4k daytime and 2k for night ext?

[Roberto Lequeux]

I am trying to imagine how to get the most out of what will likely be a limited grip and electric package and have been trying with this idea. I am also trying to do this with my limited cinematographic knowledge so any help would be greatly appreciated.

I have one exterior night scene where I would really like to get some depth. Since we'll have very limited power, just a few small generators and hopefully some power from a house, coupled with not so many smaller HMIs... I was wondering if perhaps I could switch to shooting windowed S16 2k as my characters run out the door...

I have a strong feeling that the audience would be quick to accept a slight drop in detail, slight since we'd only be concerned with 1080p Blu-Ray distribution which would make the difference less noticeable. I just don't know how big this difference would be.

So I concluded that the 18mm f1.3 Super Speed we are thinking about renting would give us, on the 2k windowed area, the FOV of and DoF of a 44mm lens set to f3.2 on the 4k area of the Red One, unless I messed up the calculations. We could really walk it back a good 30ft plus to make the most of the smaller 31.4 degrees of horizontal FOV... but would we gain exposure like this? Or am I confusing too many things together? See I am wondering if I could like this keep the lens wide open to get more light while making the DoF deeper... but somehow that seems like it isn't the way things work after taking such a closer look at the numbers...

Can someone help me understand this please? Would there be any way to make DoF deeper without sacrificing exposure?

:pinch:

[David Mullen ASC]

You don't gain any exposure in 2K windowed mode, just depth of field once you've compensated by using a shorter focal length.

Your 18mm lens stays an 18mm lens, but in 2K windowed mode, it loses half its view, so you'd have to switch to a 9mm lens to get the same view, and thus you'd gain 2-stops of depth of field (but not exposure).

If you don't switch lenses, your 18mm lens now has half the view in 2K windowed mode, as if you were shooting in 4K mode with a 36mm lens. But in terms of depth of field, it's still an 18mm lens and you haven't gained any extra depth of field, it's just that compared to using a 36mm lens in 4K mode, you'd have more depth of field.

But 2K windowed mode gives you nothing in terms of ability to shoot in lower light levels -- if anything, should you need to use a higher ASA rating in very low light levels, you're better off in 4K mode because the noise will be less obvious than in 2K windowed mode.

So the only thing 2K windowed mode is really giving you is the extra depth of field IF you compensate by using a shorter focal length to maintain the same field of view. But you can think of it as generally giving you more depth of field, deeper focus characteristics, compared to shooting in 4K mode.

But I think if your main problem is a lack of exposure, you're safer using higher ASA ratings in 4K mode. If you have enough exposure at normal ASA ratings with your fast lens, then yes, the 2K windowed mode would generally give you more depth of field if you compensate by using shorter focal lengths.

[Roberto Lequeux]

Thanks David! It is so easy when you explain it.

So just shoot with the 18mm as much as possible so that I am using the deepest DoF I have available. Perhaps there may be one small benefit to 2k... perhaps... there is an effect that I despise from getting close ups with short focal lenghts, or shoud I say from having objects in the frame close to the camera when using short focal lenghts. I am not sure what this is but it feels as though you are using a fish eye lens. Perhaps this may be that objects close to the lens show the weaknesses of the way a particular lens handles distortion..? Perhaps this is not so prominent on better lenses than it is on cheaper lenses though. However I think I might not benefit from narrowing the FOV of the 18mm just to pull away from my subject... not when I can probably get decent close ups from the 35mm and still manage to shoot wide open without having too much of a focusing dilemma to dump on my AC.

Let me be clear, sorry if I ramble, but I am in the process of learning and I feel the more I talk the more chances to have you guys set me straight and put me back on course:

Do you think that shooting a full scene with the 18mm 25mm and 35mm, all wide open at f1.3, will be both relatively easy and give us good results (no fish eye feel)? Granted that we can expose enough of the snow covered lake and fields around us of course.

This may be too big of a question to ask, I don't know. My guess is that we will certainly manage with the five or six 1.2 par HMIs, and a few kinos, and some tungsten mixed in there.... with a 5000W and 2000W Honda quiet gennys that we will have, plus some juice we will run from the house.

lol... I hope that doesn't sound neither too pretentious to ask or or too discombobulated of a question.

[Conrad Hunziker]

Theres not much easy about shooting at a t/1.3 - you'll need to have a good focus puller no matter what focal length you use. On the 18mm you'll still have a small DoF, which can be compounded if the lens and red arent setup exactly right. Shooting on a 18mm doesnt make it easier per-se, just makes it different.

Consider this also - on the 18mm you'll see more of the background on a similar shot than on a 35mm. For example, say you lined up a medium shot of a guy standing on a 35mm lens and compared that to the same shot on a 18mm. You would see more of the background behind him, so you'd need more lights out there to light the lake/fields. On the 35mm you'd be able to contain the amount of background you'd see, so youd be able to bring up the relative exposure on the background - same amount of lights, closer in.

One more item to consider when comparing the two shots - your camera is physically closer on the 18mm vs the 35mm. So your medium shot (in 2.40:1) on a 35mm @ 5' gives you 3'4" horiz and 1'5" vertically, and a DoF of 4.6" @ t/1.3. However your 18mm has to be 2'7" away from the subject now for that same shot (half the lens, half the distance) and your DoF is 4.7". So for that same shot on a 18mm, you gained .1" DoF.

However, really, it sounds like you are ready to hire a cinematographer and do some location scouts.

[Roberto Lequeux]

Oh yes, I am in no way doing this alone hehe... While I'd like to think that I'd do a decent job that's just not my thing, and decent after pulling all of my hair out is not what I am after. :)

Interesting! Only an additional .1" from the 35mm to the 18mm! I wish I had the money to take a cinematography class, it would be so much fun and so immensely helpful down the line. The better I can understand what my DoP is doing, what he wants to do, and how, the faster we can get to shooting, and the better I can tell my story... and the less I can drive him insane, a happy DP is a better DP. Wouldn't you say? :)

I am going out there soon, while the winter is still raging. I won't be there with my DP, but I plan to be on location for at least a month prior to production next winter, and possibly fly out my DP for a weekend some time before we shoot.

I am however going there now in great part for location scouting... my main concern however in my interiors. A healthy chunk of the movie takes place inside a cabin and I want to make sure I will be able to get the camera in there and gauge if the 18, 25, 35, 50, 85 combo would work on Red One's 4k sensor area. I'll probably just go out there with my HVX set to full wide and make the conversion to see what that would equal on the R1.... then let my DP or other trained eyes tell me if it will feel too confined. I am going to check out two cabins, and I am hoping that at least one of those will have a big enough living room. If only I could get a viewfinder and rent the lenses for a day or two. Or maybe the best bet would be to get a DSLR with a 1.5 crop factor and that should be quite close... use that with a zoom that goes down to 18mm.

What exactly is Red One's crop factor?

[Etienne Caron]

speaking of low light shoot with Red. Ive mention that you could see some details in the shadow through the LCD, but those information dont follow when you watch the footage into RedAlert.

Roughly, its off about 1/2 stop under expose. Anyone experience that ?

For low light, i always set the temperature around 4200K, ASA 500, shutter speed at 1/24th. Crush the black a little bit in post to get rid of the noise. Bring back to 3,200K with the DPX at the end.

Dont like open up lens, with the dof chart set to CoC 1/2000 inch, you always end with out of focus shoot at f1.4. Prefer having the iris to f2.0 and have couple of inch more for focus.

Focus is so tricky with the Red, wandering if shooting with lens open at f1.3 make sens ?! Better bring some more lights...

[donatello b]

IMO ... do not shoot 2k exterior nights ( 3k , yes ) unless you want that look ...
from my experience - shoot 4k exterior night between iso 640 -1000 for a blu ray release ... i have found that 4k at iso 800 and then taken down to 2k has less noise then 2k at iso 400...
do some test at 4k , 3k , 2k at iso's between 640 -1000 ( you might throw in a iso 1600 ) and post out to blu ray ...

[Roberto Lequeux]

I wish I could but I don't own a red, we will be renting. I may be able to ask my rental house to whip that up for me but more likely that they wouldn't of course...

Let me see if I understand, shooting RAW does it matter what ISO you set the sensor to?

ISO800 at f2.0 180 would be phenomenal... I suppose we'd get a big chunk of snow lit up... I wonder how many 1.2 pars could run off a 2000W Honda quiet genny to set those up deep in the BG? Then run as many as possible of the 5000W for the main stage area and get some of the foreground lit with tungsten as spill from the cabin's lights. There would also be a tungsten practical augmented by at least a 1k or 2k right over the cast. I am sorry I realize this sort of detail is useless over a thread...

Etienne, funny thing is that I was thinking about motion blur for this scene... but I will also need a few shots without... 1/24th just might be something we can afford to do without any worries. Perhaps 1/30th, certainly 1/48th... and those shots without motion blur should be easy to do with all of out lights since they are facing the cabins which really cut the amount of BG we would see.

I have no problem with crushing the crap out of the blacks... I come from shooting on an HVX I am sure I'll get phenomenal results in comparison any way I shoot it. :) If I can get my histogram filled up from 0 to 255 I'll be happy. Shooting at night with the HVX we often didn't have enough light to be able to do that without insane amounts of unrealistic contrast...

So I guess everyone agrees that at least ISO500 4k for blu-ray is safe, and possibly higher. I guess I totally forgot about the benefits of down conversion regarding noise.

So I am set on not shooting 2k, I guess the case is closed about that and I am going to shoot with the full sensor. But I'd love to hear more about this subject from you guys, the more I can learn the better. Anyone remember of any threads or have some of their own stuff specifically shot at higher ISOs in lower than ideal light?

[Conrad Hunziker]

Let me see if I understand, shooting RAW does it matter what ISO you set the sensor to?

When recording raw, the only things that matter are the things physically in front of the sensor - the lens, iris, focus, filters, etc. Those things are baked in. The rest doesnt matter, because it can be changed. For example, say you decide to shoot at iso 500, but in post you decide you like it darker. You can "change" the iso you shot at to 400 or 320. Of course, it is not going to change the depth of field recorded or the f-stop, but it will change the relative exposure.



ISO800 at f2.0 180 would be phenomenal... I suppose we'd get a big chunk of snow lit up... I wonder how many 1.2 pars could run off a 2000W Honda quiet genny to set those up deep in the BG? Then run as many as possible of the 5000W for the main stage area and get some of the foreground lit with tungsten as spill from the cabin's lights. There would also be a tungsten practical augmented by at least a 1k or 2k right over the cast. I am sorry I realize this sort of detail is useless over a thread...


You really should be talking about details like this with your cinematographer. Even if you cant bring him over, he'd know your story, script, look and other things so you can decide these items. For instance, you can only run 1 of the 1.2's off the 2000w generator. You need to remember the measurement the 1.2 is referring to. Its 1.2kw, which is equal to 1200w. Meaning that you can only use one on your 2000w generator. Also you'll need to figure in line loss if its a great distance between the generator and the light - meaning you may not be able to run the single 1.2 off the 2000w generator.



So I am set on not shooting 2k, I guess the case is closed about that and I am going to shoot with the full sensor. But I'd love to hear more about this subject from you guys, the more I can learn the better. Anyone remember of any threads or have some of their own stuff specifically shot at higher ISOs in lower than ideal light?

Ive done a bunch of testing and shot a bunch of low-light stuff, and Im sure lots of others on the board have here also. But you need to do your own testing, with the tools you plan to use. Its too subjective and there too many variables to say that this way is crap is this way is not.

[Roberto Lequeux]

Yes, I see. I just hope that by the grace of whatever you'd like to call grace upon, that we get the full budget I am hoping for. Said number would get me a used Red package that we'd later sell... the loss would just about equal the rental I suppose, and a R1 is in no way a bad thing to own, now or ever thanks to the credit towards X. I suppose a set of Supers would not only be hard to come by but also too much of an additional expense... this has me wondering if the R1 package purchase would be a good idea... it will probably never get to that point anywHHHay... :humble:

Thanks for clarifying that tidbit about Raw Conrad... it is a good time to be shooting, and I am thrilled to hear that ISO1600 is even considerable... a clean ISO800 180 1080p would be a spectacular thing to have for a 60% tungsten 1 ton truck shoot like ours. Thank goodnes I wrote this for the snow... of course when my testicles go numb I'll probably come back and edit this post.

I wonder if a second 5000w genny rental will be in order for that night scene. I wonder if there are any other quiet hondas to be had in the Fargo area? There sure are several Reds up there.

BTW... would you say that a 1.5 crop factor DSLR is close enough for R1 scouting?

PS: You guys are phenomenal, I thank all of you from the bottom of my heart for all of the help I've been getting on this and other Reduser threads. I don't know how people survived before the www... oh, wait... I AM that old... we did just fine. :)