I have been asked a few times how to meter the Canon DSLRs camera when using Contax Carl Zeiss and Leica R Lens. Please look at the histogram when you set up the metering.
Brief Description of Manual Metering:
The conveniency of digital camera has allow most of us to use less of an independent meter.
This is my procedure of how to get the best exposure to maximize the resolving power of these Zeiss and Leica Lens and the size of the digital sensor. I will describe my technique and simplify it so everyone can follow:
A) Aperature Priority Mode:
1) Remember the F stops of your Zeiss and Leica Lens so when you focus your subject at wide open aperature, which facilitate your focusing due to the brightness of the screen. You can count how many click it takes to go from say f/2.8 to f/5.6 and so on. you can stop down to the aperature you want while you are still looking at the subject through the view finder.
2) Once you finished your composition and focus at wide open aperature you now place your hand onto the aperature ring and turn the number of click to get to your f stop desire while you are still looking through the view finder.
3) Gently press the button to allow your camera to do the meter for you.
4) Completely press the button to take your picture.
*****Note1*****
Please look at the histogram for the first image you take in the scene of your interest. The histogram allows you to properly determine if you are in good exposure. Make sure that both ends of the histogram is not cut off. Eventually, you will learn that this is not the case for certain image that you are interest to make. For example, when you taking a picture of high contrast and low light effect you may have the left side cut off. But once you keep your attention to the proper metering for good exposure you will maximize your lens and image sensor resolve power.
*****Note2*****
Every camera metering is different and since the Zeiss and Leica Lens cannot communicate with the camera you need to do your own test to see whether your camera has the tendency to under expose or over expose your image. From my experience most camera under expose your image by 1 to 2 f stops. Thus, you need to compensate your metering tendency by increase your exposure by 1 to 2 f stop depending on your finding of your camera. This is what makes you a pro versus a non pro; it is your ability to manually correct your camera meter's inaccuracy. Even if you have the Canon Lens on it the aperature priority still under or over expose your image from time to time due to the Reflective Metering System (RMS) that is built into your camera.
B) Manual Metering Mode:
1) Use the aperature mode describe above to sample the rough estimation of the speed you need for the f stop you are going to take your image with.
2) Switch to the manual metering mode of shooting and increase the shutter speed by one or two stop if your image is overexpose or decrease your shutter speed by one or two clicks if your exposure is underexpose.
*****Note3*****
I like to use the manual mode once I determine the light condition of the scene that I am interested by using the aperature priority mode and then make the right adjustment in the manual mode. Once I set up the manual metering mode I just take pictures and the image will be properly expose.
If the scene keep changing light such as a sunny day with clouds floating then I would make a mental note of the sun is out of the cloud or when the sun is in the cloud and make my metering adjustment in the manual mode and it give me proper exposure.
Edited by PhotoCinematic on Mar 25, 2005 at 01:39 PM GMT
Spartan123, thank you I took this time and hope it will help our FM members especially now alot of folks are getting a Zeiss or Leica R lens to work with their digital SLRs.
The evaluative metering system is the easiest and best for most of our user here. I think as they progress they will be able to use the spot metering more effectively. If I was going to use the spot mode I would then do it with a mind thought of Zone metering.
Yes, indeed, it is very nice of you to clarify the metering aspect when using non-Canon lenses. I have been using the aperture priority mode with a high rate of success. I would say the exposure was right on the money in about 90%. If not, it tends to underexpose by 1-2 stops. Again, this has been my experience.
I also like the idea of remembering the clicks when closing the aperture. I have two non-Canon wide angle lenses; a 28mm CZ Distagon with full-stop clicks and the 19mm Elmarit with 1/2-stop clicks. So, I got to remember, which is which . But I have been using the hyperfocal focusing method for landscape so I have to look at the depth of field scale on each lens and focus accordingly.
Thank you for the detailed report.
My own and few other FMers' experience is that Av mode, described in A) 3) step above, doesn't work as expected. With D30, only the center-weighted partial metering mode kind of works but not reliable. You can do the experiment easily. Just aim the camera at the blank wall in Av mode. From Aperture wide open, click it down one stop at a time and see if the shutter speed follows with one stop step. It doesn't ! The metering works at the wide open aperture. And the error becomes larger at smaller apertures.
My theory is that it has something to do with the fact that EF system "calculate" what the metering would be without actually closing down the aperture to the actual size. And the calculation with multiple sensors works only with EF lens. It may have something to do with right fall-off as you move toward the outside. I'm not sure....
Pondria,
If you aim at the blank wall the Reflective Metering System (RMS) will give you error in the reading since the wall may be too bright and thus give you the underexposure. If you aim at the wall you will definitely gets the underexposure and not overexposure. Thus when using a RMS you are required to manually compensate your own exposure unless your scene is 18% gray scale (I know there is an arguement on this grey scale stuff with digital too but it is not the goal of this thread). Ambient Metering System will be very effective for us but less people are going to use this independent metering device since digital camera with histogram give us the chance to see our exposure and compensate our exposure.
Yes, I agree that Canon has built their RMS in the camera with requirement of the information coming from EF lens to compensate the RMS for proper exposure. This information has been posted by Pondria before and for those that are interested in this information should read more on it. Pondria is one of the leading FM members here and his experience and thoughts are held in high regards.
My hope that as we are comfortable with manually compensate the RMS in our Digital SLR we will get the proper exposure. In general the scene of your interest will be properly exposed once you make the necessary adjustment as described in the original post. You can view your image with the histogram from time to time as you think the light condition has change in your scene otherwise you are in great exposure.
I hope that we use theory and information that is presented and we should apply it to our shooting and make it works for us. Nothing is simple in the quest of attaining high image quality. It will based on our experience and our ability to adapt in whatever the condition or equipment availability present to us. Just make it works in our applications and don't just let theory scare us of our goal. Theory allows us to make better judgement as we adapt to the challenge and help us solve the problem.
Son,
So, what I think would be neat is a new mode, say, "Fixed Ev".
It works like this. Say, you find that f/2.8 and 1/125sec are the right metering. And you don't want to be bothered by Av or Tv. So go to manual mode and set it at 2.8 and 1/125. Now, you want to change either one of aperture and Shutter speed. And you still want the exposure to be the same. In other words, you shift aperture to f/4, then the shutter speed would change to 1/60.
Pondria,
As I mentioned earlier your thoughts are held in high regards. I think we should tell Canon to give us the "Fixed EV Mode". I am not sure if you ever use a Hasselblad Carl Zeiss Lens. But this actually is the case where you press down the button and make your aperature change and the shutter also change accordingly so that your exposure is unchanged. However, these Hasselblad lens have a built in leaf shutter and thus they facilitate this process.
Guy,
Great point about the AV mode with the thumb dial to adjust exposure compensation. The metering is a lot easier than most people make it out to be.
Thank you for all the input on metering. I have tried all of the above suggestions plus a few of my own ideas. It seems like none of them are reliable and different from lens-to-lens and body-to-body .
Eventually I end up doing my own initial guess of exposure using M mode, then adjust the aperture and/or shutter speed according to the information from the histogram. This is not bad as long as the lighting does not change frequently. Sure miss the ability of coupling aperture/shutter speed as with the Hasselblad lenses. After shooting auto everything for awhile, it is tough to go back to all manual system.
I will reserve using the non-Canon lenses for still life or portrait, or for fun. Seriously, if the shooting is critical and there is no room for error, I will rely on my favorite Canon lenses.
Son,
Thanks for posting this thread. This is the technique that I arrived at myself after many errors. It is nice to have it confirmed by the guys that "know". Guy,
The thumbwheel adjustment did not occur to me and for that bit of advice, a BIG thank-you.
Pondria,
Thank you for helping me understand WHY it doesn't work the way I thought it would in AV mode. I kinda/sorta knew that stuff, but the little light in my head never went off.
David,
It is great that we all comes together and present the information to the forum especially during a time when it is needed. Guy, Pondria and yourself have been invaluable to the forum.
Stephen, that is one nice imagon lens you got there. If you ever want to part with it you know where you can drop it off. I have the Imagon 250mm for the Large Format Camera (LFC) I would like to know how do I acquire the focusing tube to make it works for my Hasselblad? Any suggestion would be great.
THere is one other trick you can do that is not mentioned here. If your lens persistently underexposes, you can use custom function 5 and select number 2 that allows you to adjust camera exposure in M or Av mode without lens. Since the mounted non canon lenses are read by the camera as being without a lens, you can adjust the baseline aperture of what the camera believes is wide open. So if your lens underexposes, you go to CF 5, #2 and set the camera aperture to something greater than 1 (e.g. 1.4, 1.8, 2,8 etc) based on how much the exposure is off and the camera-lens combo will now be calibrated. Mark
PhotoCinematic wrote:
David,
It is great that we all comes together and present the information to the forum especially during a time when it is needed. Guy, Pondria and yourself have been invaluable to the forum.
Stephen, that is one nice imagon lens you got there. If you ever want to part with it you know where you can drop it off. I have the Imagon 250mm for the Large Format Camera (LFC) I would like to know how do I acquire the focusing tube to make it works for my Hasselblad? Any suggestion would be great.
-Son
Son,
I bought the Rodenstock Imagon 200 when I was using my Hasslblad for portrait. I also bought a 2000 body so that I can use the lens without using the Copal shutter. The soft effect of the Image is amazing and only the Imagon (and Fuji I think) use the disc system to achieve the SF effect.
The kit came with the focus barrel made by Rodenstock for Hasselblad mount (also availbale for Mamiya RB67 & Rolliflex SL66 I believe). I won't be surprises that the same barrel can be used for your 250. Here is a bit more information I can found regarding the Rodenstock Image kit:
The whole kit (the 200mm lens with Copla 3 shutter, set of disc and the barrel) is LNIB, and I even have the original box and manual. I understand that Rodenstock Imagon has 3 focal length: 200, 250 & 300 mm. The 200 & 250 both have three perforated diaphragms, while the 300 has only two. From reading my manual, I think all three Imagon lenses use the same size 3 mechanical shutter. If you look around, you may be able to locate the focus barrel. If you need more information on the barrel, please let me know.
P.S. Further checking confirms the rear mount diameter of all three Imagon lenses are the same size 60 mm:
Mark wrote, "THere is one other trick you can do that is not mentioned here. If your lens persistently underexposes, you can use custom function 5 and select number 2 that allows you to adjust camera exposure in M or Av mode without lens. Since the mounted non canon lenses are read by the camera as being without a lens, you can adjust the baseline aperture of what the camera believes is wide open. So if your lens underexposes, you go to CF 5, #2 and set the camera aperture to something greater than 1 (e.g. 1.4, 1.8, 2,8 etc) based on how much the exposure is off and the camera-lens combo will now be calibrated. Mark "...Show more →
That is great information Mark. Thanks for your input into this matter.
Pondria wrote:
Son,
So, what I think would be neat is a new mode, say, "Fixed Ev".
It works like this. Say, you find that f/2.8 and 1/125sec are the right metering. And you don't want to be bothered by Av or Tv. So go to manual mode and set it at 2.8 and 1/125. Now, you want to change either one of aperture and Shutter speed. And you still want the exposure to be the same. In other words, you shift aperture to f/4, then the shutter speed would change to 1/60.
I have been crying for *smart manual mode* for a Long time my frined, Hassy cameras have this type of control on some of their bodies
John,
The Hassy Zeiss Lens give you this posibility where you first set up the EV value on the lens and then you just push the lock to move the shutter accordingly so that your EV is exactly the same.
PhotoCinematic wrote:
John,
The Hassy Zeiss Lens give you this posibility where you first set up the EV value on the lens and then you just push the lock to move the shutter accordingly so that your EV is exactly the same.
The older Hassy lens operates just the opposite way: you push the 'lock' to disengage the shutter/aperture lock in order to move the shutter or aperture independently.
. But I have been using the hyperfocal focusing method for landscape so I have to look at the depth of field scale on each lens and focus accordingly.
.