Camera results (new)

[Sawyer]

This is an update of what I was looking at last week and a bit of a novice approach (novice for novices).
Not having a set film speed is a bit hard to get used to so I kind of guess. Seemed like an interior could go with an iso 800 so I started there. Stuck with 3.5 fstop for all of these and a 18mm focal.

NOW something that I was wondering is what is the focal length in vray (digital or 35 mm standard)? It is in 35mm units so you need to multiply it by 1.5 to get simular focal length in your DSLR! Keep that in mind 18mm on your digital equals 27 in a 35mm slr. Most of you have figured that out I am sure, I was confused. But that is why I have a different focal length.

I am just doing this so I have a catalogue of examples so I can start with something simular and know what to expect. Also I am trying to figure how to keep the sky without the burnout.

About the file Gamma Correction was done with color mapping inverse gamma.
Top right image is my office and the basis for this series.

If anyone wants to post the file e-mail me and I will send it to you. I have not figured out how to do that yet.


Thanks

[panthon]

I find it difficult to keep interiors and exteriors evenly lighted too. In a real situation u can't keep both ambients well exposed unless u add light to the interior. I guess with the new physical approach would be about the same. If u lower the sun intensity, the same goes to the sky, so the only way to "fake" an evenly lighted scene for both interiors and exteriors is disconnect vraysun from vraysky by activating the manual mode under vraysky parameters. This way u can get a nice light level in the interior coming from the sky AND some sun light entering a room without burning everything in hell.

[SteveC]

I was also wondering how the vray phy camera would handle interior
scenes, I've not done any testing on interiors yet, but my main concern
was weather the vray camera behaves like a DSLR or SLR camera in
these situations.

With the vray phys camera, i try to think like would if i were using a DSLR
or SLR camera. Take sawyers scenes as an example, using DSLR or SLR,
if i focused on those double doors or metered on those double doors the
camera would be set up for that view, so the doors would be correctly
exposed and the room would be dark. But if i focused or metered on an
object in the room, the room would be correctly exposed and the doors
would be blown out or over bright.

Does the vray camera behave the same way? what did you find sawyer?

If i was going to photograph an interior, where appropriate, i would either
use a long exposure time with a tripod, or a flash, if the interior lighting
was'nt bright enough, should we treat the phys vray camera the same
way?

stevec

[Neilg]

With the vray phys camera, i try to think like would if i were using a DSLR
or SLR camera.

Take sawyers scenes as an example, using DSLR or SLR,
if i focused on those double doors or metered on those double doors the
camera would be set up for that view, so the doors would be correctly
exposed and the room would be dark.

This doesnt happen with manual mode on, and anything else on an slr is a cheap workaround/trick.

So yeah, it does work like a d/SLR - if youre using it right.


We really do need a photography sub-forum now.

[panthon]

Ok i ve found that using vraysun + vraysky in interiors give u a very unbalanced illumination compared to old vray-inthewindows trick. Sun light is on but the room looks too dark, as the camera is set to properly expose the exterior.
Here you can see:

LWF, vray physical cam F=4, Shutter = 60, ISO = 200, Focal lenght = 22 mm
Sun intensity = 0.03 and Manual sun node unchecked. That means that vraysun and vraysky are connected. Vraysky at defaults.




LWF, vray physical cam F=4, Shutter = 60, ISO = 200, Focal lenght = 22 mm
Sun intensity = 1 and Manual sun node unchecked. That means that vraysun and vraysky are connected. Vraysky at defaults.



LWF, vray physical cam F=4, Shutter = 60, ISO = 200, Focal lenght = 22 mm
Sun intensity = 0.03 Manual sun node checked Vraysky at defaults.
This way u can correct the sun intensity without affecting the sky light. However, you are losing the ability to automatically tint the light as the sun comes down, for example. Is there any method to keep t without having to choose between exposing for exteriors or interiors?

[ene.xis]

u should keep the sun value at 1 increase the shutter and add light in the interior as u would in a real life situation!

i find this aproach to produce very predictable results!

[panthon]

Adding light is what u would do in real life, but it means adding lights per shot, and these lights wont work from another point of view...If u need to render 40 points of view, do u want to do 40 lighting setups? I am trying to go for productivity and not only quality. Things get even more complicated if you are dealing with animations, because lighting setups can be really tricky with a camera moving along the scene...

[ene.xis]

If u need to render 40 points of view, do u want to do 40 lighting setups? I am trying to go for productivity and not only quality.

u just need to add lights IF u dont want to have an whashed out exterior...therby u have to fake a little and althou it involves some more work its very predictable and u can really get away with it in production...
i m usin it allready...and quite happy with the workflow!

Things get even more complicated if you are dealing with animations, because lighting setups can be really tricky with a camera moving along the scene...

same as before...how would u do it in real life?

[panthon]

If u need to render 40 points of view, do u want to do 40 lighting setups? I am trying to go for productivity and not only quality.

u just need to add lights IF u dont want to have an whashed out exterior...therby u have to fake a little and althou it involves some more work its very predictable

I dont mind exteriors being washed out, but clients are picky with it, i bet u have faced the same problem. Good news about it is that we render interiors and exteriors in separate passes anyway, just because it's more memory-wise, but i was curious about an all-in-one render...Anyway, I prefer to control how washed our exterior is in post.

Things get even more complicated if you are dealing with animations, because lighting setups can be really tricky with a camera moving along the scene...

same as before...how would u do it in real life?

I ve shot many short films and im well aware of the difficulties of hiding light projectors when your camera is travelling or craning around. Besides, it´s hard for directors of photography to avoid hotspots in critical places while some other places are heavily underexposed because there's not enough budget to rent all they would like to or physical space to place projectors! I like to work in 3d because you dont have these limitations and i feel that as soon as you get closer to a physical approach u start facing the same problems a real DP would have. Dont misunderstand me, i like that predictable way of working too, but i would like to take advantage from everything we've got in a virtual world

[re:FORM]

wouldn't vraymaterialwrapper with low receive GI on all external materials and an exclusion from vray sun (use another sun at lower intensity) do the job in one pass?

[ene.xis]

u can always use maxcamera reduce the sun intensity and work as u did before...right?

all in one at this point u just have more options at ur disposal to get ur job done...at least thats the conclusion i got to!
and thats the reason why i m so happy and posting like there s no tomorrow!
the current job is flowing like a charm!

[Neilg]

Dont misunderstand me, i like that predictable way of working too, but i would like to take advantage from everything we've got in a virtual world

Suprised youre trying to use the physical sky then... yeah, its fast, but theres just not enough control and too many issues for any degree of extreme precision.

[ene.xis]

Suprised youre trying to use the physical sky then... yeah, its fast, but theres just not enough control and too many issues for any degree of extreme precision.

not enough control? hows that?

[instinct]

i guess it get's down to the problem that if you want it all physically based, then you'll also have to fight physical trouble, just as in real life hehehe.

In this case wouldnt Reinhard colourmapping, or manual colourmapping via a saved float help ??

Thorsten

[dapeter]

LWF, vray physical cam F=4, Shutter = 60, ISO = 200, Focal lenght = 22 mm
Sun intensity = 1 and Manual sun node unchecked. That means that vraysun and vraysky are connected. Vraysky at defaults.

I'd make a bet if you took an actual picture with the camera set up as you have it (and the sun streaming into to the room at that time of day) that this is what you'd end up with. Try a shutter speed around 90 with that f-stop and ISO setting...

Suprised youre trying to use the physical sky then... yeah, its fast, but theres just not enough control and too many issues for any degree of extreme precision.

I'd also like to know what you're talking about. The physical sun is based off a mathematical model of the actual sun in the sky, and how the atmosphere affects the color. You have to leave it at mult=1.0 if you want predictable results, since this is the physically correct way of doing things. You end up having to adjust the exposure using the camera, just as you would in the real world.