Working with the SL -- questions?

[scott kirkpatrick]

I realized today that autoISO doesn't work as simply in the SL as it did in the Ms. In A mode, when you have too little light to take a picture at the Max ISO and min shutter speed, an M further reduces shutter speed as long as it can provide a meter reading. The SL refuses to further reduce shutter speed (perhaps because it cannot provide a decent image at the taking aperture) and you have to shift to M mode or at least fixed ISO to push it down further. Godfrey had commented on this a while back, but no one related his comments to their practice at that time.

His response

Yes, AutoISO behaves this way in the SL: when you're past the range you've set, you'll get underexposure. When you switch to a fixed ISO setting, the exposure times will lengthen to maintain proper exposure ... up to a point. As you close down the aperture more and more with adapted lenses in low light, you'll run into the range limits of the metering system—at which point you'll get underexposure again. You can see this happening when using Manual exposure mode too. There comes a point where you're past the range limits of the metering system (because it's trying to meter with the lens stopped down) and that ultimately results in underexposure if you follow the meter's recommendations.

With the SL's 24-90 lens, this doesn't happen until you're in MUCH lower light because the lens is held wide open at viewing/metering time, normally.

I wrote about this behavior on the LUF a week or two ago. No one commented. The SL seems a bit tighter on range limits with adapted lenses than some other cameras, but I've seen the same behavior with other cameras to which I've adapted my lenses.

BTW: It would be nice to ask questions like this in threads separate from the "Fun with the Leica SL" thread. Nearly all SL questions and opinions have all been going into just this one thread, which I thought was supposed to be about sharing photos made with the SL like other "fun with ..." threads. Can we put pictures here and discussion/questions/etc into other threads that pertain to the specific topic of discussion?

is worth comments or further discussion.

scott

 

[jonoslack]

HI Scott
I had hardly noticed this behavior . . .basically because I've set the auto iso to 6400 ISO - which is usually okay in really poor conditions.

 

[LocalHero1953]

I'm happy with AutoISO as set up, if I understand the issue correctly. With the M, I would sometimes end up with correctly exposed but blurred images because the M's ISO performance was not as good, because I usually used AutoISO indoors with moving people, and because, at the limit, the shutter speed would be reduced. In the same scenarios, I would rather have under exposure (which I might be able to do something about in post) than motion blur (which I can't).

I have max ISO set to 12500, and I am seriously impressed with the SL's noise management. It's there when you look at 1:1 but is so well disguised at normal viewing scales. Colour noise in particular seems to be minimal.

 

[scott kirkpatrick]

Here's one where it is not clear what the minimum shutter speed would be, because the SL 1.10 firmware has no focal length for the lens. I'm using the Vario-El mar 35-70/wide open at f/4, ISO 3200, 1/20 sec. Reflections --

L1000120 by scott kirkpatrick, on Flickr

scott

 

[Paratom]

I am also fine with the autoiso. With the EVF one can see when exp is too low easily and then, as Jono does, set ISO manually.
An option ("exceed longest set exp time at max ISO when exposure is too low") would be nice, but personally I rather get underexposed images than blurred ones.

auto iso settings is one area where I think Leica is better than Sony.

 

[Godfrey]

It works fine for me now, I just had to get used to a different way of thinking about the exposure system. The range limits only really showed up when I was doing some lens testing because I was exercising each lens from wide open to minimum aperture.

I do wish I could tell the camera what ISO to use as a minimum as well, however. But it's hardly an issue.

G

 

[scott kirkpatrick]

Here's a stress test for the R 35-70/4. Had to crop roughly 50% to concentrate on the panel discussion. The video rig next to me seemed to be using a 100-300. ISO 1600, f/5.6 1/100 sec. Faces are modeled nicely, but not particularly crisp.

L1000143 by scott kirkpatrick, on Flickr

still, it works.

scott

 

[Godfrey]

Here's a stress test for the R 35-70/4. Had to crop roughly 50% to concentrate on the panel discussion. The video rig next to me seemed to be using a 100-300. ISO 1600, f/5.6 1/100 sec. Faces are modeled nicely, but not particularly crisp. ...

It kind of looks like an ISO 400 film image, in its way.

G