Jump to content

M240 ignores minimum shutter speed (aka Max Exposure Time)


Recommended Posts

Advertisement (gone after registration)

Hi all,

 

New to the forum, but not to Leica (M7 and M8 owner).

 

I took the plunge on a new M240 with updated firmware and am a little vexed by the minimum shutter speed functionality when shooting in non-manual "A" mode with auto-ISO.

 

Under SET>ISO>Automatic, I have the maximum exposure time set to 1/(2x focal length). I have a 50mm lens on the camera, but it's not 6-bit encoded. I have the Lens Detection set to manual and I've selected a 50mm lens (50 f/1.2 11820). With the shutter speed dial at "A", I would expect that the camera wouldn't select a shutter speed less than 1/100 unless the ISO was at the max, so why would it shoot at ISO 250 and a shutter speed of 1/45 seconds?

 

Maybe I've been shooting Nikon and Fuji too long, but my experience suggests that the camera should assess lighting conditions for optimum exposure, if too low, it should lower shutter speed to the minimum, and then raise ISO if it still couldn't optimize the exposure.

 

Am I missing something?

 

Thanks for any help.

Link to post
Share on other sites

[...] Under SET>ISO>Automatic, I have the maximum exposure time set to 1/(2x focal length). I have a 50mm lens on the camera, but it's not 6-bit encoded. I have the Lens Detection set to manual and I've selected a 50mm lens (50 f/1.2 11820). With the shutter speed dial at "A", I would expect that the camera wouldn't select a shutter speed less than 1/100 unless the ISO was at the max, so why would it shoot at ISO 250 and a shutter speed of 1/45 seconds? [...]

Welcome to the forum :). You may wish to press "SET" twice after setting the "Maximum Exposure Time". Does this solve your problem?

Link to post
Share on other sites

  • 2 weeks later...

The "Maximum Exposure Time" is actually not a hard limit, but the maximum ISO is. This works the same way on the Fujifilm X100s.

 

What it actually means is the maximum exposure time until the Auto ISO is maxed out.

 

So if your exposure is 1/60 and maximum ISO is set to 3200, but your scene is one stop too dark, it won't go beyond ISO 3200 but instead will ignore the maximum shutter speed and go to 1/30s.

 

In other words, auto ISO won't allow the camera to underexpose despite setting the maximums on both settings. This obviously goes against what most people would expect. If I say don't go above 1/125th, it still does at the last resort anyway...

 

¯\_(ツ)_/¯

Link to post
Share on other sites

Nick is quite correct, you do still have to pay attention to the light and your settings, but when the camera has run out of options it will override them to make sure you still get some sort of image. What would the option be, not allowing the shutter to fire when the limits have been exceed, now wouldn't that be frustrating with the shot of a lifetime?

 

Steve

Link to post
Share on other sites

Did you set a maximum ISO? If you didn't the max auto ISO may be set at 250.

 

Gordon

 

I do - 6400 - but it still occasionally gets it wrong when ISO is less than the max. Never badly: 1/45th chosen with a 50mm lens. I just wondered if it ignored the "2x" and chose the nearest to 1/FL. But as I said, it hasn't worried me enough to investigate deeply. One day I'll screw up a critical shot and wish I'd been more pernicketty. On the other hand, if it was a critical shot I'd be shooting manual.

Link to post
Share on other sites

Hello, everyone, I think this is a major issue with Leica M240 or the latest firmware. I was pulling my hair out all week trying to figure this out, then posted it here this morning only to find out this is happening to others as well.

 

The problem the OP mentioned is not about how Leica implemented AUTO ISO. I do understand how it's supposed to work. Max ISO is the hard limit, but shutter speed is not (in A mode), but in M mode, Shutter speed is the hard limit as well as ISO, and it will start underexposing once both reach the max.

 

The real issue here is that M240 intermittently will refuse to change ISO and stay way under the MAX ISO set in the menu. It happens in A mode as well as M mode. What is even funny is that when this happens, flash symbol will appear in the VF. The camera thinks that there is a flash on, and will AUTO ISO will stop working.

 

I thought it was my camera. I am still taking my camera to Leica store today, but I am now beginning to think that this is a firmware bug. I don't remember having this issue until I updated to 2.0.1.7.

 

Can anyone else confirm this? The crazy thing is this happens intermittently. Believe it or not, it happens when I put my San Disk Extreme Pro 32GB 90MB/s cards. :-) I've never seen a camera brand that is so sensitive to SD cards.

Link to post
Share on other sites

Nick is quite correct, you do still have to pay attention to the light and your settings, but when the camera has run out of options it will override them to make sure you still get some sort of image. What would the option be, not allowing the shutter to fire when the limits have been exceed, now wouldn't that be frustrating with the shot of a lifetime?

 

Steve

 

The option you allude to would not be the desirable...

 

IMHO, in the extreme conditions, the camera should simply take the shot at the limits set. If I failed to pay attention to the light conditions and camera settings, i.e.: it's really dark out there, then my capture will be under exposed... I can deal with that. (To me this is a lesser problem than having blurry shots due to camera shake...)

 

If the camera can "override" the limits I set, then I don't see the point of having those limits as settable parameters.

Link to post
Share on other sites

Hello, everyone, I think this is a major issue with Leica M240 or the latest firmware. I was pulling my hair out all week trying to figure this out, then posted it here this morning only to find out this is happening to others as well.

 

The problem the OP mentioned is not about how Leica implemented AUTO ISO. I do understand how it's supposed to work. Max ISO is the hard limit, but shutter speed is not (in A mode), but in M mode, Shutter speed is the hard limit as well as ISO, and it will start underexposing once both reach the max.

 

The real issue here is that M240 intermittently will refuse to change ISO and stay way under the MAX ISO set in the menu. It happens in A mode as well as M mode. What is even funny is that when this happens, flash symbol will appear in the VF. The camera thinks that there is a flash on, and will AUTO ISO will stop working.

 

I thought it was my camera. I am still taking my camera to Leica store today, but I am now beginning to think that this is a firmware bug. I don't remember having this issue until I updated to 2.0.1.7.

 

Can anyone else confirm this? The crazy thing is this happens intermittently. Believe it or not, it happens when I put my San Disk Extreme Pro 32GB 90MB/s cards. :-) I've never seen a camera brand that is so sensitive to SD cards.

 

This issue was present in FW 2.0.1.5 --when I first got my camera and I noticed, and remains in 2.0.1.7 --after repair/full update at Wetzlar, and I still notice.

 

I found nowhere in the manual about Max AUTO ISO (set) parameter being a "hard" limit, and Max Exposure Time (set) parameter being a "soft" limit... If someone could point me to the right reference, I'd appreciate that.

 

I also haven't yet figure how the algorithm, works... I've had shots where the Max ISO I set hadn't been reached, yet the Max Exposure Time had been exceeded... :confused:

 

Oh well... until they revise how these limits are dealt with. I'm shooting in manual mode.

Link to post
Share on other sites

Why would anyone let the camera automate both ISO and Sutter Speed variables? It seems like that's asking for dissatisfaction in the compromises that will be made by the camera's operating system for you. Expecting operational perfection in such a situation is naïve.

 

Auto ISO is most useful for the camera in manual mode with a known shutter speed, and the ISO being allowed to adjust to match the meter. That involves fewer compromises that might spoil an image.

Link to post
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...