Auto ISO...do you use it?

VaughnA · 06-04-2010, 06:11 AM

With my K20D I usually just used TAV and 'chose' ISO on the fly depending on the conditions. I've since switched to a K-x (yes, and I love it). With it's excellent performance at higher ISO's I usually leave it in auto 100-1600 and let it rip in Av. It usually chooses what I would for those conditions. Depending on conditions I might up it to 32 or even 6400 in auto. I basically set the high end as high as I'm comfortable and let it choose. I've always got the option to drop it down if I don't like what it is doing.

Bottom line, let it choose and if I don't like it then change it. Since it chooses lowest ISO most of the time I rarely have to change it. Less muss & fuss.

graphicgr8s · 06-04-2010, 06:21 AM

Most of my shooting is manual mode. After I am done with my shoot I put the camera in green but never let the camera change ISO. I put there so that if a shot comes by and I dont have time to fiddle I can at least get a useable shot which os better than no shot. But never let it change ISO.

Edvinas · 06-04-2010, 06:35 AM

Originally posted by graphicgr8s

Most of my shooting is manual mode. After I am done with my shoot I put the camera in green but never let the camera change ISO. I put there so that if a shot comes by and I dont have time to fiddle I can at least get a useable shot which os better than no shot. But never let it change ISO.

Let me ask you why are you doing this? Having Auto ISO on you just increase your chances to get useable shot. It won't ruin it.

graphicgr8s · 06-04-2010, 07:53 AM

Originally posted by Edvinas

Let me ask you why are you doing this? Having Auto ISO on you just increase your chances to get useable shot. It won't ruin it.

I personally prefer to choose the ISO. I just haven't found the camera to choose what I would. So I make it mandatory. All that said, I've never missed a shot because of ISO.

TaoMaas · 06-04-2010, 08:05 AM

No, I don't use it, but I probably ought to employ it when the situation permits. When I first started in digital photography, I let the camera do a lot of the thinking. Now, I prefer to have a firm set of parameters and work within those guidelines. Feels more like film to me.

Marc Sabatella · 06-04-2010, 08:25 AM

I should add a few things:

- While *I* don't use auto ISO, I'm not saying no one else should

- Although I set ISO myself, I don't tend to muck with it often. 100 outdoors, 1600 indoors. Only rarely do I choose anything in between - maybe 200 or 400 shooting telephoto outdoors in less than bright sunlight, maybe 800 indoors during the day. Then I tend to just let it ride for the whole shoot.

- For me, there is a hard and fast line between fully manual mode, in which I and only I decide what the exposure will be and once se it stays set, and *all* other modes, in which the camera decides the exposure and potentially varies it from shot to shot. If I were OK with being on the latter side of the line where I let the camera choose how light/dark to make the picture, I'd be fine with auto ISO. I don't distrust the camera to choose ISO any more than I distrust it to choose any other aspect of exposure. In fact, while I'm thinking of it, I just now set P mode on my camera set to use auto ISO. That way if I ever do hit a situation where I feel like letting the camera take control (wildly varying light, handing the camera to someone else for a while when I can't set it up for them on each shot, etc), there's nothing to think about.

mz-3 · 06-04-2010, 08:58 AM

TAV mode is good if the auto ISO range is between 100 and 400.

stevebrot · 06-04-2010, 09:17 AM

I use Auto ISO in P mode when shooting snapshots where there may be a mix of indoors and outdoors and flash is not a good idea. TAv mode was one of the selling points of the camera, but I have to admit to only using it a few times in the last 3 years. When I've needed it, I was glad it was available.

Steve

alexeyga · 06-04-2010, 09:29 AM

Some of the replies are so funny... people yapping with intelligent faces about iso and stuff without having a slightest clue about how camera's metering system works...

That being said, I don't know about Sony and current Canon models, but Pentax seems to have the only WORKING auto-iso on the market... And it's realized very well in K7 with the possibility to adjust the target zone (slow-normal-fast)... What's really great about the way Pentax did it, AUTO-ISO is a function of the current FL which makes all the difference... as on the N.... side of the grass, you have to input the FL and minumum shutter speed manually... thus, rendering this future virtually useless unless you shoot primes or you're in the M-mode... even then, every time you change a lens you need to go digging menus...

Very useful feature b.t.w. when used properly...

graphicgr8s · 06-04-2010, 10:14 AM

Originally posted by alexeyga

Some of the replies are so funny... people yapping with intelligent faces about iso and stuff without having a slightest clue about how camera's metering system works...

That being said, I don't know about Sony and current Canon models, but Pentax seems to have the only WORKING auto-iso on the market... And it's realized very well in K7 with the possibility to adjust the target zone (slow-normal-fast)... What's really great about the way Pentax did it, AUTO-ISO is a function of the current FL which makes all the difference... as on the N.... side of the grass, you have to input the FL and minumum shutter speed manually... thus, rendering this future virtually useless unless you shoot primes or you're in the M-mode... even then, every time you change a lens you need to go digging menus...

Very useful feature b.t.w. when used properly...

So why don't you clue us in Professor? How does it determine what exposure to use? Which ISO? Please explain. We are waiting with bated breath.

alexeyga · 06-04-2010, 10:23 AM

Originally posted by graphicgr8s

So why don't you clue us in Professor? How does it determine what exposure to use? Which ISO? Please explain. We are waiting with bated breath.

Buddy, i'm not here to clue anybody on anything... just gave my opinion and it wasn't the point of my post anyways... what's up? have you felt insulted of something?

gkreth · 06-04-2010, 10:45 AM

Originally posted by alexeyga

Buddy, i'm not here to clue anybody on anything... just gave my opinion and it wasn't the point of my post anyways... what's up? have you felt insulted of something?

Well, you DID say:

Originally posted by alexeyga

Some of the replies are so funny... people yapping with intelligent faces about iso and stuff without having a slightest clue about how camera's metering system works...

I could see how someone might feel insulted by that....

Greg

Ira · 06-04-2010, 11:01 AM

Originally posted by alexeyga

Some of the replies are so funny... people yapping with intelligent faces about iso and stuff without having a slightest clue about how camera's metering system works...

I would say that the above can pretty much be classified as obnoxious.

Bart · 06-04-2010, 11:09 AM

I always use Auto-ISO from 100 - 640 on K10D, mostly on Av.
You see the result in the viewfinder.
If you don't like the outcome, simply change either of the appropriate parameters.
One push of the green button brings you back to the automated suggestion.
Easy.

gkreth · 06-04-2010, 11:19 AM

Originally posted by Reportage

i find that its a tad erratic even in the best of times for my k20d. Can have extreme differences in iso for repeated shots of the same subject.

I use auto-ISO all the time on my K-x; never used it on the K10D - well, except when I used TAv, which was sometimes, but not often. (I found the four stops of 100 to 1600 too limiting, and had to keep metering all the time, anyway...)

Example of when I use it on the K-x: Shooting soccer, outdoors, using the DAL 55-300 (f/4 to f5.8). because I'm usually in the 150mm to 300mm FL, wide open usually means f/5 to f/5.8. Because it's moving action, I set the shutter speed to 1/400, sometimes 1/500 or even 1/640. I set the Auto ISO to go up to ISO 1600, maybe ISO 3200.

By doing this, the f/stop stays in the f/8 to f/11 range, which works better for me than being wide open at f/5.8: A little more DOF, a little stopped down to the sweet spot.

Now, I wouldn't do this with the K10D, because, even outdoors in good light, ISO 1600 was not kind on the K10D's CCD sensor. But the K-x, with it's great CMOS sensor and wonderful in-camera JPEG engine, I have zero fear shooting at ISO 1600, ISO 3200, even ISO 6400.

Another example: Shooting indoors w/o flash, I use Auto ISO up to 128K, often on P mode? Why? Because I use zooms, and not fixed-aperture zooms. So at 50mm or 60mm I could be at f/4, but at 150mm or 200mm I could be at f/5.6 In this case i don't like shooting in Av mode, because I feel like I need to keep changing the aperture as the FL changes; either that, or set the aperture stopped down for the longest FL, e.g., set it at f/8. Doing that indoors often causes the shutter speed to slow down too much for the focal length.

On the K10D, I often would shoot, chimp, change the ISO, and shoot again. On the K-x, I set the Auto ISO shoot, chimp, and am usually very happy with the results. I rarely have to re-shoot a scene because the shutter slowed down too much, and I got blur.

I have not confirmed this, or scientifically tested it, but from casual observance, in P mode with DA lenses the K-x seems to modify many parameters based on the lens being used and the FL. For instance, it knows when the DAL 55-300 is shooting at 55mm and when it's at 300mm, and it appears to modify all three parameters to keep a happy medium:

At 55mm, the K-x knows that f/5.6 is "stopped down one", and also that a shutter speed of 1/80 would generally suffice for camera shake. So it stays around there, and adjusts the ISO as needed. When the ISO is maxed at 6400 (or 128K, if i set it there), and 1/80 + f/5.6 still meters too dark, the K-x first opens to f/4, and then if it's still too dark, the K-x drops the shutter speed.

Again, this is not scientifically tested, but it seems to be what i have observed. And it's exactly how I would do it manually: bump up the ISO until you get to your "comfortable" max, then open the aperture, then drop the shutter speed. (Obviously Av mode would freeze the f/stop and go right to dropping the shutter speed. And Tv would freeze the shutter speed value, and open the f/stop.)

For the same lens, but shooting at 300mm in P mode, again, the K-x seems to intuitively do what I would do manually: It tries to keep the shutter around 1/200 or 1/250, which I assume would be the 1/FL rule, but adding a stop for SR. It also tries to keep the f/stop at f/8, i./e., stopped down one from wide open.

Set like this, the ISO increases as needed until it hits the max, then the f/stop opens more, and last, the shutter speed drops.

I will try to do some controlled tests, to see if I can nail this down and confirm it. But again, it seems an intuitive way to do P mode - or, at least, that's how I would do it manually.

Sorry for the long post. I guess I had more to say than I first thought when i started writing this....

Greg

06-04-2010, 10:45 AM	#42
gkreth Forum Member Join Date: Jul 2009 Location: Austin, TX Posts: 68	Well, you did say... Originally posted by alexeyga Buddy, i'm not here to clue anybody on anything... just gave my opinion and it wasn't the point of my post anyways... what's up? have you felt insulted of something? Well, you DID say: Originally posted by alexeyga Some of the replies are so funny... people yapping with intelligent faces about iso and stuff without having a slightest clue about how camera's metering system works... I could see how someone might feel insulted by that.... Greg

06-04-2010, 11:19 AM	#45
gkreth Forum Member Join Date: Jul 2009 Location: Austin, TX Posts: 68	I use it all the time on the K-x Originally posted by Reportage i find that its a tad erratic even in the best of times for my k20d. Can have extreme differences in iso for repeated shots of the same subject. I use auto-ISO all the time on my K-x; never used it on the K10D - well, except when I used TAv, which was sometimes, but not often. (I found the four stops of 100 to 1600 too limiting, and had to keep metering all the time, anyway...) Example of when I use it on the K-x: Shooting soccer, outdoors, using the DAL 55-300 (f/4 to f5.8). because I'm usually in the 150mm to 300mm FL, wide open usually means f/5 to f/5.8. Because it's moving action, I set the shutter speed to 1/400, sometimes 1/500 or even 1/640. I set the Auto ISO to go up to ISO 1600, maybe ISO 3200. By doing this, the f/stop stays in the f/8 to f/11 range, which works better for me than being wide open at f/5.8: A little more DOF, a little stopped down to the sweet spot. Now, I wouldn't do this with the K10D, because, even outdoors in good light, ISO 1600 was not kind on the K10D's CCD sensor. But the K-x, with it's great CMOS sensor and wonderful in-camera JPEG engine, I have zero fear shooting at ISO 1600, ISO 3200, even ISO 6400. Another example: Shooting indoors w/o flash, I use Auto ISO up to 128K, often on P mode? Why? Because I use zooms, and not fixed-aperture zooms. So at 50mm or 60mm I could be at f/4, but at 150mm or 200mm I could be at f/5.6 In this case i don't like shooting in Av mode, because I feel like I need to keep changing the aperture as the FL changes; either that, or set the aperture stopped down for the longest FL, e.g., set it at f/8. Doing that indoors often causes the shutter speed to slow down too much for the focal length. On the K10D, I often would shoot, chimp, change the ISO, and shoot again. On the K-x, I set the Auto ISO shoot, chimp, and am usually very happy with the results. I rarely have to re-shoot a scene because the shutter slowed down too much, and I got blur. I have not confirmed this, or scientifically tested it, but from casual observance, in P mode with DA lenses the K-x seems to modify many parameters based on the lens being used and the FL. For instance, it knows when the DAL 55-300 is shooting at 55mm and when it's at 300mm, and it appears to modify all three parameters to keep a happy medium: At 55mm, the K-x knows that f/5.6 is "stopped down one", and also that a shutter speed of 1/80 would generally suffice for camera shake. So it stays around there, and adjusts the ISO as needed. When the ISO is maxed at 6400 (or 128K, if i set it there), and 1/80 + f/5.6 still meters too dark, the K-x first opens to f/4, and then if it's still too dark, the K-x drops the shutter speed. Again, this is not scientifically tested, but it seems to be what i have observed. And it's exactly how I would do it manually: bump up the ISO until you get to your "comfortable" max, then open the aperture, then drop the shutter speed. (Obviously Av mode would freeze the f/stop and go right to dropping the shutter speed. And Tv would freeze the shutter speed value, and open the f/stop.) For the same lens, but shooting at 300mm in P mode, again, the K-x seems to intuitively do what I would do manually: It tries to keep the shutter around 1/200 or 1/250, which I assume would be the 1/FL rule, but adding a stop for SR. It also tries to keep the f/stop at f/8, i./e., stopped down one from wide open. Set like this, the ISO increases as needed until it hits the max, then the f/stop opens more, and last, the shutter speed drops. I will try to do some controlled tests, to see if I can nail this down and confirm it. But again, it seems an intuitive way to do P mode - or, at least, that's how I would do it manually. Sorry for the long post. I guess I had more to say than I first thought when i started writing this.... Greg

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06-04-2010, 06:11 AM	#31
VaughnA Banned Join Date: Feb 2009 Location: Virginia Photos: Gallery \| Albums Posts: 1,363	With my K20D I usually just used TAV and 'chose' ISO on the fly depending on the conditions. I've since switched to a K-x (yes, and I love it). With it's excellent performance at higher ISO's I usually leave it in auto 100-1600 and let it rip in Av. It usually chooses what I would for those conditions. Depending on conditions I might up it to 32 or even 6400 in auto. I basically set the high end as high as I'm comfortable and let it choose. I've always got the option to drop it down if I don't like what it is doing. Bottom line, let it choose and if I don't like it then change it. Since it chooses lowest ISO most of the time I rarely have to change it. Less muss & fuss.

06-04-2010, 06:21 AM	#32
graphicgr8s Guest	Most of my shooting is manual mode. After I am done with my shoot I put the camera in green but never let the camera change ISO. I put there so that if a shot comes by and I dont have time to fiddle I can at least get a useable shot which os better than no shot. But never let it change ISO.

06-04-2010, 06:35 AM	#33
Edvinas Veteran Member Join Date: Sep 2006 Location: Kaunas Posts: 1,458	Originally posted by graphicgr8s Most of my shooting is manual mode. After I am done with my shoot I put the camera in green but never let the camera change ISO. I put there so that if a shot comes by and I dont have time to fiddle I can at least get a useable shot which os better than no shot. But never let it change ISO. Let me ask you why are you doing this? Having Auto ISO on you just increase your chances to get useable shot. It won't ruin it.

06-04-2010, 07:53 AM	#34
graphicgr8s Guest	Originally posted by Edvinas Let me ask you why are you doing this? Having Auto ISO on you just increase your chances to get useable shot. It won't ruin it. I personally prefer to choose the ISO. I just haven't found the camera to choose what I would. So I make it mandatory. All that said, I've never missed a shot because of ISO.

06-04-2010, 08:05 AM	#35
TaoMaas Pentaxian Join Date: May 2007 Location: Oklahoma City Photos: Gallery \| Albums Posts: 3,574	No, I don't use it, but I probably ought to employ it when the situation permits. When I first started in digital photography, I let the camera do a lot of the thinking. Now, I prefer to have a firm set of parameters and work within those guidelines. Feels more like film to me.

06-04-2010, 08:25 AM	#36
Marc Sabatella Veteran Member Join Date: Sep 2006 Location: Denver, CO Photos: Gallery Posts: 10,685	I should add a few things: - While I don't use auto ISO, I'm not saying no one else should - Although I set ISO myself, I don't tend to muck with it often. 100 outdoors, 1600 indoors. Only rarely do I choose anything in between - maybe 200 or 400 shooting telephoto outdoors in less than bright sunlight, maybe 800 indoors during the day. Then I tend to just let it ride for the whole shoot. - For me, there is a hard and fast line between fully manual mode, in which I and only I decide what the exposure will be and once se it stays set, and all other modes, in which the camera decides the exposure and potentially varies it from shot to shot. If I were OK with being on the latter side of the line where I let the camera choose how light/dark to make the picture, I'd be fine with auto ISO. I don't distrust the camera to choose ISO any more than I distrust it to choose any other aspect of exposure. In fact, while I'm thinking of it, I just now set P mode on my camera set to use auto ISO. That way if I ever do hit a situation where I feel like letting the camera take control (wildly varying light, handing the camera to someone else for a while when I can't set it up for them on each shot, etc), there's nothing to think about.

06-04-2010, 08:58 AM	#37
mz-3 Inactive Account Join Date: Mar 2009 Location: Pennsylvania Posts: 152	TAV mode is good if the auto ISO range is between 100 and 400.

06-04-2010, 09:17 AM	#38
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	I use Auto ISO in P mode when shooting snapshots where there may be a mix of indoors and outdoors and flash is not a good idea. TAv mode was one of the selling points of the camera, but I have to admit to only using it a few times in the last 3 years. When I've needed it, I was glad it was available. Steve

06-04-2010, 09:29 AM	#39
alexeyga Veteran Member Join Date: Dec 2008 Location: Montreal, Canada Posts: 838	Some of the replies are so funny... people yapping with intelligent faces about iso and stuff without having a slightest clue about how camera's metering system works... That being said, I don't know about Sony and current Canon models, but Pentax seems to have the only WORKING auto-iso on the market... And it's realized very well in K7 with the possibility to adjust the target zone (slow-normal-fast)... What's really great about the way Pentax did it, AUTO-ISO is a function of the current FL which makes all the difference... as on the N.... side of the grass, you have to input the FL and minumum shutter speed manually... thus, rendering this future virtually useless unless you shoot primes or you're in the M-mode... even then, every time you change a lens you need to go digging menus... Very useful feature b.t.w. when used properly...

06-04-2010, 10:14 AM	#40
graphicgr8s Guest	Originally posted by alexeyga Some of the replies are so funny... people yapping with intelligent faces about iso and stuff without having a slightest clue about how camera's metering system works... That being said, I don't know about Sony and current Canon models, but Pentax seems to have the only WORKING auto-iso on the market... And it's realized very well in K7 with the possibility to adjust the target zone (slow-normal-fast)... What's really great about the way Pentax did it, AUTO-ISO is a function of the current FL which makes all the difference... as on the N.... side of the grass, you have to input the FL and minumum shutter speed manually... thus, rendering this future virtually useless unless you shoot primes or you're in the M-mode... even then, every time you change a lens you need to go digging menus... Very useful feature b.t.w. when used properly... So why don't you clue us in Professor? How does it determine what exposure to use? Which ISO? Please explain. We are waiting with bated breath.

06-04-2010, 10:23 AM	#41
alexeyga Veteran Member Join Date: Dec 2008 Location: Montreal, Canada Posts: 838	Originally posted by graphicgr8s So why don't you clue us in Professor? How does it determine what exposure to use? Which ISO? Please explain. We are waiting with bated breath. Buddy, i'm not here to clue anybody on anything... just gave my opinion and it wasn't the point of my post anyways... what's up? have you felt insulted of something?

06-04-2010, 11:01 AM	#43
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	Originally posted by alexeyga Some of the replies are so funny... people yapping with intelligent faces about iso and stuff without having a slightest clue about how camera's metering system works... I would say that the above can pretty much be classified as obnoxious.

06-04-2010, 11:09 AM	#44
Bart Pentaxian Join Date: May 2007 Location: WW community of Pentax users Photos: Gallery \| Albums Posts: 2,646	I always use Auto-ISO from 100 - 640 on K10D, mostly on Av. You see the result in the viewfinder. If you don't like the outcome, simply change either of the appropriate parameters. One push of the green button brings you back to the automated suggestion. Easy.