Flash Auto-ISO Auto Shutter Speed

Lobalobo · 11-21-2015, 07:39 AM

In a dimly lit room, even with the lens wide open or nearly so, the Q-S1 sets a high ISO, about 1000, and a low shutter speed of 1/20 for a flash image. Manually setting both ISO at 200 and shutter speed at 1/125 produces a much better image, presumably because the TTL control of the camera is increasing the intensity of the flash. Why is this not done by default? Perhaps the highly-powered flash is too hard on skin (I was testing on objects), but then it would seem that the algorithm would go to the high ISO (and, less significantly, slow shutter speed) only when a face is detected. Strange.

reh321 · 11-21-2015, 07:46 AM

Originally posted by Lobalobo

In a dimly lit room, even with the lens wide open or nearly so, the Q-S1 sets a high ISO, about 1000, and a low shutter speed of 1/20 for a flash image. Manually setting both ISO at 200 and shutter speed at 1/125 produces a much better image, presumably because the TTL control of the camera is increasing the intensity of the flash. Why is this not done by default? Perhaps the highly-powered flash is too hard on skin (I was testing on objects), but then it would seem that the algorithm would go to the high ISO (and, less significantly, slow shutter speed) only when a face is detected. Strange.

What camera settings are you using?

**UncleVanya** · 11-21-2015, 10:21 AM

Pentax cameras in Av mode or P mode trend to try to use flash to add soft fill lighting. This happens on the k50 and k3 also.

Lobalobo · 11-21-2015, 10:40 AM

Originally posted by UncleVanya

Pentax cameras in Av mode or P mode trend to try to use flash to add soft fill lighting. This happens on the k50 and k3 also.

Thanks. This might make sense for a larger sensor, but the grain on the Q's tiny sensor at high ISO is disqualifying. As I mentioned, perhaps I can see it for a shot of a person's face, because harsh lighting could be worse than the grain, but there is an easy solution, then, set the algorithm for soft lighting whenever a face is detected but otherwise pump up the flash.

---------- Post added 11-21-15 at 10:41 AM ----------

Originally posted by reh321

What camera settings are you using?

Either P or A.

reh321 · 01-19-2016, 08:40 PM

Originally posted by reh321

What camera settings are you using?

Originally posted by Lobalobo

Either P or A.

Looking back at this thread, I'm not sure that we ever truly addressed your concerns, but the whole question of "settings" involves more than just one dial. The internal programming of a modern camera is a fairly complex automatron that is very hard for one person to fully comprehend, but we can steer it to the behavior we want via the "settings". "Settings" is a whole collection of values set at various points, some things on visible dials and some things on not-so-visible menus. My thinking is that the behavior you are seeing is a result of the whole collection of "settings", and you might see different results under a different collection. For example, the menu setting for ISO can be either a specific value or an allowed range. Most likely the "settings" you were working under included the menu item which allowed ISO to be almost anything; perhaps if you reset the ISO to be only at 200 or lower, you would see the behavior you want without your having to do anything else.

11-21-2015, 07:39 AM	#1
Lobalobo New Member Join Date: Sep 2015 Location: New York Posts: 22	Flash Auto-ISO Auto Shutter Speed In a dimly lit room, even with the lens wide open or nearly so, the Q-S1 sets a high ISO, about 1000, and a low shutter speed of 1/20 for a flash image. Manually setting both ISO at 200 and shutter speed at 1/125 produces a much better image, presumably because the TTL control of the camera is increasing the intensity of the flash. Why is this not done by default? Perhaps the highly-powered flash is too hard on skin (I was testing on objects), but then it would seem that the algorithm would go to the high ISO (and, less significantly, slow shutter speed) only when a face is detected. Strange.

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11-21-2015, 07:46 AM	#2
reh321 Pentaxian Join Date: Nov 2014 Location: South Bend, IN, USA Photos: Gallery \| Albums Posts: 23,177	Originally posted by Lobalobo In a dimly lit room, even with the lens wide open or nearly so, the Q-S1 sets a high ISO, about 1000, and a low shutter speed of 1/20 for a flash image. Manually setting both ISO at 200 and shutter speed at 1/125 produces a much better image, presumably because the TTL control of the camera is increasing the intensity of the flash. Why is this not done by default? Perhaps the highly-powered flash is too hard on skin (I was testing on objects), but then it would seem that the algorithm would go to the high ISO (and, less significantly, slow shutter speed) only when a face is detected. Strange. What camera settings are you using?

11-21-2015, 10:21 AM	#3
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,398	Pentax cameras in Av mode or P mode trend to try to use flash to add soft fill lighting. This happens on the k50 and k3 also.

11-21-2015, 10:40 AM	#4
Lobalobo New Member Join Date: Sep 2015 Location: New York Posts: 22 Original Poster	Originally posted by UncleVanya Pentax cameras in Av mode or P mode trend to try to use flash to add soft fill lighting. This happens on the k50 and k3 also. Thanks. This might make sense for a larger sensor, but the grain on the Q's tiny sensor at high ISO is disqualifying. As I mentioned, perhaps I can see it for a shot of a person's face, because harsh lighting could be worse than the grain, but there is an easy solution, then, set the algorithm for soft lighting whenever a face is detected but otherwise pump up the flash. ---------- Post added 11-21-15 at 10:41 AM ---------- Originally posted by reh321 What camera settings are you using? Either P or A.

01-19-2016, 08:40 PM	#5
reh321 Pentaxian Join Date: Nov 2014 Location: South Bend, IN, USA Photos: Gallery \| Albums Posts: 23,177	Originally posted by reh321 What camera settings are you using? Originally posted by Lobalobo Either P or A. Looking back at this thread, I'm not sure that we ever truly addressed your concerns, but the whole question of "settings" involves more than just one dial. The internal programming of a modern camera is a fairly complex automatron that is very hard for one person to fully comprehend, but we can steer it to the behavior we want via the "settings". "Settings" is a whole collection of values set at various points, some things on visible dials and some things on not-so-visible menus. My thinking is that the behavior you are seeing is a result of the whole collection of "settings", and you might see different results under a different collection. For example, the menu setting for ISO can be either a specific value or an allowed range. Most likely the "settings" you were working under included the menu item which allowed ISO to be almost anything; perhaps if you reset the ISO to be only at 200 or lower, you would see the behavior you want without your having to do anything else.

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