Need a little focus help (pic included)

[ScottL4619]

I am getting a little better at taking pictures, but as you can see in the photo below, I'm having trouble getting the whole shroom in focus.

I have a Nikon Coolpix 5000 that is a few years old, but still works great. I have the ability to change all of the settings on the camera manually, but still cannot get it quite right. At the next focus distance, the back of the shroom is in focus, but the front is blury. And at the the focus distance in this picture (next click down) the front is in focus, but the back is blurry. Any suggestions??

 

[BlueCorn]

What you're dealing with is called depth or field or DOF. The wider the aperture (lens opening) the smaller the f/stop number and the shallower the DOF. To get more of the mushroom in focus you need to use a higher f/stop number. You might need to switch to aperture priority mode on your camera to do so.

 

[ScottL4619]

Is there generally an f/stop setting, or do I need to change the ISO to make the f/stop higher? Or am I confusing two things that aren't related? Thanks for your help, this camera stuff is tricky.

 

[BlueCorn]

It's all related. Exposure is like a triangle. The sides are ISO, exposure time and aperture.

If you use a higher f/stop you need to either increase ISO or exposure time to get the same amount of light into the camera. Finding the right aperture setting for a given scene can often be trial and error. If you're using a SLR many have a depth of field preview button so that you can see what is, or isn't, in focus. On your coolpix you'll have to experiment.

Cheers

 

[ScottL4619]

Nevermind, I found that there is an f/stop setting on my camera. What do you think a good setting is for it? It is on 2.8 now. I'm not sure what units that is in or how the number correspond.

 

[BlueCorn]

The higher the number, the smaller the opening, the greater the DOF.

 

[ScottL4619]

<a href=showthread.php?s=&postid=11142030#post11142030 target=_blank>Originally posted</a> by beerguy
It's all related. Exposure is like a triangle. The sides are ISO, exposure time and aperture.

If you use a higher f/stop you need to either increase ISO or exposure time to get the same amount of light into the camera. Finding the right aperture setting for a given scene can often be trial and error. If you're using a SLR many have a depth of field preview button so that you can see what is, or isn't, in focus. On your coolpix you'll have to experiment.

Cheers

Yes, trial and error seems to be the key. I take about 100 pictures to get 10 good ones. Do most people turn pumps off to get good pictures? Thanks for your help, I'll experiment with the f/stop tonight.

 

[jwedehase]

<a href=showthread.php?s=&postid=11142032#post11142032 target=_blank>Originally posted</a> by ScottL4619
Nevermind, I found that there is an f/stop setting on my camera. What do you think a good setting is for it? It is on 2.8 now. I'm not sure what units that is in or how the number correspond.

That number is the denominator (bottom number) in a fraction. The fraction represents a fraction of an inch. At f/2.8, your lens aperture is opened 1/2.8". The decimal creates some confusion, so another example is that F/4 is open 1/4", and f/10 is 1/10". As you can see, the higher the F number, the smaller the opening. However, the smaller the opening, the longer you need to keep the shutter open, but it comes with greater DOF.

 

[ScottL4619]

<a href=showthread.php?s=&postid=11144708#post11144708 target=_blank>Originally posted</a> by jwedehase
That number is the denominator (bottom number) in a fraction. The fraction represents a fraction of an inch. At f/2.8, your lens aperture is opened 1/2.8". The decimal creates some confusion, so another example is that F/4 is open 1/4", and f/10 is 1/10". As you can see, the higher the F number, the smaller the opening. However, the smaller the opening, the longer you need to keep the shutter open, but it comes with greater DOF.

Makes perfect sense; even with the decimal. Thank you for your help!

 

[PJSEA]

To get the best pictures, make sure the water is the clearest you can get it. Clean the glass and stop all flow and let things settle before you take pictures.

 

[ConGi]

Nice coral