image sharpness

[chen ray]

hi guys

 

just a comparison of indirect lightings renderings in nxt showing only part of the entire rendered image

 

1. indirect with only day light ( rendered in 2 hours for entire image)

2. indirect with HDRI and 10 % daylight ( a little better with lesser noise)  ( rendered in 2 hours for entire image)

3. old ar3 indirect lighting ( sharp but indirect lighting not as good as nxt) ( rendered in 45 min)

 

for item 1 and 2 a pity i dun have the luxury of time to let it bake for many many hours , wonder if there is any better ways to get something similar to item 3 within a much shorther timeframe.

 

of course i can switch off the indirect lighting which will be so much faster but all the soffit will just look raw .

 

having this problem constantly with lack of time due to dateline . trying to find a balance of speed and quality

 

 

[Ros. Riha]

try to experiment with different HDRIs - it seems some are slightly faster than others...but you will not get such a gain anyway.

[akinlolu olugboji]

For my limited experiences and findings HDRi are meant to stimulate the environmental lighting(shades and shadows including)  from  place they where taken from, so adding sun IMHO reduces/undermine the use of it.

 

Love AR3 even more than 4, but Nxt as you have found out does a whole lot of things more than its predecessors.  Hence the longer rendering time, reduce that and you have to do a lot of post production which my own deadlines cannot even accommodate too.

[Ros. Riha]

 HDRi are meant to stimulate the environmental lighting(shades and shadows including) from place they where taken from, so adding sun IMHO reduces/undermine the use of it

 

Technically you are right.

Each HDRI has its own brightest spot, where the sun was captured. You can put nXt sun to the same (similar) location as in HDRI, run 2 channel rendering and use the sun channel to increase the sharpness and intensity of shadows. From my experience most HDRIs produce too weak shadows.

[akinlolu olugboji]

You can put nXt sun to the same (similar) location as in HDRI, run 2 channel rendering and use the sun channel to increase the sharpness and intensity of shadows.

 

Locating this sun spot is the difficult part for me so I just increase the intensity. Can you or someone walk me through this?

[chen ray]

yo guys thk alot again. =)

[Ros. Riha]

Locating this sun spot is the difficult part for me so I just increase the intensity. Can you or someone walk me through this?

 

create a test model - thin vertical stick on the groundplane. render using HDRI for 1-3 passes. direction of the most prominent shadow tells you where the sun shines from and the length of the shadow tells you how high it is.

[akinlolu olugboji]

Can you post a test model for me. How do calculate the height of the sun from the height of the shadow?

[akinlolu olugboji]

[Ros. Riha]

which HDR are you using?

I would render from the TOP view, not from perspective.

Once shadows are distributed this evenly, let it cook a little moore to see, which ones will disappear first.

From the look of the image posted it seems the most of light (=sun) goes from SSW direction - which corresponds with the length of the shadow.

There is no need to calculate the sun direction accurately - just put it to SSW direction to the appropriate height, corresponding with the time of day and the season (from te HDR itself you can usually tell if it is winter, summer, morning, evening...)

All in all - no need to be too accurate.

[Roy Hirshkowitz]

This is a side-thread everybody.  Start a new thread for this discussion.  I may delete these.

[Roy Hirshkowitz]

Are you using the Path Tracer?  It's often faster than the original engine + indirect for exteriors.

[chen ray]

hi roy tried path tracer, indeed it is much faster !! but as shown here wonder why the glass is rendered black when i need to reflect the surrounding colour ?

 

i have downloaded the lattest version and used on this here