After clicking the shutter button, the camera body gives error 99 and the viewfinder will be very dim, on checking the aperture is shut down to a tiny hole, something like f/16 or 22, even though my setting was f/2.8 or 4. Happened many times, in different scenarios like outdoor and indoor aircon. So I ruled out temperature. I have also never dropped, abuse or rough-handled the lens. Also, the IS seem to vibrate non stop sometimes. By vibrate I mean really shake non-stop for up to 10-20 seconds. The whole viewfinder is like in an earthquake. Standard treatment of cleaning contacts was also done with no help. Anyone have the same problem and got a workaround? I'm stopping short of sending to Canon Service Centre because I don't have the time and I need my lens almost every few days.

Do you mean set the aperture at f/11?

If you want the camera to set the shutter speed for proper exposure, turn the mode dial to the A position for Aperture Priority. Press the +/- button to display the shutter speed and aperture. Press cursor-up/down to change the aperture and the camera will change the shutter speed to give the proper exposure.

If you want to set the shutter speed and aperture yourself, turn the mode dial to M for Manual. Press the +/- button. Press cursor-up/down to set the shutter speed, cursor-left/right to set the aperture.

Full details are in the Shooting Mode section of the manual.

First, the "r06" message is NOT an error code. It indicates the number of shots remaining in the internal memory buffer, before the camera must prevent additional shutter actuations so that it may transfer those images already in the buffer to the memory card. This "r" number will decrease with each shot taken in rapid succession until it reaches 0. The shutter release will no longer work until the buffer is transferred to the memory card, then shooting may continue again.

As far as not being able to even see through the viewfinder, it sounds like something may be obstructing the light from reaching the meter and viewfinder. The problem is most likely the position of mirror inside the camera body. With the lens off the body, the mirror should be plainly visible at about a 45 degree angle to the opening. A side view drawing of this is below. The solid red line is the mirror in the normal position. The red dashed line is the up position of the mirror when the shutter is released.



When the mirror is in the "normal" position, the light from the lens is projected on a screen so that the image is visible in the viewfinder for composing and can be metered. When in the "up" position (when the shutter release is fully depressed), the light from the lens is projected on the camera's sensor for as long as set by the manual settings or program; based on ISO, aperture, etc. At the end of this time, the mirror returns to the "normal" position.

If your D100's mirror is not in the lowered 45 degree angle position, the image seen in the viewfinder is inside the camera - not that which the lens would project. Hence, the dark viewfinder, long exposure times and - I'm guessing - severely overexposed pictures because way too much light is striking the sensor because the meter is only seeing darkness.

If the mirror is ok, with the lens removed from the body, look for the aperture lever as shown in the yellow circle in the picture below:



By default, the aperture is at minimum. The camera moves the lever from this position to full open (and anywhere between) as needed. You should gently move the lever to the other end of its travel to open the aperture to maximum. Point the lens away from a light source but preferably at a light colored background. Look through the lens. There should be no obstructions and be clear. Next, look at a dark colored background to find the same results. If you want, you can even allow sunlight to shine through the lens onto a sheet of paper (like a magnifying glass). The result should be a bright circle with no obstructions. Obstructions in the lens will prevent the meter in the camera from getting accurate information about the scene and if significant enough, prevent viewing through the viewfinder.

You may wish to have the camera & lens professionally cleaned and serviced to repair a mirror or lens issue.

If this was helpful, please rate it as such. Good luck!

Hi,1) Your camera has damage to the aperture control mechanism.
2) If you look in the viewfinder the image darkened, mayhave bent the aperture control lever.
In one must turn for service.
In two carefully can solve You can also check whether the mechanism malfunctions diaphragm aperture setting to full and see that this does not close completely,pressing the shutter release button.
Best regards

There is no communications between the camera and lens. When using a set up like this everything becomes manual and you must remember to stop down the aperture to your taking aperture before releasing the shutter. I don't know what camera or format you are going to use this lens with but assuming it is a digital "bridge" (a camera that is between an amateur and a pro) or a professional the sequence would be the same.
To view, focus and compose the lens would be set in this case F2, to select the correct light meter reading the lens is set (stopped) down to the taking aperture. The modes I've used for this have been mostly manual but lately I found that "AV" worked equally well and the camera metered to the proper exposure. Most times the camera was mounted on a tripod and the shutter was released with a electronic shutter release.
Sequence for taking a photo for me anyway was/is (with the camera mounted on a tripod) focus, compose, stop down to taking aperture, check metering and release the shutter if in AV mode or manual mode to set the shutter speed and release the shutter.
You will find that all makes of digital cameras will function differently so what sequence works for one won't work on others. This meaning I have had digital cameras that wouldn't meter through anything other then the lenses meant specifically for them.
Problems that I've had. Forgetting to stop down to taking aperture (like Duh), not fine focusing (manual), not trusting the in focus indicator, forgetting that the viewfinder is/was only 94% of the scene. Once a little time has been spent with a lens set up like this the rewards are far beyond the trivial annoyances. Have fun with it

It would be nice to know what camera make and model you have. However in AV mode the photographer inputs the aperture (AV meaning Aperture Priority). If you then have the aperture set at (for example) F11 and dim lighting conditions the shutter speed will be long in an attempt to give the correct exposure. If you have a meter reading you see in the viewfinder the needle will be way to the - side of the scale it may be dim enough that attempting to adjust the Aperture a few stops makes no difference in this reading. My though is, if the meter is working in "P" program and you are getting correct exposure then it's user input error rather then meter malfunction.

lens flexible pcb broken change it

OM-20 was basically a upgraded OM-10 with the manual adapter built in and a number of other refinements.

The viewfinder has LED's to show the shutter speed recommended by the camera's lightmeter for the ISO and aperture selected. It also has an exposure compensation indicator (the +/- symbol) and an indicator for flash ready which doubles up as a post-exposure flash confirmation. There is also the indicator lamp to show manual mode has been selected. OM-10 lacks the manual mode lamp and the +/- indicator.

Like the OM-10, the OM-20 is primarily an aperture priority automatic camera. In this mode you set the ISO film speed, choose which aperture you wish to use (with the ability to use the lens depth of field preview button) and then the camera selects the correct shutter speed. The +/- exposure compensation control allows the user to tell the camera to modify the recommended shutter speed by up to two stops either way.

In manual mode, there is no manual metering. The light meter behaves exactly as it does in aperture priority mode and the viewfinder shows the recommended shutter speed and not the manually selected one. Correct metering is therefore a case of adjusting the aperture first, and then choosing the correct shutter speed indicated in the viewfinder. If the user then decides to select a different shutter speed, then the aperture ring must be adjusted to maintain the correct exposure. For example the aperture is set to f8 and the camera recommends 1/60th of a second. The user decides that a faster shutter speed is required and chooses 1/250th, but the viewfinder remains showing 1/60th. In order to keep the same exposure value the user must open the aperture by two full stops to f4. The camera's light meter will detect the new aperture setting and providing the light on the object is unchanged the viewfinder shutter speed display should now show 1/250th as well to confirm the correct adjustment. Alternatively, the user can choose the shutter speed first by looking at what has been set on the control ring (or by turning the ring to the end of its travel and then counting the clicks from there as all experienced OM users do) and then turning the aperture ring until the shutter speed shown in the viewfinder matches what's been manually set.

It all sounds clumsy and complex but is done far more quickly than I've taken to type this and becomes second nature.

Aperture priority metering is selected on the camera by choosing AUTO on the mode selecter. In this mode the shutter speed ring has no effect and the viewfinder always displays the automatically selected shutter speed.

davidsucklin,
You can use the film lens with the D80, but it it not react to the same settings as it did with the film body, the multiplier factor for the focal length is going to be different and it may be stopped down a bit. When you are shooting in aperture mode are you adjusting your shutter and ISO? The camera and the lens have to be communicating the same info to one another inorder for it to work. First set the camera back to auto mode the check the shot to see the settings (f-stop, shutter speed) test them with different ISO's to see what the camera thinks the settings should be, then go back to manual on the camera and lens and try the shutter priority mode with the aperture ring set at the 2.8 to see if it works then change to Aperture mode with the same settings that can take the picture. If it doesn't work keep in mind som of the older D lenses will drop some functionality (like aperture) in certain configurations. You can verfify compatibilty of your specific lens on Nikon's support site.
randy320sgi

Remove lens, CF card, and battery. Leave in a dry and slightly warm place for 24 hours. Clean lens contacts with a cloth or cue tip and eclipse/alcohol.
If the camera doesn't turn on after this, even without CF card and lens attached, then it needs to go to a Canon service centre. Don't tell them you got it wet, and maybe it will get repaired FOC.

That would explain the darkness if the lens is stopped down. It would seem the aperture control is faulty on the camera body. Normally, the aperture remains open until you take the picture. It is only closed down while the shutter is open.