Depth of Field question

[jmig]

In going through my 1000 or so shots of my vacation, I noticed that I took a lot of flowers. In some of the shots the flower I focused on is fine but ones a few inches or feet away are out of focus. This made the shot look bad to me, unless I crop everything else out.

In my old SLR cameras I could check the depth of field before shooting. the Nikon D-40 doesn't have this feature. Is there anyway I can check the DoF in the D-40? Or do I have to either memorize the DoF of each F stop OR :d purchase a D-90 body which does allow this?

[Kiwikat]

You've pretty much got to get used to which aperture renders how much in focus. I'd suggest you go out and find a flower or a small prairie or something with a lot of detail and take a shot at each aperture setting. That should help you get used to the DOF. Shooting on Av mode will get you accustomed to DOF in no time.

To get both a flower and the background in focus you're going to need to be shooting at at least f/11-f/16. You will then most likely need a tripod. It also runs the risk of making everything blurry from wind as your shutter speed will be quite slow to compensate for the small aperture (large f/ number).


I'm not sure if the D40 has a depth of field preview button. I know the XSi does, but I rarely use it. I think it is best to learn how aperture values affect your photo, rather than to rely on a button on your camera to check it for you.

[Panther_99FS]

jmig,
You'll just have to go back to shooting film with your old SLRs....

In all seriousness though, I've seen in another forum that in Bryan Peterson's "Understanding Exposure" book he states a "poor man's" solution to a DOF preview button..

"while looking through the viewfinder at your target shot, if you turn the lens one quarter of a turn (as if removing it from the body), this will allow you to see the actual depth-of-field that the chosen aperture will render. This will allow you to make adjustments until you have the DOF you want – just as a DOF preview button would do. "

I've never tried this though.....The below website has helped me out a bit but I'm the first to admit that I'm no DOF expert......http://www.cambridgeincolour.com/tut...h-of-field.htm

And finally, if all else fails, get a D300s or D90 :d

[Panther_99FS]

I think it is best to learn how aperture values affect your photo, rather than to rely on a button on your camera to check it for you.

Then why would so many manufacturers put the button on :ques: Especially on their professional cameras :ques: And then, some folks actually want the button

[Kiwikat]

Then why would so many manufacturers put the button on :ques: Especially on their professional cameras :ques: And then, some folks actually want the button

Probably the same reason some professional cameras include a "green box" mode...

The 1D Mark IV comes to mind...

[JorisVandenBerghe]

Sony users are the true professionals ...unless you buy an A700, A850 or A900, you won't have a DoF preview button. That said, the excellent live view on the lower-end models certainly makes up for that!

John, I suggest getting accustomed to aperture values. William's right, the only thing he forgot is that you're using a Nikon, which doesn't have an Av-mode but an A-mode .

Not a DoF expert either...understand the basics and know that the DoF becomes smaller upon focusing closer, but that's about it...hyperfocal distance, circle of confusion ? Don't ask me....

Don't think most people, even professionals, actually care about things like this. If they can get it right in the picture, it's ok.

[Panther_99FS]

Sony users are the true professionals ...unless you buy an A700, A850 or A900, you won't have a DoF preview button. .

Which are arguably Sony's "Professional" grade cameras

[JorisVandenBerghe]

Voilà...the users of the lowest-end models are the best photographers, they don't need a DoF-preview button, contrary to those high-end geeks ...:

[will_b]

Is there anyway I can check the DoF in the D-40? Or do I have to either memorize the DoF of each F stop OR :d purchase a D-90 body which does allow this?

If you've got a smart phone take a look in the app store, there's several caluclators available for the iPhone/iPod touch for just a few $'s.

I'm sure the other phones Droid etc. will have their own versions.

[jmig]

If you've got a smart phone take a look in the app store, there's several caluclators available for the iPhone/iPod touch for just a few $'s.

I'm sure the other phones Droid etc. will have their own versions.

Thanks Will! I am a CrackBerry. I was reading through the manual/guide I purchased from Thom Hogan when I bought the D-40. It has an Excel spreadsheet on DoF for all the lenses.

I need to study it and do what Kat suggested. Take a bunch of shots at different F stops and compare the results.

[Moparmike]

Interesting...I didn't realize that the DoF preview wasn't standard equipment on many DSLRs until I read this post. (I tend to stick in my little Pentax world... )

It's a standard on all the Pentax DSLRs...and if you're hooked on old glass like I am, it's a real quick way to meter old "non-A" (the Pentax guys will know what a non-A is) or M42 screw-mount lenses.
I also like to shoot close-up shots with a lot of bokeh so it's something I fiddle with quite a bit.

It's also a lazy-man's way of not having to remember the old math rules needed to calculate DoF.
Once you get used to a particular lens (and after many shots at different apertures like Kiwi suggests) you'll get to know better what f-stop to grab for the particular shot you're taking. The nice thing about digital...and it's also a stinker for making you lazy...is if you've got a stationary subject, you can always "chimp" the shot and reshoot with different settings if it didn't turn out the way you wanted it. :d


BTW, if you're looking for just general "everything in focus" type of shots outdoors, the good ole "sunny 16" rule still applies to digital just like film. Sunny? f/16 A bit of light overcast? Open up a stop to f/11. More overcast? Open up another stop.

[Kiwikat]

BTW, if you're looking for just general "everything in focus" type of shots outdoors, the good ole "sunny 16" rule still applies to digital just like film. Sunny? f/16 A bit of light overcast? Open up a stop to f/11. More overcast? Open up another stop.

I find sunny 16 to be a bit odd considering most lenses are affected by diffraction starting at f/11. You lose sharpness fast after f/11...

f/8 is my go-to aperture outdoors. Though I usually shoot my 300mm at f/5.6 or 6.3.

[JorisVandenBerghe]

Kiwi is right...and the smaller the sensor (actually the higher the pixel-density), the faster diffraction will influence the resolution of the image. Olympus and Panasonic cameras for instance, start to show the effects of diffraction from f/8, as their sensor is twice as small as a full-frame/35mm camera. Nikon and Sony sensors (let's just say Sony sensors, they are the same anyway, except for the D700/D3/D3S ...) are 1.5 times smaller, Canon's sensors are fractionally smaller with a 1.6 crop factor (actually I believe it's something like 1.52/54 vs 1.58/57).

That said, a lot of depends on the lens and its sharpness. This is an example I always give when talking about diffraction: a Spit, landing at Duxford. The sun had already set quite a bit (late afternoon), so there was a lot of light at the angle I was pointing it to the Spitfire...and at 1/250, you don't need that much light - the ISO was set to 200. At 280mm (more to the end of the range, since it's a 70-400G SSM I have used there) and f/14, the image was perfectly sharp...with problems whatsoever.

http://www.flickr.com/photos/vdbj/41...57622766151521

So it's not just about the camera/sensor, but a lot of depends on the optical properties of the lens you use.

[roger-wilco-66]

So it's not just about the camera/sensor, but a lot of depends on the optical properties of the lens you use.

I second that. It's good to know the MTF curve of your lens, and even better when the camera knows it too (my trusty Pentax has a special MTF operation mode).


Cheers,
Mark

[Moparmike]

That said, a lot of depends on the lens and its sharpness. This is an example I always give when talking about diffraction: a Spit, landing at Duxford. The sun had already set quite a bit (late afternoon), so there was a lot of light at the angle I was pointing it to the Spitfire...and at 1/250, you don't need that much light - the ISO was set to 200. At 280mm (more to the end of the range, since it's a 70-400G SSM I have used there) and f/14, the image was perfectly sharp...with problems whatsoever.

http://www.flickr.com/photos/vdbj/41...57622766151521

So it's not just about the camera/sensor, but a lot of depends on the optical properties of the lens you use.

I'll agree that as the sensor shrinks below that 135mm "standard" that a lot of the old rules are based around then things will differ a bit. I've not noticed that it's enough to deviate from...at least shooting with a 6.1MP APS-C sensor.

I do agree with Joris that sharpness is still more a factor of the quality of the glass your using in front of the sensor more than the sensor itself.