Register · Software · Search · Image Upload · Buy & Sell · Reviews · Hosting

Moderated by: guardian
Username   Password

Visit the FM Store · Image Upload · Buy & Sell
FM Forum Rules
Nikon SLRs, primes, and zooms lenses reviews
FM Forums | Nikon-mount SLRs | Join Image Upload
end
Go to previous topic Go to next topic
Taylor Barrett
Offline
Buy and Sell: On
p.1 #1 · Stopping down destroys exposure [Reason Identified]


I'm trying to wrap my head around this one.

Here's the setup (same result on 2 cameras so I've ruled body out, D70 and D300 used).

D300 with Tokina 12-24mm at 12mm. Using center weighted metering, single point center auto focus and auto exposure. ISO 200. Aperture priority. It was aimed at the clouds and should have metered for the sky on all pictures, but once it goes off wide open; everything gets completely blown out.

Set 1:
Wide Open (f/4) at 1/1600th of a second.
This image is copyrighted by the owner

F/5.6 at 1/800th.
This image is copyrighted by the owner

F/8 at 1/400th.
This image is copyrighted by the owner

F/11 at 1/200th.
This image is copyrighted by the owner

I just don't get it. I've done more tests but the results are the same so I'll only post if someone asks. The lens absolutely sucks in shutter and program modes because it chooses apertures smaller than f/4, so the pictures are destroyed from blowing out.

Edited by Taylor Barrett on Jul 05, 2008 at 08:45 PM GMT

Edited on Jul 06, 2008 at 04:45 AM


Jul 06, 2008 at 02:45 AM
Taylor Barrett
Offline
Buy and Sell: On
p.1 #2 · Stopping down destroys exposure [Reason Identified]


Here is one at 24mm on the D70 at F8... focal point was the clouds.

This image is copyrighted by the owner

This is my 2nd copy, the first was a year ago on the D80 and it performed MUCH better as far as I recall.

Here is one from the D80 that looks awesome. F/8 as well!

This image is copyrighted by the owner

Edited on Jul 06, 2008 at 02:54 AM


Jul 06, 2008 at 02:53 AM
williamkazak
Offline
Image Upload: On
p.1 #3 · Stopping down destroys exposure [Reason Identified]


I think your metering technique is faulty. I would be using spot if I pointed it at the clouds. Also, clouds vary in density and intensity so I would never meter on a cloud unless I was just doing cloud pics. You seem to be in incident meter territory anyway.
That is what I use for my pics.

Jul 06, 2008 at 03:23 AM
Taylor Barrett
Offline
Buy and Sell: On
p.1 #4 · Stopping down destroys exposure [Reason Identified]


Believe me, I tried every combination and two cameras and this was the best settings combination. Also, this metering technique works perfectly for my 6 other lenses, so I highly doubt that's the (sole) culprit.

Here's spot metered to satisfy curiosity.
This image is copyrighted by the owner

Edited on Jul 06, 2008 at 03:32 AM


Jul 06, 2008 at 03:31 AM
rc12k
Offline
Buy and Sell: On
p.1 #5 · Stopping down destroys exposure [Reason Identified]


Is your lens actually stopping down? I had a Sigma a few years back that would stick sometimes.

Jul 06, 2008 at 03:42 AM
Ben Horne
Offline
Image Upload: On
p.1 #6 · Stopping down destroys exposure [Reason Identified]


Make sure your lens is actually stopping down. Your exposures should be exactly the same, so there must be a mechanical problem with the aperture. Set your lens to f/22, press the DOF preview button, and look into the front of your lens with a flashlight. I bet the aperture is not actually stopping down.

Jul 06, 2008 at 03:46 AM
Taylor Barrett
Offline
Buy and Sell: On
p.1 #7 · Stopping down destroys exposure [Reason Identified]


rc12k wrote:
Is your lens actually stopping down? I had a Sigma a few years back that would stick sometimes.


That's a really good question - that would make complete sense. The aperture appears in the Exif data but it would explain everything... how could I test this?

Jul 06, 2008 at 03:46 AM
Taylor Barrett
Offline
Buy and Sell: On
p.1 #8 · Stopping down destroys exposure [Reason Identified]


This appears to be confirmed from Ben's test. I did the 50mm first and noted the difference between f/1.8 and f/22 when pressing the DOF preview button (it was a huge, obvious difference, obviously), then did the same with the 12-24mm at f/4 and f/22, and there was no change between apertures.

Now I'm sad. Time to speak with the seller.

Good detective work, fellows. I never would have suspected that. This is why I turn to Fred Miranda in a pinch

Edited on Jul 06, 2008 at 03:54 AM


Jul 06, 2008 at 03:53 AM
gfiksel
Offline
Image Upload: On
p.1 #9 · Stopping down destroys exposure [Reason Identified]


Was ISO staying the same? Or, it was on Auto and changing from shot to shot. You can check the EXIF. Another way to check the lens is to go to Manual , set the fixed ISO, and vary the aperture and the shutter speed manually.

Jul 06, 2008 at 04:09 AM
Taylor Barrett
Offline
Buy and Sell: On
p.1 #10 · Stopping down destroys exposure [Reason Identified]


gfiksel wrote:
Was ISO staying the same? Or, it was on Auto and changing from shot to shot. You can check the EXIF. Another way to check the lens is to go to Manual , set the fixed ISO, and vary the aperture and the shutter speed manually.


Like I said in the first post, the ISO was 200 for all shots. I am completely certain that the two previous to my last reply are correct because as they said, stopping down does not physically close the aperture up.

Jul 06, 2008 at 04:16 AM
gugs
Offline
Image Upload: Off
p.1 #11 · Stopping down destroys exposure [Reason Identified]


I have had exactly the same problem with the D200... but after say 100 pics, I could only shoot fully open with all my lenses. The problem was in the camera, the aperture lever mechanism was not functioning properly. I am not saying this is the case here, but it has to do with the aperture. Could be the lens not closing down, or it could be the camera not closing down anymore (like in my case). The D200 needed to go to service BTW.

Guy

Jul 06, 2008 at 05:46 AM
Taylor Barrett
Offline
Buy and Sell: On
p.1 #12 · Stopping down destroys exposure [Reason Identified]


gugs wrote:
I have had exactly the same problem with the D200... but after say 100 pics, I could only shoot fully open with all my lenses. The problem was in the camera, the aperture lever mechanism was not functioning properly. I am not saying this is the case here, but it has to do with the aperture. Could be the lens not closing down, or it could be the camera not closing down anymore (like in my case). The D200 needed to go to service BTW.

Guy


This is definitely the aperture, I did more tests in manual where I kept the shutter and ISO the same but changed the aperture and the pictures were the same no matter what the aperture was set to.

The body is a brand new D300 so hopefully that's not the issue, but I highly doubt it is because the previous owner couldn't find a single keeper with an aperture that wasn't f/4 now that I've asked him about it. My other lenses work fine.

Such is life.

Jul 06, 2008 at 06:40 AM
zoetmb
Offline
Image Upload: Off
p.1 #13 · Stopping down destroys exposure [Reason Identified]


I had the same issue with a Nikon 18-70mm. It took me a long time to figure out because I tend to shoot in very low light and in low light, the lens would have been at 2.8 anyway, but it would overexpose in bright light. Look on the body side of the lens. There's a small lever that controls the aperture, but it's spring loaded and you should feel some tension. On my lens, the spring had apparently popped out or got lost inside the lens. Had it fixed and it worked fine.

This might not be a costly repair, so if you got a good deal on the lens, you might want to keep it.

Jul 06, 2008 at 03:30 PM
EB-1
Offline
Image Upload: Off
p.1 #14 · Stopping down destroys exposure [Reason Identified]


What are those weird dark areas around the top edges? Lens hood or something internal?

EB

Jul 06, 2008 at 03:40 PM
shakes
Offline
Buy and Sell: On
p.1 #15 · Stopping down destroys exposure [Reason Identified]


Those spots are the lens hood. I picked up the hood from a local store right after I bought that lens used. Apparently it was for a different lens. I am the one that sold Taylor the lens.

Taylor,
I'm replying to your email. We will get this worked out one way or another.

Doug

Edited on Jul 06, 2008 at 04:01 PM


Jul 06, 2008 at 03:48 PM
Taylor Barrett
Offline
Buy and Sell: On
p.1 #16 · Stopping down destroys exposure [Reason Identified]


Shot you one back doug. I'm sure we'll get this all worked out.

Jul 06, 2008 at 05:33 PM

FM Forums | Nikon-mount SLRs | Join Image Upload
end
  Go to previous topic Go to next topic

You are not logged in. Login or Register

  Username   Password  
Lost password?