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S8 Booster
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..tnx for reminding me Michael Lehnert.... or Santo or.... cinematography.com super8 - the forum of Rednex, Wannabees and Pretenders...
As I am no professional and probably have far less experience than most of you, you can choose to disregard this. But What I'm thinking is, there is no such thing as a perfect exposue. Not when we are talking about the whole frame. Most of it is under or overexposed and just a small portion of it is dead on. Therefor what one has to do is to choose what area of the frame one wants to expose correctly. I don't have a handheld lightmeter and always use the internal meter. But I examine the entire frame, zooming in and checking the f-stop of different areas. Then I decide what i want perfectly exposed and see if I can get a perfect exosure without over or underexposing other areas of the image too much. Most of the time you have to make compromises. At least that is what I've discovered, and this method gives me pretty good results every time.
I also have to say that I think it's a source to misunderstanding when you talk about overexposing snow by one or half a f-stop. I say this because you are really not overexposing the snow. You are compensating for the error of the light meter. Yemi was saying a bit about this. When you overexpose as you say, you are actually trying to expose it correctly. If you were to spot meter a grey card on the snow you would get the correct exposure of the snow (probably 1 stop different from metering the snow). But the rest of the image wouldn't be correctly exposed, so again, It's a compromise.
I also have to say that I think it's a source to misunderstanding when you talk about overexposing snow by one or half a f-stop. I say this because you are really not overexposing the snow. You are compensating for the error of the light meter. Yemi was saying a bit about this. When you overexpose as you say, you are actually trying to expose it correctly. If you were to spot meter a grey card on the snow you would get the correct exposure of the snow (probably 1 stop different from metering the snow). But the rest of the image wouldn't be correctly exposed, so again, It's a compromise.
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Lucas Lightfeat
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Hi Rhcvatni,
That's a very interesting name you've got there Rhcvatni, and an excellent understanding of the practicalities of cinematography. I think we were all saying the same thing, with the same understanding of the problem, but it was coming out differently.
Anyway, you are right, it's not overexposing, but compensating for the meter's error in aiming for 18percent. This is why I try and use a grey card whenever doing something critical, though it is, like anything not built into the camera, cumbersome when shooting.
Lucas
That's a very interesting name you've got there Rhcvatni, and an excellent understanding of the practicalities of cinematography. I think we were all saying the same thing, with the same understanding of the problem, but it was coming out differently.
Anyway, you are right, it's not overexposing, but compensating for the meter's error in aiming for 18percent. This is why I try and use a grey card whenever doing something critical, though it is, like anything not built into the camera, cumbersome when shooting.
Lucas
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Yemi
The Beaulieu 4008 series does NOT have a 180 shutter angle. In fact the term 'angle' isn't appropriate since the Beaulieu has a guillotine shutter which has a speed of ~1/85 sec at 24fps. Check your manual.
Most of the Nizo 's-series' cameras (non-XL) including the Professional have a 150 degree shutter. This gives you a shutter speed of ~1/57 sec at 24fps. If you use a hand-held meter you must factor in light lost to the prism. The shutter speed values listed in most camera manuals do not account for this light loss since they expect you to use the in-camera metering.
Bolex H8 and H16 users often use the term 'effective shutter speed' when accounting for this light loss. The bolex rotating shutter has a speed of ~1/65 secs at 24fps but the 'effective shutter speed' is around 1/90 sec.
Shralp, I still think you should be able to get good results if your in-camera meter is working correctly. The Professional is a top camera.
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Yemi
Most of the Nizo 's-series' cameras (non-XL) including the Professional have a 150 degree shutter. This gives you a shutter speed of ~1/57 sec at 24fps. If you use a hand-held meter you must factor in light lost to the prism. The shutter speed values listed in most camera manuals do not account for this light loss since they expect you to use the in-camera metering.
Bolex H8 and H16 users often use the term 'effective shutter speed' when accounting for this light loss. The bolex rotating shutter has a speed of ~1/65 secs at 24fps but the 'effective shutter speed' is around 1/90 sec.
Shralp, I still think you should be able to get good results if your in-camera meter is working correctly. The Professional is a top camera.
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Yemi
To georges,
Beaulieu camera does not have rotary shutter but have develloped ( don't know why ) there how shutter system : the guillotin. So you cannot say it ... degrees but can compare it. 4008 is on 24fps 1/87s & on 25fps 1/84s so in comparasion with rotary shutter makes 100°. With a 5008, 6008, 7008 & 9008, you get in comparaison too 144°, witch is more acceptable for shooting.
Getting good exposure on super8 is not something easy because of 2 facts.First, All cameras ( except beaulieu ) got a prim based viewfinder . The prism "eats" an among of light witch is not indicated by the constructor. Secondly, the stops marked on the lens ( except 1,2/6-80 & 1,2/6-90 angenieux ) are F-stop marked, not T-stop. I guess the only solution in oder to know the among of light eaten by those two things would be to print a 18% grey card, bracket, & find out with the densitometer witch setting give you really 18%.
Beaulieu camera does not have rotary shutter but have develloped ( don't know why ) there how shutter system : the guillotin. So you cannot say it ... degrees but can compare it. 4008 is on 24fps 1/87s & on 25fps 1/84s so in comparasion with rotary shutter makes 100°. With a 5008, 6008, 7008 & 9008, you get in comparaison too 144°, witch is more acceptable for shooting.
Getting good exposure on super8 is not something easy because of 2 facts.First, All cameras ( except beaulieu ) got a prim based viewfinder . The prism "eats" an among of light witch is not indicated by the constructor. Secondly, the stops marked on the lens ( except 1,2/6-80 & 1,2/6-90 angenieux ) are F-stop marked, not T-stop. I guess the only solution in oder to know the among of light eaten by those two things would be to print a 18% grey card, bracket, & find out with the densitometer witch setting give you really 18%.
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Lucas Lightfeat
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I've been giving a lot of thought to this subject and I have some conclusions to offer, based on my Nizo 6080:
I am told that the 6080, like the 4080 etc. has a shutter angle of 220 deg.
The calculation 220/360 x 1/25 is not correct because of the prism, but the actual, or effective shutter angle, with prism taken into account, is published in the manual for the camera, so the effective angle is 202.5 degs instead of the actual 220 degs. This is really helpful, as I now know to set my light meter for 1/44.4 of a second when shooting at 25fps. From the manual:
Nizo 4056, 4080, 6056 and 6080 Exposure times:
(who cares about shutter angle - this is what we really need to know)
54 fps - 1/96 second exposure.
25 fps - 1/44.4 second exposure.
24 fps - 1/42.7 second exposure.
18 fps - 1/32 sec. exp.
16 2/3 fps - 1/29.6 sec. exp.
9 fps - 1/16 sec. exp.
I still don't quite know which light-meter to trust though - must do tests!!!
Lucas
I am told that the 6080, like the 4080 etc. has a shutter angle of 220 deg.
The calculation 220/360 x 1/25 is not correct because of the prism, but the actual, or effective shutter angle, with prism taken into account, is published in the manual for the camera, so the effective angle is 202.5 degs instead of the actual 220 degs. This is really helpful, as I now know to set my light meter for 1/44.4 of a second when shooting at 25fps. From the manual:
Nizo 4056, 4080, 6056 and 6080 Exposure times:
(who cares about shutter angle - this is what we really need to know)
54 fps - 1/96 second exposure.
25 fps - 1/44.4 second exposure.
24 fps - 1/42.7 second exposure.
18 fps - 1/32 sec. exp.
16 2/3 fps - 1/29.6 sec. exp.
9 fps - 1/16 sec. exp.
I still don't quite know which light-meter to trust though - must do tests!!!
Lucas
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Henderson
How about...
Okay, so now I've bought a light meter and my Nizo 6080 should be arriving next week. I never even thought that the Nizo's 24fps was not at 1/50 of a shutter. However, couldn't I devise a formula on the hand-held light meter where I compensate for the difference between 1/50 and 1/42.7 within the ASA punched in to the meter?
Vow, lot´s of topics criss-crossing here!
I´ll try to keep focused.
1) Yes, the Beaulieu camera has a gulliotine shutter, which makes speaking of "degrees" rather virtual. But the numbers from super8boosters list is the ones I´ve been using for calculating my exposure when shooting, and it´ve come out fine.
2) Yes, one of the most intriguing things with cÃÂnematography (whether professional or ama-teur) is that there is no "Correct" exposure, but an esthetical choice you take. When it comes to the handheld vs. TTL meter death celebrity match, I think it is always important to work on the technical level at which you feel you have the freedom to assert your creativity in what you´re doing. If you have no time to do set-ups, to really controlling your frame, if you have no assistent, or no way to manipulate the lightangels or the juice you give´em, the TTL (or other in-camera meters) might be the most convenient way of working, not having to go to and fro the camera postion and your talent. However, only working with a spotmeter, which is also rather inaccurate for being a spot-meter - it´s very impractical to always zoom in/go close to that part of the frame you want to meter all the time. This makes it difficult to really control the ratios of your picture, and ratios are pretty hardcore unforgiving in reversal film, as most super8filming is. That´s one of the reasons why I prefer my handheld meter. Another is that when you use time for set-ups, it´s also inconvenient to go around camera in hand; my lightmeter is so much lighter and practical for measuring, and I can leave my camera on the tripod. So if you´re comfortable with your in-camera lightmeter, and get nice exposures, continue doing that. Still, if you bother to find out how to aply your handhled meter readings to your s8-camera, I´m sure you will find this new tool revarding in terms of picture control. When it comes to the mentioned difference between t-stops and f-stops; (the former is the measured exposure, the latter is the mathematically assumed exposure. Almost all professional, large-gauge lenses are in t-stops) you should always to a test of your lens, and if not having an external meter to instruct the settings, in doing the test, you won´t be able to read if the resulting incorrect exposure stems from your f-stopring not being set right, or from the in-camera meter is not functioning, which you definately want to know (if possible, do as Basstruc says: "I guess the only solution in oder to know the among of light eaten by those two things would be to print a 18% grey card, bracket, & find out with the densitometer witch setting give you really 18%."). Additionally, of course, there is for the ambitious cinematographer wanna-be (like me), for whom it´s o-so-valuable to get used to the way of working of larger film productions, where in-camera metering hardly ever takes place, if not for some weird aestethic reason.
So, the best thing depends on what you´re doing and why. And, of course, you might want to use the in-camera meter as a spot-meter in certain circumstances, if you can´t afford a proper one (like me).
3)Shralp:
I´m non-accustomed to that sekonic model of yours, is it an electrical thingy? But I would think putting it in photo-mode and do as you said would work, that´s what I´ve been doing manually on my sekonic-model, but that always depends on having the right numbers; so doing a test based on the numbers you have is really the only way to really know.
Anway, good luck with your shooting!
I´ll try to keep focused.
1) Yes, the Beaulieu camera has a gulliotine shutter, which makes speaking of "degrees" rather virtual. But the numbers from super8boosters list is the ones I´ve been using for calculating my exposure when shooting, and it´ve come out fine.
2) Yes, one of the most intriguing things with cÃÂnematography (whether professional or ama-teur) is that there is no "Correct" exposure, but an esthetical choice you take. When it comes to the handheld vs. TTL meter death celebrity match, I think it is always important to work on the technical level at which you feel you have the freedom to assert your creativity in what you´re doing. If you have no time to do set-ups, to really controlling your frame, if you have no assistent, or no way to manipulate the lightangels or the juice you give´em, the TTL (or other in-camera meters) might be the most convenient way of working, not having to go to and fro the camera postion and your talent. However, only working with a spotmeter, which is also rather inaccurate for being a spot-meter - it´s very impractical to always zoom in/go close to that part of the frame you want to meter all the time. This makes it difficult to really control the ratios of your picture, and ratios are pretty hardcore unforgiving in reversal film, as most super8filming is. That´s one of the reasons why I prefer my handheld meter. Another is that when you use time for set-ups, it´s also inconvenient to go around camera in hand; my lightmeter is so much lighter and practical for measuring, and I can leave my camera on the tripod. So if you´re comfortable with your in-camera lightmeter, and get nice exposures, continue doing that. Still, if you bother to find out how to aply your handhled meter readings to your s8-camera, I´m sure you will find this new tool revarding in terms of picture control. When it comes to the mentioned difference between t-stops and f-stops; (the former is the measured exposure, the latter is the mathematically assumed exposure. Almost all professional, large-gauge lenses are in t-stops) you should always to a test of your lens, and if not having an external meter to instruct the settings, in doing the test, you won´t be able to read if the resulting incorrect exposure stems from your f-stopring not being set right, or from the in-camera meter is not functioning, which you definately want to know (if possible, do as Basstruc says: "I guess the only solution in oder to know the among of light eaten by those two things would be to print a 18% grey card, bracket, & find out with the densitometer witch setting give you really 18%."). Additionally, of course, there is for the ambitious cinematographer wanna-be (like me), for whom it´s o-so-valuable to get used to the way of working of larger film productions, where in-camera metering hardly ever takes place, if not for some weird aestethic reason.
So, the best thing depends on what you´re doing and why. And, of course, you might want to use the in-camera meter as a spot-meter in certain circumstances, if you can´t afford a proper one (like me).
3)Shralp:
I´m non-accustomed to that sekonic model of yours, is it an electrical thingy? But I would think putting it in photo-mode and do as you said would work, that´s what I´ve been doing manually on my sekonic-model, but that always depends on having the right numbers; so doing a test based on the numbers you have is really the only way to really know.
Anway, good luck with your shooting!
Istvan, I agree with everything you say. I just do the best with what I got and I guess that's what you're thinking of. As it is i've been thinking of getting a handheld lightmeter, but as I know very little about them, i do what I always do; Go for the most expensive one. i guess that's pretty stupid cause the cheaper ones probably does the trick equally well, and I can't afford the top end model anyway. Guess I'll be doing some research for the time to come.
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mattias
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true in a sense, but the asa rating is based on at which exposure medium grey registers as medium density in the emulsion when developed normally, which is what we mean by "correct exposure". there's nothing wrong in using under and over exposure for aesthetic reasons of course, but it's still under and over exposing...istvan wrote:there is no "Correct" exposure
/matt
I think we all agree on this, but i think it's a fair point when we are talking about shooting snow and snowboarders. People always talk about getting the snow right, and i think it's wrong to say that one has to overexpose the snow, because you're not. You're exposing the snow correctly.
True, and when you are exposing the snow correctly, other areas of the frame will be over and underexposed. So what's more important ; getting the snow right or the snowboarder right. Or maybe the background. Most likely you have to settle for something in between. unless the light is perfect and you get everything within a reasonable area of exposure. When you're filming snowboarding that doesn't happen often, because you can't light anything and you can't always find the perfect angle and wait for the perfect day.there's nothing wrong in using under and over exposure for aesthetic reasons of course, but it's still under and over exposing...
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Lucas Lightfeat
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Seems we've all studied cinematography - at least the basics, and this is all just semantics, as it's obvious we all know the ins and outs of exposure, at least in theory 
rhcvatni - I'm curious, did you just randomly scramble some letters into the name field when you registered for the forum, or what? It's quite funny, but I keep thinking you're Russian, which you're probably not. I also read Jerome's posts in an Indonesian accent, as it reads a bit like my Indonesian friend's speech. Jerome, I'm sorry, but to me you'll forever be an American with an Indonesian dialect!
I've just dug my old projector out, chewed up a polyester sound print, as usual, and watched some Kodachrome - so beautiful, I won't rush to use any other film on Super8, unless it's almost as cheap including processing, or I'm minted. For me, Kodachrome is like painting with oils - rich and sumptuous - better than any neg I've ever seen, which is more like acrylic - consistent but flatter, with less intrinsic character. Kodachrome - like our own little technicolour! I love it!
rhcvatni - I'm curious, did you just randomly scramble some letters into the name field when you registered for the forum, or what? It's quite funny, but I keep thinking you're Russian, which you're probably not. I also read Jerome's posts in an Indonesian accent, as it reads a bit like my Indonesian friend's speech. Jerome, I'm sorry, but to me you'll forever be an American with an Indonesian dialect!
I've just dug my old projector out, chewed up a polyester sound print, as usual, and watched some Kodachrome - so beautiful, I won't rush to use any other film on Super8, unless it's almost as cheap including processing, or I'm minted. For me, Kodachrome is like painting with oils - rich and sumptuous - better than any neg I've ever seen, which is more like acrylic - consistent but flatter, with less intrinsic character. Kodachrome - like our own little technicolour! I love it!
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focusgroup
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This is a great thread. Probably one of the most important on this web site as it deals with the true craft of filmmaking - correct exposure.
I think we're lucky in one particular way. There are relatively few film stocks available so it allows us to perfect our understanding of the available stock. As a matter fact it would seem to be great if we had seperate forum areas to discuss the ins and outs of particular stock ie vision forum, K-40 forum, Ektachrome etc. (maybe that idea is overkill).
The analogy of oil paint, Lucas, is interesting. I however may have a slightly different perspective on the analogy.
I am primarily an oil painter but have often worked in acrylic, water color, ink, and etching.
Oil as a medium ( like K-40) is extremely flexible. Yes it can be rich and lustrous if glazed, but may also be mat and flat when painted alla prima. It can be thick with impasto build up or very thin, with a wash type look similar to watercolor. I have personally seen painters who are masters of acrylic, that can glaze and create a color depth that is every bit as full as oil. The mastery depends on the artist.
The point being you have to truly master the medium to take full advantage of its properties. I decided I would only shoot with K-40 until I know what it can do. Similar to my evolving understanding of what oil paint is capable of.
Anyhow a great thread. It's great to see the finer points discussed.
George
I think we're lucky in one particular way. There are relatively few film stocks available so it allows us to perfect our understanding of the available stock. As a matter fact it would seem to be great if we had seperate forum areas to discuss the ins and outs of particular stock ie vision forum, K-40 forum, Ektachrome etc. (maybe that idea is overkill).
The analogy of oil paint, Lucas, is interesting. I however may have a slightly different perspective on the analogy.
I am primarily an oil painter but have often worked in acrylic, water color, ink, and etching.
Oil as a medium ( like K-40) is extremely flexible. Yes it can be rich and lustrous if glazed, but may also be mat and flat when painted alla prima. It can be thick with impasto build up or very thin, with a wash type look similar to watercolor. I have personally seen painters who are masters of acrylic, that can glaze and create a color depth that is every bit as full as oil. The mastery depends on the artist.
The point being you have to truly master the medium to take full advantage of its properties. I decided I would only shoot with K-40 until I know what it can do. Similar to my evolving understanding of what oil paint is capable of.
Anyhow a great thread. It's great to see the finer points discussed.
George
Hehe! No I'm not russian. And i didn't randomly scramble some letter into the name field. It was actually supposed to be RHC Vatni, where RHC is something I'm the member of, and Vatni is another version of my last name(a made up version). Don't know why it turned out the way it did, but I'm glad you enjoy it.Lucas Lightfeat wrote:
rhcvatni - I'm curious, did you just randomly scramble some letters into the name field when you registered for the forum, or what? It's quite funny, but I keep thinking you're Russian, which you're probably not.
