645NII diopter adjustment zero position

lightproof · 05-15-2017, 12:48 PM

Could anyone please tell me how many clicks from the right/left is zero position for the diopter adjustment on 645NII? I just can't seem to find the right spot as my eye keeps accommodating, so I would rather keep the adjustment to zero.

Thanks!

Silent Street · 05-15-2017, 07:00 PM

To arrive at the correct, or most comfortable diopter, focus the lens at infinity.
Look through the viewfinder and rotate the correction until the image has apparent sharp focus. That's it!
Your eye will only "accommodate" to a complimentary diopter, not one which is too far ahead or back, which simply strains it.

lightproof · 06-30-2017, 04:35 AM

I initially tried focusing my eye on the LCD readout inside the viewfinder as usually recommended by camera manufacturers. But I struggled to find the exact diopter value that is comfortable. My eye kept accomodating to each of the two adjacent values as I switched back and forth between them, so I was unable to choose the correct one. That was the reason I asked the question in the first place, as I would prefer to set the adjustment to zero position.

I eventually tried what the user's manual said: point the camera at something bright and adjust the diopter correction unless the AF brackets on the focusing screen look the sharpest. I was actually able to set the adjustment right as the AF brackets are much thinner than the digits on the LCD and it's easier to tell when they are in focus. I even checked the adjustment by wearing glasses I just got which correct my +0.25 diopter in the right eye as well as very slight astigmatism, essentially making my eye to have 100% vision. The astigmatism produces fringing effect on the outlines and makes judging focus harder. I got the glasses to make my eyes tire less in front of the computer screen.

That said, I was quite surprised that the diopter adjustment zero position is exactly in the middle, i.e. 8 clicks to each side. I actually thought that ranging from +1.0 to -3.5 it would have some fixed correction value per click, like 0.25 or 0.5 diopter, but it seems like it's not the case. By the way, I would appreciate it If anyone could prove this conclusion either right or wrong, because there is always a chance that my findings could be incorrect.

05-15-2017, 12:48 PM	#1
lightproof New Member Join Date: May 2017 Posts: 12	645NII diopter adjustment zero position Could anyone please tell me how many clicks from the right/left is zero position for the diopter adjustment on 645NII? I just can't seem to find the right spot as my eye keeps accommodating, so I would rather keep the adjustment to zero. Thanks!

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05-15-2017, 07:00 PM	#2
Silent Street Veteran Member Join Date: Nov 2011 Location: Castlemaine, Victoria, AUS Photos: Albums Posts: 1,151	To arrive at the correct, or most comfortable diopter, focus the lens at infinity. Look through the viewfinder and rotate the correction until the image has apparent sharp focus. That's it! Your eye will only "accommodate" to a complimentary diopter, not one which is too far ahead or back, which simply strains it.

06-30-2017, 04:35 AM	#3
lightproof New Member Join Date: May 2017 Posts: 12 Original Poster	I initially tried focusing my eye on the LCD readout inside the viewfinder as usually recommended by camera manufacturers. But I struggled to find the exact diopter value that is comfortable. My eye kept accomodating to each of the two adjacent values as I switched back and forth between them, so I was unable to choose the correct one. That was the reason I asked the question in the first place, as I would prefer to set the adjustment to zero position. I eventually tried what the user's manual said: point the camera at something bright and adjust the diopter correction unless the AF brackets on the focusing screen look the sharpest. I was actually able to set the adjustment right as the AF brackets are much thinner than the digits on the LCD and it's easier to tell when they are in focus. I even checked the adjustment by wearing glasses I just got which correct my +0.25 diopter in the right eye as well as very slight astigmatism, essentially making my eye to have 100% vision. The astigmatism produces fringing effect on the outlines and makes judging focus harder. I got the glasses to make my eyes tire less in front of the computer screen. That said, I was quite surprised that the diopter adjustment zero position is exactly in the middle, i.e. 8 clicks to each side. I actually thought that ranging from +1.0 to -3.5 it would have some fixed correction value per click, like 0.25 or 0.5 diopter, but it seems like it's not the case. By the way, I would appreciate it If anyone could prove this conclusion either right or wrong, because there is always a chance that my findings could be incorrect.