sharpness

Flying giraffe

Flying giraffe

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Neil
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looking for a bit of advice here, ive been out a few times with my 550d plus a 55-250 cannon lens but even setting sharpness high in camera the pictures still look soft, this is obviously increased when i crop the photo in ps, i presumed having 18mp it would still be good, is it me, the lens, or am i expecting too much?
robin.jpg


i have left it as i took untouched, any advice apreciated
 
He looks reasonably sharp given how small he is and the focus is about right - I think maybe you are expecting too much. To take decent pictures of robin sized birds with 250mm you need to be only 2 meters or so away.
 
I agree

You also have quite a slow shutter speed 1/50 for the focal length 250mm.

There is a rule of thumb that suggests your shutter speed should be reciprocal to your focal length. As the image is magnified by zooming in, any camera shake will also be magnified therefore a quicker shutter speed will generally help negate camera shake.

Ideally you will be shooting with a shutter of around 1/250. Now these figures are based on a full frame camera and as you have cropped sensor (x1.6) - you should really calculate it as (shutter speed x 1.6) but as I said, its a rule of thumb. Obviously there is not enough light for that in this shot and your ISO is already at 400. You might only have one or two more stops of ISO to play with before noise is too prevalent.

In saying that, it doesn't look too bad when looking at the foilage. Maybe a touch of brightness, contrast and a little sharpening will bring it out more.
 
It's difficult to tell on my iPad, but by enlarging the image it looks like camera shake to me. Not a lot, but then you don't need much at 250mm.

There's a couple of things you can do though. For walking around the woods trying to get pictures of wildlife, a monopod will help a great deal. £35 will see you with a decent one, and if you already have a tripod, you could also use the same head. As suggested above, you really need to be shooting at 1/400 sec at 250mm, so adjust your ISO if necessary; sometimes a noisy shot is better than no shot at all.

Other than that, you need to get the subject closer to the lens, or increase the focal length, the latter of which is entirely dependant on your budget. I find that focusing on small subjects really difficult, even using the advanced focussing systems on my 7D, and there ain't no replacement for getting the subject much larger in the viewfinder to start with.

Steve

Sent from my iPad using TP Forums
 
thanks for the replys, will take them on board, i do have a gorilla pod so i can take that next time and try a quicker shutter, do you advise setting the sharpness high in the camera, or leave it and do it post?
 
It's also worth remembering that the 55-250mm is a little soft @250mm. Next time try shooting at (say) 240mm as well, and compare the results. Yes you'll be a little further away, but (from experience when I had the 55-250) it'll also be sharper.
 
Have you got the IS turned on, on the lens?
That should rule out camera shake, most of it anyhow

EDIT - Thats presuming it is the 55-250mm IS lens!
 
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it's not your 250mm zooming that is the issue, it is the 1/50th of a second. you should have a minimum of 1/250th so, as has already been said your shutter speed is = the focal distance. That should sharpen things for you.

Also I would be careful about ramping the in camera sharpness up too much as it can lead to some pretty nasty artefacts in your images. I would be tempted to ease it back a touch.
 
here's an old seal shot of mine at 250mm f/5.6 iso 100 1/320
i found the 55-250 a very sharp lens on my 500d/550d
4500386017_b543c9d1e4_z.jpg
 
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Shooting at 1/50 is asking a lot, but the other problem here is the tiny size of your subject in the frame. Cropping is nowhere near as good a solution as getting closer. The more you can fill the frame (without cropping) the better your IQ will be.

Robins are easy targets, usually. With a bit of effort/patience I'm sure you could do much better by getting closer.

This is with a 400mm lens, so obviously a bit longer than yours, but the image was shot without the aid of a hide and is uncropped. That means more pixels on the bird and more light recorded for the bird. No edits at all on this....

20100108_135016_1780_LR.jpg
 
tdodd said:
Shooting at 1/50 is asking a lot, but the other problem here is the tiny size of your subject in the frame. Cropping is nowhere near as good a solution as getting closer. The more you can fill the frame (without cropping) the better your IQ will be.

Robins are easy targets, usually. With a bit of effort/patience I'm sure you could do much better by getting closer.

This is with a 400mm lens, so obviously a bit longer than yours, but the image was shot without the aid of a hide and is uncropped. That means more pixels on the bird and more light recorded for the bird. No edits at all on this....
Click to expand...



Yep nothing kills IQ like cropping into an image. Higher res will help a bit but nothing is going to beat getting your subject to fill the frame more at capture.
 
thanks for all the advice, had another go with my dog this time, cropped as well but think it is alot better, albeit with a sigma 17-70 this time
med.jpg
 
That's much better, but there are many things with that photo to improve matters -more subject, better light (more contrasty), more light altogether, lower ISO, huge step up in shutter speed. These things all make a difference.
 
thanks for the advice tim, i presume you mean with the first photo, going to have another go this weekend and see if i can put all the advice into practice.
 
i had the same problem with this particular lens and it turned out to be faulty but im not saying thats whats wrong with yours
 
I meant the dog photo is much better than the robin because much as changed for the better. Shooting a tiny subject in poor light from too far away is going to challenge anybody to produce good results.
 
thanks Louise, thats something im going to look at, the guy who lent me the sigma 17-70 (which i used for the dog) has a 70-300 that hopfully i can borrow too so i can see what results i get there, im half thinking its because i was too far away, obviously getting closer would scare the bird away, what lens did you go for in the end Louise and how are you finding it?
Tim, you hit the nail on the head, only just getting into dslr and there is so much to think about, but thanks to all the advice im sure ill get there eventually.
 
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