Which ISO for rebel for best dynamic range?

[DocFrankenstein]

I keep hearing pros using ISO 200 on 1 series cameras, because the dynamic range is better there.

I was wondering if ISO 200 would be the way to go... since the noise is still minimal if noticeable at all. :confused:

[poke]

If someone knows the answer to that... hopefully they will know for a 20D as well :)

[PhotosGuy]

I don't know if there is an answer for that either, but if you shoot RAW so you can have several "different" exposures to play with, there are several ways in PS to increase dynamic range after the shot is taken. Come to think of it, there's at least one way besides levels/curves to do it without RAW, too.

[snibbetsj]

I think, by definition, the highest ISO will yield the widest dynamic range. That said, when you run it through a noise reduction program, you will necessarily shorten the dynamic range. Perhaps pick an ISO where the noise is acceptable and using that one, say 200 or 400. Either seems fine on my 20D. (Although I always shoot at lowest possible ISO)

[cmM]

But does you dynamic range increase by a big enough amount to even notice (when changing ISO) ?
The difference is probably small...

[Steve Parr]

As a general rule of thumb, I'll generally shoot at the lowest ISO possible to still get the shot. This may or may not be the ideal way to go, but it works out okay for me.

Then again, I'm still learning about all of this. Hell, I've never even taken a shot in RAW mode...

Steve

[snibbetsj]

But does you dynamic range increase by a big enough amount to even notice (when changing ISO) ?
The difference is probably small...

To me it's unnoticeable (excepting the case where going to 1600 or 3200 obviously). I will change ISO to get the shutter speed I need anywhere from 100 to 800 and I certainly can't tell an increase (got to be there though). Probably have to put a print up against negative film or 1DsII output to really tell.

[PhotosGuy]

Probably the best way to preserve dynamic range would be to shoot RAW & process to 16 bit in the first place, no?

[kb244]

I'd likely shoot ISO 100 , Bump the exposure up a little bit ( ie: Expose to the Right on the histogram ), shoot raw ( its 12 bits not 16 by the way, tho 4096 shades per channel still better than 255 ), there's an article somewhere on the web by luminous landscape about maximizing Signal-to-noise ratio to get the highest dynamic range.

EDIT : Here it is, http://www.luminous-landscape.com/tutorials/expose-right.shtml

[PhotosGuy]

( its 12 bits not 16 by the way True, but without looking, I think you GET 12 bits when you PROCESS 16 bits. No biggie, I suppose. Still more dynamic range.
there's an article somewhere on the web by luminous landscape about maximizing Signal-to-noise ratio to get the highest dynamic range. Try: Expose (to the) Right (http://www.luminous-landscape.com/tutorials/expose-right.shtml)

[pradeep1]

I tend to shoot at the lowest ISO in RAW+JPG and Expose to the Right. That seems to keep the maximum range.

[griff2]

Theoretically, at least, increasing ISO degrades signal-to-noise ratio, purely because the higher ISO is achieved via amplification: as you increase the gain you increase the noise. So, the best ISO should be the lowest..

[robertwgross]

I think you GET 12 bits when you PROCESS 16 bits.

Getting 12 bits out of a 16-bit format is still a lot better than trying to get it out of an 8-bit format.

---Bob Gross---

[drisley]

Probably the best way to preserve dynamic range would be to shoot RAW & process to 16 bit in the first place, no?
Absolutely!
I only shoot Raw, and especially with the 20D, I've been able to save a few overexposed images that would have been lost as a jpg.
Btw, I was always a big "expose to the right" shooter with the 300D.
But, I find I no longer have to do this with the 20D since the noise levels are low, and the dynamic range is greater. :)

[snibbetsj]

Obviously shooting raw and processing in 16-bit tifs is the best way to preserve the dynamic range of the original shot, however, the original question was whether or not ISO 200 has a larger dynamic range than ISO 100. I believe the answer is: yes it does.

[tim]

Even better, shoot on a tripod, one shot exposed for the shadows, one shot exposed for the highlights, and blend the two in photoshop for an amazing dynamic range. Processing RAW at different EC levels lets you do this, but you end up with a bit more noise in your shadows.

Blending exposures can be tricky, and there are at least two way to do it, neither of which i'm really happy with.

[drisley]

That is interesting. I always thought higher iso=less dynamic range.
Since the noise level of ISO100 and ISO200 on the 20D are the same, it almost makes sense to use ISO200 as much as possible then.

[gasrocks]

I believe you are a Raw user or not - depending on your situation. If I am close to home, close to my computer and WB really matters - RAW + a jpg (you need a jpg only to find the correct Raw file easily.) I challange my students to find any difference with the best JPG and RAW - most cannot take advantage of RAW technology, therefore, a waste of space. Is RAW only another crutch for saving pix that you didn't do quite right?

[tim]

RAW is most helpful in difficult lighting situations, or when you want maximum control over your images. If you take JPG, then edit them in Photoshop, then save them again, you've gone through two jpeg compression cycles, reducing quality. Also, if you want to tweak levels or colors, there's just more information saved in RAW, so you do end up with better image quality than JPG.

I can browse RAW (CRW & CR2) using the PS CS browser or using a Windows shell extension, so I don't need a JPG for browsing.

[PhotosGuy]

Is RAW only another crutch for saving pix that you didn't do quite right? :D:D It sure helps when I really screw up! See:
Why I love RAW - '53 Ford Sunliner
http://photography-on-the.net/forum/showthread.php?t=43761&highlight=sunliner

I think the that the most important difference is "Probably the best way to preserve dynamic range would be to shoot RAW & process to 16 bit in the first place, no?" as I said before. (300D = 12 bits.)

...most cannot take advantage of RAW technology, therefore, a waste of space. Maybe now, but when they know more, they can pull the old "negative out of the box" & reprocess it with whatever new RAW extraction tech that exists at the time.

[drisley]

I believe you are a Raw user or not - depending on your situation. If I am close to home, close to my computer and WB really matters - RAW + a jpg (you need a jpg only to find the correct Raw file easily.) I challange my students to find any difference with the best JPG and RAW - most cannot take advantage of RAW technology, therefore, a waste of space. Is RAW only another crutch for saving pix that you didn't do quite right?
I am TOTALLY a Raw user.
I only shoot Raw, and I can get much better results with a Raw workflow than I can with JPG. This is especially true in extreme lighting conditions.
If I would have shot my last bodybuiling pictures in JPG, they would have been a mess do to limited dynamic range, and difficult white balance.

[drisley]

Here is a great read imho...

Sermon From A Raw Convert (http://194.100.88.243/petteri/pont/How_to/o_RAW_workflow/_RAW_workflow.html)

[ron chappel]

That is interesting. I always thought higher iso=less dynamic range.
Since the noise level of ISO100 and ISO200 on the 20D are the same, it almost makes sense to use ISO200 as much as possible then.


Most of us think that ,but it's based on the assumption that the lowest ISO setting is the 'native' setting and all others are amplified from that which may not nessesarily be true.

The sensor could work normally (without amplification) at ISO200 which would then mean the signal at ISO100 needs to be CUT.

'course i'm just guessing here :)

[tim]

I read somewhere the Nikon D70 doesn't have ISO 100 because ISO 200 is just as good. I'm not sure of that though.

[ron chappel]

I'm glad they still have ISO100 on the canons,i need it occasionally is bright light when i don't want too much DOF

[DocFrankenstein]

By definition, 12 bit bodies have a theoretical dynamic range of 3.6

8 bit jpeg has 2.4

http://www.photo.net/learn/drange/

RAW helps in that regard. But then at higher ISO one would expect to have less dynamic range due to increased noise affecting the darkest areas...

So why do pros shoot ISO 200 again? Make no sense to me!

[ron chappel]

Doc you shouldn't be using that logarithmic measuring method - it's very confusing to those that are used to measuring light in stops! :eek: :eek: so means nothing to normal people

[fatrat]

I'd likely shoot ISO 100 , Bump the exposure up a little bit ( ie: Expose to the Right on the histogram ), shoot raw ( its 12 bits not 16 by the way, tho 4096 shades per channel still better than 255 ), there's an article somewhere on the web by luminous landscape about maximizing Signal-to-noise ratio to get the highest dynamic range.

EDIT : Here it is, http://www.luminous-landscape.com/tutorials/expose-right.shtml

It 12 bit eh? then whats the deal when i open a RAW CR2 from my 20D it says in Photoshop it the Metadata
Bit Per Sample 16,16,16
Which = 48Bit, 16 Per channel?
Is Photoshop lying?

Also if you can tell the differance in noise betwwen ISo 100 and ISO 200, well you have a mean set of eyes

[Jon]

It 12 bit eh? then whats the deal when i open a RAW CR2 from my 20D it says in Photoshop it the Metadata
Bit Per Sample 16,16,16
Which = 48Bit, 16 Per channel?
Is Photoshop lying?

Also if you can tell the differance in noise betwwen ISo 100 and ISO 200, well you have a mean set of eyes

The converted image has room for 16-bit data. But the sensor only recorded 12-bit. If you count the numbers of colours present, you'll find it's only got 2^36 (max., or 68 billion) colours. If you do any kind of editing, some of those "unused" colours may be filled in through interpolation, but the original picture only recorded data to support the "basic" 68B.

[DocFrankenstein]

Doc you shouldn't be using that logarithmic measuring method - it's very confusing to those that are used to measuring light in stops! :eek: :eek: so means nothing to normal people
ok, so how many stops is the DR of the Drebel? :D