DOF help

trishytee · 05-04-2016, 10:47 AM

I am wondering how I can get all these egrets (well, not these actual ones) in focus. I had f13 and was using the 500mm end of the lens. I thought with the larger f stop I would manage a better depth of field.
Any advice welcome.

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loco · 05-04-2016, 11:00 AM

Try this online DOF calculator. Not sure how far away you were but at 500mm, you're not going to get much DOF even at f/16.

Online Depth of Field Calculator

**marcusBMG** · 05-04-2016, 11:11 AM

There are numerous dept of field calculators online like this one:

A Flexible Depth of Field Calculator

but basically you are only going to get one bird in focus at 500mm, unless they are coincidentally both in the plane of focus.
PS Cambridge in Colour is very good web site

**UncleVanya** · 05-04-2016, 11:13 AM

Answer: Get closer, use shorter focal length. Switch to an 8x10 camera and crop... etc. If you are really good maybe you could focus stack but the birds would have to sit still which they aren't good at.

Physics stinks sometimes.

desertscape · 05-04-2016, 11:41 AM

Sometimes you have to stop the lens down further and forget about diffraction. Focus between the nearest and furthest bird and stop to f/22 or more if necessary. The ISO may need to be boosted if the birds are moving.

Na Horuk · 05-04-2016, 11:56 AM

Originally posted by desertscape

Sometimes you have to stop the lens down further and forget about diffraction. Focus between the nearest and furthest bird and stop to f/22 or more if necessary. The ISO may need to be boosted if the birds are moving.

Yeah, this, with a lot of digital sharpening afterward. And possibly cropping in post (keeps the same DoF, but appears to increase magnification; but it reduces resolution).

Originally posted by UncleVanya

Answer: Get closer, use shorter focal length.

Originally posted by UncleVanya

If you are really good maybe you could focus stack but the birds would have to sit still which they aren't good at.

These are also fine choices. Trying to align yourself so that birds are in the focus plane is another technique, but terrain can often prevent that.
If you have a sturdy tripod you can switch AF points really fast and get two shots of the birds, and then digitally blend the photos for maximum DoF. Of course, animals are not the best subject for this technique.

Finally, If you have a 500mm lens, there is only so much DoF you can expect. Its optics. Good luck. And the OP shot is already pretty good

JeffB · 05-04-2016, 12:31 PM - **1 Like**

Looks like you were focused on the nearest bird to you. You can make better use of your limited hyper focal distance with the 500mm lens. Based on the image above I'm guessing you were ~50m from the subjects. That would give you a hyper focal distance of about 1m from near to close sharpness. It looks like your nearest and farthest birds were a bit more than 1 meter apart relative to you. If you focus on the middle subject (relative to camera distance - that would be left most bird above) you would have a better chance of getting the nearer and further subjects in better focus too.

C_Jones · 05-04-2016, 12:50 PM - **1 Like**

If you went to 400 mm, focused on the most common area among the subjects, and tested with F13 and other apertures which you like to get the best result, you may end up with a nice croppable image which allows reasonable detail if you include all of the subjects across the field of view. A reasonably similar position/distance on the focus plane of the subjects is going to possibly give you the best results, but that may not always be the circumstances.

**lsimpkins** · 05-04-2016, 02:52 PM

Originally posted by loco

Try this online DOF calculator. Not sure how far away you were but at 500mm, you're not going to get much DOF even at f/16.

Online Depth of Field Calculator

DoF Calc is a good Android phone ap (not sure if they have an iPhone version). If the shot was taken from 100' away, depth of field would have only been 3' on either side of the plane of focus. Even f/22 would only get you a little more than 5'. At 50' distance, f/13 would not even give a foot of focus depth on either side of the plane of focus.

The suggestions regarding shooting with smaller aperture and with shorter focal length, then cropping will give improved DoF results, but this is a difficult shot.

**Bruce Clark** · 05-04-2016, 09:14 PM

As others have said, DoF is quite shallow at 500mm. AT 50 feet the total Dof is approx 1.5 feet, At f16 it is approx 1.9 ft at f22 it is approx 2.7 ft. It is difficult to judge the distance from the camera to subject and also the spacing between the three birds from the the photo. It seems to me that the front bird is in good focus. the middle bird is almost acceptable and the rear bird nowhere near it. It also appears to me that a fair amount of ground in front of the first bird is in focus. This suggests to me the focus was on the first bird resulting in a distance before and behind it to be in good focus. If focus had been on the centre bird your total depth of field may just have covered the three birds. I say may because without the knowledge of the distances it is not really possible to calculate.It is all a bit of guess work as we are never going to be able to trot out there with a tape measure.

in summary,
Use smallest possible aperture f16-f22 and accept the diffraction and also noise from higher ISO
Focus on a point in the middle of the scene to make the maximum use of your available DoF
If it still does not fit, wait for the birds to align themselves a bit better. It might never happen but if it does, magic.

**clackers** · 05-04-2016, 09:24 PM

Originally posted by UncleVanya

Answer: Get closer.

If you get closer, the DoF is reduced.

**UncleVanya** · 05-04-2016, 09:42 PM

Originally posted by clackers

If you get closer, the DoF is reduced.

", use shorter focal length." the two are part of single answer. Using a shorter focal length will reduce image size and require that the person be closer but the shorter focal length can improve DOF depending on the amount of change. Not sure if you can still get close enough and not spook the birds but that's my intention. Did I make a mistake?

**clackers** · 05-04-2016, 09:50 PM

Originally posted by UncleVanya

", use shorter focal length." the two are part of single answer. Using a shorter focal length will reduce image size and require that the person be closer but the shorter focal length can improve DOF depending on the amount of change. Not sure if you can still get close enough and not spook the birds but that's my intention. Did I make a mistake?

Well, using a shorter focal length but then standing closer counter each other.

JeffB nailed it, I reckon. Focus on the bird in the middle for starters, maybe it's not necessary to go to f16. If the AF picked out that bird because it was nearer, just override its decision.

trishytee · 05-04-2016, 10:23 PM - **1 Like**

Thanks everyone. I looked through my files and found an image I took of pelicans. I was on the opposite bank so quite a fair way from them. They are all nice and sharp, and seems as if all the above is correct. This was taken at 440mm at f8 ISO 800 1/1250.I have cropped to take out some of the bank they were on, plus a little sharpening. So I must learn to step back a little and trust the cropping!
Thanks again for taking the time to reply.

Na Horuk · 05-05-2016, 07:27 AM

Great shot!
There are also some specialized sharpening tools (plugins, standalone programs) that are decent. Topaz has some of these things and is partnered with the forum here, or you can try the (now free) Nik Effects from Google, which also has some sharpening tools. Yes, it can make the workflow a little longer and most of these (all?) force you to work with tiff instead of dng (and tiff take much more space), but they can give you good results. It can be worth it for some special photos.
You do cropping and rotating first, then NR, then presharpening, all the PP, and then the output sharpening. Especially if you do prints, sharpening is important

05-04-2016, 09:50 PM	#13
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by UncleVanya ", use shorter focal length." the two are part of single answer. Using a shorter focal length will reduce image size and require that the person be closer but the shorter focal length can improve DOF depending on the amount of change. Not sure if you can still get close enough and not spook the birds but that's my intention. Did I make a mistake? Well, using a shorter focal length but then standing closer counter each other. JeffB nailed it, I reckon. Focus on the bird in the middle for starters, maybe it's not necessary to go to f16. If the AF picked out that bird because it was nearer, just override its decision. Last edited by clackers; 05-04-2016 at 09:57 PM.

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05-04-2016, 11:00 AM	#2
loco Veteran Member Join Date: Mar 2011 Location: Virginia Photos: Gallery \| Albums Posts: 2,846	Try this online DOF calculator. Not sure how far away you were but at 500mm, you're not going to get much DOF even at f/16. Online Depth of Field Calculator

05-04-2016, 11:11 AM	#3
marcusBMG Site Supporter Join Date: Nov 2012 Location: North Wales Photos: Gallery \| Albums Posts: 2,869	There are numerous dept of field calculators online like this one: A Flexible Depth of Field Calculator but basically you are only going to get one bird in focus at 500mm, unless they are coincidentally both in the plane of focus. PS Cambridge in Colour is very good web site

05-04-2016, 11:13 AM	#4
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,446	Answer: Get closer, use shorter focal length. Switch to an 8x10 camera and crop... etc. If you are really good maybe you could focus stack but the birds would have to sit still which they aren't good at. Physics stinks sometimes.

05-04-2016, 11:41 AM	#5
desertscape Pentaxian Join Date: Feb 2009 Location: Arizona Posts: 1,272	Sometimes you have to stop the lens down further and forget about diffraction. Focus between the nearest and furthest bird and stop to f/22 or more if necessary. The ISO may need to be boosted if the birds are moving.

05-04-2016, 11:56 AM	#6
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Originally posted by desertscape Sometimes you have to stop the lens down further and forget about diffraction. Focus between the nearest and furthest bird and stop to f/22 or more if necessary. The ISO may need to be boosted if the birds are moving. Yeah, this, with a lot of digital sharpening afterward. And possibly cropping in post (keeps the same DoF, but appears to increase magnification; but it reduces resolution). Originally posted by UncleVanya Answer: Get closer, use shorter focal length. Originally posted by UncleVanya If you are really good maybe you could focus stack but the birds would have to sit still which they aren't good at. These are also fine choices. Trying to align yourself so that birds are in the focus plane is another technique, but terrain can often prevent that. If you have a sturdy tripod you can switch AF points really fast and get two shots of the birds, and then digitally blend the photos for maximum DoF. Of course, animals are not the best subject for this technique. Finally, If you have a 500mm lens, there is only so much DoF you can expect. Its optics. Good luck. And the OP shot is already pretty good

05-04-2016, 12:31 PM - 1 Like	#7
JeffB Senior Member Join Date: Nov 2009 Location: 'Merica! Posts: 209	Looks like you were focused on the nearest bird to you. You can make better use of your limited hyper focal distance with the 500mm lens. Based on the image above I'm guessing you were ~50m from the subjects. That would give you a hyper focal distance of about 1m from near to close sharpness. It looks like your nearest and farthest birds were a bit more than 1 meter apart relative to you. If you focus on the middle subject (relative to camera distance - that would be left most bird above) you would have a better chance of getting the nearer and further subjects in better focus too.

05-04-2016, 12:50 PM - 1 Like	#8
C_Jones Pentaxian Join Date: Sep 2012 Location: NY Photos: Gallery \| Albums Posts: 6,077	If you went to 400 mm, focused on the most common area among the subjects, and tested with F13 and other apertures which you like to get the best result, you may end up with a nice croppable image which allows reasonable detail if you include all of the subjects across the field of view. A reasonably similar position/distance on the focus plane of the subjects is going to possibly give you the best results, but that may not always be the circumstances.

05-04-2016, 02:52 PM	#9
lsimpkins Site Supporter Join Date: Feb 2013 Location: SE Pennsylvania Photos: Gallery \| Albums Posts: 537	Originally posted by loco Try this online DOF calculator. Not sure how far away you were but at 500mm, you're not going to get much DOF even at f/16. Online Depth of Field Calculator DoF Calc is a good Android phone ap (not sure if they have an iPhone version). If the shot was taken from 100' away, depth of field would have only been 3' on either side of the plane of focus. Even f/22 would only get you a little more than 5'. At 50' distance, f/13 would not even give a foot of focus depth on either side of the plane of focus. The suggestions regarding shooting with smaller aperture and with shorter focal length, then cropping will give improved DoF results, but this is a difficult shot.

05-04-2016, 09:14 PM	#10
Bruce Clark Loyal Site Supporter Join Date: Mar 2010 Location: Ocean Grove, Victoria Photos: Gallery \| Albums Posts: 4,458	As others have said, DoF is quite shallow at 500mm. AT 50 feet the total Dof is approx 1.5 feet, At f16 it is approx 1.9 ft at f22 it is approx 2.7 ft. It is difficult to judge the distance from the camera to subject and also the spacing between the three birds from the the photo. It seems to me that the front bird is in good focus. the middle bird is almost acceptable and the rear bird nowhere near it. It also appears to me that a fair amount of ground in front of the first bird is in focus. This suggests to me the focus was on the first bird resulting in a distance before and behind it to be in good focus. If focus had been on the centre bird your total depth of field may just have covered the three birds. I say may because without the knowledge of the distances it is not really possible to calculate.It is all a bit of guess work as we are never going to be able to trot out there with a tape measure. in summary, Use smallest possible aperture f16-f22 and accept the diffraction and also noise from higher ISO Focus on a point in the middle of the scene to make the maximum use of your available DoF If it still does not fit, wait for the birds to align themselves a bit better. It might never happen but if it does, magic.

05-04-2016, 09:24 PM	#11
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by UncleVanya Answer: Get closer. If you get closer, the DoF is reduced.

05-04-2016, 09:42 PM	#12
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,446	Originally posted by clackers If you get closer, the DoF is reduced. ", use shorter focal length." the two are part of single answer. Using a shorter focal length will reduce image size and require that the person be closer but the shorter focal length can improve DOF depending on the amount of change. Not sure if you can still get close enough and not spook the birds but that's my intention. Did I make a mistake?

05-05-2016, 07:27 AM	#15
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Great shot! There are also some specialized sharpening tools (plugins, standalone programs) that are decent. Topaz has some of these things and is partnered with the forum here, or you can try the (now free) Nik Effects from Google, which also has some sharpening tools. Yes, it can make the workflow a little longer and most of these (all?) force you to work with tiff instead of dng (and tiff take much more space), but they can give you good results. It can be worth it for some special photos. You do cropping and rotating first, then NR, then presharpening, all the PP, and then the output sharpening. Especially if you do prints, sharpening is important