Stealth3kpl Posted January 7, 2011 Share #1 Posted January 7, 2011 Advertisement (gone after registration) I think I've been doing it wrong. I was reading about taking incident light readings last night and I didn't realise that 1) I'm supposed to point the cone towards the camera 2) Incident light meters are geared more towards exposing with slide film. So I got to thinking that I ought to be doing something different for exposing colour negative film. At present it seems that I'm rating my film one stop lower (eg 400 rated at 200) but because the light meter is gearing the exposure towards the highlights, I'm effectively rating the film back at box speed(?). How should I modify my metering? I suspect I could do worse than blow a film of colour neg with various exposures of the same scene to see what exposure give me what I'm looking for. Is there a method for exposing for dark/mid tones with an incident meter or should I look at complicating my life with a spot meter? Any tips appreciated (try not to mention the zone system:D). Pete Quote Link to post Share on other sites More sharing options...
Advertisement Posted January 7, 2011 Posted January 7, 2011 Hi Stealth3kpl, Take a look here Incident Light metering. I'm sure you'll find what you were looking for!
tgray Posted January 7, 2011 Share #2 Posted January 7, 2011 You are making it harder than it needs to be. Set you meter to whatever ISO you want to rate your film at. Box speed should be fine, but if you choose to give your negative an extra stop of exposure, that's your call - it should be able to handle it fine. Point the dome towards the camera while holding the meter in the light that your subject is in. Click the button. Transfer the settings to your camera. Take your picture. Clearly, if you are taking a picture of, say, someone sitting in the shade of a tree on a sunny day, you need to hold the meter in the shade as well. There's nothing about incident meters that are geared more towards slide or negative film, etc. They don't bias for the highlights or shadows. They give you the exposure to make sure an 18% gray card would come out as such on your film (more or less). 1 Quote Link to post Share on other sites More sharing options...
jplomley Posted January 7, 2011 Share #3 Posted January 7, 2011 An incident meter reading needs to be interpreted a bit differently than a spot meter. To hold detail in white, you stop down 1-stop from the meter reading. To hold shadow detail, open up one stop. In the case of the spot meter, you would open up at least two stops for white (when metering off of white) and close down 1.0 - 1.5 stops for black (when metering off of black). Quote Link to post Share on other sites More sharing options...
Stealth3kpl Posted January 7, 2011 Author Share #4 Posted January 7, 2011 (edited) Ah, yes, thanks chaps. I think subconciously I've been doing it right (but not pointing the dome to the camera perhaps). I've been setting 200iso for 400iso then taking a general reading for a general scene, or holding it up to my wife's face if that's the subject. If there was something in the scene I couldn't approach to hold the meter up to I'd take a rough guestimate on compensating eg opening up a stop for zone three. Panic over. Thanks. Pete Edited January 7, 2011 by Stealth3kpl Quote Link to post Share on other sites More sharing options...
Xmas Posted January 7, 2011 Share #5 Posted January 7, 2011 Hi The pro cine people would have stuck the meter against the actresses nose to measure the light falling on the nose, but when doing street shooting it is simplest measuring the light falling on the back of own head if you and the subject have the same illumination source, e.g both in open to sky/sun. Point the merer over shoulder. Simplistically the incident meter reading should be the same as a reflected light meatering of an average sceane. Slight of hand here, both the incident and the average reflected assume an average subject, (as a readng of a grey card does as well). This average subject is a resonable assmption most of the time unless you have a sums thought process I'd stick with it. Otherwise you have to think, or failing that use a Weston with or without the scale in link... http://www.jollinger.com/photo/cam-coll/manuals/meters/Weston_R9_Zone_Dial.pdf Do you want it simple - average metering or complicated = zones? I'm expecting a flame war saying you cant use the Zone system with 36 esposures, you can, and no returns, you dont need to alter dev, you are only getting the exposure nearer 'correct'. Note there is a 1.25 stop over exposure in normal mono ISO speed ratings, used to be 2.5 stops... pre 1961. Noel 1 Quote Link to post Share on other sites More sharing options...
Michael Geschlecht Posted January 8, 2011 Share #6 Posted January 8, 2011 (edited) Hello Pete, Some people have trouble w/ incident metering because it is so easy. Problems also sometimes arise from proceeding as if it were a variety of reflected light metering technique. It is not. Incident metering is not concerned w/ what you are photographing. The assumption is you want to reproduce the scene w/ the hi lites bright & the shadows darker w/ middle tones in the middle. You can actually measure the scene w/ the subject in another room bring the subject into the picture after metering & then take an appropriately exposed photo. What you are doing is measuring the light falling on a subject not the subject or the background. You might try an experiment: Put your camera on a tripod. Put a chair an appropriate distance away to produce a pleasant picture of yourself. Adjust the lighting. Sit in the chair & look @ the meter dial. Turn the sensor hemisphere to the camera leaving the dial where you were looking @ it. Depress the button. Look @ your correct exposure. If there is a strong main light somewhere near the camera you might want to take a second reading & photo pointing the hemisphere between the main light & the camera. Later compare the 2 photos & choose the one you like better. Most slide films I would meter @ their rated ISO. Most negative films, not Ektar, @ ISO/2 or ISO X 3/5. Ektar I would meter like a slide film. Normal development all. This actual ISO is read by the sensors in cameras scanning those little black & white boxes on the film cartridge which also tell you # of frames & ISO written on the outside of the box. It is decipherable w/ a simple decoder. Unfortunately I am too much of a computer neophyte to put a copy of one on this thread. Hope this is helpful. It really is easy. Once again: Walk up to the subject or stand in the same light. Face to or in the direction subject to camera. Look @ the meter dial. Turn the hemispherical sensor in the direction of the camera from the position of the subject. Push the button. Look @ your reading. You are done. Best Regards, Michael Edited January 8, 2011 by Michael Geschlecht 1 1 Quote Link to post Share on other sites More sharing options...
earleygallery Posted January 8, 2011 Share #7 Posted January 8, 2011 Advertisement (gone after registration) ??? you don't point the meter towards the camera, you point it towards the light source, i.e. outside you point it to the sun. It's really very simple, you may still like to bracket but you don't need to worry about negative film as it has far more latitude than slide film. Quote Link to post Share on other sites More sharing options...
andybarton Posted January 8, 2011 Share #8 Posted January 8, 2011 Agreed. The dome MUST point towards the light, not the subject. That's the whole point. Quote Link to post Share on other sites More sharing options...
pop Posted January 8, 2011 Share #9 Posted January 8, 2011 you point it towards the light source, i.e. outside you point it to the sun. Agreed. The dome MUST point towards the light, not the subject. That's the whole point. My sources say that you point the meter from the subject in the direction of the camera. That way you measure the light which falls on the visible side of your subject. Pointing to the light source would be futile if there was a large angle between light source and camera as seen from the subject. It would be vastly inaccurate if there was any amount of light reflected from the environment. Lastly, it would be impractical if there were several light sources. That's the reason it's a dome and not a tube: to catch the light as similarly as possible as does the subject. Quote Link to post Share on other sites More sharing options...
andybarton Posted January 8, 2011 Share #10 Posted January 8, 2011 Works for me. With slides. You need to measure the light falling on the subject. That doesn't necessarily come from the camera. Quote Link to post Share on other sites More sharing options...
earleygallery Posted January 8, 2011 Share #11 Posted January 8, 2011 Incident light reading - SWPP Of course you meter the light falling on the subject from the direction of the camera, i.e. you wouldn't meter from behind your subject, but essentially you are metering from the point of the subject towards the light source. If I'm out and about doing general photography/street photography, and it's not practical to meter from the subject, I just point the meter skywards. 2 Quote Link to post Share on other sites More sharing options...
StS Posted January 8, 2011 Share #12 Posted January 8, 2011 I would assume it doesn't make much of a difference, as long the matte white calotte is in front of the sensor, which should collect the light from a dihedral angle of almost 180° (and reduces the intensity to about 18% or zone 5). Stefan Quote Link to post Share on other sites More sharing options...
andybarton Posted January 8, 2011 Share #13 Posted January 8, 2011 Incident light metering obviously doesn't work if the subject is contre-jour. Quote Link to post Share on other sites More sharing options...
plasticman Posted January 8, 2011 Share #14 Posted January 8, 2011 Hmmm - I'm definitely no expert as I only bought and used a lightmeter for the first time a couple month's ago - but I assumed that the dome was designed to capture the general light falling on a subject when used for incident readings, and that it's therefore correct to point the meter in the general direction of the camera. One of the things I did was test this with the M8, and I was really surprised (unaccountably) that the exposures were perfect, even on highly reflective subjects. This is what Wikipedia says: "...incident-light meters which measure the amount of light falling on the subject using an integrating sphere (usually, a translucent hemispherical plastic dome is used to approximate this) placed on top of the light sensor. Because the incident-light reading is independent of the subject's reflectance, it is less likely to lead to incorrect exposures for subjects with unusual average reflectance. Taking an incident-light reading requires placing the meter at the subject's position and pointing it in the general direction of the camera, something not always achievable in practice, e.g., in landscape photography where the subject distance approaches infinity...." Incidentally, that last sentence strikes me as strange, as the photographer is surely most often standing in roughly the same light conditions as her/his subject in landscape photography, and therefore should be able to simply hold the meter up towards the camera to get a pretty accurate reading? I haven't yet tested this myself. Quote Link to post Share on other sites More sharing options...
pop Posted January 8, 2011 Share #15 Posted January 8, 2011 Incident light metering works even in contre-jour shooting, but does not give the desired result as it would expose for the dark side of the object facing the camera. Yes, I know that this sounds like hair-splitting, but I think it is important to be accurate in this kind of discussion. It's different in the field, I hope. Where incident light metering can not work is when the subject is emitting or passing light. Quote Link to post Share on other sites More sharing options...
plasticman Posted January 8, 2011 Share #16 Posted January 8, 2011 (edited) Incident light metering obviously doesn't work if the subject is contre-jour. Isn't that the very point - it surely would work if you point the meter towards the camera? (1) seems like Philipp beat me to it (2) the Sekonic 380s has a sliding dome, so you can just slide it away, point the meter at the subject (if it's emitting light), and take a spot reading (3) please bear in mind I barely know what I'm talking about here - but I LOVE the liberation and knowledge that's coming with using a lightmeter. It's increased my feel for exposure and light a thousandfold in these last two months. EVERYONE should get one! (4) final extra edit - I forgot that by 'contre jour' you meant silhouetted against the light. So no, it wouldn't work in that way. But then if that's what a photographer was trying to achieve, I guess they'd work it out for themselves... Edited January 8, 2011 by plasticman 1 Quote Link to post Share on other sites More sharing options...
tgray Posted January 8, 2011 Share #17 Posted January 8, 2011 Gotta agree with the last two posts. I use incident metering with backlight subjects all the time. In that case, you don't aim the meter towards the light source, unless of course you wanted to meter for that light and you don't care if your subject is potentially underexposed. You aim it towards the camera. Quote Link to post Share on other sites More sharing options...
pico Posted January 9, 2011 Share #18 Posted January 9, 2011 (edited) ??? you don't point the meter towards the camera, you point it towards the light source, i.e. outside you point it to the sun. . Perhaps there is some kind of quoting problem here, but for incident readings you stand at the subject (or an ideal similar position) and point the meter toward the camera. How simple can it be? You do not point it to the sun unless that coincides with the subject-camera vector. Of course this presumes you have an incident-reading dome on the meter. Edited January 9, 2011 by pico 1 Quote Link to post Share on other sites More sharing options...
earleygallery Posted January 9, 2011 Share #19 Posted January 9, 2011 (edited) I was taught that the point of an incident reading is to measure the light falling on the subject, ideally from the point of the subject, as opposed to reflected readings which is the light reflected off the subject. In most circumstances the light source will be behind the camera or at least in the general direction of the camera so that advice isn't incorrect as such, however there can be circumstances where failing to meter the light source will result in an incorrect exposure..... Suppose a person is standing facing towards the light source, lets say the afternoon sun. If you wanted to photograph them from the ground looking up, if you pointed your meter to the camera you would most probably end up with incorrect exposure. Hold the meter by the subject pointing to the light source = correct exposure. In a contre jour scenario, a spot meter would be my choice, or a very close up reflected reading. Edited January 9, 2011 by earleygallery 1 Quote Link to post Share on other sites More sharing options...
pico Posted January 9, 2011 Share #20 Posted January 9, 2011 (edited) Suppose a person is standing facing towards the light source, lets say the afternoon sun. If you wanted to photograph them from the ground looking up [...] Interesting point. Not many of us shoot from ground-level to a nearby subject above us, but knock yourself out. The difference will be minimal. I stand by what I wrote. Edited January 9, 2011 by pico Quote Link to post Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.