[Tig] Is there anybody out there

[Deanan]

bobineinc at yahoo.com wrote:
> under/over exposure, but do we really want more than 6
> stops of range with poor transition of tone ? Or do
> you want 4 stops to create an image with the proper
> transition of tone ? 
>   
Both. Absolutely more dynamic range and enough sampling resolution to
carry as much of the tone transitions through as possible. Having only four
or 6 stops with lots of tone is great but lose the ability to do any 
remapping
in post and your trade off both shadow detail and highlight 
response/transitions.
Although, you can make the same argument for shooting neg vs. reversal.
> Too much Dynamic range always lacks contrast and the
> colors are muddy like Clark's pictures. Also that
> enormous HDR brightness range makes transition poorly.
>   
That really depends on how you do your tone mapping from the HDR to
a viewing space. You can get as contrasty as you like. It's not much 
different
than compressing your wide dynamic range negative into a lower dynamic range
print stock.
> The question is detail vs graduation?
> Lost of digital  camera manufacturers specify the
> dynamic range without  including the noise.  Why not
> since we don't tolerate noise with film?  How useful
> are those stops past the sixth if we have them coded
> with very few levels? 
>   
We tolerate alot of noise in film because it's very nice noise (depending
on the stock, some stocks have ugly grain). The main differance between
digital and film is that digital tends to have noise mostly in the 
shadows (if
properly exposed) but not elsewhere. Film on the other hand has grain
everywhere. A nice side effect of grain everywhere is an increase in
perceived sharpness without actually being sharper (nice for skintone
because it hides wrinkles and pores).

The extra stops in the highlights are great for making the specular
transitions look nicer (and why digital cameras with not much
latitude have really harsh specular response). At the same time,
more latitude means that you can go into shadows alot more
and still be above the noise floor. Of course, the more you
push the rating on a digital camera, the more you start to bring
out the noise tends to more funky than pushing film.
> All those digital cameras have different amps for each
> channel, and one will always burn out first, or go
> dark first due to different natural color balance,
> it's hard to find true blacks and true whites anywhere
> in nature unless we shoot a target at the perfect
> color temperature, witch mean we get estimated pixels.
>   
With bayer format sensors, it's the inherent color balance of the
sensor's filters that cause the color channels to go out at different rates.
If you sensor is daylight balanced, then your red will by much more 
sensitive
than the blue and will reach saturation much faster than the blue if you're
shooting a daylight balanced scene. Film has the same issues but they're
less apparent because they're compensated for by the shoulder and the
print. A digital camera with a good shoulder and more latitude will get
you more balanced highlights but instead of balancing the highlights
via the print, you have to do it by processing the image.

Cheers,

Deanan
Dalsa