT, PI10 does not do RAW files or at least I have not found a plug-in that will do Canons RAW files in PI10. If I could find one of those that would be the gnats a...never mind. It would be good.
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07/11/2005 09:47:20 PM · #41 |
And as in the other thread of my learning tonight, I would like to thank all who responded, offered help/suggestions/technical info. I learned a lot and don't think anyplace else would have afforded me such knowledge in such a short time.
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07/11/2005 09:47:46 PM · #42 |
If cost is an issue (and even if it isn't), I highly recommend the software the kyebosh and nshapiro recommended. Very versatile and has good results with RAW images.
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07/11/2005 09:53:14 PM · #43 |
In JPEG, the camera uses its settings for WB, exposure, saturation, etc.
In RAW you can look at the same image with 100 different white balances, exposure from one end of the spectrum to the other, saturate and desaturate at will changing hues while you do it, plus a myriad of other neat gizmos. All WITHOUT changing the original file. This is the magic of RAW.
JPEG is prettier out of camera because everything is done. Raw gives you so much latitude to make your own decisions that its hard not to enjoy it.
A comparison? How about a McDonald's hamburger compared to one off your grill? Or an automatic tranny sports car compared to a stick shift? Or store bought brownies compared to Mom's homemade? Starbucks coffee Vs. 7-11? You get the idea... :)
d who swears by RSE
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07/11/2005 10:05:58 PM · #44 |
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.
Message edited by author 2005-07-11 22:10:08. |
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07/11/2005 10:16:53 PM · #45 |
Originally posted by dahkota:
In JPEG, the camera uses its settings for WB, exposure, saturation, etc.
In RAW you can look at the same image with 100 different white balances, exposure from one end of the spectrum to the other, saturate and desaturate at will changing hues while you do it, plus a myriad of other neat gizmos. All WITHOUT changing the original file. This is the magic of RAW.
JPEG is prettier out of camera because everything is done. Raw gives you so much latitude to make your own decisions that its hard not to enjoy it.
A comparison? How about a McDonald's hamburger compared to one off your grill? Or an automatic tranny sports car compared to a stick shift? Or store bought brownies compared to Mom's homemade? Starbucks coffee Vs. 7-11? You get the idea... :)
d who swears by RSE |
ok ok you are overdoing it. RAW is better if you are looking to work on your image. You have more flexebility and ways to fix in camera settings. JPG is better if you can get all your in camera settings just right. It all depends on how, where and what you shot for. That's all.
If you have a PERFECT jpeg it is all you will every need.
Nick
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07/11/2005 10:23:48 PM · #46 |
| Even further depressing...Bibble won't work either. I guess it is time for a new computer. But if I go with an XP system I give up the interweb. What a dilema. If I stay with a 98 system I can use the interweb but not do anything with RAW images. |
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07/11/2005 10:23:53 PM · #47 |
Originally posted by Nikolai1024:
ok ok you are overdoing it. RAW is better if you are looking to work on your image. You have more flexebility and ways to fix in camera settings. JPG is better if you can get all your in camera settings just right. It all depends on how, where and what you shot for. That's all.
If you have a PERFECT jpeg it is all you will every need.
Nick |
I'm not that good. And what my camera sees and what I see are completely different animals. Well, okay, we see the same animals but they look really different. :)
d |
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07/11/2005 10:30:48 PM · #48 |
@dwterry:
While your treatise on binary numbers is interesting, you draw a conclusion that is not supportable. You state that "you cannot have a fractional bit." Incorrect. 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. These levels may be assigned in any way that is convenient, including assigning them to different "stops." Since CCD and CMOS sensors are linear devices, the mapping would look similar to that originally posted.
In short, the number of electrons that can be held at each sensing location determines, to a large degree, the dynamic range available. The bit depth of the resulting digitized file determines how finely those levels are divided. The RAW file is a linear representation of the charge accumulated at each site. As such, the assertion that about half the levels available are used for the brightest 1 stop is essentially correct.
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07/11/2005 10:44:22 PM · #49 |
seriously...don't expect to shoot in RAW and get some super images ready for web-view.
There is probably no difference in IMAGE QUALITY when viewed in web size, no difference when viewed in a 4x6, and little if any difference even viewed at an 8x10.
If you learn to shoot right the first time, and make your settings correct, there is no need for RAW for the basic photographer.
It complicates things, and adds unecessary steps to the workflow.
Read this, then form your own opinion on RAW.
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//www.kenrockwell.com/tech/raw.htm
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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.
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07/11/2005 11:03:47 PM · #50 |
| in the same regard, when shooting motion picture film you can get more leniancy by shooting it a little overexposed and bringing it down during the telecine... |
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