ISO... today

[Chris Gearhart]

I've assumed the same thing about Battlestar Galactica exposing normally. I'd be interested to know the scoop on that one too.

At least it won't be hard for me to overexpose on the RED!

 

[Evin Grant]

Internal pre sensor filtration will screw with the optical formulas of a bunch of lenses. 2/3" cameras are all designed with a filter wheel so all 2/3" lenses are designed to accomidate that extra piece of glass. But cinema and still lenses are not, to put an ND into the Red body would require dedicated lenses that had that optical surface accounted for in thier formula. Gel filters can used behind a lens in these cameras becasue they are thin enough not to impact the optical formula.

 

[Antoine Fabi]

ISO 500 ?

Exellent !

Way easier to add NDs when needed.

and most...it will allow way more natural lighting indoors.

a big plus IMHO

 

[Damien Molineaux]

so are we saying that I wont be able to shoot 100, 200, or 400 ISO with this camera becausse the lowest I can set it is 500?

We're comparing to film here. The sensor has a sensitivity comparable to 500 ASA film. With a movie camera you can change films. With a digital camera, as of yet, you cannot change sensors. Maybe there will be a day when you will have a set of sensors you can choose from, wether you're shooting outside, inside, at night, etc. In the meantime, since you're stuck with one sensor, if the quality is there, it is preferable that it be sensitive. If you have too much light, like in broad daylight, you put in ND (neutral density) filters which allows you stop down and makes the sensor behave like it was a lower ASA.

See Jim Jannard's post here :
http://www.reduser.net/forum/showthread.php?t=3217&highlight=jannard+ND

It says it all.

cheers,
Damien

 

[Evin Grant]

I still say the Singh Ray Variable ND is the way to go, 2-8 stops of ND in one filter. Pick your stop and just adjust your exposure with the filter.

http://www.singh-ray.com/varind.html

 

[Nils Ruinet]

I still say the Singh Ray Variable ND is the way to go, 2-8 stops of ND in one filter. Pick your stop and just adjust your exposure with the filter.

http://www.singh-ray.com/varind.html

Yes... Too bad it's too small for Reds lenses...:sad:
Only 77 and 82mm...
Maybe if enough people were interested, they would consider making larger ones, if it's possible...

 

[HD Hildebrand]

I still say the Singh Ray Variable ND is the way to go, 2-8 stops of ND in one filter. Pick your stop and just adjust your exposure with the filter.

http://www.singh-ray.com/varind.html

That is very interesting. Never seen one of those. Guess you just need to get the larger one and step down rings for the varying lenses? Pro's seem that you only get dirt on one side of the element. Con's - can't just swap out lens and swing matte box back into place. Could be easier then constantly swapping ND's though. Does it "click" in 1/8th increments? Can it easily be bumped to another ND level (making it darker or lighter) in mid scene/shot(s)?

Cheers,
Dale

 

[Poi Boy]

This does look like a great option...have you used one Evin ?
Aloha
-A

 

[GlennChan]

Battlestar Galactica is shot on the CineAlta (F950s I think) with a lot of overexposed scenes. I have always been surprised at the hue and saturation levels in the highlights since the CineAltas typically read differently. I have often wondered if they expose closer to normal and then push it in post to hold some chroma above the knee. Perhaps they just run unusual settings for gamma, knee, etc. Anyone know the scoop?

(From reading a magazine which I forget the title of... got it at NAB for free)
The article mentioned that the knee saturation function on the F900 was very useful to them. (Sorry, I forget the name of that menu setting.)

Normally with a knee, you end up de-saturating the highlights... you can emulate this by playing around with the color curves in Photoshop. So the DSP usually has an algorithm to compensate for this... on Panasonic cameras it's called "HIGH COLOR".

2- In some situations, the knee saturation algorithm can do evil things (as in, the end result doesn't look very good).

 

[jbeale]

Does it "click" in 1/8th increments? Can it easily be bumped to another ND level (making it darker or lighter) in mid scene/shot(s)?

I've never used one but from the Singh Ray website, it seems to be freely rotating and uncalibrated so it's up to you to adjust the exposure to suit. Apparently it is two standard linear polarizers, the attenuation is just a function of rotation, so I'd think you could make your own calibration marks. It goes darker than 8 stops too, but they don't recommend using it there due to issues like color problems.

Since it's based on polarizers, you will see the usual polarizing phenomena like reflections off glass, water etc. going away if the filter is at the matching angle.

 

[Karl H]

We're comparing to film here. The sensor has a sensitivity comparable to 500 ASA film. With a movie camera you can change films. With a digital camera, as of yet, you cannot change sensors. Maybe there will be a day when you will have a set of sensors you can choose from, wether you're shooting outside, inside, at night, etc. In the meantime, since you're stuck with one sensor, if the quality is there, it is preferable that it be sensitive. If you have too much light, like in broad daylight, you put in ND (neutral density) filters which allows you stop down and makes the sensor behave like it was a lower ASA.

See Jim Jannard's post here :
http://www.reduser.net/forum/showthread.php?t=3217&highlight=jannard+ND

It says it all.

cheers,
Damien

Hi Damien

well this is what confuses me because I can choose the ISO on my DSLR. 100-1600. Im pretty sure my canon does not have a native rating of ISO100..... though thats the only explaination i can think of if you're saying 500ASA is the lowest we can go on Red.

 

[Jeff Kilgroe]

I don't think welding glass is exactly "neutral", I'd expect a color shift.

Various types of glass / lenses out there for welding. Most are definitely not neutral, in fact I can't think of any that are even close. Expect a green tint (sometimes pink or amber). And In most situations they are excessive in their light blocking ability to the point where they're nearly opaque or nearly impossible to see through unless you're in very intense sunlight or looking at your welding arc. Pretty cool for watching a solar eclipse. Many new welding shields and glass are using LCD screens or other tech that can change from transparent to opaque (or vice versa) when an electric current is applied. And you know what, this is essentially the tech being employed in those variable electronic ND systems.

I could bring a piece of welding glass or even a helmet with an electronic black-out to LART. Then we could shoot wide open at ISO 1600 in the afternoon sun. :nerd: :biggrin:

 

[jbeale]

well this is what confuses me because I can choose the ISO on my DSLR. 100-1600. I'm pretty sure my canon does not have a native rating of ISO 100....

I'm pretty sure the Canon DSLRs do have a native ISO of 100, for the reasons mentioned earlier. You may have a different definition of "native", but I'm using it to mean, the equivalent sensor response before any gain stages. It is true that Canon DSLR cameras still do really well at the higher ISO settings, and that is a tribute to their low-noise amps and I suspect also noise reduction algorithms.

 

[Jeff Kilgroe]

I still say the Singh Ray Variable ND is the way to go, 2-8 stops of ND in one filter. Pick your stop and just adjust your exposure with the filter.

http://www.singh-ray.com/varind.html

That looks pretty cool. For compact configurations without a mattebox, that's like a no-brainer. I think I'm going to pick one up for my Nikon kit... The 77mm size is a direct fit for the Nikon 17-35mm and 85mm.

 

[Finner]

I usually shoot 50asa outside so 500 is going to need some big big ND. I prefer not to stack if possible. Has anyone ever done a meter test to find what kind of ND you get from welding glass?

So after seeing responses to this I have come to realize that if I don't put a laughing face or a haha people can not tell when I am joking.

 

[Chris Gearhart]

Lead glass from colonial times has worked well for me. (ROTFL)

 

[Poi Boy]

For me as well. (ROTFLLADMFWNO)
-A

 

[Jeff Kilgroe]

So after seeing responses to this I have come to realize that if I don't put a laughing face or a haha people can not tell when I am joking.

That's why I put the :nerd: and :biggrin: after my post. Although, I could still bring a 4x6 electronic weld glass to LART just to do it. :bleh:

 

[Michael Brennan]

Gel wheel

Gel wheel

Internal pre sensor filtration will screw with the optical formulas of a bunch of lenses. 2/3" cameras are all designed with a filter wheel so all 2/3" lenses are designed to accomidate that extra piece of glass. But cinema and still lenses are not, to put an ND into the Red body would require dedicated lenses that had that optical surface accounted for in thier formula. Gel filters can used behind a lens in these cameras becasue they are thin enough not to impact the optical formula.

Great! lets do a filter wheel with gels.

Mike Brennan

 

[Stephen Williams]

Gel filters can used behind a lens in these cameras becasue they are thin enough not to impact the optical formula.

Hi Evin,

If using a wide angle lens wide open you will have to reduce the camera's FFD by 1/3 of the thickness of the gel filter behind the lens. Some Cooke Zooms have a Gel slot in the optical path of the lens, those don't need to be compensated for.

Stephen