Eagle BIFs and URGENT AF-S question to birders/tele shooters/trouble shooters!

Started Jan 30, 2013 | Discussions
windsprite
windsprite Senior Member • Posts: 2,563
Eagle BIFs and URGENT AF-S question to birders/tele shooters/trouble shooters!

In less than a week, I'm leaving on a trip to eastern Hokkaido, Japan, to shoot some white-tailed eagles and other birds, but I'm having a strange problem with my 300/4 AF-S. I bought it second hand a couple of years ago, and it was perfect, but I recently had the AF-S motor replaced, and now the focus seems to be all messed up. I'm hoping somebody has some insight, and fast!

First, I will show some shots I took at this Hokkaido location last year, where my gear functioned perfectly. See the following post.

Julie

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windsprite
OP windsprite Senior Member • Posts: 2,563
BIFs and WIFs

Here are four of the action shots I took last year. D700, 300/4, and 1.4x telecon, wide open. This was my first serious attempt at shooting BIFs, and the equipment really came through for me. I only shot the eagles for an hour or so, and the light could have been better, but focus-wise, most of my shots were keepers.



white-tailed eagle

white-tailed eagle, juvenile

black-eared kite

white-tailed eagle and red-crowned crane

If for whatever reason these links don't work, the gallery of four images is here:

http://www.dpreview.com/galleries/3636978925/albums/cranes-and-eagles-2012

Normally I shoot "WIFs": whippets in flight. My husband and I sometimes do competitive distance frisbee with our two dogs. I found the settings I use for this sport worked well on the eagles:



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windsprite
OP windsprite Senior Member • Posts: 2,563
The problem

Sorry to make this a very long story, but I have little time, so I'm in panicked problem-solving mode and want to include as many details as possible:

I bought the 300/4 second hand a few years ago, and for over a year, I used it happily on fast-moving subjects (as I wrote in my post above, I own two whippets -- race dogs -- with whom my husband and I sometimes do competitive distance frisbee).  Last fall, the AF-S motor died.  A few weeks ago I was invited on this year's eagle-shooting trip, so I rushed the lens to the Nikon service center in nearby Sapporo, and they replaced the motor.  I was too busy to test it outdoors right away, but shots around the house (between 2 and 10 meters) and out my window showed the focus was just about perfect, like before.  Awesome.

Then yesterday I took it out on our deck and tried shooting some objects around my house (I have a cough and fever right now and can't venture out into the wilderness to test this thing).  I live right in the city, so my subjects were urban junk like TV antennae, electrical poles and insulators, crows, airplanes, etc.

Well, I've noticed that the motor is incredibly jittery when shooting at distant subjects, say more than 20 meters, and no matter what I do, I can't seem to get a sharp picture.  I can see through the OVF that the focus is dancing all over the place, but it's mostly the WRONG place.  It makes a stuttery dit-dit-dit clacking noise, and it's busy to the point where I'm afraid it's going to wear out the motor again in no time.  Again, this dancing and clacking does NOT happen indoors, at distances of around 2-10 meters, even in light so ridiculously low that I can barely see through the OVF and definitely can't hold the lens steady enough for the required shutter speed.  The focus is also spot on in these conditions, even with a telecon attached.

I've tried every setting I can imagine, to no avail.  I thought maybe it was my technique or the weird subjects I've been shooting, but get this:  I go indoors and shoot the same outdoor subject through our dirty triple-pane glass windows, and the focus stabilizes, and everything is fine.  Accurate AF, and no clack-clack dit-dit.

I'm using NO filters on the lens.  My batteries (EN-EL3s) are new and fully charged.  The green focus lamp lights up even though the subject is obviously out of focus.

My preferred setting is AF-C, using the AF-ON button.  AF-S reduces the jitter, but the accuracy doesn't seem much better, and anyway, it's a no-go for eagle BIFs.  Single point (my default) or 9-point AF makes no difference.  I normally have the a4 focus tracking with lock-on set to "short," but changing it to "long" doesn't help.  AF-C is on release priority, and I'd prefer not to change that for fast-paced action photos.

I have the problem with and without the teleconverter.  It happens on the D700 and also a second-hand D300 that I bought the other day.  The position of the focus limiter switch makes no difference.  I've only tried center point so far, because that's what I usually use for action.

It is a little chilly outdoors, but only around freezing (it's probably going to be at least -20 below where I'm going next week).  I will stand inside my house and fire off five or six photos of an object through my glass door at 5-6 fps, and almost all will be in focus.  Then I will stay in the same position, swing the door out of my way, and shoot at the same object, and I'll be lucky if one of the frames is even "sort of" in focus.  The difference is obvious even on the back LCD, without zooming in.  Even my husband, who is not particularly into photography, will actually laugh at how bad the images are!  Then I'll close the door, shoot through the glass, and everything will be OK again.  I could be wrong, but I don't think it can be a temperature-related problem, because I'm standing indoors, and it doesn't seem like there would be enough time for the system to expand/contract.

Since the focus is OK through the windows, I have a hard time believing it's a problem with my technique or settings.  I'm also guessing that fine-tuning the AF would do no good?

That's about all the info I can think of.  This might turn out not to be a problem with the real-life photos I intend to take, but it's making me very nervous.  I would be very happy to learn that I am making some stupid mistake and everything will be fine if I correct it, but for the life of me I can't figure out what it might be.

Has anybody heard of anything like this?!

Am I going to have to take a dirty window from my house on my trip or put a cheap and nasty filter on my lens?!

One last thing that occurs to me is, when I took the lens to the service center a few weeks ago, they cleaned my D700 sensor and updated the firmware (I was on the original FW).  Is anybody aware of any FW  changes that might cause problems?

I called Nikon today, and they have no ideas at all what the problem could be, but they said that if I sent in the lens and one of the bodies, they would check it out and kindly lend me their 300/4 display model if they saw a problem with the lens.  However, even if I send everything in tomorrow (Thursday), I won't have the body and lens back until Monday, and I leave on Tuesday.  And what if they *don't* see a problem?!

I have around 14 hours to figure this out before I have to send or take the lens to Nikon.  I will try and post my test samples a little later, but for now I hope the action shots in the post above will at least reassure you that I'm fairly experienced with telephoto lenses.

Thanks in advance for any help offered!

Julie

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mikew Contributing Member • Posts: 632
Equipment problems before a trip suck...

Because the trip is approaching so soon, I am going to suggest renting a similar lens for this outing.
The 300 f4 shouldn't be prohibitive in cost to rent for a few days. I have many lenses from 16 to 600mm. But I find I still need to fill in a void at times due to something being out of whack. I have had very good luck getting fine equipment that has usually been tested ( i.e., rented ) on lots of different cameras. So your chances of getting a good one, in my experience, are good.

I have no idea what might be wrong with the camera.

Best of luck to you.

Mike

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windsprite
OP windsprite Senior Member • Posts: 2,563
Re: Equipment problems before a trip suck...

mikew wrote:

Because the trip is approaching so soon, I am going to suggest renting a similar lens for this outing.
The 300 f4 shouldn't be prohibitive in cost to rent for a few days. I have many lenses from 16 to 600mm. But I find I still need to fill in a void at times due to something being out of whack. I have had very good luck getting fine equipment that has usually been tested ( i.e., rented ) on lots of different cameras. So your chances of getting a good one, in my experience, are good.

I have no idea what might be wrong with the camera.

Best of luck to you.

Mike

That's something I hadn't thought of, to be honest.  I'm a little reluctant to try it, because at this point I wouldn't have time to test the rental lens, and Nikon is going to lend me one for free anyway.  Plus I'm not sure it's a lens problem to begin with.  But it's a good suggestion, and I'll look into it as another option.  Thanks for the advice, Mike!

Julie

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bikinchris
bikinchris Forum Pro • Posts: 21,531
The only thing I can think of

The only thing I can think of is the contacts between the body and lens. Maybe they are a little dirty.

OR maybe a little play has begun between the body and lens mount? Does it jitter if you hold the camera vertically?

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and formal politeness provide lubrication where people rub together.
Often the very young, the untraveled, the naive, the unsophisticated deplore these
formalities as "empty," "meaningless," or "dishonest," and scorn to use them.
No matter how pure their motives, they thereby throw sand into machinery that does not
work too well at best."
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FrankG Senior Member • Posts: 1,840
Re: The problem

windsprite wrote:

Sorry to make this a very long story, but I have little time, so I'm in panicked problem-solving mode and want to include as many details as possible:

I bought the 300/4 second hand a few years ago, and for over a year, I used it happily on fast-moving subjects (as I wrote in my post above, I own two whippets -- race dogs -- with whom my husband and I sometimes do competitive distance frisbee). Last fall, the AF-S motor died. A few weeks ago I was invited on this year's eagle-shooting trip, so I rushed the lens to the Nikon service center in nearby Sapporo, and they replaced the motor. I was too busy to test it outdoors right away, but shots around the house (between 2 and 10 meters) and out my window showed the focus was just about perfect, like before. Awesome.

Then yesterday I took it out on our deck and tried shooting some objects around my house (I have a cough and fever right now and can't venture out into the wilderness to test this thing). I live right in the city, so my subjects were urban junk like TV antennae, electrical poles and insulators, crows, airplanes, etc.

Well, I've noticed that the motor is incredibly jittery when shooting at distant subjects, say more than 20 meters, and no matter what I do, I can't seem to get a sharp picture. I can see through the OVF that the focus is dancing all over the place, but it's mostly the WRONG place. It makes a stuttery dit-dit-dit clacking noise, and it's busy to the point where I'm afraid it's going to wear out the motor again in no time. Again, this dancing and clacking does NOT happen indoors, at distances of around 2-10 meters, even in light so ridiculously low that I can barely see through the OVF and definitely can't hold the lens steady enough for the required shutter speed. The focus is also spot on in these conditions, even with a telecon attached.

I've tried every setting I can imagine, to no avail. I thought maybe it was my technique or the weird subjects I've been shooting, but get this: I go indoors and shoot the same outdoor subject through our dirty triple-pane glass windows, and the focus stabilizes, and everything is fine. Accurate AF, and no clack-clack dit-dit.

I'm using NO filters on the lens. My batteries (EN-EL3s) are new and fully charged. The green focus lamp lights up even though the subject is obviously out of focus.

My preferred setting is AF-C, using the AF-ON button. AF-S reduces the jitter, but the accuracy doesn't seem much better, and anyway, it's a no-go for eagle BIFs. Single point (my default) or 9-point AF makes no difference. I normally have the a4 focus tracking with lock-on set to "short," but changing it to "long" doesn't help. AF-C is on release priority, and I'd prefer not to change that for fast-paced action photos.

I have the problem with and without the teleconverter. It happens on the D700 and also a second-hand D300 that I bought the other day. The position of the focus limiter switch makes no difference. I've only tried center point so far, because that's what I usually use for action.

It is a little chilly outdoors, but only around freezing (it's probably going to be at least -20 below where I'm going next week). I will stand inside my house and fire off five or six photos of an object through my glass door at 5-6 fps, and almost all will be in focus. Then I will stay in the same position, swing the door out of my way, and shoot at the same object, and I'll be lucky if one of the frames is even "sort of" in focus. The difference is obvious even on the back LCD, without zooming in. Even my husband, who is not particularly into photography, will actually laugh at how bad the images are! Then I'll close the door, shoot through the glass, and everything will be OK again. I could be wrong, but I don't think it can be a temperature-related problem, because I'm standing indoors, and it doesn't seem like there would be enough time for the system to expand/contract.

Since the focus is OK through the windows, I have a hard time believing it's a problem with my technique or settings. I'm also guessing that fine-tuning the AF would do no good?

That's about all the info I can think of. This might turn out not to be a problem with the real-life photos I intend to take, but it's making me very nervous. I would be very happy to learn that I am making some stupid mistake and everything will be fine if I correct it, but for the life of me I can't figure out what it might be.

Has anybody heard of anything like this?!

Am I going to have to take a dirty window from my house on my trip or put a cheap and nasty filter on my lens?!

One last thing that occurs to me is, when I took the lens to the service center a few weeks ago, they cleaned my D700 sensor and updated the firmware (I was on the original FW). Is anybody aware of any FW changes that might cause problems?

I called Nikon today, and they have no ideas at all what the problem could be, but they said that if I sent in the lens and one of the bodies, they would check it out and kindly lend me their 300/4 display model if they saw a problem with the lens. However, even if I send everything in tomorrow (Thursday), I won't have the body and lens back until Monday, and I leave on Tuesday. And what if they *don't* see a problem?!

I have around 14 hours to figure this out before I have to send or take the lens to Nikon. I will try and post my test samples a little later, but for now I hope the action shots in the post above will at least reassure you that I'm fairly experienced with telephoto lenses.

Thanks in advance for any help offered!

Julie

My D7000 intermittently does something very similar to what you are describing with my 300mm F4 AFS although I have never tested to see if double-glazing has any effect on this!  I think it is something to do with intermittent poor contacts between the lens and the body.  Do you notice any looseness or play between the lens and the body?

My D800 does not have any such problem with this lens, just the D7000.

I tried cleaning the contacts on both the D7000 body and the lens contacts but it didn't seem to make any difference but you could try this in case it works in your case.  If that doesn't fix the problem then I would think you are probably going to have to have it sorted out by Nikon service unfortunately.  If so then the idea of an emergency lens hire seems a good one.

Frank

windsprite
OP windsprite Senior Member • Posts: 2,563
Re: The only thing I can think of

bikinchris wrote:

The only thing I can think of is the contacts between the body and lens. Maybe they are a little dirty.

OR maybe a little play has begun between the body and lens mount? Does it jitter if you hold the camera vertically?

Hi Chris,

I think the contacts are OK.  I cleaned the ones on both lens and body before taking them to Nikon, and I assume the service center cleaned them as well.

Maybe everything is *too* clean! 

The mount seems very snug, as usual.

Good thoughts, though.  Thanks for your input,

Julie

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windsprite
OP windsprite Senior Member • Posts: 2,563
Re: The problem

FrankG wrote:

My D7000 intermittently does something very similar to what you are describing with my 300mm F4 AFS although I have never tested to see if double-glazing has any effect on this! I think it is something to do with intermittent poor contacts between the lens and the body. Do you notice any looseness or play between the lens and the body?

My D800 does not have any such problem with this lens, just the D7000.

I tried cleaning the contacts on both the D7000 body and the lens contacts but it didn't seem to make any difference but you could try this in case it works in your case. If that doesn't fix the problem then I would think you are probably going to have to have it sorted out by Nikon service unfortunately. If so then the idea of an emergency lens hire seems a good one.

Frank

Hi Frank.  Interesting that you have seen something similar.  Like I told Chris above, the lens seems very snugly mounted.  I'm thinking it's probably not a contact problem in my case, as the behavior is totally predictable, and everything performs spectacularly through heavy glass, go figure.  I wouldn't totally rule it out for your own intermittent issue, though.

Thanks for taking the time to consider my problem,

Julie

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windsprite
OP windsprite Senior Member • Posts: 2,563
Update

I did some more testing.  This time I threw the D2H and 70-200 VR into the mix and got the same jittery dancing around and misfocus with all camera-lens combinations, so I'm inclined to think it's "normal" behavior.  I'm guessing that it's hard for the camera to find enough detail to focus on when the subject is relatively small in the frame, so the AF is forced to hunt back and forth, and the issue is compounded by the difficulty of keeping a telephoto lens perfectly steady.

Right after I finished testing, the Nikon rep called to say she tried their 300/4 on similar subjects, got the same behavior, and came to the same basic conclusion.

She said she still wanted to take a look at my lens, along with one of the bodies, but there's so little time before my trip that I said I'd take my chances with what I have now and maybe visit the service center again once I'm back.

I think the AF will be OK for the eagle BIFs, which are my main interest.   I'm not entirely satisfied with the above explanation, though, as it seems like the DOF should be deep enough at these distances that the camera wouldn't need to grab onto fine detail.  I also don't understand why shooting through windows seems to work so much better.  So I'm still interested, if anybody has more input.

Julie

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windsprite
OP windsprite Senior Member • Posts: 2,563
Sample images

door open

door closed



door open



door closed



door open

door closed



top, door open; bottom, door closed

Edit:  all the images were taken with the D300, 300/4, and 1.4x teleconverter at f/5.6 and 1/1000".  The ISO varies, as I was using manual mode and auto ISO, but it was 200 or 220 for most of the images.

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j_photo Veteran Member • Posts: 3,487
Re: Sample images

No idea if this could be a factor, but many modern glazing units include coatings that selectively block or reflect certain wavelengths. Depending on the type of glass, either the UV or IR components of daylight could be significantly reduced coming through the glass. Maybe this change in mix of light frequencies is affecting focusing.

Have you tried putting a filter on the lens? Maybe that would help.

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windsprite
OP windsprite Senior Member • Posts: 2,563
Re: Sample images

j_photo wrote:

No idea if this could be a factor, but many modern glazing units include coatings that selectively block or reflect certain wavelengths. Depending on the type of glass, either the UV or IR components of daylight could be significantly reduced coming through the glass. Maybe this change in mix of light frequencies is affecting focusing.

Have you tried putting a filter on the lens? Maybe that would help.

Hi.  Very interesting!  Yes, that's a possibility, and I believe our windows are UV coated.

I did try a good Kenko UV blocking filter against the lens yesterday, but it didn't make any difference.  I've been trying to think of other materials around the house that I can try.

BTW, I forgot to mention that the sample images are all 100% crops, if it wasn't obvious.

Julie

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Marianne Oelund Veteran Member • Posts: 7,321
Relax, you do not have a problem!
4

windsprite wrote:

Hi. Very interesting! Yes, that's a possibility, and I believe our windows are UV coated.

I did try a good Kenko UV blocking filter against the lens yesterday, but it didn't make any difference. I've been trying to think of other materials around the house that I can try.

BTW, I forgot to mention that the sample images are all 100% crops, if it wasn't obvious.

Julie

You are creating a problem by shooting through an open door, from a heated indoor environment, through the high temperature gradient to the cold outdoor air.  It's the turbulent air at the open door which is causing the AF jitteriness and inaccuracy.

If you go completely outside, close the door behind you, move away from the building and try your AF again in an entirely cold environment, I'll bet the problem goes away - especially if you let the camera and lens acclimate a bit to the outdoor temperature.

Have a spectacular trip next week!

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Qualities possessed by humans in infinite proportion: Ignorance.
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windsprite
OP windsprite Senior Member • Posts: 2,563
Marianne strikes again!!!

Marianne Oelund wrote:

You are creating a problem by shooting through an open door, from a heated indoor environment, through the high temperature gradient to the cold outdoor air. It's the turbulent air at the open door which is causing the AF jitteriness and inaccuracy.

If you go completely outside, close the door behind you, move away from the building and try your AF again in an entirely cold environment, I'll bet the problem goes away - especially if you let the camera and lens acclimate a bit to the outdoor temperature.

Hi Marianne.

You should have named a figure for your bet ... but then, I wouldn't have had the guts to bet against you anyway.

You were absolutely correct!

I did consider the indoor/outdoor heat issue the other day, and I stepped out onto our 2nd floor deck to do some test pics, but they were still blurry. I must not have gone far enough away from the house, as the deck is snowy where the heat from the house hasn't melted it, and I didn't have shoes upstairs.

I repeated the test a few minutes ago (this time with boots and coat on), and it was just as you said. The jitter stops completely when I go a couple of meters away from the house. Focus is spot on.

The camera and lens have been in a cold room all night, which may have helped as well.

Hoo, what a relief.

Thank you, thank you!

Have a spectacular trip next week!

I'm sure I will now. (If I can get rid of this cold.)

Julie

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Big Ga Forum Pro • Posts: 18,622
I have a solution

windsprite wrote:

door open bad ... door closed good

Have you considered taking the door with you on your trip?

Big Ga Forum Pro • Posts: 18,622
Re: I have a solution

Big Ga wrote:

windsprite wrote:

door open bad ... door closed good

Have you considered taking the door with you on your trip?

Thinking more on this, I'm sure it would fit into your handbag without too much difficulty .....

bikinchris
bikinchris Forum Pro • Posts: 21,531
Re: Marianne strikes again!!!

That was good thinking, Marianne.

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and formal politeness provide lubrication where people rub together.
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xrdbear Veteran Member • Posts: 3,924
Re: Marianne strikes again!!!

bikinchris wrote:

That was good thinking, Marianne.

Also great memory as well I think. This identical problem came up once before with someone taking test shots through an open upper storey window in the city and in the winter. It must have been at least 4 years back.

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FrankG Senior Member • Posts: 1,840
Re: Relax, you do not have a problem!

Marianne Oelund wrote:

windsprite wrote:

Hi. Very interesting! Yes, that's a possibility, and I believe our windows are UV coated.

I did try a good Kenko UV blocking filter against the lens yesterday, but it didn't make any difference. I've been trying to think of other materials around the house that I can try.

BTW, I forgot to mention that the sample images are all 100% crops, if it wasn't obvious.

Julie

You are creating a problem by shooting through an open door, from a heated indoor environment, through the high temperature gradient to the cold outdoor air. It's the turbulent air at the open door which is causing the AF jitteriness and inaccuracy.

If you go completely outside, close the door behind you, move away from the building and try your AF again in an entirely cold environment, I'll bet the problem goes away - especially if you let the camera and lens acclimate a bit to the outdoor temperature.

You could be right, although she did originally say:

"Then yesterday I took it out on our deck and tried shooting some objects around my house (I have a cough and fever right now and can't venture out into the wilderness to test this thing). I live right in the city, so my subjects were urban junk like TV antennae, electrical poles and insulators, crows, airplanes, etc. ..."

I'd assume "out on our deck" means outdoors (that's what it would mean in the UK!)?  So I'm not sure how that is shooting through a high temperature gradient?

As I mentioned I have encountered what at least sounds superficially like a similar symptoms with my 300 AFS in use with my D7000.  just as bad even with either a 1.4 or 1.7 TC fitted.   I have put it down to an intermittent contacts problem between the lens and the D7000 as I can make the problem temporarily go away either by exerting a slight twisting force on the lens barrel or by tilting the camera significantly upwards (as if shooting birds in flight for example).  By contrast the same lens works fine with my D800 - no sign of the problem at all.

Anyway let's hope you are right!

Frank

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