Depth Of Field Problems w/18-55mm AF-S Kit Lens

J

JA Warrior

New member
I've been experimenting and getting better with close-up product shots using the Nikon D5100's 18-55mm AF-S kit lens, but I'm still a bit baffled when it comes to getting better depth of field. For example, though I've messed with aperture settings in the M mode, I'm still not getting the depth I want when doing close-ups of figurines, etc.

In this photo a distance of only 1 inch from the deer's eyes to his nose yields a blurred nose when I had manually focused on the eyes. I realize this isn't a major issue, but the better the overall focus the better for sales, I believe. Is it a settings issue? Is it a lens issue? Is it just normal? Any ideas?

Thanks!

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E

Eye-level

Banned
Two words sir...

Reversing ring.

They make one for the 18-55 kit lens...get one and learn to use the lens with it and you will achieve the results you are after.
And you are right...they need to be in focus if you are trying to sell product.
 
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W

WhiteLight

Senior Member
DOF depends on a few factors, specially if you are not using a prime lens.
First, you need to be as close as possible to the subject
Second, the lens must be at the longest focal length - for the 18-55, best DOF can be achieved at 55mm
Third, the background must be at least 6-8 feet behind the subject.
Last & most importantly, you must at the lowest possible f number like 3.5 in the 18-55 or 1.8 in most prime lenses.

Regarding the pic you posted, there is nothing wrong with it.
Since you focused on the eyes, the nose is going to be blurred.
Think of where the eyes are as a sheet of paper & keep placing more sheets till you reach the nose.
Lots of sheets of paper in between eh?
That shows each of them are in different focus planes, hence the blurry nose & clear eyes
 
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J

JA Warrior

New member
Hey Eye-level! I was told to do just that in another thread about close-ups. Will that yield better depth of field, or just closer close-ups - or both?
 
J

JA Warrior

New member
WhiteLight said:
Regarding the pic you posted, there is nothing wrong with it.
Since you focused on the eyes, the nose is going to be blurred.
Click to expand...

So, are you saying that the amount of blur on the nose is to be expected even with careful aperture setting adjustment? To be precise, I was at a distance of about 12 inches from the 18-55 lens to the figurine.
 
D

Don Kuykendall_RIP

RIP :(
Also remember that you are not going to be able to get everything in focus when the object is small and you are close to it. If you shoot F22 and you are at the limit for the 18-55 55MM you can focus at about 1 foot. You can see here that you do not have much room at best

Capture.JPG

As you can see only .07th of a foot will be in focus.

You can see this calculator at Online Depth of Field Calculator
 
D

Don Kuykendall_RIP

RIP :(
WhiteLight said:
DOF depends on a few factors, specially if you are not using a prime lens.
First, you need to be as close as possible to the subject
Second, the lens must be at the longest focal length - for the 18-55, best DOF can be achieved at 55mm
Third, the background must be at least 6-8 feet behind the subject.
Last & most importantly, you must at the lowest possible f number like 3.5 in the 18-55 or 1.8 in most prime lenses.

Regarding the pic you posted, there is nothing wrong with it.
Since you focused on the eyes, the nose is going to be blurred.
Think of where the eyes are as a sheet of paper & keep placing more sheets till you reach the nose.
Lots of sheets of paper in between eh?
That shows each of them are in different focus planes, hence the blurry nose & clear eyes
Click to expand...

He is trying to get MORE DOF so he needs a higher number like F22
 
E

Eye-level

Banned
Reversing ring will allow you to more accurately produce it life size. (Remember this is a small figurine we are talking about not a full size animal..haha) 1" is WAY past close focus for the 18-55...and all other lenses too for that matter except specialty stuff. eg macro 1:1 (28/2.8 AIS is closest focusing Nikkor made and it is about 8 inches I think)

Will it make your whole image in focus? I don't know but I bet it will be better than what you have.

F22 is to extreme in my books but I do believe that F8 or even F11 is necessary for stuff like this...BUT I have no idea really haven't done any product photos except shooting my cameras in which case I use the 105 and stand 3 feet or so back...talk about DOF at F8! :)
 
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D

Don Kuykendall_RIP

RIP :(
JA Warrior said:
Hey Eye-level! I was told to do just that in another thread about close-ups. Will that yield better depth of field, or just closer close-ups - or both?
Click to expand...

If I am not mistaken it will just give you better close ups. But remember, the closer you are the less DOF you will have. Less in focus.

Small objects= closer to camera = less DOF

There is one thing you might want to learn and that is Focus Stacking. Not easy but it will give you the exact results you are looking for.

One quick thing to do it to back up to about 3.5 feet or so and you can get about 12 inches total in focus. Then just crop to the size you want.

I am assuming the object is about a foot from front to back.

If is is say 6 inches then move the camera to about 2.5 feet away and all will be in focus.

Just use the DOF Calculator to see where on the object to focus. In the last example (2.5 feet) you would have

Subject distance 2.5 ft

Depth of field
Near limit 2.26 ft
Far limit 2.8 ft
Total 0.53 ft
In front of subject 0.24 ft (45%)
Behind subject 0.3 ft (55%)
 
D

Don Kuykendall_RIP

RIP :(
Eye-level said:
The best solution IMO is a macro lens. Right tool for the job.
Click to expand...

That would still only get him closer which would only give him less depth of field. He has the same camera and lens that I do. The close focus for the kit lens is 11 inches at 55.. He said in one post he was shooting at about a foot and he is getting the entire head in the shot. He is not going to be able to get the DOF he needs shooting this close. Going to have to back up and then crop. If he gets really good lighting, using ISO 100 and focus properly the crop should not be noticeable with the D5100. Especially with product photography. That would never be printed over 8x10 MAX.

This gets him what he wants and does not cost him any money. You should appreciate that If I remember some of your posts. :)
 
W

WhiteLight

Senior Member
JA Warrior said:
So, are you saying that the amount of blur on the nose is to be expected even with careful aperture setting adjustment? To be precise, I was at a distance of about 12 inches from the 18-55 lens to the figurine.
Click to expand...

Yes, it is to be expected definitely.
Shoot the same subject at the same distance, with varying apertures - f9, f11 and f22..
You will find the nose getting clearer & clearest at at f22.

Also if you move away from the subject, the DOF won't be as shallow as when you are upclose.

Try both of the above out, you'll understand better.

Tracsoft - Don Kuykendall said:
He is trying to get MORE DOF so he needs a higher number like F22
Click to expand...

Right :)
I was explaining the meaning of DOF & how shallow DOF is obtained & why he was seeing the blurry nose.
That's what i meant to convey in the second bit of the post..

Apologies if i caused any confusion!
Thanks for pointing that Don
 
D

Don Kuykendall_RIP

RIP :(
I think we are saying the same thing but I just don't want to confuse the OP

The closer you are to the subject the Less DOF you have
The further away you are from the subject the More DOF you have

Go to Online Depth of Field Calculator and play with the different numbers. That will show you how distance, Aperture and focal length can change the DOF you are getting. Play with only one at the time and watch the numbers. Greater distance and lower Aperture can give you the same DOF as less distance and larger Aperture. Then we get into perspective which is what makes your nose look really big when someone puts a camera right in your face and shoots.

​
 
E

Eye-level

Banned
18mm the wide end is the end to shoot from not 55 because a wider focal length always gives you more DOF.

Check the DOF calculator and you will see that 18 at f22 gives you .95 in focus...that is a lot for small product...I would stop it down once or twice myself.

The most important thing though is you probably really need a tripod if you aren't using one already.
​
 
D

Don Kuykendall_RIP

RIP :(
Eye-level said:
18mm the wide end is the end to shoot from not 55 because a wider focal length always gives you more DOF.

Check the DOF calculator and you will see that 18 at f22 gives you .95 in focus...that is a lot for small product...I would stop it down once or twice myself.

The most important thing though is you probably really need a tripod if you aren't using one already.
​
Click to expand...

Going to 18 will give you more depth of field would do the same thing as moving the camera back. Either way he is going to have to shoot wide and crop. He never said what MM he was shooting at just that he was a foot away. The optics just won't do what he wants. All in Focus and full frame. The only free and easy way to do it is to back up or be a 18mm and then crop to get the framing the way he needs it. The D5100 can handle that as long as his exposure is good.
 
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