Lens question v Clarity

oblivion

oblivion

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Richard
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I feel silly asking but I'm curious. Just been in my garden to shoot a butterfly on the grass. I had my 55-250mm telephoto attached and standing above the butterfly I just managed to achieve focus having zoomed in to 250mm for a close up. However, with my ISO set to 100 my final image was not as clear as expected. I'm wondering had I used my 18-55mm lens zoomed in to 55mm for the close up would this have been clearer and why? Maybe its just a Tuesday blues thing
 
oblivion said:
I feel silly asking but I'm curious. Just been in my garden to shoot a butterfly on the grass. I had my 55-250mm telephoto attached and standing above the butterfly I just managed to achieve focus having zoomed in to 250mm for a close up. However, with my ISO set to 100 my final image was not as clear as expected. I'm wondering had I used my 18-55mm lens zoomed in to 55mm for the close up would this have been clearer and why? Maybe its just a Tuesday blues thing
Click to expand...

really need to post the shot to get an opinion, Richard.
Maybe out of focus or camera shake.
What shutter speed and aperture did you use ?
 
Also how high above the butterfly where you, You may well have been closer than the minimum focus distance of 3ft 6ins
 
Sorry for the delay, Flickr has made any new photo I recently added as restricted and its taken me best part of an hour to change it. Why change things...so annoying.

Anyhow, photo should be here now. ISO 100, 194mm, f5,6, 1/50 sec. I can only conclude that I may have moved slightly after focus but I'm usually good at being still.

9450120551_d445575d4c.jpg
[/url] IMG_9827 by Pixearl Photography, on Flickr[/IMG]

Same lens - different location, probably 4 metres away from this bird but look at the clarity in the difference, hand held too.

Untitled by Pixearl Photography, on Flickr
 
Also whilst I'm here, most post on here which (include a picture) show on my iphone under the post itself, but whenever I put a picture on here I have to open my post to go to a second page to see the picture? Strange
 
Could be camera shake @ 1/50th I asume you had IS on but your focal lengh is nearly 200mm x that by 1.6 for your crop factor = just over 300mm so you could possibly be at the limit of the IS, I could also be entirely wrong.
 
Think you're right. Only logical solution considering my other pictures
 
Without question, that's camera shake and 1/50 is pushing it at the best of times with anything that's likely to move.

There's an old rule, your minimum shutter speed should be 1 /effective focal length.

So with your lens, at the focal length you were shooting at, the bare minimum would be 1/320.

Obviously, you can practise and use a slower speed but its a good starting point.

Image stabilisation will enable you to work with slows shutter speeds - I have no experience of that lens so I don't know how well it performs.

Remember, you can remove the noise caused by using a higher iso to get the shutter speed you need, you can't unblur your photo once its been taken.
 
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To me the problem is where you've focused, the grass and leaf just in front of the butterfly is pretty sharp.
 
Yes, there's a little bit of camera-shake visible in there, showing its give-away double-edges here and there. You're around the threshold of 'the rule' even with IS, but that guide only applies with a good and steady hand-holding technique and that's hard to achieve when you're bending down and possibly leaning/reaching awkwardly.

Even at the best of times, it only reduces camera-shake to generally acceptable levels, it is never totally eliminated. When near the limit, there's safety in numbers and taking three or four shots in quick successions will often yield one that's usefully sharper than the rest.

The main thing wrong with that shot though is the front-focus. Possibly you focused and then leaned forward a little more without realising.
 
Just a few thoughts not in any order.
It looks like you have missed focus on the butterfly, the grass and the leaf in front are sharp.
Did you use all the focus points or just the middle one?
If you used them all the camera will grab focus on the area of highest contrast, use the centre point.
Shutter speed on the butterfly is too low, so you are quite likely to get motion blur, using the reciprocal guide ( ss=1/fl*crop factor) you should be around 1/400th,alternatively use a bit of fill flash if you want to use a low ISO and SS
 
I used a single centre point only focusing on the head of the butterfly. I think you're right about me moving backwards/forwards slightly taking it out (along with slow shutter). I had left it in aperture mode and wanted the shot quickly so the camera determined shutter speed. Prob should have put it into shutter priority instead.

But using either lens with the same settings set to say 55mm should a picture come out identical or are there subtle differences because they are different lenses?
 
There will be subtle differences but most probably only in distortion - lenses tend to be barrel distortion at the wide end and pin cushion at the tele.

Otherwise, as the lenses are of similar quality the other differences will be small.

edit: oh, and it is possible that the 18-55 will have a higher magnification, i.e. it will focus closer. For some reason kit lenses tend to focus nice and close.
 
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One of the butterfly's antennae is sharp and the other is not. Looks like the lens has been at the absolute limit of it's minimum focus range.
 
Looking at the full sized version I can see the double image as the camera has moved a millimetre or so. Look at the spots on the front of the left wing, fairly sharp dots all with a bit of motion blur in the same direction. The right wing is just out of focus from the narrow depth of field. As you get closer and increase the magnification the DoF will decrease. As well as a faster shutter speed, you may need a smaller aperture (or shoot square on) to get it all in focus but that will mean pushing up the ISO even higher. (Shutter-Aperture-ISO.)
 
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