GemiZ

[Blair S. Paulsen]

:beer:

Cheers - #19

 

[Chris McKechnie]

Standard...standard...standard. Trust me on this.

 

[Phil Holland]

My personal and rather deeply tested opinion regarding OLPFs.

- Standard is named accordingly and should likely be on your camera most of the time.
- Low Light Optimized has about a 3% light transmission gain on the Standard, so it's pretty negligible, but if you need to shoot into the dark it's there for you.
- Skin Tone - Highlight protects you from point sourced artifacts at deeper stops a bit more at the cost of about 1 stop of sensitivity.

General rule of thumb. If you rate your camera at ISO XXXX with the Standard or Low Light OLPF, when you go to the Skin Tone - Highlight OLPF rate it 1 stop lower in ISO for approximately similar noise profile.

And I know we'll get here eventually. When you swap OLPFs you don't need to run a Sensor Calibration.

However, with Gemini in particular it is good to run a Sensor Calibration when you are working with each Standard or Low Light Mode.

 

[Zeb B]

Well now that I have 3 of the most knowledgeable RED resources on the line . . . what about the practical benefit of Low Light Mode v Standard? At what point to you switch over? ISO1600+?

 

[Chris McKechnie]

Well now that I have 3 of the most knowledgeable RED resources on the line . . . what about the practical benefit of Low Light Mode v Standard? At what point to you switch over? ISO1600+?

Yea..I typically switch over at around 1600 ISO. As Phil said, remember to black shade at various exposures for both standard and Lo Light Modes. Still go about manual blackshades right now...auto still doing some weird things when looked at closely. Remember, enabling LLO mode, you lose some highlight range, but typically, you're not worried too much about that anyways when shooting crazy low-light.

Just don't starve the sensor for light and you should be fine. Just because you can shoot at 12800 ISO, doesn't mean you should. haha

 

[Zeb B]

Yea..I typically switch over at around 1600 ISO. As Phil said, remember to black shade at various exposures for both standard and Lo Light Modes. Still go about manual blackshades right now...auto still doing some weird things when looked at closely. Remember, enabling LLO mode, you lose some highlight range, but typically, you're not worried too much about that anyways when shooting crazy low-light.

Just don't starve the sensor for light and you should be fine. Just because you can shoot at 12800 ISO, doesn't mean you should. haha

Thanks! What have you found the Gemini ISO ceiling is for commercial work? Going to run some tests but would like to hear your guys working knowledge

Ditto for RC upper range

 

[Blair S. Paulsen]

I'd be particularly interested in knowing the real world delta between S/N ratios of STD and LLO at equivalent ISO. If it's as small as I suspect, then Standard all the way. If the LLO really does open up shadows by a full stop or more, without needing to push ISO in RAW development... Then the idea of the LLO with fast primes for otherwise un-shootable light levels gets more interesting. If it's only 1/2 stop or less, I'd rather have the better color precision of the STD going into CC. In the meantime I'll try and get by with my good 'ol Monstro and T1.5 Sigmas :coolgleamA:

Cheers - #19

Dang Gemini come lately peeps, trying to steal the Monstro thunder (muttered sarcastically - I kid the Zeb, I kid...)

 

[Phil Holland]

Well now that I have 3 of the most knowledgeable RED resources on the line . . . what about the practical benefit of Low Light Mode v Standard? At what point to you switch over? ISO1600+?

I am a Monstro man, but I've worked with Gemini a smidge. I do one of two things.

Stick in the Low Light Mode most of the time and ND for funzies.

Or have both modes on the fly and watch my Exposure Meters. That's sort of when you know.

 

[Blair S. Paulsen]

I am a Monstro man, (snip)

Or even a "Monstro, Monstro Man... I'd like to be a Monstro Man, etc... :crazy:

Cheers - #19

(Apologies to the Village People)

 

[Zeb B]

Thanks guys! So is there any science or tests about the exact diff between LL and Standard Modes posted? I'm with Blair on the concept of if there's a 1/2 stop of noise floor compromise for a higher color fidelity then go with Standard OLPF and Standard Mode. But then Philly Dawg says "Nah, use the LL Mode brah"

 

[Zeb B]

Shouldn't the RAW/LOG toggle view show me a RAW view that is unaffected by ISO setting? I want to monitor the RAW view without metadate effects

 

[Phil Holland]

Thanks guys! So is there any science or tests about the exact diff between LL and Standard Modes posted? I'm with Blair on the concept of if there's a 1/2 stop of noise floor compromise for a higher color fidelity then go with Standard OLPF and Standard Mode. But then Philly Dawg says "Nah, use the LL Mode brah"

I can explain it pretty simply:

RED Gemini features Dual ISO Sensitivity Modes for Standard and Low Light shooting conditions.

The main difference between Standard and Low Light ISO modes is where you're Base ISO lands.

For Standard Mode, your Base is around ISO 800.

For Low Light Mode, your Base is around ISO 3200. A two stop gain into seeing into the shadows at the slight cost of about 1/2 a stop of Total Captured Dynamic Range.

So essentially you have a Gemini sensor technology that captures 16.5+ stops of Total Captured Dynamic Range in Standard Mode and 16+ stops of TCDR in Low Light Mode and the ability to photograph ghosts in the dark.

 

[Phil Holland]

Shouldn't the RAW/LOG toggle view show me a RAW view that is unaffected by ISO setting? I want to monitor the RAW view without metadate effects

Gioscope gives you the raw feed, Raw View as far as I know is just a Log View now. Need to double check my menus though.

 

[Zeb B]

Gioscope gives you the raw feed, Raw View as far as I know is just a Log View now. Need to double check my menus though.

Thanks! How do you monitor exposure exactly? Probably a better question

 

[Aaron Lochert]

As a Helium owner my experience with OLPFs is this: Standard just about all the time. And if I am shooting a deep stop into the sun, then I'll switch over to the STH to avoid red orbs. The LL OLPF stays in its box and never gets touched. I can't imagine this changes much with Gemini. And with LL mode, I'd probably have even less incentive to grab the LL OLPF.

As far as the Low Light mode on the camera, it is my understanding that if you compared 3200 ISO regular to 3200 ISO LL mode, you would have the same mid-grey, but the highlights will clip two stops sooner, but the shadows will open up nearly two stops more, moving the noise floor down two stops with it. Basically it's how people originally thought ISO worked on these cameras. They thought they could see into the shadows more, when in fact it was merely a gamma curve lifting the shadows along with the noise. Now, it's actually providing more voltage to the sensor (I think) and it's actually seeing detail that was obscured by noise previously.

So in your case, now that I think about it, using LL mode when shooting 96fps sounds exactly right. You're shooting two stops under when going to 96fps when compared to 24fps. So Standard mode 24fps ISO 800 vs LL mode 96fps 3200 ISO should be very, very similar images. What we traditionally would have had to do was open up the lens two stops to compensate or remove 2 stops of ND. Now, you literally just flip a switch and the camera is two stops more sensitive to light.

I really want to try a Gemini. I hope we get one down here in southern AZ sometime soon.

 

[Phil Holland]

Thanks! How do you monitor exposure exactly? Probably a better question

Me personally, through judicious use of the In Camera Exposure Tools (Stop Lights, Raw "Goal Post" Meters, and Histogram) often dipping into Video Check and Gioscope when I feel it's needed. I have covered this on REDuser and within the Field Ops Guide pretty extensively. Still relevant for the most part with DSMC2 cameras.

Outside of that, when I pre-light I use a meter.

I'm a pretty traditional DP and base my exposure logic around knowing where and what 18% Gray is and going below or above key from there.

 

[Zeb B]

Me personally, through judicious use of the In Camera Exposure Tools (Stop Lights, Raw "Goal Post" Meters, and Histogram) often dipping into Video Check and Gioscope when I feel it's needed. I have covered this on REDuser and within the Field Ops Guide pretty extensively. Still relevant for the most part with DSMC2 cameras.

Outside of that, when I pre-light I use a meter.

I'm a pretty traditional DP and base my exposure logic around knowing where and what 18% Gray is and going below or above key from there.

Thanks! Does your Field Op publication include Gemini? Just seriously digging back into RED cams again this week

 

[Phil Holland]

Thanks! Does your Field Op publication include Gemini? Just seriously digging back into RED cams again this week

It doesn't, I haven't made a new version since Gemini has been released, but that specific topic and many other topics are pretty relevant to this day. RED didn't go out and change exposure tools wildly.

 

[Zeb B]

It doesn't, I haven't made a new version since Gemini has been released, but that specific topic and many other topics are pretty relevant to this day. RED didn't go out and change exposure tools wildly.

Thanks! What light meter do you use or would like to use?

 

[Phil Holland]

Thanks! What light meter do you use or would like to use?

I'm using the Sekonic 858 as of late. I've got a few though.