Battery required for sharp OVF focusing?

Air Cooled Nut said:

Camera: Nikon Df

I removed the battery from my Df to charge it. I then looked through the viewfinder with my macro zoom attached to see how physically close I could get to a subject and still focus on it. I could not get the image into sharp focus! I thought it was my diopter adjustment so I rotated the wheel both directions but I could not obtain sharp focus. What the hell?!

I noticed that I did not see the black lines in my OVF (the one-thirds grid) and I remembered that it could be turned on/off. So I put the battery back in and when I looked through the viewfinder with the power off the focusing screen was sharp! I took the battery out and the focusing screen was definitely not sharp. Looking through the OVF I inserted the battery and the focusing screen suddenly sharpened. Say what?

So is this normal for digital SLRs? What is happening that requires the battery to be installed in order to have a clear focusing screen?

Click to expand...

Dave Sanders said:

Air Cooled Nut said:

Camera: Nikon Df

I removed the battery from my Df to charge it. I then looked through the viewfinder with my macro zoom attached to see how physically close I could get to a subject and still focus on it. I could not get the image into sharp focus! I thought it was my diopter adjustment so I rotated the wheel both directions but I could not obtain sharp focus. What the hell?!

I noticed that I did not see the black lines in my OVF (the one-thirds grid) and I remembered that it could be turned on/off. So I put the battery back in and when I looked through the viewfinder with the power off the focusing screen was sharp! I took the battery out and the focusing screen was definitely not sharp. Looking through the OVF I inserted the battery and the focusing screen suddenly sharpened. Say what?

So is this normal for digital SLRs? What is happening that requires the battery to be installed in order to have a clear focusing screen?

Click to expand...

Click to expand...

Dave Sanders said:

Air Cooled Nut said:

Camera: Nikon Df

I removed the battery from my Df to charge it. I then looked through the viewfinder with my macro zoom attached to see how physically close I could get to a subject and still focus on it. I could not get the image into sharp focus! I thought it was my diopter adjustment so I rotated the wheel both directions but I could not obtain sharp focus. What the hell?!

I noticed that I did not see the black lines in my OVF (the one-thirds grid) and I remembered that it could be turned on/off. So I put the battery back in and when I looked through the viewfinder with the power off the focusing screen was sharp! I took the battery out and the focusing screen was definitely not sharp. Looking through the OVF I inserted the battery and the focusing screen suddenly sharpened. Say what?

So is this normal for digital SLRs? What is happening that requires the battery to be installed in order to have a clear focusing screen?

--
Toby

Click to expand...

Yes, I think the LCD overlay needs to be powered to make itself transparent, thus allowing focusing. Has been this way for quite a while, at least since my D700, possibly earlier.

Click to expand...

michaeladawson said:

Dave Sanders said:

Air Cooled Nut said:

Camera: Nikon Df

I removed the battery from my Df to charge it. I then looked through the viewfinder with my macro zoom attached to see how physically close I could get to a subject and still focus on it. I could not get the image into sharp focus! I thought it was my diopter adjustment so I rotated the wheel both directions but I could not obtain sharp focus. What the hell?!

I noticed that I did not see the black lines in my OVF (the one-thirds grid) and I remembered that it could be turned on/off. So I put the battery back in and when I looked through the viewfinder with the power off the focusing screen was sharp! I took the battery out and the focusing screen was definitely not sharp. Looking through the OVF I inserted the battery and the focusing screen suddenly sharpened. Say what?

So is this normal for digital SLRs? What is happening that requires the battery to be installed in order to have a clear focusing screen?

Click to expand...

Click to expand...

Click to expand...

michaeladawson said:

Dave Sanders said:

Yes, I think the LCD overlay needs to be powered to make itself transparent, thus allowing focusing. Has been this way for quite a while, at least since my D700, possibly earlier.

Click to expand...

Click to expand...

Dave Sanders said:

Yes, I think the LCD overlay needs to be powered to make itself transparent, thus allowing focusing. Has been this way for quite a while, at least since my D700, possibly earlier.

Click to expand...

michaeladawson said:

Dave Sanders said:

Air Cooled Nut said:

Camera: Nikon Df

I removed the battery from my Df to charge it. I then looked through the viewfinder with my macro zoom attached to see how physically close I could get to a subject and still focus on it. I could not get the image into sharp focus! I thought it was my diopter adjustment so I rotated the wheel both directions but I could not obtain sharp focus. What the hell?!

I noticed that I did not see the black lines in my OVF (the one-thirds grid) and I remembered that it could be turned on/off. So I put the battery back in and when I looked through the viewfinder with the power off the focusing screen was sharp! I took the battery out and the focusing screen was definitely not sharp. Looking through the OVF I inserted the battery and the focusing screen suddenly sharpened. Say what?

So is this normal for digital SLRs? What is happening that requires the battery to be installed in order to have a clear focusing screen?

Click to expand...

Click to expand...

Click to expand...

a_c_skinner said:

Same for the D200. It may be the same for the D800, I've not looked.

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