Showing posts with label Focus. Show all posts
Showing posts with label Focus. Show all posts

Wednesday, July 21, 2010

Don't use the focus limiter feature of long lenses

From http://natureandwildlifephotography.blogspot.com/

There was a time that I always used the limiter. Now pretty much never.

Green Heron w/ fish

This guy wouldn't let me approach close at all. If I tried to walk towards him he'd fly away at 50 feet! After that happening twice, the next time I saw him at more than 50 feet, I laid down and waited for him to come to me and he did. The above is at about 40 feet. He got to inside of 10.

One of the reasons I now do not use the focus limiter at all on my telephoto lenses is that shots of far away stuff is easy, and I want close stuff. When the close stuff presents itself I do not want to be fumbling over a limiter switch. It makes the lens hunt more, or spend more time hunting through the range of focus - but it is one of the things I've changed in my approach to focus in the last year. I'd much rather miss the far away stuff than the close stuff.

With birds close often happens in just a few wing beats. For the above I was prone and trying to balance the lens, not show myself to the heron, and keep shooting as he kept getting closer and closer...

There's nothing much more frustrating then hoping and trying for close encounters and then having the camera or lens get in the way of taking those close photos...

FB / twitter

--50--
Nikographer.com / Jon

Saturday, July 10, 2010

Gear - multiple bodies

From http://natureandwildlifephotography.blogspot.com/
I try not to write about gear too much. Gear should work, not be the focus of major thought or discussion, and be the tools used to do something - take images.

There's a funny reply to the comment "wow great photo, what kind of camera do you have?" - something like "would you ask Shakespeare what of kind of pen he had?" The tools play a part, but they don't do the thing, they don't automate the making of great images.

Time and effort is best spent focusing on learning about subjects, locations, photographic techniques. Time should be spent researching, appreciating the work of others, and trying to grow as a photographer.

All that said, I just read a very good review by Thom on the 200-400mm VR lens. And then just a day later I read the very brief (too brief in my mind to really count for a review) of the new 200-400mm VR2 lens by Trey.

read more...

I agree with pretty much everything Thom said about the lens in his review. Great lens, and have issues, and struggles at 400mm for long distance shooting, and struggles even more with converters. But close up to medium distances it is great. Thom also noted much of the time he used the lens he used different bodies, as new ones became available, and very often got varying results.

DSCN0707
Having Multiple Bodies
There are multiple benefits to having more than one Digital SLR. The most obvious of which is that you can be out shooting and have two lenses mounted and ready to go. One might have a short zoom, and the other a long telephoto. Like I said, that's the most obvious of reasons to have 2 cameras.

Assuming the cameras are from the same manufacturers (same lens mount), and might share the same batteries (like many Nikons) - there's the benefit of swappable batteries, multiple chargers, similarities in menu systems and controls, etc.

A second body is also great as a backup. Most of the time you can only shoot with one camera at a time, so, you only really NEED one camera, which makes the second camera often best thought of as a standby in case the first camera breaks, fails, dies, etc. I've bought 5 digital SLRs and more than a couple times I've had to send one in to be repaired. Actually, I never send the D70s in to be fixed. It has trouble writing to the memory card, and some times writes jibberish. The D200, D300 both went in for focus issues, and the D300 more than once. The D300 actually also had a sensor die that detects the state of the mirror (it would stick UP).

In reading Thom's review, and remembering some of the problems I've had with gear, it reminded how good it can be to have a second body. Focus performance can be a very frustrating thing to investigate. Thom said that for his 200-400mm lens the major thing regarding focus was the body, not the lens. I agree.

Last year I wondered and worried about my D300 and 200-400mm VR and the focus or lack of focus performance I was getting. As part of that I wound up going back to shoot with my old D200 and was shocked to discover that the D200 was working better for fast focus tracking.

I sent the D300 in to be "fixed" and they tuned it, cleaned it, and also set everything to the opposite of how I had it (release priority, small jpg, 9-point, blah blah).

Recently I've been using my D300s and have had some strange focus problems. With the 200-400mm I've had it hunt briefly for focus, and then give up. I scratched my head for a while, and then tried the D300 and the problem went away, it was working properly. Most likely for my issues with focus it is my gear and it is that I let my gear get dirty and I push my expectations to where I should probably get a pro level body like a D3...

So, my post was motivated by this discovery, and I finally got to the point. Having more than one camera to use allows for an entirely different set of tests you can try to see if it is you, or the lens, or the camera, or the conditions you're shooting in, or maybe nothing is wrong and everything is behaving as best as can be expected. With one camera and a problem, you might never be able to figure it out, because you have no other camera body to make a comparison to.

Focus problems with a pro-sumer level dSLR is a very common thing. I've had questions and some times actual focus problems with all my gear - as early as with the D70s and Tamron 18-200mm. Back then it was me, and my novice ways. I didn't understand focus, auto-focus, and it works be "Seeing" contrast. Try focusing on the sky or a brightly lit white wall without features - there no contrast and the camera will hunt and find nothing. Auto-focus works by seeing a change in brightness levels (contrast) and adjusting the focus until there is a sharp or distinct transition (my un-technical description). Cameras use two type of focus sensor, straight-line sensors and 2 perpendicular straight-line sensors grouped together as one.

That's auto-focus 101. When things start to get complicated is for moving subjects, placement in the frame, the direction of the movement, the speed of the movement, and the settings and horsepower of the camera itself. Trying to figure those things out and what works best and when isn't easy.

Skyway Robbery Pt 8 (plus animation)
Being able to rule out a faulty or dirty or mis-configured or mishandled camera and lens is a huge thing. Not everyone will push their gear to the limits. I don't travel to Alaska or Africa, or other exotic places, but I do seem to push things.

Birds in flight or sports are probably a couple of the most demanding focus situations to shoot in. And birds are probably harder since they are small and can move in all directions while for most sports the subjects remain on or close to the ground.

If you are upgrading to a newer camera, keep the old one. If you have a good camera now, consider buying another lesser one, used, and keep it around as second to shoot with or test things out when you run in to problems.

5 years ago I felt I really spend a lot and was done buying gear when I bought my first dSLR, a D70s and a single lens. That was 2005, now it is 2010 and I shoot with 3 bodies often taking 2 out on a day. The Fuji S5 is great for high dynamic range shooting and makes a nice landscape camera. For everything else I use either a D300 or D300s, and usually it's the D300s since I can switch to video.

Nikographer.com / Jon

Thursday, April 29, 2010

GBH and MD Osprey - GVP #14 #15

From http://natureandwildlifephotography.blogspot.com/2010/04/gbh-and-md-osprey-gvp-14-15.html

10 days in and about 15 vertical shots posted so far...


GBH Dippers

I've been shooting vertically more for sure. Yesterday I went to shoot some birds and actually tried some in flight shots vertically! It was weird and a little awkward, but it was good.

MD Osprey


Vertical flight shots worked best for the part of their flight where they'd bank in front of me to the left or right.

Focus
Keeping the manual focus ring locked down seems to avoid the problem where the camera stops trying to auto-focus if it moves.

Last night I experimented with intentionally setting the focus fine tune to -6. Very often I've shot an osprey for example and gotten the wings in focus and the head (which is slightly closer to the camera) is not in focus. The test seemed to work, and I will try again with something like -10 or -12. Flight shots with the subject closing in on the camera seem to be when this problem happens most.

I hedged my bet and shot with that setting for only a portion of my time out. The results seem to indicate it helped. My only fear for this is I will forget I had it set and then shoot something not moving and my focus will all be off slightly.

-50-
Nikographer.com / Jon

Monday, April 26, 2010

GVP 8, 9 and 10 - and focus plan

From http://natureandwildlifephotography.blogspot.com/2010/04/gvp-8-9-and-10-and-focus-plan.html

BCNHBCNH

I've been on flickr now for so long I've been shooting and posting with it mind. Too much on my mind.

This Vertical project is one attempt to break that habit. Explorer doesn't "like" vertical shots, and I don't as much, and laptops, contacts, screens, all favor horizontal images.

Whatever.

Another thing I have gotten in to the habit of it posting one a day mostly. So tonight I decided to post 3 shots, all vertical.

Yesterday it was vertical video.

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On a more technical note, I learned something about hand holding my 200-400mm.

My main pet peeve with the 200-400mm f/4 lens is that the manual override of focus cannot be turned off. Gripping the lens near the front very very often caused the focus ring to turn and then that causes the camera to stop trying to focus.

I thought about using some gaffer tape to lock down that ring. But tape on that lens, just didn't seem like the right thing to do. This weekend I had the idea to slide my neopreme camo back a bit to cover the edge of the focusing ring, to prevent it from moving at all. It seemed to work!

Two other things I've changed up to improve my focus tracking of moving birds is to use the focus button on the back of the camera. The general way is to focus with the shutter button or back button on a moving subject and then just keep the rear-focus button depressed all the time. Take shots, wait, continue to track, take more shots - doing it this way keeps the camera working on focus the entire time because the focus button on the back of the camera is still pressed...

The other thing I finally did and think I may just stick to is I've turned OFF the focus limiter. I've gotten better at getting close to birds, or hiding better, and I don't want to miss those closer chances. With the limiter on I've had the occasional very close fly-by not be shootable because the lens wasn't allowed to focus so close.

The focus limit trade off - allow the lens to focus faster for a far away subject and miss close shots. OR take far away shots after a little lag / hunting, but NOT being locked out of the chance to focus close - which on the 200-400mm is about 6 feet (minimum).

The other day I was out shooting in two spots and had an eagle (both times) spot me late and make a hard turn and bank away. I was hiding and dressed in some camo, but not in a blind at the time.

-50-

Nikographer.com / Jon