Panning Motor Racing (back of car out of focus?)

[T_O_M]

Took some photos of some Historic Motor Racing on the weekend, did a lot of experimenting with slower shutter speeds. I am interested in peoples opinions on this photo of why the back wing is out of focus. Panning shot taken when car was in front of me (90 deg) and it was travelling in more or less a straight line, EOS 10D, 28-200mm lens, ISO 100 1/125 sec f6.7. I would think the whole car is in the same focal plane so this can not be DOF. Is the back out of focus due to the shutter speed and the panning motion or is it the lens? I don't think it is vibration of the wing as I had a few pics of road cars with the same effect. I have posted this on another forum without a answer, I am interested in people opinions in this forum.

Thanks Tom.


http://www.bytephoto.com/photopost/data/500/928101_0135.jpg?5721

[maderito]

Motion in the photo that cannot be minimized by panning is most "out of focus" -- engine and airfoil vibration, wheel rotation, etc. I would think these problems would be most exaggerated over the wheels in the back of the car (as in an airplane).

I'm curious what others have to say.

[TimNYC]

I agree with maderito. It's not the panning technique. The wing is probably vibrating like crazy, causing it to be oof. Excellent panning technique, Tom!

[Mark Kemp]

Yep

The wing is not out of focus it is vibrating up and down and the shutter speed is slow enought to show it as blur.

That thing is a great big plate held up by one thin bracket and its bolted to an internal combustion engine while travelling at racing speed. Some vibration may be expected.

[EXA1a]

[quote]T_O_M wrote:
Took some photos of some Historic Motor Racing on the weekend, did a lot of experimenting with slower shutter speeds. I am interested in peoples opinions on this photo of why the back wing is out of focus. Panning shot taken when car was in front of me (90 deg) and it was travelling in more or less a straight line, EOS 10D, 28-200mm lens, ISO 100 1/125 sec f6.7. I would think the whole car is in the same focal plane so this can not be DOF. Is the back out of focus due to the shutter speed and the panning motion or is it the lens? I don't think it is vibration of the wing as I had a few pics of road cars with the same effect. I have posted this on another forum without a answer, I am interested in people opinions in this forum.

Thanks Tom.
quote]
Great shot!
Two questions: what focal length was it shot with and did you use a tripod or monopod?
--Jens--

[defordphoto]

When it comes to shooting motorsports that's very common and I never let it bother me. Since photography's gone digital it seems that everyone is so, so obsessed with sharpness.

Heck there's some times when I'm shooting the Jet Sprints that I'll dial down my speed as slow as 1/15 for a wild blur effect to show action. I love playing with that and some times the shots turn out awesome! Most suck and are unusable, but the ones I get rock. At least I think so. You usually get about 1 out of 15 that are decent.

So, with that being said...That shot is awesome Tom! Frame it!

[Belmondo]

Tom:
Do you have any idea how thrilled I would be to take a picture like that? There isn't a single thing wrong with it, so be proud. You done well.

Tom Too

[sdommin]

Looks to me like this effect was caused by camera shake. In other words, the shutter curtain was moving across the CCD. When the shutter curtain was at the front and middle part of the car, the camera movement matched the car movement. But when the shutter curtain got to the rear of the car, the camera movement and car movement were slightly different. This could easily happen, since the camera was handheld, the car was moving, and the shutter speed was relatively slow (1/125 sec.).

[boBquincy]

Since the front of the car is in focus this is obviously a case of 'front focus', your camera is a lemon and you should sell it to me cheap! ;)

Mine has 'rear focus' since the rear of this car is in focus.
Actually, I was lucky to get it in the frame at all! ;) This 'vintage' ex-Michael Schumacher car was *so* fast it set a track record within a few laps!!!
The photo was taken at Virginia International Raceway's SVRA event in October, a great event for car enthusiasts (and photographers).

http://mindspring.com/~bobquincy2/vehicles/CRW_5198_800.jpg

[T_O_M]

boBquincy,

My shot can not be front focus because the car is more or less straight in the focal plane. Your shot car is on an angle and therefore back focus or focused with one of the left hand side focus points. I am very happy with this pic and I have framed it. I was just interested in people opinions on possible causes. I was using a monopod which helps a lot with long lenses, slower shutter speeds and panning. Here is another pic with the same effect. Maybe it is vibration as a few people have metioned.

Thanks Tom.

http://www.bytephoto.com/photopost/data/500/928100_0035.jpg?2400

[IndyJeff]

T_O_M part of your problem is the slow shutter speeds. I shoot race cars too, generally around 200MPH. One thing I have found is the slower the shutter speed, the softer the pic. As a general rule I will shoot 1000@8.0 / 400, of course sometimes conditions won't allow that. Some of the worst pics I ever took were at Indy during the race when it clouded up a few years back and looked like rain. I think I was down to 350 on shutter speed. Cars looked good until you started looking at the smaller stickers.
Of course from the pic you posted I don't think your subjects are moving quite as fast as mine are so you can use a slower shutter speed. Still I wouldn't go under 500. Maybe some others will have some comments to offer on my advice.
I know the discussion of shutter speed has come up when we are on break or after the day is over and the general concensus seems to be, open it up as the light goes away and keep the shutter as fast as you can.
What I look for in my pics is the smallest of sponsor stickers on the car. If they are sharp then the pic is good.

Email me at IndySportPhotos@aol.com and I can send you a sample of what I look for in a good and a bad shot.

[T_O_M]

IndyJeff,

I don't like shooting at higher shutter speeds as I find the pictures look static. This day I shot between 1/60 and 1/350. I've only had my 10D for a month and this was my first chance to shoot some motorsport in digital. I have shot Formula 1, V8 supercars with film but I could never expirment as much because of the price of film and developing. With F1 I've gotten excellent results at 1/350 and resonable at 1/250. But now I can practice a lot more and delete what does not turn out. Bring on next years Australian F1 GP.

Tom.

[IndyJeff]

Tom if your just shooting for yourself, the slower shutter speeds will be fine but, if your trying to sell your pics you want the sharpest image you can get.
In the first pic you posted, the out of focus parts on the wing are probably not due to "wing shake" as some have suggested. I don't want to judge entirely on a pic posted on the web, I know how quality can be lost due to upload times, but the stickers all over the car are soft. You are not going to get each and every sticker sharp as a tack but the larger ones should be much clearer than that. The smaller the sticker, the more distortion you will have and the higher the subject speed, it only gets worse.

The movement will still be seen in the wheels up to 1500 shutter speed at 200 MPH, sorry you will have to convert that to your metric system LOL

[IndyJeff]

Well here is one of my shots from Chicago last Sept. during the IRL race.


http://www.savepic.com/freepicturehosting/is.php?i=19420&img=Schecter-Herta-Hornish-Chi03.jpg

[T_O_M]

IndyJeff,

I understand your point of view where your comming from. My shot was taken at 1/125 so of course the image is not going to be razor sharp and I am only using cheap glass from my film SLR (28-200mm lens & 75-300mm II). Like you said it might be OK for my own use and it is, photography is only a hobby for me. I like your pic but to me the wheels are not blurred enough as I can see the spokes in the rim still, but this is only my opinion so please don't take this the wrong way.

Regards Tom.

[defordphoto]

The thing is that if you pan properly the 1/125 speed will produce a crisp photo. It's tough to do and you'll get a bunch of throwaway photos, but it is possible. Like I said, I have panned successfully as low as 1/15. And I disagree that a photo has to be 100% sharp to sell. Some of my most popular photos are the ones that may be somewhat 'blurry' to show that the vehicle is actually moving.

That being said, I also shoot at 1/1000, 1/2000 and above to for that perfect, sharp photo. I use many methods for my motorsports shoots to produce a wide variety of photos.

[IndyJeff]

Take it the wrong way? Oh no T_O_M, you are right. Everyone shoots what they like the best, and there is nothing wrong with that. I didn't mean to imply that your "doing it all wrong" when in fact that's the effect you want, so it is right. Right? LOL
RFM is right that you can get a sharp shot panning at 125 but, your going to take a few to get it. I have taken some over the years that the car was sharp in the foreground and the background all blurred. I wish I had a dollar for every pic that wasn't usable tho.
I know you love the idea of digital to be able to experiment without the cost of development, me too.