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Old Dec 31, 2004, 12:37 PM   #11
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Thank you spark! It's raining today so it's a no go for hockey and camera use outdoors. I will use your instructions on the first clear day.
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Old Jan 1, 2005, 5:21 AM   #12
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Thanks for everyone's comments on the ISO issue. I am quite comfortable with the manual settings but on occasions, other members of the family may use the camera and they only want the auto mode so the Auto ISO would be useful. Other times, I may forget or do not have time to switch ISO settings (sometime every second counts in trying to capture a funny moment).

I got a call from Canon'stop customer rep today (different from the one I spoke to yesterday). He does not seem to be familire with the A95 and he does nothave one on hand to test what I described. He thinks the ISO should work from 50 to 400 automatically when set to the auto ISO mode but he is not sure. There is no mentioning of any limitation in the manual. He will check on this some more but will have to contact Japan.

I ran some more test in the fully AUTO mode. My camera only seem to go up to max ISO 100. Also I did not realized that the shutter speed only drops to 1/8 (not the full 15 seconds as in manual mode or Tv mode).

Like Nikolas, I also like to shoot in P mode, but prefer to leave the ISO in auto if it works the way it is supposed to. In P mode, I am still only getting maximum ISO 50 when set to auto ISO, but the time will go as low as 1 second. (again there is no mentioning of this shutter speed limitation in the manual).

I also tested again in the Tv mode with the ISO set to auto and manually from 50 to 400. I am only getting equivalent of ISO 50 in the auto ISO mode.

Going from ISO 50 to 400 will give methree extra steps to work with. If the Auto ISO worked as it is intended to, for night shots, mounted on a tripot, all I have to do is press the sutter (no use having flash as the subject is too far away) and I can get the proper exposure.

For indoor shots, some time I like to turn off the flash so I can get more natual shots. This also avoidthe double flash -the subjects often close their eyes on the second flash; it is also distracting for kids and they stop doing the intersting thing to look at the camera. Again the three steps can make sufficientdifference forthe shutter speed to avoid hand shakes, or a dark vs bright picture.

Canon also said to me that if I want higher ISO then I can set it manually. But my question to them is, why have an AUTO ISO setting, when it is stuck at ISO 50?

Canon also suggested that the camera is tryig to use the lower ISO to get a better picture; however, this is not a plausibe reason because the camera has already maxed out on the suhtter speed and aperature, and without an increase in ISO, I am getting an under exposed picture.
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Old Jan 1, 2005, 11:31 AM   #13
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That was very good work Bill. I agree with you wholeheartedly. Being a newbie, I'm relying on the ASO to be properly set automatically and am getting dark shots as a result until I get better at changing settings.

Do you know if a firmware upgrade can fix this problem? If not, I just may ask for an exchange....doh.
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Old Jan 1, 2005, 12:56 PM   #14
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Bill_CA wrote:
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Like Nikolas, I also like to shoot in P mode, but prefer to leave the ISO in auto if it works the way it is supposed to. In P mode, I am still only getting maximum ISO 50 when set to auto ISO, but the time will go as low as 1 second. (again there is no mentioning of this shutter speed limitation in the manual).
It's very difficult for a camera to meter a scene accurately when light is this low, and getting the desired results usuallyrequires experimentation. So, many models require you to use manual exposure modes for slower shutter speeds.

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Going from ISO 50 to 400 will give methree extra steps to work with. If the Auto ISO worked as it is intended to, for night shots, mounted on a tripot, all I have to do is press the sutter (no use having flash as the subject is too far away) and I can get the proper exposure.
Maybe, maybe not, depending on how low the light is. Exposures of many seconds are not uncommon for cityscapes, etc.

In any event, the recommended way to take night photos is to set the ISO speed to it's lowest value. Users with models that do automatically increase ISO speeds usually set their cameras to use a fixed ISO speed at the lowest setting the camera allows for night photos using a tripod. Using a lower ISO speed helps to keep noise levels from being as objectionable.

Although your Canon is equipped with a Dark Frame Noise Reduction System for longer exposures (1.3 seconds or longer), it's going to be more reliable at lower ISO speeds (a camera will have more hot pixels when ISO speeds are increased on longer exposures, so it becomes more difficult to map them out).

Dark Frame Noise Reduction works by taking two photos (one simulating the lens cap being on). It then looks at the hot pixels in the dark frame exposure, and maps out the hot pixels in the actual exposure. It knows where to find them since the exposure times are identical, and hot pixels tend to show up in the same place on the actual exposure. CCD's tend to have a lot of hot pixels on longer exposures. You just don't see them due to the way the dark frame noise reduction works.

But, at higher ISO speeds, this method of noise reduction is not as reliable. You also have MUCH more random noise, which the dark frame subtraction is not designed to remove. So, you'll have more degradation of detail when using higher ISO speeds. That's why lower ISO speeds are recommended for night photos using a tripod -- you get the benefit of less random noise, and more accurate reduction of hot pixels via dark frame subtraction.

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For indoor shots, some time I like to turn off the flash so I can get more natual shots. This also avoidthe double flash -the subjects often close their eyes on the second flash; it is also distracting for kids and they stop doing the intersting thing to look at the camera. Again the three steps can make sufficientdifference forthe shutter speed to avoid hand shakes, or a dark vs bright picture.
For indoor photos of non-stationary subjects (i.e., people), you're better off using the flash with the vast majority of compact digital cameras. Otherwise, you'll have motion blur at lower ISO speeds and/or objectionable noise levels if you increase ISO speeds.

I respond to many posts from users complaining that they can't get good photos indoors without a flash using a non-DSLR model, complaining about one or both issues (motion blur or noise) when they try.

Quote:
Canon also suggested that the camera is tryig to use the lower ISO to get a better picture; however, this is not a plausibe reason because the camera has already maxed out on the suhtter speed and aperature, and without an increase in ISO, I am getting an under exposed picture.
I've seen this topic debated before (not just with the A95, but with other Canon models, too). It's by design. Youcan debate whether it's a good design or a bad design either way (there are pros and cons to both approaches). But, it's unlikely that they'll change it with any kind of firmware upgrade.

My Konica KD-510z has the same design (ISO speed set to 50with Auto ISO if flash is forced off). This keeps noise levels down, so image quality is much higher. It also has similar limitations on shutter speeds allowed in autoexposure modes (again, it's very difficult to meter a scene when light gets low).

Like your A95, you can change it if desired to use a higher ISO speed. But, I'd only do this if there is no other alternative (since noise can degrade detail in an image).

Look at it this way... With a film camera you'd need to change film to get a different ISO speed (a.k.a., ASA speed). But, with a Digital Camera you simply change a setting. So, it's not really that big of a deal if you run into circumstances where you prefer a higher ISO speed. Simply set it asdesired.


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Old Jan 1, 2005, 2:15 PM   #15
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Happy New Year!

Nicolas, I read that with ISO set to auto, you are getting equivalent of ISO 50 in P mode, and equivalent of ISO 50 – 200 in full Auto Mode. If that is the case, then my camera may be defective.

I took some comparison shots to show what the differences are in various settings with no flash. The 1st shot is P mode & Auto ISO (the shutter speed and aperture have hit the limit that the auto function can offer so the image is under exposed). The 2nd shot is P mode & ISO 50. The 3rd shot is P mode & ISO 100. The 4th shot is P mode & ISO 200 (correct exposure and grain is acceptable) and the 5th shot is P mode & ISO 400 (this one is a bit grainly but shutter speed increased meaning I have sufficient margin to shoot in lower lighting). The last shot is in full Auto mode (equivalent exposure to manual ISO 50, auto shutter and aperture have hit the limit – too dark, I rather live with the grain).

Jim, Don't get me wrong. I love the beautiful photos I get most of the time with the A95 and can live with this design (fault?) because I want the other features. But if this is a defective with my camera then I can go change it for another one while the store still honor the over the counter exchange. I already exchanged it once because the first camera's orientation sensor did not work in one direction.

I like to hear if others are also getting the same problem (or not) with the Auto ISO which can help me determine if my camera is truly defective – Canon has so far not been able to tell me this.

Pulp, I don't know enough about this camera to know if it is possible to do firmware upgrade. I agree with Jim that the chance of a firmware upgrade is slim. You may have to decide if you want all the features that this camera has to offer or look for something else. I will ask Canon when he calls back next week and let you know.

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Old Jan 1, 2005, 2:29 PM   #16
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I want to point outthat the fully auto mode can only go to 1/8 second where as the P mode can go to 1 second. If I do the compensation, this may give the equivalent of ISO 200 as Nicolas found. If this is the case, then the auto ISO may be functioning as designed – although not as I anticipated. Perhaps the manual should be clear on this so buyers can make an informed decision. I will check this out when I have more time – now I have to get ready for the New Year party before my better-half takes away my toy.:G
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Old Jan 1, 2005, 3:51 PM   #17
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Bill_CA wrote:
Quote:
Jim, Don't get me wrong. I love the beautiful photos I get most of the time with the A95 and can live with this design (fault?) because I want the other features. But if this is a defective with my camera then I can go change it for another one while the store still honor the over the counter exchange. I already exchanged it once because the first camera's orientation sensor did not work in one direction.

I like to hear if others are also getting the same problem (or not) with the Auto ISO which can help me determine if my camera is truly defective – Canon has so far not been able to tell me this.

Pulp, I don't know enough about this camera to know if it is possible to do firmware upgrade. I agree with Jim that the chance of a firmware upgrade is slim. You may have to decide if you want all the features that this camera has to offer or look for something else. I will ask Canon when he calls back next week and let you know.


Bill:

It's apparentlythe way it works with the Canon consumer models. I did some digging and found forum threads discussing various models likethe A70, A80, S70, G3, and G5 working the same way (selecting ISO 50 with flash forced off).

Interestingly, some of the Canon reps don't know how it works. So, they've been known to suggest users send in their cameras over this one (whichdoes no good, since the camerasare designed to work this way). BTW, some users havereported that the Sports(fast shutter)Scene Mode (for models so equipped)will boost the ISO speed with flash forced off.





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Old Jan 10, 2005, 3:46 PM   #18
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Here is a summary of sever discussions with the Canon Rep. He tested the features using an A75 in Auto and P modes and he thinks it is working. I have emailed my comparisons (also posted here) to him and he does not know why this is the case. He said he has sent that off to the US support office for assessment (theCanada Repdoes not have an A95 for testing) but it will take a while before anything comes of this. He suggest that I exchange my camera.

Canon confirmed that it is possible to upgrade the A95 firmware.

I also tested this feature out with a friend's A80 camera and found the same problem in the P, Av and Tv modes.

Thanks JimC for your suggestion. I will check out the Sport and Scene mode.

What I have done now is prgram the C mode with the P mode setting but at ISO 200. It is easier to tell my wife that for dark room with out flash, use the C mode rather than pressing all the various button steps.
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Old Jan 17, 2005, 7:42 AM   #19
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Maybe the answer is...:

"The AUTO setting selects the optimal speed. It will automatically raise the speed when the light from the flash is insufficient to illuminate the subject matter."

page 98 Manual PowerShot SD300
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Old Jan 17, 2005, 7:47 AM   #20
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Canon A95 Manual page 89 give you the same answer... :-)
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