Trouble focusing

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Stefani

New member
I am a novice photographer and have been volunteering at the animal shelter taking pictures of the cats for their website. I have been having trouble getting the cats in focus, probably 1 out of every 20 photos will be in focus. I am using a Nikon D3100 with a Nikkor 50mm lens. I am photographing in pretty poor light, I believe it is florescent light. I have the ISO set to 800 and normally shoot with the aperture as open as it will go. and I am using the auto AF. Does anyone have any recommendations of what settings to use? or pointers on the best way to photograph cats? I would love some advice.
Thanks,
Stefani
 
BackdoorArts

BackdoorArts

Senior Member
Post some examples with the EXIF data intact. When you say you're in "poor light" I suspect some of your "out of focus" may also be movement.
 
S

Stefani

New member
BackdoorHippie said:
Post some examples with the EXIF data intact. When you say you're in "poor light" I suspect some of your "out of focus" may also be movement.
Click to expand...

Here is an example.

DSC_0016.jpg

And here is all the EXIF data.

Camera:Nikon D3100
Lens:AF-S Nikkor 50mm f/1.8G
Shot at 50 mm
Exposure:Auto exposure, Not Defined, [SUP]1[/SUP]/60 sec, f/2.2, ISO 400
Flash:Off, Did not fire
Focus:AF-A, at 75cm, with a depth of field of about 1.8cm, centered on the focus point
AF Area Mode: Auto-area
Date:September 13, 2015 1:37:39PM (timezone not specified)
(5 days, 23 hours, 43 minutes, 56 seconds ago, assuming image timezone of 7 hours behind GMT)
Time Zone Offset:-07:00
File:4,608 × 3,072 JPEG (14.2 megapixels)
3,023,323 bytes (2.9 megabytes)
 
D

Don Kuykendall_RIP

RIP :(
If you re shooting "Wide open" which I assume is f1.8 then you have very shallow Depth of Field. This is not going to help your focus. Also with that lens you should be shooting at least 1/80 sec at a minimum.

The reciprocal rule is that the shutter speed of your camera should be at least the reciprocal of the effective focal length of the lens. Since you are shooting a crop sensor lens you have to multiply the focal length of your lens (50) time the crop factor (1.5) so that equals 75. so you should be shooting at east 1/75 a second or as close to that as possible.

Depending on your skill in shooting then you might be able to go slower but with moving cats I really would try to follow this guideline. Ideal shooting would be to set the camera on f8 at 1/80 (or as close as possible) With the D3100 you are smart to keep it a ISO 800 since noise becomes a factor any higher than that. Your best bet it to get a flash that you can bounce off the ceiling so you can get more light.
 
Fred Kingston

Fred Kingston

Senior Member
Why not just use the camera's flash? 1/60 is your basic problem, and shooting wide-open limits your depth of field...further limiting your ability to get a sharp focus...
 
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weebee

Senior Member
I would get the shutter speed up some. And use flash. Instead of auto focus try single point focus and focus on the cats head. And use AF-C. That way when the shutter button is depressed half way. You'll still be adjusting the focus. Page 55 in your manual will point this out. Higher shutter normally means less chance of blur. But it will not correct out of focus issues. What 50mm lenses do you have exactly?
 
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weebee

Senior Member
Stefani said:
These are skittish pound cats so the flash would really freak them out even more.
Click to expand...

Then you may have to bump up the ISO. And clean it up as best as you can later. Can you increase the lighting with other lights? I've used portable stand lights in the past for these things.
 
Bob Blaylock

Bob Blaylock

Senior Member
Stefani said:
Here is an example.

View attachment 179894

And here is all the EXIF data.

Camera:Nikon D3100
Lens:AF-S Nikkor 50mm f/1.8G
Shot at 50 mm
Exposure:Auto exposure, Not Defined, [SUP]1[/SUP]/60 sec, f/2.2, ISO 400
Flash:Off, Did not fire
Focus:AF-A, at 75cm, with a depth of field of about 1.8cm, centered on the focus point
AF Area Mode: Auto-area
Date:September 13, 2015 1:37:39PM (timezone not specified)
(5 days, 23 hours, 43 minutes, 56 seconds ago, assuming image timezone of 7 hours behind GMT)
Time Zone Offset:-07:00
File:4,608 × 3,072 JPEG (14.2 megapixels)
3,023,323 bytes (2.9 megabytes)
Click to expand...


Here's where your camera focused.

DSC_0016a.jpg

Stefani said:
And here is all the EXIF data.

Focus:AF-A, at 75cm, with a depth of field of about 1.8cm, centered on the focus point
AF Area Mode: Auto-area
Click to expand...

And there, I think, is your problem. You're using Auto-area mode, in which the camera tries to decide what you want it to focus on, and in this case, it chose foolishly. I suggest that you set it to single-point focus mode, and make sure that point is on the cat's face when you shoot.
 
Bob Blaylock

Bob Blaylock

Senior Member
Don Kuykendall said:
If you re shooting "Wide open" which I assume is f1.8 then you have very shallow Depth of Field. This is not going to help your focus. Also with that lens you should be shooting at least 1/80 sec at a minimum.

The reciprocal rule is that the shutter speed of your camera should be at least the reciprocal of the effective focal length of the lens. Since you are shooting a crop sensor lens you have to multiply the focal length of your lens (50) time the crop factor (1.5) so that equals 75. so you should be shooting at east 1/75 a second or as close to that as possible.

Depending on your skill in shooting then you might be able to go slower but with moving cats I really would try to follow this guideline. Ideal shooting would be to set the camera on f8 at 1/80 (or as close as possible) With the D3100 you are smart to keep it a ISO 800 since noise becomes a factor any higher than that. Your best bet it to get a flash that you can bounce off the ceiling so you can get more light.
Click to expand...

I wonder if the lens that she's using has VR.

I'm not seeing any sign of motion blur in her pictures, just bad focusing. Where you can find an area that is in focus, that area is nice and sharp. I'd say that she could get away with a slower shutter speed than she's using, if she thought she needed to in order to close the lens down a bit for more depth of field.

I think the whole of her problem is that her camera is picking the wrong thing on which to focus.
 
Marcel

Marcel

Happily retired
Staff member
Super Mod
You might have more success rate if you would use AF-S, this is using a single focus point, aiming the focus point to the cat's closest eye, half pressing the shutter to lock focus and then quickly re-framing your shot. Try give this technique a shot and you should see better results. Also, since your pictures probably won't end up in poster sizes, don't be afraid to use higher ISO (up to 1600) to get a faster shutter speed, and finally, maybe close the lens a stop or two to have a bit more depth of field.

You can also get a cheap led flashlight that could be very beneficial.

Remember that practice makes perfect.
 
Dawg Pics

Dawg Pics

Senior Member
Is there any reason you can't set-up a secondary light source? A cheap work-light maybe?

I don't know if you have a helper, but you can get somebody to help get the kitty's attention with one of those fuzzy things on a string. Looks like a fishing pole.
 
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skater

New member
I definitely wouldn't use the flash - you'll get green-eye, the feline equivalent of red-eye, and who wants to adopt a monster cat? You could do it with bounce flash if you have an external flash, but I wouldn't even bother with the internal flash.

I'm glad to see you are doing this - unfortunately shelters often have terrible pictures of the cats and dogs. :( (We have two cats from shelters.)
 
A

aroy

Senior Member
Use
. Single point focus, focus on the eyes
. AFC, for continuous focusing. Avoid Automatic focus selection as it will invariably focus where you do not want to.
. Matrix metering
. Aperture priority
. ISO 100, with D3100 I would not go beyond 400 and that too if absolutely necessary
. Try a few aperture values starting with F1.8 going upto F4 without flash, and F8 with flash.

If you can get hold of an external flash, then use it with the head pointed up and exposure compensation +2EV. That will brighten up your scene and give yo sharper images.
 
R

RobV

Senior Member
No one has mentioned the "Pet" setting in "Scenes", or does the D3100 not have this feature?
My D5200 has it, and I have had very good success taking pictures of my cats.
I am at work right now, so I cannot share.

Edit: just looked at the owners manual for the D3100. I guess it does not have anything for Pets.
 
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RobV

Senior Member
This is one of my cats photographed with my new 35mm 1.8 lens. Set on Scenes, Pets, which is pretty much auto. (D5200).

_DSC0584.jpg
 
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