We are in seattle and heading for victoria and Butchart gardens later this week.
my 70-180 macro lens does not auto-focus and the view is very dark when i look thru the viewfinder.
cleaned the contacts and no better. All other lenses work fine.
Anyone with any ideas as to what is screwy?
Thanks -
Sandy
I know this is gonna sound dumb, but isn't there a small switch there that lets you set it on manual? Make sure that's not switched. I believe it's labeled M and A. Make sure it's switched to A. Only because I have done this before myself....
Does DOF Preview work? It could be that the aperture blades are stuck. Does the camera think it's metering properly in any of the auto-modes? If so, maybe you've got something on that's causing extreme exposure compensation?
If you need a repair shop, try Photo-Tronics on Dexter Ave. between Mercer and Denny, downtown/South Lake Union area. Also, the staff at Glazer's Camera, nearby, is often very helpful at troubleshooting such problems.
I think a key element here is that the viewfinder is very dark. When the lens is off-camera, can you see through it and does it look normal or is there some optical blockage? Is it wide open or stopped down? It should only stop down when on-camera AND when activating the shutter (or the DOF preview). If it were stopped down for whatever reason (malfunction), the viewfinder would be quite dark and there might not be enough light for the auto-focus system to work - which is what you observe.
Another possibility: the mirror could be out of alignment or not seated properly in its rest position. Then, it would not reflect light properly into the prism and circuitry. Is the viewfinder looking normally bright with another lens mounted, or no lens? Note added after posting: I reread your post and saw that the other lenses work fine - that would eliminate the mirror issue.
Another couple of thoughts: does the lens have a manual aperture ring that you could try? Does the lens respond to aperture changes via the controls on the body? Does it focus manually, on-camera or off-camera?
I hope it's just a simple thing and that this gets sorted out in time for your trip. Roger.
Just saw this, Sandy. If you are still in Seattle on the 5th, I'd recommend a stop at Glazer's. If they can't help you fix it, they have a good rental shop at reasonable prices.
This sounds like a problem with the diaphragm blades in the lens.
Looking at images via Google for this lens it has a physical aperture ring (not a "G" type lens) with a minimum aperture lock. On modern Nikon bodies you set the lens aperture to minimum (f/32 typically on a micro) and use a fingernail to slide the tiny lock to line up with the red mark (back of the lens, closest to the body). With the lens un-mounted from the camera and no lens caps look through the lens - the hole should be very small.
While looking through the lens use your fingertip to move the diaphragm lever - it is the small black piece at the lens mount next to the chrome plated part. This should move freely and spring back and move the diaphragm blades to the open position. You'll see the "light" hole in the lens open to maximum position. This is what happens every time you release the shutter on the camera to get the lens to the set aperture.
If the lever won't move then you are always looking through the mounted lens at minimum aperture and the viewfinder will be dark.
The lever won't move if it has been damaged - knocked against something for instance. Or if a diaphragm blade has come loose and is jamming the diaphragm. That happened 20-30 years ago to me on my ancient manual focus Nikkor 200/4 macro.
A repair shop can fix this but it requires partially disassembling the lens to get to the blades.
If you don't have the aperture ring locled at minimum then you should be able to see a large light circle through the lens, and watch the blades close as you turn the aperture ring to smaller settings.
Thanks to everyone - it seems to be an aperture problem, as it works adequately when I open and close the aperture manually before every shot.
It does not work otherwise. Not very convenient, but at least i have a macro lens! I'll take it in to the repair when we get home.
Sandy
Discussion
8 repliesmy 70-180 macro lens does not auto-focus and the view is very dark when i look thru the viewfinder.
cleaned the contacts and no better. All other lenses work fine.
Anyone with any ideas as to what is screwy?
Thanks -
Sandy
Thanks, though
Sandy
Another possibility: the mirror could be out of alignment or not seated properly in its rest position. Then, it would not reflect light properly into the prism and circuitry. Is the viewfinder looking normally bright with another lens mounted, or no lens? Note added after posting: I reread your post and saw that the other lenses work fine - that would eliminate the mirror issue.
Another couple of thoughts: does the lens have a manual aperture ring that you could try? Does the lens respond to aperture changes via the controls on the body? Does it focus manually, on-camera or off-camera?
I hope it's just a simple thing and that this gets sorted out in time for your trip. Roger.
Looking at images via Google for this lens it has a physical aperture ring (not a "G" type lens) with a minimum aperture lock. On modern Nikon bodies you set the lens aperture to minimum (f/32 typically on a micro) and use a fingernail to slide the tiny lock to line up with the red mark (back of the lens, closest to the body). With the lens un-mounted from the camera and no lens caps look through the lens - the hole should be very small.
While looking through the lens use your fingertip to move the diaphragm lever - it is the small black piece at the lens mount next to the chrome plated part. This should move freely and spring back and move the diaphragm blades to the open position. You'll see the "light" hole in the lens open to maximum position. This is what happens every time you release the shutter on the camera to get the lens to the set aperture.
If the lever won't move then you are always looking through the mounted lens at minimum aperture and the viewfinder will be dark.
The lever won't move if it has been damaged - knocked against something for instance. Or if a diaphragm blade has come loose and is jamming the diaphragm. That happened 20-30 years ago to me on my ancient manual focus Nikkor 200/4 macro.
A repair shop can fix this but it requires partially disassembling the lens to get to the blades.
If you don't have the aperture ring locled at minimum then you should be able to see a large light circle through the lens, and watch the blades close as you turn the aperture ring to smaller settings.
It does not work otherwise. Not very convenient, but at least i have a macro lens! I'll take it in to the repair when we get home.
Sandy