Is my use of a filter(UV) contributing to difficult focusing?

[Ken MT]

You might like to look at this review for your lens from 12 Aug 2011

http://www.bythom.com/sigma-150-500mm-lens-review.htm

[C24]

_LN71287_edited-1 by FuzzyFastjetFotos, on Flickr

I am just testing my IT skills here folks, investigating how this lovely Forum operates. My thanks to everyone who posted comments, above. I read and digested them, then during the summer this chap came down the runway & absolutely blew me away with a stunning piece of flying. This is all that I could capture but it triggers in my mind the whole sequence of maybe 30 seconds. If you have never flown this is just a bad snap.

Here goes my First post

Charlie

[Dave Humphries]

I am just testing my IT skills here folks, investigating how this lovely Forum operates. My thanks to everyone who posted comments, above. I read and digested them, then during the summer this chap came down the runway & absolutely blew me away with a stunning piece of flying. This is all that I could capture but it triggers in my mind the whole sequence of maybe 30 seconds. If you have never flown this is just a bad snap.

Here goes my First post

Charlie

Hi Charlie,

Welcome to the CiC forums from me.

Looking at the EXIF data for your "fuzzy fast jet", I'd suggest f/16 and 1/250s at iso 320 (on a Nikon D800 at 400mm) might have been better as f/8 and 1/1000s at iso 320, or faster still on shutter speed and trade another aperture stop and/or raise the iso.

I have to wonder why that aperture choice? (e.g. accidental)
Used on all D800 shots of the F15.
Or related to the thread title perhaps.

I noted you used f/11 or f/8 on the 300mm lens fitted to the Pentax K100D for the Nimrod and Harrier, getting faster shutter speeds and sharper shots.

Cheers,

[rpcrowe]

Hi Charlie,
Just a thought. Are you using A/F on these shoots?
It strikes me that the autofocus may not be quick enough for jets doing 500MPH @ 600 feet. I'd be inclined to turn it off and pre-focus (Infinity should be fine) and just concentrate on panning.
On that last point, I presume you are following through on the pan (little golf trick there).

We photographers like to consistantly spout the adage that it is not the gear, rather the photographer that makes images great. While that may be true for the normal run of the mill image aquisition, it is pure hokem when you are pushing the envelope of capabilities...

Birds in flight as well as aircraft in the air require fast accurate autofocus from both camera and lens. There are some cameras and lenses which, although are just fine for more mundane shots, do not have the fast focus capability needed for the birds/aircraft imagery.

I don't know about the focusing capabilities of your K7 and 150-500mm Sigma lens. I do know that the Canon 400mm f/5.6L lens has exceptionally fast and accurate a/f capability even on less than optimum cameras. The following image was shot using the 400mm f/5.6L lens on an older Canon 10D camera. This hydroplane was crossing the camera position at over 150mph fairly close to my camera. The 400mm f/5.6L lens nailed the focus despite being used on a less than premium camera...



The focus on this shot was a bit more critical because the boat was approaching the camera at an angle...



More images of these Thunderboats acquired with the 400mm f/5.6L on a 10D camera can be found at...

http://rpcrowe.smugmug.com/Sports/TH...8016&k=pmbf79N

BTW: I don't know about the K-7, 5Diii or 1Dx series of camera but the Canon 7D has many adjustments to the autofocus which will help it focusing in on fast moving subjects in various types of venues. This is the camera that I would use for any action shooting. (of course I would - this is the camera that I own!) However the K-7, 5Diii or 1Dx may be even better but, the 7D suits me just fine...

Finally, I tend to use a higher ISO when shooting fast moving subjects. In fact, I have one set of parameters registered on my User Selected Modes especially for fast moving captures. The higher ISO will allow a faster shutter speed and or a smaller f.stop...

[jcuknz]

From my limited experience of photographing moving things, have yet to go to a digital age air show, I have a hunch that my problem with using a lesser camera without the marvelous follow focus feature that I tend to wait for the focus confirmation light to come on and then there is a pause until I press the trigger ... during which period the subject moves out of focus ... just a hunch and I have always assumed I have a quick reaction time Some cameras have focus priority mode where the camera doesn't shoot until it finds focus.

Awhile back when I bought my DSLR to use my legacy lens, amongst other things, I tried [ had to] shooting manual focus with quarter scale jet boats and teethered craft and was largely unsuccessful. Being scale models they tend to go relatively faster than the fullsized versions.
One that didn't get away

[jcuknz]

Charlie .. pardon me but do you like this better? some sharpening and adjustment of curves layer in editing [ I use Paint Shop Pro but Adobe Elements could do similar ]

With second thopughts I selected just the nose and cockpit and sharpened it once again.

I'm sure you could do better with the original file
If you don't like the white fringes then you can clone across a very small amount of sky to cover then using a one or two pixel tool ... slow and tedious and only for ones best shots

[rpcrowe]

From my limited experience of photographing moving things, have yet to go to a digital age air show, I have a hunch that my problem with using a lesser camera without the marvelous follow focus feature that I tend to wait for the focus confirmation light to come on and then there is a pause until I press the trigger ... during which period the subject moves out of focus ... just a hunch and I have always assumed I have a quick reaction time Some cameras have focus priority mode where the camera doesn't shoot until it finds focus.

Regarding the comment which I have placed in bold. Here is some quite interesting information regarding the different methods of A/F with the Canon 7D. See pages 4 and 5 of this link concerning the Custom Functions III 1-4. I could not understand C.Fn. III-2 by reading the owners manual. However it is pretty clear with this explanation...

http://cpn.canon-europe.com/content/...s_explained.do

[Bobobird]

I will chip in from a birder's point of view.

A plane is hell of a lot bigger then any bird so getting focus should not be an issue. Planes are definitely faster but that becomes relative because of their much bigger size.

For birds my startup settings are always - iso 800, 1/1250. f5.6-f8. Adjusting as/when needed for intensity of light and varied backgrounds. IS off in most instances for flight shots though sometimes it is on when shooting static birds and suddenly you have to turn to grab a bird in flight. As long as your focus technique is reasonable IS interference is really not all that big a deal. For planes, just turn IS off.

Equipment - as Richard says. 7D + either the 300/f4 or 400/f5.6. The latter does not have IS so if you want both 400 and IS get the 300 and slap on a 1.4TC. The IQ differences are too small to notice. You could even use a 2xTC though that will lead to some IQ loss and less AF sensitivity.

7D vs lesser 1.6 crops - consider the really fast burst rate vs the much slower fps (RAW) rate of the others. If you shoot JPG, does not matter but a 7D a much better camera due to its really good AF system and burst buffer space.

Full frame vs crop - go with the crop. The current crops have good noise tolerance up to ISO800 (including the 7d). A full frame does have a better noise floor at much higher ISOs. However airshows is a daytime thing (like birds) so use of extremely high ISOs should not be necessary.

Lens - if you need a variable range then there are either the 70-200/2.8 II or the not that heavy 70-300L. These 2 are the sharpest Canon zooms in this range at this time. The earlier versions are great too but the new ones have this new awesome IS. (I can get sharp shots even a 1/15 hand held and I am not the steadiest at the best of times.)

TCs - bear in mind that crop + TCs + zooms will result in slightly softer images. Using a crop + primes + TCs, the IQ loss is imperceptible.

Tripod/monopod - not quite needed as the setup is not all that heavy. You get better stability just leaning against something.

If going the 300 or 400/f2.8 route then a tripod/gimbal head is your friend as these lens are really heavy.

Hope this helps.

[rpcrowe]

I would like to throw in another possibility... I have fabricated a shoulder mount rig for long lenses which supports the camera but, which makes following moving subjects a lot easier than when using a tripod or even when using a monopod. I made this using about ten U.S. dollars worth of materials that are available at any home improvement store. The tools I used are all common hand tools with the exception of an electric drill. The BushHawk rig is also a good stabilizer but, my rig is more stabile since it rests "on" your shoulders rather than "against" one shoulder.



Details on fabrication as well as a materials list can be found on my smugmug site at:

http://rpcrowe.smugmug.com/Photograp...2948&k=477SCcC

I originally fabricated this for use with heavier and longer lenses which I will occasionally rent. However, it works great with my 400mm f/5.6L: lens and partially makes up for lack of IS in that lens...

The rig easily breaks down for convenient transport and weighs around two pounds (~1 kilogram). It could also be fabricated using aluminum tubing...

NOTE: The exceptional image quality of the 400mm f/5.6L lens wide open also helps since I can use the fastest shutter speed possible!