Your opinions on image quality question (1 Viewer)

[seaspirit]

The farther you are from your subject the more atmosphere gets in the way and the more the qualities of that atmosphere influence the IQ. Heat is the big one to watch for - think of the effects of heat haze on the appearance of a scene, but also, I think, humidity, dust and maybe wind or thermal gradients also have an impact. Even things which may not appear visible to the naked eye can become very evident when magnified by a big lens and followed up with pixel peeping.

This will not only impact image quaility, it will also have a huge influence on the hit and miss rate of the AF system.
Ever used a car in the winter as blind and shot through the open window? If the temperature in the car is not close to the ambient outside temperature the warm air leaving the car through the open window will cause the AF to do strange things as it tries to lock on a target. If it does the blurry image caused by temperature turbulence tells the story. Your eye will see very little or nothing of all this going on.

Ulli

 

[mrmarklin]

I personally think that you are expecting too much from your lens setup. There may be some camera movement, in addition to some of the very good observations from others on the forum.
In theory, to stop movement one should shoot to at least the focal length of the lens. In your case that would be a speed of 1120 per second. (500x1.4x1.6 crop factor). You shot @1/6400. But considering the distance to the subject one must realize that this is only a "rule of thumb". My experience has shown that the distance to the subject is a factor in this (yes I realize you have IS in the lens) in addition to some of the other factors noted above. That's why I think a tripod is, next to one's camera, the best tool in the field.

Even some of the better sample shot posted are not 100% sharp. This may be due to atmosphere as well as camera movement.

 

[a.dancy]

Some good points raised above. I agree with Tim as to the things that might cause the soft image.

I photograph birds (mainly peregrines) at huge distances on purpose usually to get them in a particular background. They are fast. The thing that affects the IQ most (apart from speed) is wobbly air caused by differing air density and pollution e.g pollen and dust. However I would also suggest that you check you do not have front or back focus issues or problems with camera lens alignment or lens converter alignment. The converter will magnify faults , so if your lens and converter optics are not clean you will certainly get soft images. I recall taking some images a few years ago and they were all just a bit soft even the close up stuff. I looked at my converter and my thumb print was clearly on it. It cannot be understated that a lot of slightly soft images result from slightly dirty lenses. The dirt just scatters the light. I clean my loptics after every shoot.


Shooting a long distance subject with 700mm FL , ISO 800 and f5.6 is going to reduce your chances of good image quality. I think you should have been on f8. Noise is evident and on a close crop will reduce IQ. IMHO. If none of the advice above fixes the problem then you need to have the equipment looked at.

BTW....It is my belief that you can more easily get a soft converter than a soft lens so try other converters.

Good luck.

 

[a.dancy]

[QUOTE=mrmarklin;2363680]I personally think that you are expecting too much from your lens setup. There may be some camera movement, in addition to some of the very good observations from others on the forum.
In theory, to stop movement one should shoot to at least the focal length of the lens. In your case that would be a speed of 1120 per second. (500x1.4x1.6 crop factor). You shot @1/6400. But considering the distance to the subject one must realize that this is only a "rule of thumb". My experience has shown that the distance to the subject is a factor in this (yes I realize you have IS in the lens) in addition to some of the other factors noted above. That's why I think a tripod is, next to one's camera, the best tool in the field.

Even some of the better sample shot posted are not 100% sharp. This may be due to atmosphere as well as camera movement.[/QUOTE]

The old rule does not have any effect on subject movement.

If for example Roy's image is unprocessed and compressed then I think it is sharp enough.


I do agree that sometimes too much may be expected under certain conditions.

 

[swamp_rattler]

If nobody minds an off-topic question...

How do you guys get those shots where it shows your focal points and, in red, which one was activated? Unless you're just photoshopping that in?

Sorry!

 

[eastwood]

If nobody minds an off-topic question...

How do you guys get those shots where it shows your focal points and, in red, which one was activated? Unless you're just photoshopping that in?

Sorry!

If you are using Canon, view your image with EX zoom browser, click onto "view" and there is a line "show autofocus points", click onto it and it will show you.
Or if you view it with Canon's DDP, click the image to full size, then click on view, then on the AF Point, (the clicks are always left clicks.)

 

[Steve Babbs]

If nobody minds an off-topic question...

How do you guys get those shots where it shows your focal points and, in red, which one was activated? Unless you're just photoshopping that in?

Sorry!

Zoombrowser - which comes with Canon products - can show them. I presume some other software can as well.

 

[Brian Bullough]

I think my software must need updating /calibrating ,when I look at focus point on the photo it is often (very ) not even on the bird or it could be the camera !!
Brian

 

[davethebird]

If nobody minds an off-topic question...

How do you guys get those shots where it shows your focal points and, in red, which one was activated? Unless you're just photoshopping that in?

Sorry!

Use the Canon DPP to open the image and select the option to display focus point.

To copy the screen image I use a piece of freeware called Gadwin Printscreen. This then transforms the PrtScr button so that when there is an image displayed on your screen, press PrtScr, select the area you want to copy, then save it as a JPG or print it. If you can see it on your screen you can save it as an image. :t:

 

[h14nha]

It looks like the camera missed focus and picked out the wing/sky as its contrast point. If you zoom into the wing is the picture IQ any better ??

 

[mr_birdman]

Aside from other aspects such as AF performance, tracking speed etc I think the most important part of taking a bird photo is to get them as big in the frame as possible. The further you are, the more air between you and the subject, the less area it occupies in the frame and you will have not enough detail to process. I generally strive to try to get the birds to fill at least 75% of the full frame image, regardless of sensor size. I've never managed to get an awesome, detailed result with the birds filling a very small part of the frame.

 

[tdodd]

I've never managed to get an awesome, detailed result with the birds filling a very small part of the frame.

As a result of this thread I did try practicing a little on distant birds, both in flight and settled. With BIF, shooting in short bursts I did notice variations in quality from frame to frame, with some being almost usable at 100% and others bearing some similarity to the OP's example, although not so severe.

The first example below (Attachment 1) shows two consecutive frames fired with my 1D3 in a burst, with one being pretty decent and the next being very ropey. You might notice that the first shot had a little fill flash thrown into the mix, resulting in a 1/300 shutter speed, whereas the subsequent shot has no flash and is at 1/320. I don't see that the use of flash makes a scrap of difference to the sharpness, but I point it out just in case anyone thinks it might. It seems clear from the change to the framing that I had some vertical camera shake, and just a slight error in horizontal tracking too, and this has affected the second shot severely. If I had only fired one shot rather than a burst I might well have had the second outcome and been scratching my head searching for an equipment fault, where actually the fault would be mine.

I also tried a less demanding target with my 7D in better light, still at a distance, and while it's no prizewinner I think it would just about escape the recycle bin. Attachment 2 is the whole frame. Attachment 3 is a 100% crop with a helping hand from Lightroom. I don't doubt that using a prime lens and a tripod would have yielded better results, but I had to make do with my hand held 100-400. As I was already at the water's edge I had no plans to try to move closer.

I can certainly understand that trying to wave 700mm of glass at a distant bird, with the ISO bumped up and cropping to 100% from a 7D is going to expose a few warts, and while I wouldn't advocate "spray and pray" as a technique for every occasion, it might have been the solution this time.

 

[shepster]

Following all the interesting points made, and trying to isolate each variable in turn as far as is possible, it seems to me that the biggest improvement has come from changing the CFn III-2 setting from 3 to 0. With raptors I realised that I wasn't keeping my finger on the buzzer but was taking individual shots as the bird banked etc. Trouble with that is, with that setting, the focus accuracy of the first frame is sacrificed for speed. But if you're only taking that first frame, and then another first frame a few seconds later....
Anyway, I attach a shot from last week which is representative of the increase in focus accuracy.
Thanks to everyone.

 

[GYRob]

Following all the interesting points made, and trying to isolate each variable in turn as far as is possible, it seems to me that the biggest improvement has come from changing the CFn III-2 setting from 3 to 0. With raptors I realised that I wasn't keeping my finger on the buzzer but was taking individual shots as the bird banked etc. Trouble with that is, with that setting, the focus accuracy of the first frame is sacrificed for speed. But if you're only taking that first frame, and then another first frame a few seconds later....
Anyway, I attach a shot from last week which is representative of the increase in focus accuracy.
Thanks to everyone.

This shot just shows how we can be left wondering -clearly the focus point is no were near the first bird yet it is in focus ,i doult that the plane of focus is the same as the back birds tail were the focus point is closest too .

The point im making is regardless of were the focus point is as long as its close we still need a bit of luck too.
Rob.