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Focus Chart

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Pursuant to another thread, it made sense that some folks might not have a focal point on which to set their camcorder focus. Others simply might want something kinda different.
Instructions for using the focus chart are printed on the chart.
You'll likely need to have this printed at Kinko's or other local print shop, unless you can print 11x17 in-house.
I hope it's of use to some of you.

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Thank you for that...

Question though, is "8 feet" too much of an assumption? Or are you basing this on a focal range to cover most skydiving scenarios?

When I used to shoot more manual focus, I would set my distance for about 3 or 4 feet for tandems, 5 or 6 for 4way and up to infinity the bigger the group got.

I'm actually getting good enough results with my current lenses and AF AIServo that I haven't gone back to manual focus for a while now.

Just wondering, thanks!
Lew
http://www.exitshot.com

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with 1/5 imagers and the "average" .3 or .5 lens that most skydiving videographers use, eight feet is a perfect distance that allows for a wide margin of error.
You, on the other hand, don't quite fit into "average."

Remember, this is for camcorders. Using this chart for an APSC or full frame DSLR could lead to a bad day.

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Remember, this is for camcorders. Using this chart for an APSC or full frame DSLR could lead to a bad day.



Can you give us your recommendations for keeping subjects in focus with the DSLR?

I've switched back and forth with manual / auto focus. I've used a single AF point (center one), and I've used all nine AF points. Sometimes the images are sharp as a tack, sometimes they're soft and slightly out of focus. I'm ready to go buy a 7D just because they (supposedly) have improved the AF system.

Got any more affordable suggestions?

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Remember, this is for camcorders. Using this chart for an APSC or full frame DSLR could lead to a bad day.



Can you give us your recommendations for keeping subjects in focus with the DSLR?

I've switched back and forth with manual / auto focus. I've used a single AF point (center one), and I've used all nine AF points. Sometimes the images are sharp as a tack, sometimes they're soft and slightly out of focus. I'm ready to go buy a 7D just because they (supposedly) have improved the AF system.

Got any more affordable suggestions?



The focusing system on the 7D is the same as in the 1DMark4 so its very good! at least they made alot of improvements since the MarkIII.

As for the focusing issue i would suggest pre-focusing on the ground, and shooting at a high aperture!

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I find this text really helpfull (never did calibrate lenses and adjust autofocus myself). On this page you will find link to LensAlign (broken link but still a link :)
P.S.:same company also makes WhiBal which is really cool for post production white balance. Really cool. ;)

EDIT: While we're on the subject of white balance B| can you use the same technique to do white balance post production on a computer using grey card like WhiBal? Does video editing software work this way?
I understand the need for conformity. Without a concise set of rules to follow we would probably all have to resort to common sense. -David Thorne

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Remember, this is for camcorders. Using this chart for an APSC or full frame DSLR could lead to a bad day.



Can you give us your recommendations for keeping subjects in focus with the DSLR?

I've switched back and forth with manual / auto focus. I've used a single AF point (center one), and I've used all nine AF points. Sometimes the images are sharp as a tack, sometimes they're soft and slightly out of focus. I'm ready to go buy a 7D just because they (supposedly) have improved the AF system.

Got any more affordable suggestions?



What camera and what lens? And next question, what settings, and what conditions? Ie, if you're using just about any Canon eos or Nikon DSLR with a f/2.8 fixed lens like the sigma 15mm or canon 15mm, shoot at 1/500s on a clear day, ISO 200 or so, with AIservo turned on your pics should come out sharp, if not, make sure the helmet is steady and most of all keep your head still ;) But most likely your problem is in the setting and/or your lens, something a more expensive camera won't help with, in fact a more expensive camera generally requires MORE knowledge of settings plus a good-quality lens. Although if that's the excuse you're using to buy a very nice camera, :):ph34r:

ciel bleu,
Saskia

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IF you have a good USM lens, I definetly think AF is the way to go. Almost never I would use center point only, because it focuses only on the centre. There are a lot of times the exact centre point would not hit the target and this would cause the AF to fail. (see the pics attached)

IF you have a cheap lens with a bad AF motor, then might be better to use MF. Though even a slow AF lens could be usable if you use a mono switch that makes the camera focus constantly. Focusing on a given distance is a good idea like Teigen said, but then the photos will be sharp only at this given distance. Sure depending on the DOF on the given setup you might end up with reasonably sharp photos most of the times even if you arent exactly always at the given distance. However reasonably sharp isnt ofcourse as sharp as it could be.

One other thing worth mentioning is that when filming tandems for example I like to take a variety of angles within different distances. With MF you wont have SHARP photos at docking distance and sharp photos at 30ft distance on the same jump. Basically you would need to choose which ones you want in beforehand.

(just to clarify, I did use all nine AF points on the example photos and therefore they are both focused correctly)

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What camera and what lens? And next question, what settings, and what conditions? Ie, if you're using just about any Canon eos or Nikon DSLR with a f/2.8 fixed lens like the sigma 15mm or canon 15mm, shoot at 1/500s on a clear day, ISO 200 or so, with AIservo turned on your pics should come out sharp, if not, make sure the helmet is steady and most of all keep your head still ;) But most likely your problem is in the setting and/or your lens, something a more expensive camera won't help with, in fact a more expensive camera generally requires MORE knowledge of settings plus a good-quality lens. Although if that's the excuse you're using to buy a very nice camera, :):ph34r:




I attached one picture from last weekend as an example. I have plenty of other examples at home including one where three shots were taken within one second and only one was sharp. Again I have mixed results, many pictures are sharp but too many are soft (imo).

For this attached pic, here are the specs and settings...
Canon 30D
Canon EF 20mm, f/2.8, USM
Shutter priority 1/400 (might have been 1/500)
ISO 320.
Aperture resolved to f/8
AF Servo
9 focus points selected.

No crop or any other adjustment was done to this picture other than to resize it smaller for upload.



http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&fcategoryid=151&modelid=7301

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Hmm looks from this pic the camera did choose the wrong focus point, that can happen as this is a hard shot for the camera. To try and solve this I would set the camera to high speed (highest fps) and shoot a few pics more on exit, see if that helps, see if the focus shifts.

Also make sure the camera continuously focusses instead of focus-per-shot. My remote (for Nikon D300) is wired so the camera keeps focussing and metering when it's turned on, with a Canon D30 the battery life is good enough that you could do the same IMO, if you're not already.

Other things to check are settings that can lock focus, that's camera-specific and sometimes remote-specific. For example the AE-lock that happened to me when I first got my nikon D80, I set the lens to manual focus and stupid me I turned on AE lock since that's a helpful setting on the ground to re-compose a shot, I also had a remote for it that again was wired to keep metering and focussing when camera is on, this together caused it to get stuck on f2.8 for the entire jump after turning the camera on in a dark-ish plane, oops...

If the wrong focus happens consistently though, and it's consistently to the rear (can't really see how it could be otherwise in skydiving but you never know), you may have a backfocus problem, try a focus chart to be sure (click).

ciel bleu,
Saskia

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The focusing system on the 7D is the same as in the 1DMark4 so its very good! at least they made alot of improvements since the MarkIII.

As for the focusing issue i would suggest pre-focusing on the ground, and shooting at a high aperture!



Canon 30D is what I have now. I think it might be time to upgrade.
Three versions up from 30D (skipping the 40/50D) up to 7D is probably about right. Maybe there will be a 7DmkII released by this spring. Who knows?

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I rarely comment on what cameras are coming out (when I'm aware of them) due to NDA's.
However. I assure you with 100% certainty that there is no 7DMKII coming out next spring nor in 2010 at any time.


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I can't wait to see in the camera in the future with full frame sensor and 1080 24p capability.
-Laszlo-



You wont' have to wait long. :P



Our season is done until spring. It is always fun to see the latest new technology. I suppose the NDA makes it easier to say what is not coming out rather than what is coming soon. Anyway, maybe spring will be time for a new camera. -Cheers.

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