focus question

dmbfoto · Mar 20, 2009

Hey everyone! I was shooting in manual for the first time this past week and i have a quick question about focus. i have the nikon d40, 18-55 mm and it seemed like anytime i tried to zoom in (even a little bit) it went out of focus. im very new to this and was wondering how to get things to focus when you zoom in manually. could it have been some other settings i needed to change or something? no clue what to do lol...any help would be appreciated! thanks!

Samanax · Mar 20, 2009

After you zoom you have to lock focus again.

AlexColeman · Mar 20, 2009

After you zoom, you have to focus, it is a problem with cheap lenses.

davebmck · Mar 20, 2009

As far as I know, you have to refocus with any lens after you change the focal length (zoom), regardless of the lens cost.

dcclark · Mar 20, 2009

Some lenses are a bit better about staying focused -- my Nikon 18-200mm is very good, for example -- but in general it's just a fact of optics: if you rearrange lenses that much, you're going to have to refocus.

dmbfoto · Mar 20, 2009

how do you refocus again? i know, probably a stupid question, but like i said i had only used auto before this night so it was kinda done for me lol. so i zoom in and do i press the shutter half way and then it focuses or do i have to hit a button or something? because as i was zoomed in i tried just waiting to see what that would and thought maybe it will just come into focus again but it never did.

AlexColeman · Mar 20, 2009

Half depress the shutter again, and it should focus.

dmbfoto · Mar 20, 2009

thanks alex

AlexColeman · Mar 20, 2009

De nada Senor. Check the ebook thread for LOLs.

Mgw189 · Mar 21, 2009

Your original post is very confusing. Does the D40 have a way to zoom without using the lens to do so? At first glance I thought you were using the manual focus not the manual exposure settings. At any rate you got your answer

AlexColeman · Mar 21, 2009

davebmck said:
As far as I know, you have to refocus with any lens after you change the focal length (zoom), regardless of the lens cost.

On my 16-85, 24-70, 70-200, all hold focus very well during zooming. Where as his 18-55 doesn't.... I rest my case.

dmbfoto · Mar 21, 2009

AlexColeman said:
De nada Senor. Check the ebook thread for LOLs.

De nada "senora"

and "hers" doesn't haha.

and i just read some of that thread, very funny.

yeah, i was just looking for a beginner camera so i found this kit my friend suggested. this was the camera he started out with but now he has a D3. im a total noob when it comes to all of this so im still learning what's good, crappy, etc. gear wise.

actually, are you able to use the D40 with any lens Nikon makes or are there limitations? I'm still waiting for the Understanding Exposure book I ordered that everyone told me would help a lot. so hopefully some of my noobness will go away after i read that..probably not though haha.

EhJsNe · Mar 21, 2009

On my manual focus lens (the zoom and zocus controll is all one) theres marks on the barrel that I line up with one of the focus marks when I zoom. (as I zoom, I rotate the lens barrel) Im not exactly sure if thats the right way to do it, but it gets it pretty darn close and Id be satisfied with the results if I didnt refocus.

But with your lens, you probaly have 2 different zoom and focus controlls. The going out of focus has to do with the change in focal length i beleive.

There really isnt a way around this that im aware of. Its just one of those things that happens.

davebmck · Mar 21, 2009

AlexColeman said:
On my 16-85, 24-70, 70-200, all hold focus very well during zooming. Where as his 18-55 doesn't.... I rest my case.

"very well" may be close enough for snap shots, but I wouldn't rely on it if you're looking for really sharp shots. What the heck, you have to press the shutter anyway to take the picture. Why not stop half way for a quick re-focus and know you have it right.