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Chris Johnston
08-04-2011, 08:30 AM
I've got a 25K budget approved for 1 Oct. Looking to get a couple more cameras for (primarily) studio work.

Also wanted one of these cams to be either a af100 or fs100 (leaning to fs100)

My question is about controlling exposure if I take it outside (florida, sunny)
This cam is apparently very sensitive so I'm wondering how to get exposure right. I've seen numerous clips where they apparently
have to turn the shutter speed way up......

If I want to shoot something at a 60 shutter speed and a wide open iris (1.4- 2.8 ish) outside is my only option something like a
Heliopan variable ND filter? Is that how everyone is controlling exposure since there's no negitive gain?
and would that particular variable ND darken it up enough to shoot something with those settings?

It doesn't seem like a bad workflow...set shutter to 60, set the iris to the setting I want, should I chose to want a shallow DOF. and then just adjust the vari ND to get the exposure right.
Hate to pop out the newbie question but I just see sooooo many posts about this, just want to make sure this is the correct/easiest way to do it.....

alaskacameradude
08-04-2011, 09:44 AM
That is EXACTLY how I do it. Shutter speed set to twice frame rate (48 for 24p 60 for 30P or 60i). Set iris to what I want. Use Heliopan to dial in correct exposure. Works just
great.

Chris Johnston
08-04-2011, 10:18 AM
Thanks AK will the heliopan darken enough to get a wide open iris? or do I have to add aditional nd? (if it's bright outside)

Alpern
08-04-2011, 12:08 PM
If you have the budget and I looks like you do. I would go with something like the Tiffen Indie Pro IRND Kit ( http://www.filmtools.com/tiffen-77mm-indie-pro-irnd-kit-w77indprokt.html (http://www.filmtools.com/tiffen-77mm-indie-pro-irnd-kit-w77indprokt.html)). You will have problems with IR Pollution if you used heavy ND with out an IR filter.

alaskacameradude
08-04-2011, 12:31 PM
Thanks AK will the heliopan darken enough to get a wide open iris? or do I have to add aditional nd? (if it's bright outside)

Well, I can't say for absolute certain as I just have the kit lens right now. I am waiting for the new Sony adaptor (rumored announcement on
August 24th) to drop before I purchase my additional lenses, just want to see what that is all about as it may change what lenses I buy.
So, my kit lens only opens to F3.5. However, when I am outside on a sunny day, at F3.5, I still have an additional 1.5 - 2 stops on the Heliopan
filter, so I think that F2.8 at least would work fine. The Heliopan is supposed to give you up to 6.6 stops of ND. If you are interested in seeing how
it performs (sharpness, color and so on) you can take a look at this link:

http://exposureroom.com/members/alaskacameradude/14d879d0c3924609974edd0388478689/

jetswing
08-04-2011, 12:42 PM
Thanks AK will the heliopan darken enough to get a wide open iris? or do I have to add aditional nd? (if it's bright outside) 6 stops isn't going to be enough for Florida midday sun -- especially at wide open.

Chris Johnston
08-04-2011, 01:46 PM
6 stops isn't going to be enough for Florida midday sun -- especially at wide open.

How would you get around that? OK to screw another (say...hard 2 or 3 stop) nd filter onto the heliopan?
I'd hate to not have DOF if I want it, just because it's sunny.

alaskacameradude
08-04-2011, 01:52 PM
The Heliopan gives you almost 7 stops. I'm not in Florida, so I don't know, but I think you would be OK at F 2.8. At F1.4 you are probably going to need more ND.
However, the Heliopan does NOT have front threads, so you can NOT add another filter to it! You might look at the new Tiffen variable ND which was introduced at
NAB. It is supposed to give you from 2-8 stops instead of 1-6.6 which is what the Heliopan does. However, both of these filters are hard to find and seem to be
out of stock quite a bit, so you will probably have to look around a bit.

Chris Johnston
08-04-2011, 03:12 PM
Anyone ever use the tiffen? I've read a few posts about about variable nd's getting soft on longer glass. (although a 85mm nikon is the longest glass I have)

DOSMedia
08-04-2011, 06:10 PM
The Heliopan gives you almost 7 stops. I'm not in Florida, so I don't know, but I think you would be OK at F 2.8. At F1.4 you are probably going to need more ND.
However, the Heliopan does NOT have front threads, so you can NOT add another filter to it! You might look at the new Tiffen variable ND which was introduced at
NAB. It is supposed to give you from 2-8 stops instead of 1-6.6 which is what the Heliopan does. However, both of these filters are hard to find and seem to be
out of stock quite a bit, so you will probably have to look around a bit.

I shot up on a glacier a few times this summer, and when I threw my ND1.2 (4 stops) in front of the lens I could stop down pretty far. At 3.5, 1/120 was fine... and thats on a glacier which is probably a stop or two brighter than Florida. I was able to shoot at 1/60 with that same ND perfectly fine last weekend in southern california mid day... at 3.5. 6.6 stops is probably safe.
I also threw on my 50 1.4, but it was raining, so thats not a fair comparison. My 80-200 f4 also worked fine obviously.

Both my 80-200 f4 and 50 1.4 were not wide open though. I was at f2 on my 50 and 5.6 on my 80-200. I like to stop down each of my lenses a slight bit when I use them to get them at their sharpest.

Keep in mind if you have never used this camera that you most likely do not need 1.4. I found F2 at 50 to be extremely shallow. Hell ive even gotten lots of shallow stuff with this camera at 5.6 below 100mm.

With all of that said though, if Tiffen does have the 2-8 stop ND, then I would say go with that to be safe. I have a Tiffen ND1.2 for my matte box and love it. Tiffen makes some quality filters, so I would not hesitate to go with them but I have not used that specific one.

Be excited for this camera! You will definitely love it! Just be prepared to want to immediately pick it up to go shoot something again once you sit down at the desk and see some of what it creates.

alaskacameradude
08-04-2011, 06:23 PM
Yeah, I have always been just fine with the Heliopan, but the kit lens only goes to f3.5. I was just guessing that since I still had a couple stops available, that it would be
ok for F2.8. However, as you said, you can get stuff that is way shallow, even with the slow kit lens.....well shallow compared to a video camera anyways. If you used a F1.4 on
it, you'd probably only be able to keep one side of someone's face in focus!

I would echo the comments about how you will just want to go shoot with this thing. It just gives you such beautiful looking stuff, it's kind of amazing to be honest.
I'm shooting some stuff for Toyota on the 8th, and this is the first time, I feel like I have a camera that can do justice to bigger budget TV spots.

TimurCivan
08-04-2011, 06:28 PM
Try traditional ND, they have less issues. NDfaders can cause some odd image quirks.

For out door work in broad daylight, you need 3x .9 ND filters to shoot at a T2:8 @ ISO800

Douglas Villalba
08-04-2011, 07:20 PM
I don't see what camera DOSmedia was using but a HDSLR ISO goes down to 100, but this camera at 0db is around 800 as TimurCivan mention above.
That is 3 more f stops.

alaskacameradude
08-04-2011, 08:31 PM
Try traditional ND, they have less issues. NDfaders can cause some odd image quirks.

For out door work in broad daylight, you need 3x .9 ND filters to shoot at a T2:8 @ ISO800

Not trying to start anything as you obviously know your stuff, but just wondering if you've used a Heliopan variable ND before?
All variable ND's are NOT equal, (that's why some cost $80-$125 and the Heliopan costs $400 plus) and the Heliopan is awfully close
to a flat ND filter in my opinion. Of course, that's just my opinion, although I do know that Philip Bloom has also said this on his
blog. However, I'm not saying I'm right, you may well have seen issues with this filter that I haven't, I don't think I tend
to work on as high end stuff as you do, so if you have used it and seen issues, I'd defer to your experience.

NeedCreative
08-05-2011, 05:13 AM
To shoot at 0db af F2.0 in bright daylight, I had to throw 9 stops of ND up there in the Matte Box. (a 1.8 and a .9 stacked - 6+3 stops). YMMV of course

Chris Johnston
08-05-2011, 06:19 AM
Thanks for all the info. It looks like the heliopan or tiffen are something I think are (almost) required to shoot with this cam. (at least for me at the beach)
I'm still a little confused about the iso/gain relationship. Is there a chart that lists the X gain = X ISO numbers anywhere?


EDIT: I plan on getting the kit glass also but have several older nikons. I don't suppose the birger mount will be available for this cam by Oct 1 which is
a bummer because I have some nice Canon glass that I wanted to use. (which was one of the main reasons the AF100 was still being considered)

TimurCivan
08-05-2011, 06:35 AM
Iso is the "actual" light sensitivity. ISO800 on a fs100 and a AF100 and 5D should be the same.

Gain is the video term for how much the camera boosts the signal from that starting ISO point. Its measured in dB. Every 6 dB is a stop worth of light.

Chris Johnston
08-05-2011, 06:49 AM
Gotcha. ISO is always 800, Gain allows you to "simulate" moving the ISO higher but since there's no negative gain, 800 is as far as you can go. (lower)

matteo1
08-05-2011, 10:34 AM
This is from Abel Cine and was specifically done for the F3, but the numbers should be similar for the FS100 which uses the same sensor (the gain / ISO information is in a chart from on the Abel Cine page):

http://blog.abelcine.com/2011/03/11/abelcine-tests-the-sony-f3-iso-rating/

"We’ve done a lot of testing with the Sony PMW-F3 camera and had great results. Our tests included sensitivity, dynamic range and low light performance. In a three part series, Mitch and I will cover all of these topics with the hopes of shedding light on what this camera can do. The F3 had the following settings for this test: 1920×1080 23.98p, Rec709 Gamma (STD5), Auto Knee OFF, Black Gamma 0, Matrix Standard, Detail OFF, Aperture OFF. All testing was performed with a Leader LV7330 scope, DSC Labs Camalign ChromaDuMonde chart, and Sekonic L-758Cine light meter. Watch the video above to see how we determined the ISO ratings of the camera at different gain levels, or keep reading below to see our results."

"Here are our results:

Gain db Level / ISO Rating

-3 db 500 ISO (FS100 doesn't have this option)

0 db 800 ISO

+3 db 1000 ISO

+6 db1600 ISO

+9 db 2000 ISO

+12 db 3200 ISO

+18 db 6400 ISO

DOSMedia
08-05-2011, 10:42 AM
I don't see what camera DOSmedia was using but a HDSLR ISO goes down to 100, but this camera at 0db is around 800 as TimurCivan mention above.
That is 3 more f stops.

yeah I know what an HDSLR does.

Obviously since I am posting in this forum and thread, I use a FS100, so I dont get what you are trying to say.

Barry_Green
08-05-2011, 10:45 AM
Depends on what gamma you are using. In the standard 709 gamma, it's 800 ISO. When you use the cinematone gammas, they render a darker image, which more corresponds with ISO 500.

DOSMedia
08-05-2011, 10:47 AM
This is from Abel Cine and was specifically done for the F3, but the numbers should be similar for the FS100 which uses the same sensor (the gain / ISO information is in a chart from on the Abel Cine page):

http://blog.abelcine.com/2011/03/11/abelcine-tests-the-sony-f3-iso-rating/

"We’ve done a lot of testing with the Sony PMW-F3 camera and had great results. Our tests included sensitivity, dynamic range and low light performance. In a three part series, Mitch and I will cover all of these topics with the hopes of shedding light on what this camera can do. The F3 had the following settings for this test: 1920×1080 23.98p, Rec709 Gamma (STD5), Auto Knee OFF, Black Gamma 0, Matrix Standard, Detail OFF, Aperture OFF. All testing was performed with a Leader LV7330 scope, DSC Labs Camalign ChromaDuMonde chart, and Sekonic L-758Cine light meter. Watch the video above to see how we determined the ISO ratings of the camera at different gain levels, or keep reading below to see our results."

"Here are our results:

Gain db Level / ISO Rating

-3 db 500 ISO (FS100 doesn't have this option)

0 db 800 ISO

+3 db 1000 ISO

+6 db1600 ISO

+9 db 2000 ISO

+12 db 3200 ISO

+18 db 6400 ISO

Interesting... this was their FS100 results,



Gain db Level
ISO Rating


0 db
500 ISO


+3 db
800 ISO


+6 db
1000 ISO


+9 db
1600 ISO


+12 db
2000 ISO


+15 db
3200 ISO


+18 db
4000 ISO


+21 db
6400 ISO


+24 db
8000 ISO


+27 db
12800 ISO


+30 db
16000 ISO



http://blog.abelcine.com/2011/05/27/sony-fs100-ratings-and-dynamic-range/

DOSMedia
08-05-2011, 10:47 AM
Depends on what gamma you are using. In the standard 709 gamma, it's 800 ISO. When you use the cinematone gammas, they render a darker image, which more corresponds with ISO 500.

THanks Barry. That makes more sense now.

trian
08-06-2011, 02:20 AM
Hello Videohog,

I've been using a FS-100 with a Heliopan filter for a few weeks now. Still waiting for the Birger mount to be released I've seattled for a dummy
adapter, that allows me to use my Canon lenses. I've been using the Canon 24-70 mm (2.8) the most. My experience with this camera (and after shooting with DSLRs for quite some time) using 1.4- 2.8 on a lens is rarely very useful. It depends what you're after. So far I've been comfortably shooting around 4 on the FS-100. If I need a more shallow DOF (using 4) is just move my camera a few steps back and zoom in with the lens. Or I use the Heliopan filter. There are more ways to control the DOF, if the space is available, of course. So far I'm very pleased with the results I get from the FS-100. And when the Birger mount is released, even more so. No camera is great for everything, but the FS-100 is definitly a valuable tool in many shooting situations.

The Heliopan filter - compared to my six Fader NDs - seems to be sharper and less prone to vignetting so far.

Cheers,
-terje

dstoe
08-06-2011, 01:33 PM
Hello Videohog,

If I need a more shallow DOF (using 4) is just move my camera a few steps back and zoom in with the lens.

This does not work. If your framing stays the same, so will the depth of field.

Barry_Green
08-06-2011, 04:18 PM
This does not work. If your framing stays the same, so will the depth of field.
Technically true. Observationally, not so. The background will be magnified more, which magnifies its out-of-focusness.

TimurCivan
08-07-2011, 01:08 AM
"out-of-focusness".

Nice.

jambredz
08-07-2011, 07:37 AM
lol

Chris Johnston
08-07-2011, 07:54 AM
"out-of-focusness".

Nice.

That's the technical term I always use.....

Chris Johnston
08-07-2011, 08:11 AM
On another note, My main concern for this purchase was to get more equipment for studio "head and shoulders" and interview type shows. (these are usually 30 minute broadcasts with occasional PSAs etc, well controlled, lighting etc).

I was planning on buying a AC-160 (if available oct 1) or another hmc150 if not. I've had great results with the 150/ Canon DSLR combo I've been using. but I'm wondering if the FS100 with function well with the kit lens in studio. I'm almost always a one man show for the studio shoots (typically 2-3 cam shoots, 1 on sticks wide, 1 on sticks zoomed on something of interest, and 1 that I move/pan/zoom as the conversation/event/show move along.)

I must admit, I'm very interested in the large sensor type cams for shorts, music vids etc, but in studio interview type stuff is my bread and butter. I'm seriously
considering 2 FS100s if they don't need a lot of monitoring/setup etc with the kit lens. (I don't imagine the slow kit lens would be a problem in this environment?)

AndyInBuffalo
08-07-2011, 12:18 PM
videohog,
Be aware that the kit lens and most long zoom still lenses are not constant aperture through the zoom.

trian
08-08-2011, 01:07 AM
"Out-of-focusness" is nicely put. Thank you Barry!


Dstoe,
My response was about the need of using a camera like the FS-100 wide open at 1.4-2.8, which I don' find very useful in most shooting situations. I might add that during shooting you should constantly be evaluating your storytelling (and editing options). If a scene for some reason needs less DOF you plan accordingly. You can move your camera back and zoom in with the lens and/or reframe to achieve less DOF or you can change the angle of shooting to increase the object to background ratio or you can change the location all together to achieve the look you're after. Using a quality vari-nd filter makes your options even greater. My point is that I don't have any problems getting a useful quality of shallow depth of field, that will support the storytelling, even using the lens open at 4 and even 5.6. That's my experience with the FS-100 and similar large sensor cameras.


Cheers,
-terje

Chris Johnston
08-08-2011, 08:23 AM
I don't really imagine that shooting with this cam (at it's sensor size) at 1.4 would be very practical in most situations. That being said, I still wanted to know that I have the ability to do that. I'm a cheapskate so when I buy something, I'd like it to do everything it should do without having to jump through flaming hoops of fire.