Advice on picture required.

I am trying to find out why my pictures are not achieving a good rate of focus sucsess, despite shooting with a good dissipline of good light, enough shutter speed, IS working fine, and servo, could the slight oof be a result of focus front or back focus Issues? or just a lens lack of deffinition.
The picture was a crop about 45percent and was a raw Image with pp done In DPP with sharpening added especialy, so any Ideas what might be causing this?

P.

Pagman wrote in post #15719328
I am trying to find out why my pictures are not achieving a good rate of focus sucsess, despite shooting with a good dissipline of good light, enough shutter speed, IS working fine, and servo, could the slight oof be a result of focus front or back focus Issues? or just a lens lack of deffinition.
The picture was a crop about 45percent and was a raw Image with pp done In DPP with sharpening added especialy, so any Ideas what might be causing this? P.

Several miles of atmospheric distortion will not help any autofocus system. With the atmosphere in the way, conventional focusing may not be possible.

Probably caused by a cruddy lens and shot too far away.

Take Care,
Cheers, Patrick

Saint728 wrote in post #15719435
Probably caused by a cruddy lens and shot too far away.

Take Care,
Cheers, Patrick

nifty 250 In excellent condition on my 30d....

P.

You cant expect a subject that far away to be pin sharp, there is atmosphere to deal with, as well as just the limits of the technology. A longer lens will help, it will get you closer to the action.

I would try to shoot something closer within a few tenths of a mile and not something that gives you 4-5 miles of cruddy air between you and the subject.

Try shooting birds in trees, people out for a walk, a car driving down the road, etc.

Too far away and way too much atmosphere to go through to get a much better shot than you got as well as good autofocus. Your target is so small that you are trying to focus on that there may be too little area of contrast to give the autofocus enough area to focus on.

Thank you all for the comments unfortunatly with my bulk of pictures being this kind of subject, I am stuck abit and I kno a longer L lens would help probably alot, but just not In my league, the best alternative price wise I have seen Is a 50-300 IS L but again alot more money than I have, mind you I guess the extra bit of reach and an L series lens would help abit with cropping.....

P.

If the bulk of your pictures will be subject material miles away, then yes, you will need to re-evaluate your lens line-up. However, again, no lens is really going to fix the issue of miles of atmospheric haze, it just means a longer lens is going to produce a blurry enlargement.

TeamSpeed wrote in post #15719580
If the bulk of your pictures will be subject material miles away, then yes, you will need to re-evaluate your lens line-up. However, again, no lens is really going to fix the issue of miles of atmospheric haze, it just means a longer lens is going to produce a blurry enlargement.

Thank you for your guidance mutch appreciated, I think I get my Insperation from a few posters on the transport section, one Inparticular takes Extremely sharp pictures of airliners several miles up, and from what I have read the equipment used Is 400-500L lenses with a 2 X on picture size high quality Images, without any air quality problems smoe even show the registration and fine under wing details on a plane 6 miles up...

P.

Air quality can change from one hour to another. Usually the colder the environment, the clearer the air will be. The other element, as you have defined, is the lens. I like the 55-250 alot, but its strong suit certainly isn't for resolving detail from objects really far off.

A 100-400L is a good choice, one of the long Sigmas would work, like the 150-500 or 50-500. I would suggest trying to budget for one of those in the future.

Yes but I think the problem is that the aircraft in question in his photographs are not actually at 20000 feet plus, but much lower, in and around the airport. Also being in Canada in the winter probably helps, as the air quality is likely much better. The 100-400L is very good but even "only" 20000 feet is 3.8 miles away, some air liners may even be closer to 40000 feet, and you would not consider trying to photograph something the size of a jet liner from 3.8 miles away if it were on the ground, let alone nearly 8 miles.

Alan

After I posted I noticed that you have a 30D, which is "only" 8 Mpix, that reduced resolution is also going to be a big problem compared to the much higher sensor resolution that is being used in the photos that you have been looking at. Even with 400mm you will not have enough pixels on target to get a good image, 250 or 300 will just not be anywhere close with that camera, you would really want something closer to 800mm with a 30D.

Pagman wrote in post #15719631
Thank you for your guidance mutch appreciated, I think I get my Insperation from a few posters on the transport section, one Inparticular takes Extremely sharp pictures of airliners several miles up, and from what I have read the equipment used Is 400-500L lenses with a 2 X on picture size high quality Images, without any air quality problems smoe even show the registration and fine under wing details on a plane 6 miles up...

P.

As an example of the quality I am on about that can be achieved....Pic courtosy of a regular transport poster...

P.

Pagman wrote in post #15719716
As an example of the quality I am on about that can be achieved....Pic courtosy of a regular transport poster...

P.

What altitude was the aircraft at, and in what part of the world? It being an Emirates plane, it may well have been shot in the desert middle east, which would help atmospheric conditions enormously, compared to more humid places. I also have a hard time believing that was at more then 10k to 15k feet. (3km - 5km).

archer1960 wrote in post #15719742
What altitude was the aircraft at, and in what part of the world? It being an Emirates plane, it may well have been shot in the desert middle east, which would help atmospheric conditions enormously, compared to more humid places. I also have a hard time believing that was at more then 10k to 15k feet. (3km - 5km).

Its just a pic I have pinched to show, the owner I believe lives In Holland where the pic was taken, It was supposed to be at about 30,000ft over flying Amsterdam enroute to London Heathrow taken with the eqv of a 1000mm lens (35mm eqv)

P.