kumar_b

<p>Thanks, Stephen. Good to know that there is atleast one lens for which such data is provided. Is it accessible online someplace ?</p>

<p>I just checked NIkon's manual. It has a plot for effective f-stop vs focus distance. I think one can indirectly infer the magnification from this. But, something more direct would have been nice. Is there some other instruction sheet available ? <br>

Another way to figure out would be to just play with the lens. It seems like the dial on the lens marks both distance and magnification ratios.</p>

<p>Thanks to everyone for the responses. After reading thro some of the links, I probably understand the macro designs a little better. Still, it would be great if manufacturers just gave a plot of the magnification as a function of focus distance. Or, maybe they do and I could not find it. If anyone has a link to such a plot for macro designs, please do share it. <br>

And I appreciate the concern of many that 40mm is way too short for macro. I don't plan on doing "serious macro". But, I think being able to get close enough to get bigger magnifications than 1:6 on a such a wide-ish lens is also a fun thing to do. Besides, this is very easy on my wallet :)</p>

<p>Hi Jos, you were quick to respond. Thanks! <br /> (But, it is now wierd that I have ended up posting the question on two separate threads. Sorry about the confusion. Whats the etiquete for such scenarios ? Being able to delete one's posts atleast withing a few minutes of posting might help! )<br /> Is it just the flat fielding that is different in macros ? When I look @ the numbers from Nikon, what jumps out for me is that the min. focusing distance for the 40mm macro is half that of the 35mm non-macro. But, its max magnification is 6 times (as opposed to a naive doubling that one might have expected). So, it seems to me that a lot more is different in a macro lens design. And I completely understand when you say "shoot and be happy". That is what I plan to do. But, I am still curious about the theory. If you think this forum is not the right place for a technical response, you could point me to a reference where I can find more info. That would be fine as well.</p>

<p>I just realized this question is related to discussions in this thread : <a href="00ZHhl?start=40">http://www.photo.net/nikon-camera-forum/00ZHhl?start=40</a> and this posted it there I request one of the admins to delete this post. </p>

<p>I will be buying the 40mm Micro Nikkor sometime soon. This will be my first real macro lens and I have thus been reading around to get the best out of it. So, here is a question for the experts. <br />Is there something to quantify the extent to which macro lenses correct for perspective distortion when up close ? Consider the following hypothetical scenarios for taking head shots (on DX sensors) : <br />a) 40mm macro close to the subject vs 40mm non-macro at same distance - <br />b) 40mm macro close to subject vs 85mm macro further from subject <br />c) 40mm macro close to subject vs 85 mm non-macro further from the subject<br />Let us assume that there is enough light that the possible difference in max appertures for macro and non-macro lenses is not a factor here. <br />Now, my guesses are <br />a) 40mm macro is better<br />b) 85mm macro is better<br />c) Not sure<br />Am I right on a) and b ) and what is the best way to figure out the answer for c) ?<br>

Thanks in advance. This is my first post here.<br>

(I posted this as a separate question and then realized this thread might be a better place since my question is related to the discussions here) </p>

<p>I will be buying the 40mm Micro Nikkor sometime soon. This will be my first real macro lens and I have thus been reading around to get the best out of it. So, here is a question for the experts. <br>

Is there something to quantify the extent to which macro lenses successfully correct for perspective distortion when up close ? Consider the following hypothetical scenarios for taking head shots (on DX sensors) : <br>

a) 40mm macro close to the subject vs 40mm non-macro at same distance - <br>

b) 40mm macro close to subject vs 85mm macro further from subject <br>

c) 40mm macro close to subject vs 85 mm non-macro further from the subject<br>

Let us assume that there is enough light that the possible difference in max appertures for macro and non-macro lenses is not a factor here. <br>

Now, my guesses are <br>

a) 40mm macro is better<br>

b) 85mm macro is better<br>

c) Not sure<br>

Am I right on a) and b ) and what is the best way to figure out the answer for c) ?<br>

I can ofcourse go to the nearest camera shop and shoot to observe the difference .But, I wanted to ask here anyway. <br>

Thanks in advance. This is my first post here.<br>

(I know this question might have relevance for non-Nikon owners as well. But, I could not find an obvious place for this question. Sorry if it is misplaced!) </p>