Same Problem as Tel? (poor focus) C&C please

Or is it as I suspect that common problem operator error.

Acquired this lens in January it is a Sigma 50 -500mm and these are taken at 500mm in poor light with me trying to juggle the aperture to get as fast a shutter speed as possible. I am not worried about the noise but I am concerned that the shots are not sharp. Your comments and help appreciated particularly if you think I should be returning this lens, I have a chance of improving my technique but the lens, if faulty will not.
[IMG]http://img.photobucket.com/albums/v173/Thordell/Starling_.jpg[/IMG]

[IMG]http://img.photobucket.com/albums/v173/Thordell/LongTailTit.jpg[/IMG]

[IMG]http://img.photobucket.com/albums/v173/Thordell/HouseSparrow.jpg[/IMG]

[IMG]http://img.photobucket.com/albums/v173/Thordell/GoldFinch.jpg[/IMG]

Sorry too big, will have to learn to get that right

what distance are you away from thr birds, are these crops,:

If the light was poor you have the double problem of camera shake and subject movement.

I would try again in good light and see if you are happier then.

Hi Jackie,
I have been testing all day and got no where have decided to send my K20D back to Pentax on Monday, heres a list of whats happened.

1-Miss writing files to card, Reset to factor settings, removed battery and replace.....Writing to files now OK.

2- Started to find focus out on DA.55-300 then over this week focus off on 50mm.f1.4 and today Sigma 400mm of focus as bad as your first shot.

Hopefully they can fix it as it should be, if not it will be more expense to change back to Nikon or might try Olympus carn't be any worse.

By the looks of yours maybe Pentax is your route as well.

Sorry to hear that Tel hope it all works out for ya

Are you using a tripod/monopod?

I know the 50-500mm is a pretty large lens (hopefully getting one in 2 weeks time). It's larger than the 135-400mm I have now and that is a bit heavy for hand held under all but perfect conditions (which you didn't have by any means).

Also they look very heavy crops and I notice from 2 different cameras Wide open?.

Yes, they are crops, will sort out one of the originals straight from the camera, and yes, I was using a tripod but not a remote release, and yes, it is a big bu@@er. Don't think I can blame the K20 because I have sharp shots with different lens so if there is a problem other than the operator then it is the lens I would think.

Jackie,
In case you don't know save shots at 800pixs on the longest side.

Unless you have a really steady tripod you will get movement when you press the shutter release, certainly with the Bigma on it. I assume you had the Bigma on the tripod not the camera?
These were taken with both a Ds and the K20D - the Ds offers less "cropability" than than K20D does which will result in poorer quality images. The noise levels don't help either when cropping.
It would be good to see the uncropped versions.

Edit: if you don't have a remote release, either the IR or a cable one get one. Whilst you can use the 2 sec delay to counteract wobble it isn't any use for birds.

if you got them at a feeder, why not try setting up some lights?
perhaps you can get an aperture/shutter/iso combo that you KNOW should give you sharp images... and also test your lens to see if it is front/back focusing...

if you are using a tripod, the sr should be off, there was a fella here that tested that and found it could lock up the camera and require pulling the battery out to rest the camera...

Jackie,
My input is from a very inexperienced point of view, so please take it with a pinch of salt.

I use my K20 with the 300mm plus the TC on it and I have seen many shots of mine like the ones you have. And I have some which came out pretty sharp, if you see on a couple of threads where I have put up some of them you will see what I mean, just a couple of days ago me and Scott were having a go at birds having a whale of fun time.

My point is this, I often get shots which are like the ones above when light is a huge problem. That is one of the problems, but high iso also ruins them. I also notice that no matter how much I lock on to focus, often even manually you just cant get the sharpness alive on them depending on the angle of the light. And on the other hand when the light is good or from the correct angle the shots are absolutely great.

At first I used to think that its the lens or I might be doing something wrong, but then with time and thanks to the flocking of the birds in the backgarden I have come to these conclusions.

Its very upractical to use remote while shooting birds. More so when I have the TC attached because my left hand is on the focus ring, the right hand alternating between the handle of the tripod to lock on to position, which by itself is hard as they keep moving and then suddenly when I find the spot my right hand goes straight to the shutter for the release. I have thought about using remote but its so fiddly, I do keep it in the pocket (my right pocket) and in fact my K20 is left constantly set up for remote shutter, but if I go fiddling to the pocket and by the time I take it out and release the shutter it might be too late.

So the action of the hand from the tripod handle to the K20 to press the shutter is the closest and in my opinion I think, provided your lens/K20 is mounted on a tripod, there is little chance of shake.

The other reason I remember getting shots like that was the distance from the birds I was taking the shots from, I still have a few like those but they were mostly because I was way too far.

Even today I took this one hardly 20 ft away but look at the result. This was definitely due to the angle of the sun which did not allow me to lock in properly to get the sharpest of the images. I shoot the birds from the same location, just at different times of the day and the angle of the sun makes such a huge difference, sometimes just a few minutes or a branch of the tree allowing the sun through and a great shot comes through.

Look at the two shots, taken from exactly the same spot but the difference is tremendous.
Hope this helps. But I would certainly keep trying.

This one lacks quality, sharpness being the main culprit, but I could swear in the viewfinder I was pinpointed,(I use a magnifier), its just the sun that was totally against me, look at the glare on the right side, on the head, even the feeder reflects so much light due to the angle of the sun,



While this one in my opinion came out better, much better actually

Sorry to stretch this thread everyone, but I just thought I should put up some examples and may be it will help drawing the conclusions.
Apologies as the Great tit was taken without the TC and the goldfinch with the TC, but I just dug out two more examples of lack of sharpness and they were precisely taken seconds apart, same spot but the plumage being different and most probably the shadow underneath the starling also has a huge influence for me as you will notice from the starling the lack of sharpness is latent.
Both taken one minute apart, at exactly the same settings

I think as I suspected the problem is with the operator.

The tripod I used (yes, did have the lens on it) was my Slik and I suspected at the time that it was not up to the job but as I had it rammed between the bath and the wash hand basin where I did not think I would get anything more substantial. Next time I will pinch my husbands Vinten that should manage weight better, it is really a case of if I can lift it, the Vinten that is.

The light was awful but I wanted to try the lens and now I wish I had waited as the results upset me a bit, will try again now the weather is better.

They are heavy crops and I have also had to adjust the original a good deal in processing this is the original of the one I have used in the cropped shot. Looks to me if the point of focus is on the seed in the feeder, could have been the wind I suppose I have one with the birds and feeder almost horizontal, needless to say that is well out of focus as well.

Do think now I have read your opinions that I may have in this lens a bit more than I can handle but I will keep trying now the weather is better and if it proves too much for me and beyond my capabilities I will have to sell it.

Many thanks, helpful as always.


[IMG]http://img.photobucket.com/albums/v173/Thordell/OriginalGoldFinch.jpg[/IMG]

Sorry forgot to ask what is a TC, just know I will feel daft when I am told but at the moment I just can't think.

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