D90 User Group (Thread IV)

[quizesilver]

Hi guys, this is my first post after trying out with my new D90.
I been trying to get a nice blur background for a portrait shot with the 18-105 kit lens with aperture priority. But always the picture came out everything in focus. Think i must be not doing it the correct way.

set the focusing to AF-Single
if AF-Auto, most pro all will be focus/sharp

 

[ZerocoolAstra]

set the focusing to AF-Single
if AF-Auto, most pro all will be focus/sharp

bro... this is a Depth of Field issue, not an auto-focus issue.

If DOF is thin, and you have 2 subjects standing at very different distances from camera, no matter what AF mode you set the camera to, you won't be able to get both sharp.

 

[pasay]

set the focusing to AF-Single
if AF-Auto, most pro all will be focus/sharp

bro... this is a Depth of Field issue, not an auto-focus issue.

If DOF is thin, and you have 2 subjects standing at very different distances from camera, no matter what AF mode you set the camera to, you won't be able to get both sharp.

sorry quize, kinda agree with ZCA on this one. hosann was taking a portrait and wanted to blur his background. his subject and background is on different focusing planes, your camera can only focus on one plane at a time, thereby those out of the focused plane will be blurred (hence the term "out-of-focus") no matter what auto-focusing more you use.

hosann, kit lens will still produce blur, even at f5.6 at the zoom end. coz there are other factors besides aperture at play to produce background blur: focal length, distance of camera to subject, distance of subject to background. only that bigger apertures like f2.8 or lower will be easier and give better bokeh.

 

[quizesilver]

bro... this is a Depth of Field issue, not an auto-focus issue.

If DOF is thin, and you have 2 subjects standing at very different distances from camera, no matter what AF mode you set the camera to, you won't be able to get both sharp.

sorry quize, kinda agree with ZCA on this one. hosann was taking a portrait and wanted to blur his background. his subject and background is on different focusing planes, your camera can only focus on one plane at a time, thereby those out of the focused plane will be blurred (hence the term "out-of-focus") no matter what auto-focusing more you use.

hosann, kit lens will still produce blur, even at f5.6 at the zoom end. coz there are other factors besides aperture at play to produce background blur: focal length, distance of camera to subject, distance of subject to background. only that bigger apertures like f2.8 or lower will be easier and give better bokeh.

but if i am not wrong, while doing matrix / 3D focusing. those that is pick up by the camera ie front and back will be in focus.
is it ?

only when u choose the "subject" (AF-single) which is the one focus point in the front and the behind not selected will become "blur"

anyway tml we at bmw then i try again. newbie still

btw hosann, what zca mention on being nearer to the subject will create more blur is true. esp if the background is some distance away.

 

[hossann]

Thanks guys, managed to have a quick try at 105mm f/5.6. Finally i got a slight blur background. Being busy last few days so cant have a proper try out on the cam. Looking forward to weekend to try out more.

I notice there is a flower-shape-like thing in the bundle with the camera. When to use this thing? Under what condition?

Agian thanks. All feedbacks are very informative to me.

 

[weegk]

Thanks guys, managed to have a quick try at 105mm f/5.6. Finally i got a slight blur background. Being busy last few days so cant have a proper try out on the cam. Looking forward to weekend to try out more.

Agian thanks. All feedbacks are very informative to me.

Great . . . our kit lens is not that bad . . .

of course comparing to prime lens in terms of bokeh maybe a bit difficult but still can do wonders with it . . . just need to experiment more with it.

 

[Smiles88]

Thanks guys, managed to have a quick try at 105mm f/5.6. Finally i got a slight blur background. Being busy last few days so cant have a proper try out on the cam. Looking forward to weekend to try out more.

I notice there is a flower-shape-like thing in the bundle with the camera. When to use this thing? Under what condition?

Agian thanks. All feedbacks are very informative to me.

I believe what you're talking about is the lens hood. It's used to reduce stray lights. It can also be a form of buffer for your lens IF you drop it. And it's commonly used.

 

[weegk]

just to add on to Smile88, the lens hood is normally used during the day time to prevent glare/flare to to your lens . . .

 

[hossann]

I believe what you're talking about is the lens hood. It's used to reduce stray lights. It can also be a form of buffer for your lens IF you drop it. And it's commonly used.

just to add on to Smile88, the lens hood is normally used during the day time to prevent glare/flare to to your lens . . .

So you guys usually have the lens hood on?

 

[hossann]

Great . . . our kit lens is not that bad . . .

of course comparing to prime lens in terms of bokeh maybe a bit difficult but still can do wonders with it . . . just need to experiment more with it.

Finally accomplish something. Starting to love it more than my P&S camera. Will continue to practice on bokeh then later move on to do some shooting for sports (moving object? hehehe)

 

[Smiles88]

So you guys usually have the lens hood on?

I have it on all the time. Just a matter of whether is it reversed or not. :bsmilie: I use it when I find the need to.

 

[ZerocoolAstra]

but if i am not wrong, while doing matrix / 3D focusing. those that is pick up by the camera ie front and back will be in focus.
is it ?

only when u choose the "subject" (AF-single) which is the one focus point in the front and the behind not selected will become "blur"

anyway tml we at bmw then i try again. newbie still

btw hosann, what zca mention on being nearer to the subject will create more blur is true. esp if the background is some distance away.

woah woah woah.... hold your horses there...

Don't confuse METERING with FOCUSING
This 'matrix' thingy is referring to metering, if I'm not mistaken.

Ok first you need to understand how the camera focuses, and what is 'focus plane'.

If 2 subjects are on very different focus planes, and the depth of field is insufficient to cover them, you will not be able to get both in focus in 1 shot, no matter what super-duper AF mode you employ.

 

[ZerocoolAstra]

Thanks guys, managed to have a quick try at 105mm f/5.6. Finally i got a slight blur background. Being busy last few days so cant have a proper try out on the cam. Looking forward to weekend to try out more.

I notice there is a flower-shape-like thing in the bundle with the camera. When to use this thing? Under what condition?

Agian thanks. All feedbacks are very informative to me.

@ 105mm f/5.6, depth of field should be the thinnest for the kit lens.
If you're standing 2 or 3m from your subject, and the background is like 30-50m away, you should be able to achieve 'decent' subject isolation.

Certainly this effect (pls avoid the term 'bokeh effect'... it's very cliche and also incorrect) is very novel for PnS upgraders...

If you want even thinner DOF or smoother bokeh, unfortunately the only way is to cough up more money and get a fast tele prime :devil:

 

[hossann]

@ 105mm f/5.6, depth of field should be the thinnest for the kit lens.
If you're standing 2 or 3m from your subject, and the background is like 30-50m away, you should be able to achieve 'decent' subject isolation.

Certainly this effect (pls avoid the term 'bokeh effect'... it's very cliche and also incorrect) is very novel for PnS upgraders...

If you want even thinner DOF or smoother bokeh, unfortunately the only way is to cough up more money and get a fast tele prime :devil:

Understand and thank you very much for your advise.

 

[weegk]

I have it on all the time. Just a matter of whether is it reversed or not. :bsmilie: I use it when I find the need to.

same same . . . so that i won't misplace it too . . .

except my that 10-24 lens hood . . . don't like it, too big and bulky . . .

 

[kriegsketten]

@ 105mm f/5.6, depth of field should be the thinnest for the kit lens.
If you're standing 2 or 3m from your subject, and the background is like 30-50m away, you should be able to achieve 'decent' subject isolation.

Certainly this effect (pls avoid the term 'bokeh effect'... it's very cliche and also incorrect) is very novel for PnS upgraders...

If you want even thinner DOF or smoother bokeh, unfortunately the only way is to cough up more money and get a fast tele prime :devil:

I used to be the PnS upgrader you mentioned... :embrass: Anyway, since ZCA has kindly enlightened you, time to move on from that... :thumbsup:

Agreed, nothing will ever beat the fast primes (f/1.2, f/1.4, f/1.8, f/2.0) in terms of buttery bokehs. The f/2.8 zooms come a distant second... Happying poisoning yourself with superb prime lenses in the months ahead... :devil: You'll be sleepless thinking about which one to go for... D90 is a superb starter and opener to a great number of lens options (except for AiS legacy lenses which you'll need assistance from light meters)...

 

[pasay]

but if i am not wrong, while doing matrix / 3D focusing. those that is pick up by the camera ie front and back will be in focus.
is it ?

only when u choose the "subject" (AF-single) which is the one focus point in the front and the behind not selected will become "blur"

anyway tml we at bmw then i try again. newbie still

btw hosann, what zca mention on being nearer to the subject will create more blur is true. esp if the background is some distance away.

matrix is for metering, 3D is for AF-point selection. as i've said, the camera can only focus on ONE focus plane. how thick or thin that focus plane is will determine how much is blurred. that's your DoF.

actually, you're already said it in your post. if background is some distance away, then even with a large DoF, it still isn't enough to cover that distance between subject and background, hence the blur.

 

[pasay]

So you guys usually have the lens hood on?

usually i have the hood reversed when the cam is stowed for transport or storage. then i put it the right way and leave the lens cap off when i'm out shooting. the hood prevents bumps and scratches on the lens' front element while walking. it also reduces stray light and flare from entering the lens.

 

[NoobCake]

ahhh i'm back. . last week had duties =( can't join u guys at all (for outings and anything. .) don't even have time to post anything =.= "

Sad I've got a problem. i compared my D90 with my workplace's my sensor seems yellowish. . and when i switch to live view and place on a white back ground there's a lot of yellowish line flickers. While i take some fast shots on it. . the there are yellowish things on my image.

Is my sensor spoil already? its only 2 months old " i've taken very good care of it.

 

[ZerocoolAstra]

ahhh i'm back. . last week had duties =( can't join u guys at all (for outings and anything. .) don't even have time to post anything =.= "

Sad I've got a problem. i compared my D90 with my workplace's my sensor seems yellowish. . and when i switch to live view and place on a white back ground there's a lot of yellowish line flickers. While i take some fast shots on it. . the there are yellowish things on my image.

Is my sensor spoil already? its only 2 months old " i've taken very good care of it.

could be different White Balance settings.
Hard to be certain.

don't jump to conclusion yet!