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Chris Brennan
06-29-2011, 10:40 PM
I've been privileged to attend several sessions conducted by a master falconer recently, and had some great opportunities to photograph some of his magnificent hawks and falcons in action. A shot which I've tried to make recently is a hawk flying off a perch flying right at me from a distance of about 60'. I'm using a 7D with a 300mm lens and have tried both AI servo as well as one shot focus, as a friend suggested, without too much success in "nailing" the focus. Can anyone make some suggestions for what to try next?

John Chardine
06-30-2011, 09:18 AM
Hi Chris- At the risk of jumping in before one of the BPN Birds in Flight experts, I'll mention a few things. BTW I do a lot of BIF photography and on many occasions the birds are coming directly at me. Here's a few things I have learned here at BPN and from experience:

1. Experiment with the various AF settings of your camera. I know the 7D has options to auto shift the focus point if the subject moves off the target.

2. Don't use One shot focus. In the time between the AF system locking onto the focus target (the front of the bird, bill, eye, forehead etc) and the shutter release, the bird will have moved towards you and out of the (narrow) depth of field (I'd be interested to know what your friend was thinking here!). The faster the bird is flying, the more OOF it will be. Set your 7D to AI Servo.

3. Try to pick up focus on the target early and "bump" the focus at regular intervals as it approaches. This entails letting your finger briefly off the focus button (shutter release, AF-On button, etc) then picking the focus back up as it approaches. I find you can track the bird more reliably this way. If you don't need close focus, set your focus range to the distant setting to avoid "hunting" and slowing down the AF. Also pre-focus manually at the focus pick-up point to speed up acquisition. If the subject is small in the frame at 60', your AF system may have trouble acquiring AF. In this case let it come closer. Also, bright backgrounds can throw off your AF and cause focus problems.

4. Hand-hold to increase your ability to track the subject. Shut down the lens a little from wide open (for optimal performance) and set the ISO so that you have a shutter speed of say 1/1000s or faster. I like to use 1/1600s or faster. At these shutter speeds you can probably turn IS off on the lens to improve IQ, although many say you don't need to do this. If you keep it on set your IS to mode 2 because you will be panning even though the bird is coming towards you.

5. There is an argument out there that you should give the AF system sufficient time to determine focus by using a slower frames per second rate than the max. I shoot a 1DIV and frankly don't see a difference in using 10fps and a slower rate. May be worth an experiment.

6. Make lots of images because they won't all be sharp, sometimes distressingly so!

7. Practice, practice, practice, practice!

David Stephens
06-30-2011, 09:56 AM
I'd add a couple of things to John's reply; bump up the ISO to give shutter speed and ability to stop down (for instance, shoot at ISO 800 in full sun); stop down to f/11 or so to maximize your DOF; set the shutter speed in the 1/1600 to 1/2000th second range for stabilty.

Shoot in burst of a two or three and keep "bumping" your AF. The AI servo mode anticipates the bird's movement, but you have to guard against the camera focusing on the BG. In these conditions the birds are usually flying low and the BG is trees or buildings rather than sky, so I use single-point AF so that the camera won't grab onto the BG unless I miss. Using a "bumping" technique, only updating AF when you're certain that the AF point is on the bird. Shooting at f/11 you don't have to get the eye because the eye will be in focus if you get the head, front of chest or some leading edge.

BTW, this is one of the hardest shots to get. If there's a radio controlled model airplane club, go out to their field and practice on their planes. They'll welcome you and you can offer the copies of the "keepers".

John Chardine
06-30-2011, 11:32 AM
David- The problem with shutting down, especially on the 7D is that you start seeing the effects of diffraction. Also on the 7D, this may necessitate a noisy ISO setting, particularly in good light- e.g., overcast, to get the SS you need. I prefer shutting down the lens a bit and keeping my SS fast with a minimum of ISO boost.

David Stephens
06-30-2011, 12:14 PM
David- The problem with shutting down, especially on the 7D is that you start seeing the effects of diffraction. Also on the 7D, this may necessitate a noisy ISO setting, particularly in good light- e.g., overcast, to get the SS you need. I prefer shutting down the lens a bit and keeping my SS fast with a minimum of ISO boost.

Concern over diffraction is one reason I suggested f/11, rather than a smaller aperture. In actual usage, I find that the 7D offers an excellent IQ, including detail, at ISOs up to 800 and f-stops as small as f/11.

I think that birds flying straight at you have a higher risk of poor IQ due to OOF tracking than to less than perfect performance due to diffraction and that getting more DOF is a better trade-off than minimization of diffration. In other circumstances I'd opt for lower ISO and wider aperture.

We're both right, any setting is a compromise. I just wanted to show an alternative for consideration by the OP.

John Chardine
06-30-2011, 12:42 PM
Understood. No problem. And it's given me some food for thought next time I'm shooting gannets at Boanventure Island with the 1DIV.

Melissa Groo
06-30-2011, 04:53 PM
John, in your helpful points for BIF on the 7D above, you write, At these shutter speeds you can probably turn IS off on the lens to improve IQ. This is the first I've heard that IS can degrade image quality. Have there been any threads on this in the past here? Any way to definitively know the answer to this (aside from doing a comparison test oneself, which I will probably do)? Thanks in advance for any info.

David Stephens
06-30-2011, 05:26 PM
John, in your helpful points for BIF on the 7D above, you write, At these shutter speeds you can probably turn IS off on the lens to improve IQ. This is the first I've heard that IS can degrade image quality. Have there been any threads on this in the past here? Any way to definitively know the answer to this (aside from doing a comparison test oneself, which I will probably do)? Thanks in advance for any info.

We'll see what John says, but I leave IS on in these situations, but I'm usually hand holding. The IS helps me to hold the AF steady as I aim for the head or a leading edge. Aiming for the eye is a nobel cause, but tough to actually achieve with a bird coming at you at any great speed.

On a tripod, IS on or off depends a lot on the IS program in your particular lens.

John Chardine
06-30-2011, 07:49 PM
John, in your helpful points for BIF on the 7D above, you write, At these shutter speeds you can probably turn IS off on the lens to improve IQ. This is the first I've heard that IS can degrade image quality. Have there been any threads on this in the past here? Any way to definitively know the answer to this (aside from doing a comparison test oneself, which I will probably do)? Thanks in advance for any info.

Hi Melissa- The VR/IS piece comes from an article by Thom Hogan here:

http://www.bythom.com/nikon-vr.htm

Have a read and see what you think. One caveat is that Hogan is talking about Nikon's VR system. Canon's IS system may work differently. However, I suspect they are similar in many respects.

Roger Clark
06-30-2011, 08:40 PM
We'll see what John says, but I leave IS on in these situations, but I'm usually hand holding. The IS helps me to hold the AF steady as I aim for the head or a leading edge. Aiming for the eye is a nobel cause, but tough to actually achieve with a bird coming at you at any great speed.

On a tripod, IS on or off depends a lot on the IS program in your particular lens.

I have tested my telephoto lenses (300 f/4 L iS, 300 f/2.8 L IS, and 500 f/4 L IS). I have detected no difference in image quality at high shutter speeds on either the 500 or 300 f/2.8. I have detected degradation at shutter speeds above about 1/2000 second with IS on with the 300 f/4 L IS. The 300 f/4 has an older IS system.

Roger

Roger Clark
06-30-2011, 09:02 PM
3. Try to pick up focus on the target early and "bump" the focus at regular intervals as it approaches. This entails letting your finger briefly off the focus button (shutter release, AF-On button, etc) then picking the focus back up as it approaches. I find you can track the bird more reliably this way. If you don't need close focus, set your focus range to the distant setting to avoid "hunting" and slowing down the AF. Also pre-focus manually at the focus pick-up point to speed up acquisition. If the subject is small in the frame at 60', your AF system may have trouble acquiring AF. In this case let it come closer. Also, bright backgrounds can throw off your AF and cause focus problems.

Hi John,
Perhaps I'm not understanding what your are saying here. If the AF point is on the subject and you remain on the subject, there is no need to bump the focus. Keep your finger half pressing the shutter button (or AF on button) and let the system track the subject. AI servo is designed to tract the subject. If you stop the tracking to then bump the focus, you are making the system fall behind and then it needs to catch up. If you keep on the subject, the system will smoothly track the subject, adjusting for any changing speed. The only time to bump focus is if you slip off the subject, then stop AF and restart when the AF point is back on the subject. Perhaps this is what you meant?



4. Hand-hold to increase your ability to track the subject. Shut down the lens a little from wide open (for optimal performance) and set the ISO so that you have a shutter speed of say 1/1000s or faster. I like to use 1/1600s or faster. At these shutter speeds you can probably turn IS off on the lens to improve IQ, although many say you don't need to do this. If you keep it on set your IS to mode 2 because you will be panning even though the bird is coming towards you.

There is another reason for IS not having to do with IQ. IS steadies the image for the AF system to determine the focus position and focus velocity. Without IS, AF velocity will be more erratic, thus focus is likely to wander more frame to frame.



5. There is an argument out there that you should give the AF system sufficient time to determine focus by using a slower frames per second rate than the max. I shoot a 1DIV and frankly don't see a difference in using 10fps and a slower rate. May be worth an experiment.


I do see occasionally that the first frame in a sequence is slightly out of focus (including with the 1DIV, but other cameras too). This is another argument against bumping focus when one does not need to. If the system is accurately tracking the subject, then as each frame is fired, the focus will remain spot on.

Roger

Chris Brennan
06-30-2011, 11:30 PM
Thanks for all your advice!

Here's an image which was made during one of the sessions:
95909

It's perhaps one of my better efforts but it clearly needs better technique. The falconry field is in bright sunlight throughout the day, and this location has a busy background which tends to throw off the center AF point unless I'm right on the bird. I did bump up my ISO to 800 to get a shutter speed of 1/2000 but kept my aperture at f7.1 because the DLA on the 7D is 6.8. I was hand-holding with IS on.

Since obviously there's no "magic formula", and I don't need a "secret handshake" to join the ranks of successful "bird flying at you" club, I'll continue to practice, practice, practice... practice!

John Chardine
07-01-2011, 05:08 AM
Hi Roger- Very good points. I like the idea that IS steadies the image for the AF system. Re. bumping the focus, I have found in some situations that the AF system just fails to stay on the subject- almost always this is my likely my fault but sometimes it just locks on to something else after tracking the subject for a while (there is probably an AF settings adjustment that would reduce this effect). Once it locks on it seems very difficult to get back to the subject and reacquire focus before the bird flies past you. This is when I use the bumping technique. I have noticed that this occurs in certain lighting conditions and causes the AF system to have trouble to begin with. I mentioned it above because Chris seemed to be having a problem with AF. I agree that in normal circumstances, when the AF system appears to be working, it is not necessary. Two weeks ago at Bonaventure I never had to use it once on incoming gannets.

The slower frame rate idea is another one of Thom Hogan's and it seems to make sense on first principles. At 10 fps the mirror is not down very much and the AF system has much less opportunity to gather data. This problem is made worse if the subject is moving quickly towards you. One great feature with the 1DIV is that you can program the frame rates so if the default slow rate (L setting) is too low, just bring it up. I have tried 6 and 7 fps instead of 10 but as I mentioned above, it seems to make little difference with the 1DIV. Maybe in conditions that cause problems with the AF it would be a way of dealing with the situation.

Here's his essay on autofocus (note the head-on eagle at the top of the piece!)

http://www.bythom.com/autofocus2.htm

Chris Brennan
07-01-2011, 06:41 AM
I should have also mentioned that I have my 7D set for the slowest AF tracking. Because the background is so "busy", I felt that for as long as I was able to track the bird in the viewfinder, with the center focus point (or the center 9 focus points) staying on the bird, it would stay in focus. The Harris Hawks which the falconer typically flies from this perch are faster than an eagle but much slower than a peregrine so it appears I just need to practice more, at high shutter speeds, and perhaps higher apertures (forgetting about diffraction limits for now) and using the highest fps setting (8 fps).

Roger Clark
07-01-2011, 07:24 AM
Hi Roger- Very good points. I like the idea that IS steadies the image for the AF system. Re. bumping the focus, I have found in some situations that the AF system just fails to stay on the subject- almost always this is my likely my fault but sometimes it just locks on to something else after tracking the subject for a while (there is probably an AF settings adjustment that would reduce this effect). Once it locks on it seems very difficult to get back to the subject and reacquire focus before the bird flies past you. This is when I use the bumping technique. I have noticed that this occurs in certain lighting conditions and causes the AF system to have trouble to begin with. I mentioned it above because Chris seemed to be having a problem with AF. I agree that in normal circumstances, when the AF system appears to be working, it is not necessary. Two weeks ago at Bonaventure I never had to use it once on incoming gannets.

The slower frame rate idea is another one of Thom Hogan's and it seems to make sense on first principles. At 10 fps the mirror is not down very much and the AF system has much less opportunity to gather data. This problem is made worse if the subject is moving quickly towards you. One great feature with the 1DIV is that you can program the frame rates so if the default slow rate (L setting) is too low, just bring it up. I have tried 6 and 7 fps instead of 10 but as I mentioned above, it seems to make little difference with the 1DIV. Maybe in conditions that cause problems with the AF it would be a way of dealing with the situation.

Here's his essay on autofocus (note the head-on eagle at the top of the piece!)

http://www.bythom.com/autofocus2.htm

Hi John,
OK, we agree.

Regarding Hogan's web page, the first bullet is completely wrong. AF system work in a variety of light, and f/8 versus f/5.6 is a minor difference compared to full sun to twilight (many stops). A 500 mm f/4 lens will even AF well on brighter stars. If you have enough light to stop the action (except for maybe wing tips), there is enough light for the AF system.

I'll explain more in my post to Chris from the image he posted this morning. It may explain why you observed some of the effects of the AF moving when with a BIF and you are still perfectly on the bird.

Roger

Roger Clark
07-01-2011, 07:55 AM
Thanks for all your advice!

It's perhaps one of my better efforts but it clearly needs better technique. The falconry field is in bright sunlight throughout the day, and this location has a busy background which tends to throw off the center AF point unless I'm right on the bird. I did bump up my ISO to 800 to get a shutter speed of 1/2000 but kept my aperture at f7.1 because the DLA on the 7D is 6.8. I was hand-holding with IS on.

Since obviously there's no "magic formula", and I don't need a "secret handshake" to join the ranks of successful "bird flying at you" club, I'll continue to practice, practice, practice... practice!

Chris,

The image you posted tells a lot. First it is not a great time of day: harsh light. But the bigger problem is the relatively dark bird and bright background.

AF systems works on an out-of-focus image using a mask to collect light from each side of the lens (think of a mask you put over the lens with two holes near each side--the AF system does this with a little mask behind the mirror in the camera body--it's actually on the bottom of the camera). Think of two graphs of intensity that are mirror images of each other representing a the intensity along a line in the scene from the two sides of the lens. The two graphs are from light from each side of the lens (or up and down with some AF sensors). The system has to decide what in this graph should be in focus. What the Canon system does is go for a bright, highest contrast point. In a situation like your image, the background is very busy with many bright spots and deep shadows. The bird is relatively darker, so the AF system chooses the background. The next problem is that because the AF system is working on an out-of-focus image (even when the subject is in focus) the AF system is seeing a larger area than the AF rectangle in the viewfinder. Thus for the size of the bird in your image, the AF system is also seeing the background even if you had the AF point perfectly on the subject. Thus even with perfect technique, the system will see the higher contrast background and lock onto the background.

Your best hope is to use one/all of the following options.

1) Best choose a different time of day with better light and that would also cast a shadow on the background. Some overcast would would help diffuse the shadows and reduce contrast in the background and the subject.

2) Longer lens to fill more of the frame.

3) focus limit: if you can position yourself so that you can limit focus to exclude
the background so the AF system only looks at closer subjects (the bird).

4) Pre focus for the bird being closer so that it fills more of the frame, then when the bird reashes that point, half press the shutter to engage AF tracking.

5) Use bump focus method to try and get the subject back in focus if the AF locks onto the background.

For John, when you've had the AF move off the BIF when you were tracking the subject well, the AF system probably saw a brighter high contrast subject in the background. In those situations, if you see the bright spot coming, probably best to let off of the AF and wait for the bird to pass it. This is very hard as things can happen so fast and we have such a small field of view when looking through the viewfinder.

One final analogy. Think of a plot of the stock market over time. The AF system is making a similar looking plot of intensity in the scene, and among all those ups and downs trying to decide what should be in focus. And then the graph is changing and so the AF system not only must decide on what to focus on, but which feature to track. It's amazing it works as well as it does!

You can google "phase detect autofocus" and get more info.

Good luck,
Roger

Chris Brennan
07-01-2011, 11:33 AM
Roger -

WOW! Thank you for the very informative response! I clearly have a lot to do but most if not all your points makes a lot of sense, and I will work with all of the ones (that are in my power) to get better images!

Sadly, the falconer only runs his sessions from mid-morning to early afternoon. I've been to several of his sessions now, and have decided that I'll wait for the next day when the weather is forecast to be overcast as I think the lighting will help greatly with capturing the images the way I want them.

Also, since the sessions are fairly well controlled, I'll get someone to stand in the area where I expect the best shots to come from, and pre-focus on that spot... that may help as well.

And I think I will also try shooting from ground level to get a different perspective both on the bird as well as reduce the busy background clutter!

Thanks again!

Jim Neiger
07-10-2011, 05:15 PM
Shots coming at you are the most difficult type of flight shots because the speed of the bird relative to you is much greater. This means that you will need a faster shutter speed for birds flying at you. The reason for this is because there is no way to pan with the bird and match speed. High shutter speed usually also means large aperture and small DOF. This means you must focus on the bird's head to get a shot that is sharp in the right places or you must make the bird small in the frame to get more DOF relative to the bird. The head is a small target and this also increases the difficulty. Many people on this forum have been giving advice about using my bump focus technique, but few of them truly understand it and how to use it. In this example, it is likley that only one of the three reasons for using the bump focus technique will be usefull. I bet that none of the people talking about bump focus can correctly name the reason for using it and why in this example. Hint: It is the least most important use of the bump technique.

John Chardine
07-10-2011, 05:28 PM
Of course when I mentioned the bump technique Jim, I thought of you but but you were not around when the thread came out and it would have been remiss of me not to mention it. All I know is it works for me sometimes and quite honestly I don't care about why so long as it works. To be honest, I have only found it useful in maybe two occasions, ever, so for me I hardly need it. I only mentioned it in this case because the OP was having trouble getting focus.

Jim Neiger
07-10-2011, 05:36 PM
Of course when I mentioned the bump technique Jim, I thought of you but but you were not around when the thread came out and it would have been remiss of me not to mention it. All I know is it works for me sometimes and quite honestly I don't care about why so long as it works. To be honest, I have only found it useful in maybe two occasions, ever, so for me I hardly need it. I only mentioned it in this case because the OP was having trouble getting focus.

John,

I wasn't specifically talking about you or any other one individual. You were not the only one to mention it in this thread. Seems that all of the people that suggest the bump technique fail to consider that there are three very different applications or reasons for using it and they do not give the correct reason and why the bump technique is usefull. I think this is because they do not know the reasons or how best to apply the technique. Bumping the focus is a technique. Applying it correctly in the two most important applications is a skill that must be learned and practiced. ALOT of practice is required to develop these skills. It will be interesting to see if anyone can identify the one reason and how to apply it while giving the reasons why the other two reasons for using the bump technique would be unlikely to be usefull in this example. If no-one gets it, I will provide the answers later. There is a thread I posted about bump focus technique that supplies all you need to know to get the answer. You just need to find the thread and try to figure out how it relates to this example.

David Stephens
07-10-2011, 05:37 PM
...High shutter speed usually also means large aperture and small DOF. This means you must focus on the bird's head to get a shot that is sharp in the right places or you must make the bird small in the frame to get more DOF relative to the bird. The head is a small target and this also increases the difficulty. ...

Jim, why wouldn't you use higher ISO, within limits, to inable a smaller aperture and faster SS at the same time?

Jim Neiger
07-10-2011, 05:47 PM
Jim, why wouldn't you use higher ISO, within limits, to inable a smaller aperture and faster SS at the same time?

If you focus on the body of a bird flying at you and the bird is large in the frame, then the head will be so far in front of the body that it is very unlikely that you will be able to get enough DOF to make the head very sharp and still get an image that is of acceptable quality. Keep in mind that SS is critical since you can't pan with the bird and the amount of DOF needed is large in relation to the FOV. Even at high ISO and F11 - F16 the DOF is not likely to be enough. The answer is to focus on the head or make the bird smaller in the frame and then crop alot.

David Stephens
07-10-2011, 06:15 PM
If you focus on the body of a bird flying at you and the bird is large in the frame, then the head will be so far in front of the body that it is very unlikely that you will be able to get enough DOF to make the head very sharp and still get an image that is of acceptable quality. Keep in mind that SS is critical since you can't pan with the bird and the amount of DOF needed is large in relation to the FOV. Even at high ISO and F11 - F16 the DOF is not likely to be enough. The answer is to focus on the head or make the bird smaller in the frame and then crop alot.

So, as we all know, results are dependent on the size, distance and speed of the bird.

I still don't understand why you'd keep the aperture wider than needed to limit defraction to a reasonable level. Seems to me that'll it'll always increase your margin for error.

Jim Neiger
07-10-2011, 06:41 PM
So, as we all know, results are dependent on the size, distance and speed of the bird.

I still don't understand why you'd keep the aperture wider than needed to limit defraction to a reasonable level. Seems to me that'll it'll always increase your margin for error.

I'm not saying that you should be wide open for this shot, but it is possible that you will need to be wide open to get the SS you need. This depends on many things such as; available light, capability of the camera in regards to noise at the ISO settings used, size of bird in the frame, plane of critical focus, and the speed of the bird.

I don't think you would be likely to get an image with the head and eyes sharp where the bird is large in the frame unless you focus on the head, assuming that the bird is a fast flying hawk or falcon.

David Stephens
07-16-2011, 12:39 PM
John,

I wasn't specifically talking about you or any other one individual. You were not the only one to mention it in this thread. Seems that all of the people that suggest the bump technique fail to consider that there are three very different applications or reasons for using it and they do not give the correct reason and why the bump technique is usefull. I think this is because they do not know the reasons or how best to apply the technique. Bumping the focus is a technique. Applying it correctly in the two most important applications is a skill that must be learned and practiced. ALOT of practice is required to develop these skills. It will be interesting to see if anyone can identify the one reason and how to apply it while giving the reasons why the other two reasons for using the bump technique would be unlikely to be usefull in this example. If no-one gets it, I will provide the answers later. ..

Well? :2

Are you waiting on us to buy your book? :c3:

Chris Brennan
07-16-2011, 01:22 PM
If you focus on the body of a bird flying at you and the bird is large in the frame, then the head will be so far in front of the body that it is very unlikely that you will be able to get enough DOF to make the head very sharp and still get an image that is of acceptable quality. Keep in mind that SS is critical since you can't pan with the bird and the amount of DOF needed is large in relation to the FOV. Even at high ISO and F11 - F16 the DOF is not likely to be enough. The answer is to focus on the head or make the bird smaller in the frame and then crop alot.

Jim -

I had an opportunity to visit with the falconer again, and this time tried some different techniques including your "bump" focus technique (I've got a LONG way to go with that!) along with a faster SS and smaller aperture. But you were certainly correct in saying that even smaller wouldn't be enough as even at 1/1250 and f11, I've not "frozen" the bird in flight. But I don't mind doing the practice.. especially if I have a golden eagle for a subject!

David Stephens
07-16-2011, 01:51 PM
Well Chris, better, but not quite there.

It looks like the camera focused on the top of the head. You might try an even higher shutter speed with a resulting larger aperture.

Notice that the eye is in the dark. You want to position yourself so that the eye will be in the light. Even in the wild, always be thinking about where the light is coming from and approach with the light behind you, when possible. For this event, you should have been a good ways to your left, if possible. Strong daylight, like here, dictates high awareness of light direction.

You're so close here that you have to focus on the eye area with single-point.

Looks like great practice.

Chris Brennan
07-16-2011, 05:00 PM
Dave -

Thanks for your comments!

If I understand you correctly, I should be in the 1/1600 - 1/2500 range, yes? In order to achieve that and stay at ISO 800, I'll need to open up to f8 or so. Staying at f11 would be ideal but I'm a little reluctant to push the 7D beyond the ISO 800 threshold but will certainly try it out next time...

Unfortunately, I was limited in where I could stand with this particular bird. As you can see, she is on a tether and being left would have been in her "zone"... and one does NOT want to be in the flight path of a very large (2' high, 9 lbs.) golden eagle or between her, and a tasty mouse!

John Chardine
07-16-2011, 05:16 PM
Hi Chris- "Staying at f11" is definitely not ideal for this type of photography. Just take a look at the many birds in flight images posted here and see how many used f11. For birds in flight the clear priority is shutter speed. Why do you think you need f11? Surely not for DoF. The keepers will have the eye in focus regardless of what f-stop you use and you are often working at distances which give you a healthy DoF at f7.1-f8.

David Stephens
07-16-2011, 05:41 PM
Dave -

Thanks for your comments!

If I understand you correctly, I should be in the 1/1600 - 1/2500 range, yes? In order to achieve that and stay at ISO 800, I'll need to open up to f8 or so. Staying at f11 would be ideal but I'm a little reluctant to push the 7D beyond the ISO 800 threshold but will certainly try it out next time...

Unfortunately, I was limited in where I could stand with this particular bird. As you can see, she is on a tether and being left would have been in her "zone"... and one does NOT want to be in the flight path of a very large (2' high, 9 lbs.) golden eagle or between her, and a tasty mouse!

SS takes priority over aperture, so yes, open up to achieve a higher SS. I generally try to keep my 7D at ISO 800 or less and you've got plenty of light to do this here. However, in lower light, going to ISO 1600 yields good results, so long as you don't under expose.

Understood about the inability to move. the harsh light and shadow on the eye will make it very hard to get a "keeper" but it's good practice. Since the bird is brown, you can use +EV to "expose right" (to the right of the histogram) so that you can pull up more shadow detail at the eye.

All that said, getting the eye in focus is the most critical element of this shot. Keep trying. Big, relatively slow birds like this are good for practice.

Jim Neiger
07-17-2011, 11:51 AM
Well? :2

Are you waiting on us to buy your book? :c3:

Oops - I forgot.

The answer is that the only use for bump focus in this example would be the least important use, bumping the focus to pre-focus. You would do this by pointing the camera at something at the same distance as where you first hope to focus on and shoot the subject. In this case I would focus on the ground about 10 feet in front of the perch that the bird takes off from. This means that I intend to focus on the bird and make my first image when the bird is about 50 feet away. (Op stated the perch was about 60 feet away) When the bird takes off, I would try to focus on the birds head about the time he reaches the pre-focused distance. I would them try to keep focus and shoot as the bird flies towards me. If I miss, I am likely done for that flight run. If I don't miss, I get several shots until the bird gets too close (clipped wings and inside min focus distance).

The other uses for bumping the focus; Overriding tracking sensitivity delay; and
Keeping focus close while avoiding focusing on bg until ready to shoot, do not apply. The short, head on flight is too quick for either of those reasons for bumping to be useful. Please read this thread for more info on bumping the focus for bif:
http://www.birdphotographers.net/forums/showthread.php/1949-Bumping-the-focus-for-BIF?highlight=bumping+focus+bif

Jim Neiger
07-17-2011, 11:56 AM
Chris,

Try shooting early in the morning when the light isn't as harsh. I would also suggest shooting from a high point if possible. If it was me, I would stand on top of the bed cover for my pickup truck. The higher angle looking down will help. I would also suggest using at least 1/2000 for shutter speed.

I once was hired to shoot a client's Harris Hawk, so I understand almost exactly what your shooting conditions are like. I don't normaly shoot or post captives, but in this case I got paid $1000 for a three hour shoot. If it will help I will post an example, but I have never posted a captive bird shot, so I'm somewhat hesitant to do that now.

For this shoot I would suggest AF-c with only the center point active. I would not use expansion when the BG is close and busy like in your sample images. For smoother and/or more distant bgs, AF expansion points may help.

Roger Clark
07-17-2011, 03:13 PM
Oops - I forgot.

The answer is that the only use for bump focus in this example would be the least important use, bumping the focus to pre-focus. You would do this by pointing the camera at something at the same distance as where you first hope to focus on and shoot the subject. In this case I would focus on the ground about 10 feet in front of the perch that the bird takes off from. This means that I intend to focus on the bird and make my first image when the bird is about 50 feet away. (Op stated the perch was about 60 feet away) When the bird takes off, I would try to focus on the birds head about the time he reaches the pre-focused distance. I would them try to keep focus and shoot as the bird flies towards me. If I miss, I am likely done for that flight run. If I don't miss, I get several shots until the bird gets too close (clipped wings and inside min focus distance).

The other uses for bumping the focus; Overriding tracking sensitivity delay; and
Keeping focus close while avoiding focusing on bg until ready to shoot, do not apply. The short, head on flight is too quick for either of those reasons for bumping to be useful. Please read this thread for more info on bumping the focus for bif:
http://www.birdphotographers.net/forums/showthread.php/1949-Bumping-the-focus-for-BIF?highlight=bumping+focus+bif

Jim,

You are describing my point #4 in pane 15. Anyway, regarding bump focus, I used bump focus long before bpn (I never had a name for it), but I do prefer following the subject with the AF point on the eye. The phase detect AF systems are designed to track a subject, and do it very well in many cases. Smooth tracking is also a learned method. Examples of such tracking are videographers tracking a BIF (e.g. Planet Earth series and other National Geographic shows). So it can be done, and in my opinion, it's really up to the individual to find what works best for them.

When I'm tracking with a big lens on a tripod with a gimbal head, I keep both hands on the camera and track with both hands, but leaving my right index finger the ability to press the shutter button, including letting off to bump focus if needed. I also hand hold with methods described in other recent threads here. Both methods have merit (tripod and hand held) but as focal length increases (around 700 mm and higher on 1.3x crop sensors) I find personally that I get smoother tracking on a tripod and most frames in focus (all in focus unless I slip off the subject) at the longer focal lengths. Of course those little faster birds that fly erratically are tough with any method.

But in my opinion, purposely bumping focus while successfully tracking a subject is making the camera constantly catch up, which means during the catch-up period your subject is not in focus. Whereas if one is nicely tracking the subject, keeping the AF predictve AF working means the velocity is more accurately being tracked.

So for the OP, I would use a single point AF on the bird from its rest position
and try and track it constantly. You will have better chance of tracking if you can get on the sunlit side of the subject. Tracking a shadow rarely works. Also in contrast to getting higher, I would suggest getting lower. If you can get low enough, you might have blue sky behind the bird and then tracking will be easier for you and the AF system in that there is no background to lock on to. Even if you don't get blue sky, getting lower could help put more distance between the bird and the background.

Roger

Jim Neiger
07-17-2011, 06:22 PM
Jim,

You are describing my point #4 in pane 15. Anyway, regarding bump focus, I used bump focus long before bpn (I never had a name for it), but I do prefer following the subject with the AF point on the eye. The phase detect AF systems are designed to track a subject, and do it very well in many cases. Smooth tracking is also a learned method. Examples of such tracking are videographers tracking a BIF (e.g. Planet Earth series and other National Geographic shows). So it can be done, and in my opinion, it's really up to the individual to find what works best for them.

Roger,

I think what you are doing when you bump the focus and what I'm doing are two different things. It is apparent from your comments that my attempts at explaining my methods have failed.


When I'm tracking with a big lens on a tripod with a gimbal head, I keep both hands on the camera and track with both hands, but leaving my right index finger the ability to press the shutter button, including letting off to bump focus if needed. I also hand hold with methods described in other recent threads here. Both methods have merit (tripod and hand held) but as focal length increases (around 700 mm and higher on 1.3x crop sensors) I find personally that I get smoother tracking on a tripod and most frames in focus (all in focus unless I slip off the subject) at the longer focal lengths. Of course those little faster birds that fly erratically are tough with any method.

WHen you compare a skilled photg shooting bif hand held to a skilled tripod shooter, the hand held photographer will produce many more quality images. In fact it is likley to be ten times as many or more.


But in my opinion, purposely bumping focus while successfully tracking a subject is making the camera constantly catch up, which means during the catch-up period your subject is not in focus. Whereas if one is nicely tracking the subject, keeping the AF predictve AF working means the velocity is more accurately being tracked.

Again, I have failed to explain bumping so that you understand it.


So for the OP, I would use a single point AF on the bird from its rest position
and try and track it constantly. You will have better chance of tracking if you can get on the sunlit side of the subject. Tracking a shadow rarely works. Also in contrast to getting higher, I would suggest getting lower. If you can get low enough, you might have blue sky behind the bird and then tracking will be easier for you and the AF system in that there is no background to lock on to. Even if you don't get blue sky, getting lower could help put more distance between the bird and the background.

Roger

Chris,

If you can get the handler to throw meat high in the air you will get some blue sky bg shots and dramatic positions, but you can do this from high or low. Getting high will open up the possiblity for more eye level and top side views. Shooting nearly wide open will help minimize the impact of the close bg. You can do more with the bg during post processing. A heavy dose of NR for example.

Chris Brennan
07-18-2011, 10:46 AM
Jim -

Many thanks fo all your words of wisdom!

All my opportunities with the falconer have been while he is conducting falconry demonstrations for paying participants. He and I have come to an agreement that he can use any of my images for his marketing purposes in exchange for me being allowed to photograph his birds. I no longer work as professional photographer so this is a win-win for both of us although I suspect that some of you may be cringing at the agreement...

Unfortunately, these sessions are held between the hours of 10:30 am and 1 pm so I'm essentially "between a rock and a rock" when it come to timing and where the sun is. That said, I hope to have these occasional opportunities for many months to come and hope to be able to shoot well into the fall when the sun angle is different and there are chances for more cloudy days to soften the light.

Getting elevated though is an excellent idea and I'll plan to try that next time out.

David Stephens
07-18-2011, 11:11 AM
Chris, if you're going to let him use the images for promotional purposes then suggest that you need to take some at the optimal time in the optimal position. Depending on the best light, do it nearer dawn or dusk. It would be little or no trouble for him to set up a shoot just for you.

If you did it in the morning, you could get your bird shots and then stay around to get shots of the crowd. With the falconer's permission, shoot from behind him and show the birds and the "crowd" watching, etc., etc. You get excited and he'll get excited.

Jim Neiger
07-18-2011, 12:06 PM
Captive bird!

96731
1D3, 500mm, 1/2000, F5.6, ISO 800, manual exposure, CAPTIVE BIRD

Chris,

Here is a sample from a captive Hawk shoot I was paid to do. I don't normaly shoot or post captive birds, and this is the only exception I have made so far. The bird's name is Bandit.

Chris Brennan
07-18-2011, 06:15 PM
Simply stunning!! A gorgeous shot with great angle, and shows the Harris hawk's plumage beautifully!

I'll be working on getting something that good... someday!