Strange Auto ISO behaviour in A and P

[Martin Fagerås]

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I've discovered that my Q does some weird stuff in Aperture priority and program auto.

 

If all other options if achieving correct exposure are exhausted when both Auto iso and shutter speed is set to a max value, all my other cameras have started to drop shutter speed as a last resort to ensure a correct exposure. 

 

The Q does not, it keeps the max shutter speed even if it means underexposing the image. i don't know if this is normal Leica auto ISO behaviour as this is my first Leica, but i find it odd. 

 

What is even worse is that it shows no indication of underexposing (in A and P mode) the EV meter stays at 0, and the live view shows normal exposure. but the resulting image when played back is underexposed. If i set the same shutter, aperture and ISO values in M mode, the EV meter shows severe underexposure, and as soon as focus is locked in live view the preview goes dark as well before exposure.

 

It seems to me that this is very strange behaviour, personally i usually keep the auto ISO setting to max 3200 ISO and 1/125 sec, and shoot in aperture prio most of the time. I first noticed this as a real world scenario when shooting in a dim bar. 

to expose correctly in that environment i probably would have needed ISO 3200 - f/1.7 - 1/30 (or other combination) My worry is that i went home with 2 stops underexposed images and the camera did not tell me at all that was underexposing the images, giving me an indication to correct it. 

 

If you want to test this yourself, this is a "how to test" scenario:

1) Set the Auto ISO settings to: iso 400 and max shutter to 1/2000

2) set the aperture to f/16 

3) you will see a correctly exposed live view image (and histogram) and no indication of underexposure

4) take a shot and review your severely underexposed image 

[Big T]

Just tried it and found the following:

 

1. The exposure bar (Middle bottom of screen) shows Red bars right across the negative (So way under exposed).

 

2. When you half press the shutter the screen goes dark (Shows the correct exposure).

 

So all works as expected.

 

Oppose my bad. Wrong settings. When I use your settings you are indeed right. 

[jmschuh]

I've discovered that my Q does some weird stuff in Aperture priority and program auto.

 

If all other options if achieving correct exposure are exhausted when both Auto iso and shutter speed is set to a max value, all my other cameras have started to drop shutter speed as a last resort to ensure a correct exposure. 

 

The Q does not, it keeps the max shutter speed even if it means underexposing the image. i don't know if this is normal Leica auto ISO behaviour as this is my first Leica, but i find it odd. 

 

What is even worse is that it shows no indication of underexposing (in A and P mode) the EV meter stays at 0, and the live view shows normal exposure. but the resulting image when played back is underexposed. If i set the same shutter, aperture and ISO values in M mode, the EV meter shows severe underexposure, and as soon as focus is locked in live view the preview goes dark as well before exposure.

 

It seems to me that this is very strange behaviour, personally i usually keep the auto ISO setting to max 3200 ISO and 1/125 sec, and shoot in aperture prio most of the time. I first noticed this as a real world scenario when shooting in a dim bar. 

to expose correctly in that environment i probably would have needed ISO 3200 - f/1.7 - 1/30 (or other combination) My worry is that i went home with 2 stops underexposed images and the camera did not tell me at all that was underexposing the images, giving me an indication to correct it. 

 

If you want to test this yourself, this is a "how to test" scenario:

1) Set the Auto ISO settings to: iso 400 and max shutter to 1/2000

2) set the aperture to f/16 

3) you will see a correctly exposed live view image (and histogram) and no indication of underexposure

4) take a shot and review your severely underexposed image

I´ve discovered this "problem" when my max shutter speed was 1/60, max ISO was 3200 and it was extremely dark. In such a situation the EVF/Display doesn´t show that you will get an underexposed image. The Q took not a longer shutter speed than 1/60. All other cameras (Leica included) take the time for Auto ISO only as switching threshold for the automatic ISO setting and when max Auto ISO is reached it will take longer times. The Leica Q takes the switching threshold also as longest available time.

 

There are two options to solve the problem:

 

1. The Q shows the underexposure before you take the picture (dark EVF or display / shutter speed in a different color or so)

2. The Q behaves like other cameras (from Leica and other manufacturers) and takes the necessary longer shutter speed for a correct exposure

 

The misbehavior (failure) of the Q with both options has been reported to the Leica product manager of the Q, Mr. Kruschewski; a week ago. It is to be hoped, that the misbehavior is solved with the first firmware update.

 

Cheers,

 

Jens