custom making my own HDRI,...

[Pongo]

I decided to give this a go, and so far I like what I've been able to make (Quality is low due to my chrome sphere source, but the exposures seem to be working well... getting a better one soon) Once I get this figured out I'll make some higher quality ones and offer them up for download.

I do have something happening with my hdri images though that I do not know how to adjust,... they seem very low and the multiplier needs to be much much higher than what I am used to using in other HDRI images. I was hoping someone that knew more about these could look at mine and suggest what I am doing wrong. (using HDRShop)

edit: problem fixed,... link removed

Thanks.

[Nenad]

Hi Pongo,

I just meant to thank you for sharing your work! And sorry, I'm not able to help you with the exposure issue, although in the past, I have experienced the same problem with different HDR images, sometimes needing to set the multiplier as high as 3.0 for the illumination while keeping it at 1.0 for reflections and envoronment.

Regards,

Nenad

[winberg]

I experienced the same the first time I made an hdri, I had to crank the multiplier to 20 i think....

I figured out the problem though..:

When you assemble your images you should have different a range of different exposures, and the one with "normal" exposure should read as "0" in the list, while your underexposes should be -1, -2 and overexposes should be +1, +2 etc...

Hope this helps, this is what I remember anyways..

-tom

[winberg]

How many exposures did you use for this?

-Tom

[Pongo]

the one with "normal" exposure should read as "0" in the list, while your underexposes should be -1, -2 and overexposes should be +1, +2 etc...
-tom

Ahhh,... this makes sense,.... that may also explain why it always comes up as the darkest exposure also.


I used 13 exposures for this,... actually I think the lowest one was a waste, so I probably only needed 12. Also I screwed it up by only adjusting the shutter speed,... forgot that the camera would compensate by changing aperture. (hence some of the exposures had a different DOF) The next one I'll shoot on full manual control to fix that.

I plan on going out tonight to find a better reflective surface to shoot. Any other comments on the one I made?

Thanks

[Chris_Jones]

For the chrome sphere, ive posted before that is is possible to use the mirror domes that they cover security camera's with, pretty good sphere dome shape and the surface is fairly faultless, could check in some of your local hobby/electrical shops if they have any.
You could probably join two together fairly easily for a pretty good sphere.

Does anyone have a work around for moving clouds, because ive tried doing it with a small digicam, but in the process of changing the exposure the clouds have normally moved, i dont really have the time to use my real manual camera to do it, as its always got a roll of film in it for photography of other stuff.
Any suggestions anyone?

[R2J2]

I had a thought (not that I've tryed it) that I would cut out the clouds (alpha) so that I could animate a time lapse.