[jvanmetre]

JD-

I think a number of the issues I've experienced with 1.7 are possibly related to the changes to the camera.

EV is now an option -- it's something that was not adjusted (at least manually) in earlier versions. How does EV relate to earlier camera settings?

Thanks.

jvm

[JDHill]

Hi jvm,

EV (Exposure Value) is basically a way of expressing the exposure of the camera, given its' current fStop, shutter, and ISO. It is not a parameter which is written into the MXS; rather, it is just basically a calculator built into the plugin, which may be used to set the exposure in an easier way. So, there is no mystery as regards the rendered result - whatever the fStop, shutter, and ISO are when you export, they act no differently than they would have in the absence of the EV parameter.

The most basic reason why EV is present is to facilitate a true auto-exposure: it acts as the pivot number. That is, given an arbitrary exposure, you know that raising fStop will darken the image, and that you could compensate for this by lowering the shutter. The question would be, how much? If you changed the aperture from f5.6 to f8, how much do you need to change shutter to maintain exposure? How much again when you go from f8 to f12?

Well, EV is constantly figured by the plugin when auto-exposure is off, so as you moved the fStop, you would see the EV number changing. When you then adjusted shutter to compensate, you would see EV moving once again - when it reaches the point it was at before you adjusted the fStop, you will find that the exposure of the image is now what it was to begin with.

What does that mean? Well, if you disable auto-exposure, then adjust the camera's settings, you can 'lock' in the exposure you've gotten to by enabling auto-exposure; once you do, then the camera will use the camera's current EV value to keep the exposure consistent when any further changes are made to fStop, shutter, or ISO.

Furthermore, if auto-exposure is enabled, you can simply use EV to adjust the camera's exposure. There are charts available for determining basic EV ranges for different lighting situations. You can find alot of info on this using Google, for example, the links mentioned in the plugin help:

http://en.wikipedia.org/wiki/Exposure_value
http://www.chem.helsinki.fi/~toomas/photo/ev.html
http://www.cs.mtu.edu/~shene/DigiCam/Us ... rview.html

It is not really possible that this new parameter, or the fact that you can adjust it, will contribute to any bad effects in your images - the image is still created using fStop, shutter, and ISO. If you turn off auto-exposure, and don't mess with EV directly, the camera will behave exactly as it has done in plugin versions which did not have these helper tools. It was not adjustable in the previous version, simply because I had not yet worked out the logic to allow you to use it to drive exposure directly.

JD

[jvanmetre]

JD-

Thanks for the reply. Was working with camera settings yesterday and ended up with some wacky adjustments which lead to some experimenting with the camera. Think I've got a better handle on it.

jvm