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Soft Focus of 7d + Canon 400mm F/5.6L

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Old Monday 14th May 2012, 16:25   #1
vipantonio
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Soft Focus of 7d + Canon 400mm F/5.6L

Hello, I'm newbie here :) My Canon EOS 7D + Canon 400mm f/5.6 L BIF photos are soft.

I have read many threads, including this one, and wonder if you could tell from these pics if this is SS problem, or miss focus, or stupid photographer :) ?

I was shooting using One Center Point, AI-Servo mode, High burst rate, Hand-held, RAW. F/7.1, 1/800 sec, ISO 500, 400mm fixed lens mentioned before. Photo on the left is exported directly from Lightroom 4 RAW file, resized to 800px, no sharpening. Photo on the right is 100% crop while zoomed in lightroom and print-previewed, saved fom within Paint program as JPEG.

One more question: how can I check whether I definitely shot in that mode, check Focus point (CF card is already formatted). Thanks

P.S. I have some Bird In Flight photos which show similar results. Should I attach them?
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Old Monday 14th May 2012, 16:29   #2
lmans66
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Quote:
Originally Posted by vipantonio View Post
Hello, I'm newbie here :) My Canon EOS 7D + Canon 400mm f/5.6 L BIF photos are soft.

I have read many threads, including this one, and wonder if you could tell from these pics if this is SS problem, or miss focus, or stupid photographer :) ?

I was shooting using One Center Point, AI-Servo mode, High burst rate, Hand-held, RAW. F/7.1, 1/800 sec, ISO 500, 400mm fixed lens mentioned before. Photo on the left is exported directly from Lightroom 4 RAW file, resized to 800px, no sharpening. Photo on the right is 100% crop while zoomed in lightroom and print-previewed, saved fom within Paint program as JPEG.

One more question: how can I check whether I definitely shot in that mode, check Focus point (CF card is already formatted). Thanks

P.S. I have some Bird In Flight photos which show similar results. Should I attach them?
Get closer to the bird....just because you have a zoom lens will not mean given light conditions, camera settings etc...that it will overcome distance. A small bird at a distance is just that, a small bird at a distance... jim
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Old Monday 14th May 2012, 17:05   #3
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[quote=vipantonio;2439670]
One more question: how can I check whether I definitely shot in that mode, check Focus point (CF card is already formatted).QUOTE]

You can check all of the shooting parameters in the Metadata window in Lightroom.
To check the focus point you need to use either Zoom Browser or DPP.


Since the grass in front of your bird appears to be in focus I think you may have missed your target in this shot. It is also possible that your lens and camera are front focussing.
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Old Monday 14th May 2012, 18:49   #4
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Originally Posted by lmans66 View Post
Get closer to the bird....just because you have a zoom lens will not mean given light conditions, camera settings etc...that it will overcome distance. A small bird at a distance is just that, a small bird at a distance... jim
Thanks for the answers. How about this photo? 1st Cropped 50%, 2nd - zoomed to 100%. 1/1000 sec, f/6.3, ISO 400, same 400mm lens
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Old Monday 14th May 2012, 19:02   #5
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I have a bird of similar size in the frame shot with my 7D and 100-400 at 400mm, 1/125, f/8, 200 ISO, which would imply similar lighting levels between the shots. Certainly mine appears sharper, despite the much slower shutter speed. One thing that seems very obvious in your shot is the noise. That's certainly not helping when your subject is so small, as the noise is really affecting the tiny details. But really it could be a bit of misfocus, a bit of shake - 1/800 is not that fast for examining a 400mm shot from a 7D at 100% - maybe some atmospheric issues and, God forbid, a filter.

Anyway, here's how my broadly similar shot looks, raw, no edits. I think you will spot the difference in noise very clearly. 500 ISO is not a good choice. It is an underexposure in camera at 400 ISO followed by a 1/3 digital push to bring the brightness up to match a 500 ISO equivalent. I've also included a side by side comparison at 100% for convenience.

So, I think there is room for improvement, but I'm not sure quite what steps you need to take to close the gap, because I don't know, other than noise, what other factors are in play. Filling the frame more would go a long way to improving matters on several fronts.
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Old Monday 14th May 2012, 19:04   #6
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Jim is right, I think you are just too far away from the bird with a 400mm lens!
Do you really think that this particular attached photo is from too far away?
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Old Monday 14th May 2012, 19:04   #7
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To prove whether you have an issue with your camera, Stick a page of text from a magazine or newspaper to an outside wall. Make sure you have decent light and mount the camera to a tripod. Shoot the text (camera must be as close to 90 degrees to the wall as possible) at f8, which is probably the sweet spot of the lens.

Check your results on the computer, if the text is sharp and in focus you don't have an issue with the camera or lens and it is probably your technique..

The key to testing this way is that your tripod must be a good quality one, if its flimsy then the camera will move when the mirror lifts and falls (called 'mirror slap') and you will get a blurry shot.

If you don't have a tripod try resting the camera on something stable to prevent it from moving while performing the test.

If you have a focus limiter switch on the lens, check to make sure its not selected and that you are not exceeding the limit else the shot will never be in focus.

Hope this helps....
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Old Monday 14th May 2012, 19:22   #8
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Originally Posted by vipantonio View Post
Do you really think that this particular attached photo is from too far away?
It may well be usable, but it's not optimum. You are already starting out with a "crop" sensor, relative to full frame, and by only partially filling that little sensor with the subject and, presumably cropping in tighter still, you're not maximising the potential offered by the camera. Take it to extremes - lets say cropping to just 1/9 of the frame - and you will turn your 7D into the equivalent of a 2 megapixel point and shoot in terms of sensor area and pixel count, with a 2,000mm FOV equivalent lens waving about in front of it.
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Old Monday 14th May 2012, 19:25   #9
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Originally Posted by vipantonio View Post
Do you really think that this particular attached photo is from too far away?
No it is not to far away for reasonable web images, at that distance you should be getting pin sharp images with the 400/5.6 and 7D. Here are typical results I get with the 400/5.6 (hand held). I have loads more examples like this. I rarely get a shot that I do not have to crop at least 50%. The Wren shot was taken on the 40D.

Your shutter speed of 1/1000 sec should be fast enough, I am not sure what you are doing wrong.
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Old Monday 14th May 2012, 19:31   #10
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Originally Posted by degsy_safc View Post
To prove whether you have an issue with your camera, Stick a page of text from a magazine or newspaper to an outside wall. Make sure you have decent light and mount the camera to a tripod. Shoot the text (camera must be as close to 90 degrees to the wall as possible) at f8, which is probably the sweet spot of the lens.

Check your results on the computer, if the text is sharp and in focus you don't have an issue with the camera or lens and it is probably your technique..

The key to testing this way is that your tripod must be a good quality one, if its flimsy then the camera will move when the mirror lifts and falls (called 'mirror slap') and you will get a blurry shot.

If you don't have a tripod try resting the camera on something stable to prevent it from moving while performing the test.

If you have a focus limiter switch on the lens, check to make sure its not selected and that you are not exceeding the limit else the shot will never be in focus.

Hope this helps....
I agree with this to a certain extent, but if the shots are still soft it might only reveal something about the autofocus of the lens, or, more specifically, if it is working well with your camera body. If the AF is out, at least with the 7D you should be able to micro focus adjust the lens to your body. I disagree that it should be done at F8, as, everything I have read about the 400 F5.6 suggests that it is very sharp wide open, so there should be no need to stop down.

Before testing the accuracy of the AF, I would test the native sharpness of the lens by performing a manual focus test. Again, do this on a tripod, but use live view (magnified to 5x, or even better 10x) to ensure that accurate focus is possible with your particular samples of lens & body. Using live view means there will be no mirror slap to introduce vibration.

I also disagree that either bird was too far away to get sharp shots. It's more likely down to technique (not holding the lens steady enough for the shutter speed) or in the case of the stork, you seem to have the main point of focus behind the bird. It's easy to blame the gear, but at least by testing the lens as described above you can eliminate that possibility first.

edit; should have added that you should use the 2 second self timer when performing the manual focus sharpness test in live view.

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Old Monday 14th May 2012, 19:45   #11
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I also disagree that either bird was too far away to get sharp shots. It's more likely down to technique (not holding the lens steady enough for the shutter speed) or in the case of the stork, you seem to have the main point of focus behind the bird. It's easy to blame the gear, but at least by testing the lens as described above you can eliminate that possibility first.
I agree with Steve 100% here.
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Old Monday 14th May 2012, 19:54   #12
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Huge thanks for all of you, guys, really appreciate it. Definitely not using any filters here :)

Can I believe in those photos that Micro Adjustment +2 gives significantly better results? (since I have only that kind of scratchy wall against my balcony). Or should I stick to testing the Text in front of a wall (but this gonna be next day, since it is late now here in Lithuania) :)
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Old Monday 14th May 2012, 20:22   #13
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Originally Posted by vipantonio View Post
Huge thanks for all of you, guys, really appreciate it. Definitely not using any filters here :)

Can I believe in those photos that Micro Adjustment +2 gives significantly better results? (since I have only that kind of scratchy wall against my balcony). Or should I stick to testing the Text in front of a wall (but this gonna be next day, since it is late now here in Lithuania) :)
I'll be honest and say I don't see a huge difference between these two, but then the subject matter is such that it is difficult to see if it is really sharp or not, because of the texture of the wall. Also, are these using MF or AF?

Personally I find using a £10 note (or similar) more easy to judge true sharpness. + or -2 isn't that much micro adjustment either, so I wouldn't expect to see a huge difference, even with large crops. I've heard of some lenses needing + or -8 (or more) to sort out a mis-match between lens and body.

Once you have done the manual focus test using live view, you can test AF by switching off live view, manually moving the focus ring on the lens to make it out of focus, then half press the shutter (or back button if that's the method you use) to activate AF. Do this at least 2 or 3 times (and preferably at different distances from the subject i.e. near and far away, but always aimed at the same part of the subject). Then review the images on your camera screen and compare them (fully zoomed in) by toggling between each shot. If there is a noticeable difference between the MF and AF shots, you will then know that you need to make further micro focus adjustments.

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Old Monday 14th May 2012, 20:26   #14
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I disagree that it should be done at F8, as, everything I have read about the 400 F5.6 suggests that it is very sharp wide open, so there should be no need to stop down.
The lens is sharp at f5.6 but it does improve slightly at f8

http://www.photozone.de/canon-eos/17...review?start=1


That said I generally shoot it wide open :)
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Old Monday 14th May 2012, 20:34   #15
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Agree about the no need to stop down really , mine is razor sharp wide open .
I can see a difference with the MFA applied .
Don't have a problem hand-holding this lens at 1/1000 at all .

Do the bank note test as suggested , make sure you hit the note under the focus point .
Make sure it locks on properly , do not have the focus limiter engaged !

Keep at it Antonio , you will resolve this I am sure .
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Old Monday 14th May 2012, 20:45   #16
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Here is a shot taken under very similar conditions as your stork using the same camera & lens. Neither have sharpening or manipulation whatsoever and the second image is a crop of the first. It was taken at 1000/sec 6.3 @ ISO320 hand held. Your +2 shot looks shaper to my eyes and I would practice using a tripod & the suggestions above.

I'm wondering if the light conditions were not good enough for the shutter speed as there's lots of noise there which shouldn't be that bad at ISO400. Let us know how you get on with the tests.
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Old Monday 14th May 2012, 22:00   #17
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Huge thanks for all of you, guys, really appreciate it. Definitely not using any filters here :)

Can I believe in those photos that Micro Adjustment +2 gives significantly better results? (since I have only that kind of scratchy wall against my balcony). Or should I stick to testing the Text in front of a wall (but this gonna be next day, since it is late now here in Lithuania) :)
Forget shooting brickwork - use the text, doesn't have to be against a wall a door will do. Or anything to keep it perpendicular to the camera sensor. You need plenty of light as you want your shutter speed high enough to eliminate motion blur - I cannot stress enough the tripod must be robust and up to the job of keeping the camera stable.

I can understand what Steve is saying in testing MF first - but that again will be subject to you interpreting the image in live view to achieve a perfectly focussed image.

Personally i'd stick with the camera in AF - In most cases the issue is not the equipment but rather technique of the user. It's literally a 2 min test. Get the text on the wall / door, aperture at f8 and take the shot or a burst of shots - if the text is sharp - its not the camera / lens its something else..

If the text is not sharp then you can start eliminating whether its the body or the lens using similar tests - but let us know the answer to the AF test of text on a wall first.....
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Old Monday 14th May 2012, 22:18   #18
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I agree with this to a certain extent, but if the shots are still soft it might only reveal something about the autofocus of the lens, or, more specifically, if it is working well with your camera body. If the AF is out, at least with the 7D you should be able to micro focus adjust the lens to your body. I disagree that it should be done at F8, as, everything I have read about the 400 F5.6 suggests that it is very sharp wide open, so there should be no need to stop down.
Steve - The OP needs to eliminate whether there is an issue with the camera / lens or not. The fastest way to do this is to do the AF test first, its a 2 minute job, plus there is no added manual element in the equation. If the text is sharp - its not the camera, job done.

Additionally the test is not only proving AF of the lens - its proving AF of the lens and the AF sensors in the camera - the only way to physically prove lens or camera is to do the same test with a different lens. MF relys on the operator and to be honest there is no baseline to measure against unlike the AF module in the camera, what your eyes think is bang on may not be the same as the next person.

Regarding stopping down, as you are probably aware, every lens has a sweet spot and it is never 'wide open' stopping down to f8 will help achieve a proper result.

Anyway - OP asked for help and i gave it, hope it works out for them...
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Old Monday 14th May 2012, 22:41   #19
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It looks like a mixture of heat haze, high iso, to far away and to slow a shutter speed to me .
Each of these will lose a bit of detail on there own and all of these togather will just give a record shot .
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Old Tuesday 15th May 2012, 07:23   #20
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vipantonio, it looks to me that your lens is either front or back focus, try your MA to correct it. Also if possible, get nearer to the birds
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Old Tuesday 15th May 2012, 07:31   #21
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Thanks guys, I'll try to test it soon.
Quote:
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<...> 500 ISO is not a good choice. It is an underexposure in camera at 400 ISO followed by a 1/3 digital push to bring the brightness up to match a 500 ISO equivalent <...>
tdodd, are You sure about this statement, that 500 ISO is way worse than, let's say, 400? I thought that ISO till 800, or even 1250 is very usable in 7D... Does it mean I should refuse using 1/3 increase, and use only 100, 200, 400 etc?
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Old Tuesday 15th May 2012, 08:06   #22
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Originally Posted by vipantonio View Post
Hello, I'm newbie here :) My Canon EOS 7D + Canon 400mm f/5.6 L BIF photos are soft.

I have read many threads, including this one, and wonder if you could tell from these pics if this is SS problem, or miss focus, or stupid photographer :) ?

I was shooting using One Center Point, AI-Servo mode, High burst rate, Hand-held, RAW. F/7.1, 1/800 sec, ISO 500, 400mm fixed lens mentioned before. Photo on the left is exported directly from Lightroom 4 RAW file, resized to 800px, no sharpening. Photo on the right is 100% crop while zoomed in lightroom and print-previewed, saved fom within Paint program as JPEG.

One more question: how can I check whether I definitely shot in that mode, check Focus point (CF card is already formatted). Thanks

P.S. I have some Bird In Flight photos which show similar results. Should I attach them?
The Lapwing was shot in Av as seen from the exif data -

Original date/time: 2012:05:13 13:45:12
Original date/time subsecs: 17
Exposure time: 1/800
Shutter speed: 1/800.00
F-stop: 7.1
ISO speed: 500
Focal length: 400.0000
Flash: Not fired
Exposure mode: Auto
White balance: Auto
Aperture: 5.6556
Exposure bias: 0.3333
Metering mode: Pattern
Exposure program: Aperture priority


In the main I use the centre focus point as well - but it does have to be over the bird.

With both the Lapwing and the Stork the centre focus is not the bird - it's on the background which does look to be properly in focus and therefore sharper. So I think mis-focus is the main issue for both photos.

I wouldn't rule out atmospherics as well as I've noticed similar issues which I put down to so much moisture being around.

I'd still do a focus test similar to what Derek suggests, though there's a few ways to do this. I'd be inclined take a few at f5,6 as this is a very sharp lens wide open and really it's the point of focus that needs checking as much as a wider depth of field.

Personally I prefer to use ISO200 or ISO400 with the 7D though I regularly use higher including ISO500. ISO500 for the Lapwing shouldn't be an issue here nor the 1/800 sec shutter speed.

Was there a filter fitted? I don't have a problem with using a filer provided the lens hood is extended fully and direct light not straight into the lens, else glare can be an issue.

I think really you need to do the test photos with the light source (sun) behind you to check autofocus I think the issue here maybe down to technique.
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Old Tuesday 15th May 2012, 08:06   #23
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hi, all the advice given is good advice. Just to add was the shot image taken as a single shot in high speed mode, or was it one shot of a burst at high speed? We're there any other shots taken of the subject? Have you any other comparison shots, ie same day and time? Regards
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Old Tuesday 15th May 2012, 08:14   #24
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Thanks guys, I'll try to test it soon.


tdodd, are You sure about this statement, that 500 ISO is way worse than, let's say, 400? I thought that ISO till 800, or even 1250 is very usable in 7D... Does it mean I should refuse using 1/3 increase, and use only 100, 200, 400 etc?
Not WAY worse, but a BIT worse.

It has been very widely discussed (based on detailed testing and analysis by others) that all Canon DSLRs with the exception of the 1 series (not sure about the 5D3) only implement analogue signal gain for the whole stop ISOs of 100, 200, 400, 800 etc.

Each ISO value available on the camera which is 1/3 stop brighter than those standard ISOs (125, 250, 500, 1000 etc) is achieved by a digital brightening of the data within the camera, simply by multiplying each pixel value by a factor of 5/4. As a raw shooter this is something you could do for yourself in software, leaving an extra 1/3 stop of highlight headroom at the point of data capture.

For each ISO value available at 1/3 less than the standard values (160, 320, 640, 1250 etc) the camera captures the image initially using analogue gain at the higher standard ISO value and then reduces the brightness digitally by a reduction in pixel brightness values by a factor of 5/4. This means that you have more analogue gain applied to begin with and then the file is pulled back digitally. Put another way, the camera is giving your exposure (the capture of photons) a 1/3 stop boost to the right because it would be metering, for example, for an ISO of 640, but actually capturing the file at 800 ISO before pulling it back down again.

The consequences of this behaviour is that you may well find that 640 ISO can produce a cleaner file than 500 ISO, but as a raw shooter I see no point in having the camera apply digital pushing and pulling for me. I'd rather shoot at the full stop ISOs and fine tune any further tonal shifts for myself in Lightroom. It's for this reason that I have my cameras set only to use full stop ISOs.

If you search Google for something like canon fake ISO or canon intermediate ISO I'm sure you'll be able to track down some more robust evidence than my say so. There is a typical discussion, but not hard evidence, here - http://forums.dpreview.com/forums/re...1&changemode=1 - but I have seen in depth analysis in the past.

Alternatively, just try some experimentation for yourself, say picking a suitable target with a range of tones from dark to light and shooting it at, for example, 400, 500, 640 and 800 ISO, adjusting shutter speed to suit, and then comparing noise between the images. To be honest you may not see a vast difference from one ISO value to the next, but if you're chasing every last drop of IQ then every little helps. And if 640 ISO really is cleaner than 500 ISO then why not take full advantage of that fact, either by raising shutter speed by another 1/3 stop or stopping down another 1/3 stop. Better yet, for noise, use 640 ISO and instead of raising shutter speed or stopping down to compensate then just allow the exposure to be 1/3 stop brighter, nudging the exposure further to the right. This won't work for subjects and scenes with important bright highlights, but for grey/brown birds in a field of grass I would expect to see a worthwhile gain. The best thing to do is to try these things for yourself and know for certain what works best for you, or if it's all a storm in a teacup.

Whatever you do, do not enable HTP. That will immediately create a 1 stop underexposure and then apply a much larger digital push to restore the shadows and midtones to where they ought to be. Shooting at 500 ISO with HTP enabled would be a very poor choice of settings IMHO. I also understand that ALO can contribute to the appearance of noise, by digitally adjusting your curves for you if it thinks your file needs it. If you shoot to JPEG or use DPP to process your raws then ALO might have an impact. If you shoot raw and use Lightroom then ALO won't make a difference, but HTP always will.

EDIT : I just tried tried firing off a test shot at 1/500 and 250 ISO vs 1/640 and 320 ISO. No edits. Considering the 1/3 stop gain in shutter speed I can't say I notice a deterioration in IQ in the shot with the higher ISO value here....
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Last edited by tdodd : Tuesday 15th May 2012 at 10:42.
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Old Tuesday 15th May 2012, 09:32   #25
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Furthermore, at the risk of labouring the issues surrounding exposure, noise and ISO value, I'd like to present this pair of images from my 7D, viewed at 100%. The shutter speed and aperture are the same for both, as is the lighting. That means that both shots captured the same number of photons and the sensor was saturated equally in each.

However, one was shot at 100 ISO (very underexposed) and pushed in Lightroom and the other at 3200 ISO (somewhat overexposed) and pulled back in Lightroom. Which is the cleaner file? Well to my eyes the shot at 3200 ISO looks far better than the one at 100.

While this is a hugely extreme example it is akin to an underexposure at 400 ISO, digitally pushed to 500 ISO vs an overexposure at 800 ISO, digitally pulled back to 640 ISO, but on a much more dramatic scale.

I think ISO is one of the most misunderstood elements of digital photography. High ISO does not contribute to high noise. Raising it actually helps reduce noise when your sensor is undersaturated. You just need to know which ISO values are good (the full stop ones) and which ones are bad (the fakes).

The best way to the cleanest files is....

1. Capture as much light as possible through your chosen combination of shutter speed and aperture;
2. Raise the ISO as far as you can, in full stop increments, without clipping important highlight details, in order to compensate for any underexposure of the sensor.

This is classic ETTR.

High ISO is not your enemy. Used wisely it is your friend. Just be sure to pick the right friends. :)
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