Nikkor 105mm f/2.5 AI-s (on Nikon F3 HP), help

<p>I just bought Nikkor 105mm f/2.5 AI-s version and I don't know much about this lens behavior so I have just one question:</p>

<p><strong>Is there unmarked f-stop between f/4 and f/2.5?</strong><br>

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I have a click there near 2.5 that looks like full stop 2.8, but 2.8 is not marked on lens with white paint (because of lack of space?), so is this normal? If you are owner of one, please help me. :)</p>

<p>Also, on both lenses I have so far 35mm f/2 AI-s and this one, in Nikon F3 HP viewfinder I see small chromatic aberration on the edges of sharp white objects, more on 105mm then in 35mm but still present in both. Is that normal for viewfinder in F3HP and those lenses? I haven't developed film yet to see it directly, I'm quite new in all of this. Sorry for being noob. ;D</p>

<p><em>Thank you all! :)</em></p>

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<p><strong>Is there unmarked f-stop between f/4 and f/2.5?</strong></p>

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<p><strong><br /></strong>Yes, the aperture ring will "click" at f/2.8 (which is unmarked).</p>

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<p>I see small chromatic aberration on the edges of sharp white objects, more on 105mm then in 35mm but still present in both</p>

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<p>Almost every lens will show that - it gets reduced/goes away when you stop the lens down. </p>

<p>Many thanks! ;)</p>

<p>When shooting film with everyday focal lengths such as 35 or 105mm, I would worry a lot more about my technique (steadiness, exposure accuracy, focusing) than things like CA.</p>