Exposure Chart

[glorybound]

I brought this up before, but I am still fighting it. Why these numbers don't work? I mean, they should. I know I can do it by eye, but when using the VRay Sun/Sky and the VRay Camera, the numbers should get you pretty close.

[squintnic]

thats for real cameras
this is a computer

[Morne]

I've always used this one and it hasn't failed me yet
http://en.wikipedia.org/wiki/Exposure_value
Check Table1

[alexyork]

People often overcomplicate things.

1) Always leave your sun and sky at 1.0.
2) Use real-world values for your internal and external lights (watts, kelvin etc.)
3) Use the default PhysCam exposure value and white balance at Neutral and adjust both as needed, with real-world shutter speed, ISO and aperture values

It really does only take minutes to set up and works every time. You can of course later go in and start using non-realistic/standard values if you need, for some reason, but if you work from this as a base every single image will be predictably lit, at least as a base.

[glorybound]

Sun/Sky at default and using VRay Camera - 100% white

[georgi.zhekov]

You are using f 1.4 and Shutter Speed of 60 - if you use those settings with a real camera in a bright day the result would be the same. If you change the f-stop to 8 or 11 and the shutter speed to 100-200 you will be okay. Still if you would like to use lower f-stop for DOF and longer shutters for the motion blur you need to lower the sun intensity.

[alexyork]

You are using f 1.4 and Shutter Speed of 60 - if you use those settings with a real camera in a bright day the result would be the same. If you change the f-stop to 8 or 11 and the shutter speed to 100-200 you will be okay. Still if you would like to use lower f-stop for DOF and longer shutters for the motion blur you need to lower the sun intensity.

Exactly. I did say in my 3rd point that you need to adjust as necessary. Naturally you need to use real-world values. Think about it from a real camera standpoint - if you're shooting outside on a sunny bright day with sun hitting your building, you'll probably be shooting f11 @ ISO 100 and then a shutter speed of something fairly quick like 100-200 as Georgi said. Just use real values. If it's slightly dull or slightly bright just change the shutter speed. That's literally it.

[dlparisi]

You are using f 1.4 and Shutter Speed of 60 - if you use those settings with a real camera in a bright day the result would be the same. If you change the f-stop to 8 or 11 and the shutter speed to 100-200 you will be okay. Still if you would like to use lower f-stop for DOF and longer shutters for the motion blur you need to lower the sun intensity.

True, but this looks to be an interior scene. Without knowing the lighting in the room though it's hard to evaluate.

[glorybound]

The chart says, "interior with bright sunlight", which what this is. I don't have any interior lights; all sunlight. I understand just changing it as needed, but I feel more comfortable with a baseline. I can see up/down a nudge, but the numbers are extremely different.

[alexyork]

Your aperture is way too low for an interior scene, unless you're going for extremely soft DOF. So put that at something realistic. Again, your settings are not realistic for any photography in that situation. Get those settings in and see. I expect you should find a decent exposure with shutter speed 60, F8-12, ISO100. But for an interior you generally don't expose for the sunlight coming in - you expose for the interior lights, since they will form the majority of the light sources in the view - unless you're going for something without much interior lighting.

[andybot_cg]

lol - Bobby, I think you should get out your light meter and check the illuminance in that room. Seriously, if you don't know very much about film photography, just skip the exposure value stuff. Looks like it's only confusing you.

Another trick though, if you are serious about the f1.4 is to make your ISO value very low - like 10, then you can keep a slower shutter speed.

[Neilg]

scrap all exposure settings, drop your sun power to 0.02, render with low settings and increase the power of the sun from there. when you add interior lights do the same, just see how they look and move from there. you cant get away with just typing in some numbers and getting a good render out first time, you'll always need to carefully balance lights.

I still think using exposure at all is already over complicating what used to be very simple. if a light isn't bright enough, turn it up. if it's too bright, turn it down. no other controls are needed.

[alexyork]

scrap all exposure settings, drop your sun power to 0.02, render with low settings and increase the power of the sun from there. when you add interior lights do the same, just see how they look and move from there. you cant get away with just typing in some numbers and getting a good render out first time, you'll always need to carefully balance lights.

I still think using exposure at all is already over complicating what used to be very simple. if a light isn't bright enough, turn it up. if it's too bright, turn it down. no other controls are needed.

I disagree very much with this workflow, but each to their own! If it works for you, why not I guess.

[eyepiz]

Sun/Sky at default and using VRay Camera - 100% white

[ATTACH=CONFIG]21131[/ATTACH]

That's odd...Here is one of my interior with those settings. I usually keep my shutter speed around 100 and tweak the iso.

[glorybound]

You MAX and VRay Gamma is 2.2, correct? What about your VFB gamma?

That's odd...Here is one of my interior with those settings. I usually keep my shutter speed around 100 and tweak the iso.

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