marcus_miller3

this is very interesting and smart solution to give new life to 80-200 zoom lens. I would like to do the same to my 80-200 because it is also

affected by back focus and -20 is not enough to correct it.

Could someone clearly describe how to disassemble the lens and have full access to the brush focus? Is it a simple operation or could

potentially damage the lens? A picture that describe which screw to remove would be very useful for everyone. Thanks.

<p>Hi,<br>

thanks a lot for your support. I observed the same behaviour on my previous D600. In my old D300 everything worked fine as expected.<br>

I forgot to tell you that I set also shutter release button to lock the exposure (anyhow I don’t press this button during this test).<br>

I tried to assign the focus lock only to the AE/AF button and it has the issue of the AF-ON.<br>

I’m sorry for that but it sounds quite strange that in my D600 and D800 I observe the same issue.<br>

I don’t think that my D800 has some faulty condition but I have some setting that cause this trouble. These particular settings probably cause this issue and in my opinion this is firmware bug.<br>

I hope someone else will reply to my post and see what happen.<br>

I can try also to re-install the firmware (if the camera will let me do that since the new one is already installed).<br>

Thanks.</p>

<p>Hi,<br>

actually the exposure meter change the value when I move the camera AF-ON is pressed. But the reading value is wrong because when I release the AF-ON button the reading value change dramatically.<br>

Try to do this:<br>

Use the AF-S mode<br>

Use Aperture priority exposure mode<br>

Set the aperture lens<br>

Set the camera to focus only with AF-ON button<br>

Use a fixed ISO (for instance ISO 400) and NOT auto.<br>

Point the camera toward a subject and focus with AF-ON<br>

Hold the AF-ON pressed and move the camera toward the window where there is a big difference in brightness. Now the reading value is for instance 1/250s.<br>

Then release the AF-ON button. Now Does the reading exposure value change? When I release the button in my D800 the value change from 1/250s to 1/4000s for instance.<br>

Try to do something like that and tell me if you observe the same issue.</p>

Sera Jacques,

Yesterday I've tried again to test the AF-ON button and the problem with exposure meter accours only in AF-S mode.

In AF-S mode the exposure meter report bad reading value when I move the camera.

In AF-C mode the reading is perfect.

Please if someone here is usino Nikon D800 try to test it.

Probably it is a firmware bug.

<p><br>

</p>

<p >Dear Jacques,</p>

<p >many thanks for your reply.</p>

<p >Now I use the shutter-release half-press technique to lock focus and exposure and then I recompose. With just the forefinger I can control two parameters.</p>

<p >But also the AF-ON button could help me when I use the AF-C capability and I don’t want to switch from AF-C to AF-S all the time. </p>

<p >But as I’ve already mentioned in my previous post, I noticed that holding the AF-ON button and point the camera toward different light source, the light meter change exposure value. This is normal because as you reported the AF-ON only lock the focus. </p>

<p >The strange thing is that when you release the AF-ON button the exposure reading show now a totally different value.</p>

<p >If you own a D800 try and verify this issue.</p>

<p >I noticed this behaviour also with D600.</p>

<p >In my previous D300 everything was working as expected. The AF-ON locks the focus and the light meter always reads a correct value.</p>

<p > </p>

<p >Do you have any explanation or I’m doing something wrong?</p>

<p >Thanks.</p>

<p>I’m trying to use the focus recompose technique because it could be useful for me.<br /> Set my D800 accordingly the suggested set-up:<br /> AF-S Priority Selection: FOCUS<br /> AF Activation set to OF-ON button ONLY.<br /> AF Area mode set to SINGLE POINT.<br>

The camera works exactly as reported in your description.<br /> But when you use this technique for focus and recompose, what about the exposure meter? I mean, if I focus on the face of my subject then also the exposure must be taken from his face. But with AF-ON button to hold the exposure I must press also the shutter button.<br /> Do you have any suggestion to hold focus and take the correct exposure?<br>

I noticed also some interesting behaviour:<br /> - When I press and keep AF-ON pressed, also the exposure seems to be locked. I wrote seems because the exposure reading value has a strange reading. Try to acquire focus with AF-ON, keep AF-ON pressed, and then move completely the camera to a different light source and intensity. The exposure meter reads a certain value. Now release the AF-ON button. The exposure meter reads a totally different value.<br>

I believe that the AF-ON must lock only the autofocus and not the exposure.<br>

Thanks for your comments.</p>

<p>I’m trying to use the technique focus and recompose technique because it could be useful for me.<br /> Set my D800 accordingly the suggested set-up:<br /> AF-S Priority Selection: FOCUS<br /> AF Activation set to OF-ON button ONLY.<br /> AF Area mode set to SINGLE POINT.<br>

The camera works exactly as reported in your description.<br /> But when you use this technique for focus and recompose, what about the exposure meter? I mean, if I focus on the face of my subject then also the exposure must be taken from his face. But with AF-ON button to hold the exposure I must press also the shutter button.<br /> Do you have any suggestion to hold focus and take the correct exposure?<br>

I noticed also some interesting behaviour:<br /> - When I press and keep AF-ON pressed, also the exposure seems to be locked. I wrote seems because the exposure reading value has a strange reading. Try to acquire focus with AF-ON, keep AF-ON pressed, and then move completely the camera to a different light source and intensity. The exposure meter reads a certain value. Now release the AF-ON button. The exposure meter reads a totally different value.<br>

I believe that the AF-ON must lock only the autofocus and not the exposure.<br>

Thanks for your comments.</p>

<p>Dear Jacques,<br>

when you use this technique for focus and recompose, what about the exposure meter? I mean, if I focus on the face of my subject then also the exposure must be taken from his face. But with AF-ON button to hold the exposure I must press also the shutter button.<br />Do you have any suggestion to hold focus and take the correct exposure?<br>

I noticed also some interesting behaviour:<br /> - When I press and keep AF-ON pressed, also the exposure seems to be locked. I wrote seems because the exposure reading value has a strange reading. Try to acquire focus with AF-ON, keep AF-ON pressed, and then move completely the camera to a different light source and intensity. The exposure meter reads a certain value. Now release the AF-ON button. The exposure meter reads a totally different value.<br>

I believe that the AF-ON must lock only the autofocus and not the exposure.<br>

Thanks for your comments.<br>

P.S. I'm using Nikon D800 with latest firmware.</p>

<p>I’m trying to use this technique because it could be useful for me.<br>

Set my D800 accordingly the suggested set-up:<br>

AF-S Priority Selection: FOCUS<br>

AF Activation set to OF-ON button ONLY.<br>

AF Area mode set to SINGLE POINT.<br>

The camera works exactly as reported in your description at point 3. AF-S Mode.<br>

But when you use this technique for focus and recompose, what about the exposure meter? I mean, if I focus on the face of my subject then also the exposure must be taken from his face. But with AF-ON button to hold the exposure I must press also the shutter button.<br>

Do you have any suggestion to hold focus and take the correct exposure?<br>

I noticed also some interesting behaviour:<br>

- When I press and keep AF-ON pressed, also the exposure seems to be locked. I wrote seems because the exposure reading value has a strange reading. Try to acquire focus with AF-ON, keep AF-ON pressed, and then move completely the camera to a different light source and intensity. The exposure meter reads a certain value. Now release the AF-ON button. The exposure meter reads a totally different value.<br>

I believe that the AF-ON must lock only the autofocus and not the exposure.<br>

Thanks for your comments.</p>