Ugh ...Lens issues...Advice please?

Mischief

Mischief

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Jason
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Bought a Sigma 70-300 APO DG a little while ago,and while reasonably happy with it at first,i was convinced that the lens needed much better light than i was shooting in.
However...Now the weather has improved a bit-i decided to take a couple of test shots in bright sunshine,Tripod mounted with 10 sec self timer to eliminate any camera shake etc.
and the results are...Ugh ...Not good..
Just seems that the len's focus is off a little..(Camera body is OK as my Canon lenses work fine.)
Below are two 100% crops taken today,with links to full size images for comparison.
Dont need any crit on the photos-they just snaps to see lens performance.. ;)
Dunno if its just me being "picky",as i know the 70-300 softens a little at the long end...but..This just seems a bit too much :(
(lost the receipt too!)

100% Crops:-
Image2.jpg

Image3.jpg


Links to full size:-
http://www.jasephotography.net/IMG_1454.JPG
http://www.jasephotography.net/IMG_1455.JPG

Anything i can do to sort this? ...Or is the lens a "Bit Dodgy"
Just cant get sharp images from it-Even when dropping down to the 100mm ish range.. :/
Thanks all :)
 
What was your shutter speed and aperture?

Are you sure your camera was rock steady?
 
Considering the apertures you've used and the fact that you were using a tripod, those shots do look a little fuzzy. Incidentally, simply using the self timer won't necessarily remove all chances of camera shake unless you also enable mirror lock up.

I have to say, with the second shot especially (nettles), it does look as though there may be some camera movement to me.
 
The steeple shot was 1/500 @ f8/ 300mm.
the nettles 1/395 @ f7 300mm

Was hoping the lens would be OK for hand held work,but cant even get decent results on the pod. :/
As for mirror lockup.. umm
Anyone tell me how to enable that on a Canon please?
Will give it a shot and see how the results turn out.
(although i think if i need to go to such lengths to get half decent results then i need a significantly better lens!.. Love walks snapping UK wildlife)
 
Ultimately this is a reasonably cheap lens and I think you're probably expecting a bit much tbh..

Doubt it'll make much difference with those shutter speeds, but by all means try mirror lockup - not familar with the 1000D but I think this facility is usually in the custom functions menu.

One last thing - if for any reason you have a filter on the lens remove it before testing..
 
What tripod are you mounting your camera on? Cheap ones tend not to be as stable as you might think....
 
Mischief said:
The steeple shot was 1/500 @ f8/ 300mm.
the nettles 1/395 @ f7 300mm

Was hoping the lens would be OK for hand held work,but cant even get decent results on the pod. :/
As for mirror lockup.. umm
Anyone tell me how to enable that on a Canon please?
Will give it a shot and see how the results turn out.
(although i think if i need to go to such lengths to get half decent results then i need a significantly better lens!.. Love walks snapping UK wildlife)
Click to expand...

There is an other user of that lens posting on this forum looking to upgrade.
http://www.talkphotography.co.uk/forums/showthread.php?t=121518

Ask him if his results were like yours.
 
Yeah that looks about right for that lens. Sorry mate!

Mirror lock up is enabled through custom functions.

Have a look at the Canon 55-250IS

Pin sharp, and can be had (if you're lucky) for around £150.
Superb lens.
 
I had this lens ,to be honest ,that shots are about as good as you'll get at 300mm am afraid
 
Thanks all for your replies.
I did try removing the UV filter from the lens,but it made very little difference.
Have decided to stick it on ebay,and have a look for the Canon 55-250 IS as suggested here.
Have seen some great results from others with a siggy though-Guess they either got lucky with theirs,or are real good in photoshop :D
(If only could afford an L series atm... *Sigh*)
One day! ;)
 
Oh dear , I'm on the verge of buying a Sigma 70-300mm Apo DG. from all I've read it's about the best 300mm zoom that I can buy new within my budget though so guess I'll just have to bite the bullet and hope for the best.
 
I had one of these lenses and i have to say mine was a lot sharper than that on my 50d.
 
What focus were you using? On my (Canon) 70-300 I usually use AI Focus.
Was using that at the weekend on my 28-135, results were as you had here. When I changed to 1-shot, things crisped up (I think, this was via the LCD).

Not that it should make any difference, but I was taking still objects, as are you.
 
It may just be that mine is a little "off" with my body..
If i could find the receipt i might even have been persuaded to try a replacement. (Is a bit late now though i guess)
Really hope you have better luck than i did,was really excited when bought it-the reach is great!
But ultimately useless with the kind of clarity i was getting. (And in great lighting conditions,tripod etc...you should see the handheld wildlife/birding results in moderate light....Eeeew!-Woulda been better off with a £5 disposable camera :D)
The "much sharper" on 50D does at least show that not all of them are that bad...

Tried various focussing methods btw-Manual...AI Servo..Single Shot...Just cant get good results...
 
stu_the_flat said:
I'm really happy with mine (Nikon fit). I'll try and upload some photos that I did hand held if you want?

Stuart
Click to expand...

Sure-Would be great to see some decent images.
Might lesson the desire to introduce mine to a 2lb club hammer :)
To get any kind of "useable" result i have to sharpen the images to death-to the point they just look daft...
Not really what i was after ;)
 
Right So I am new to photography so if these images are unbearably armature please forgive me! They are not amazing crisp but for every day use quite acceptable.

these two are at 300mm

The pound and the ring was taken on a £20 tripod indoors with light form a desk lamp I used the 10s timer like you. I am beginning to think that the plastic legs can oscillate.

http://i410.photobucket.com/albums/pp189/stu_the_flat/LannyPretty070.jpg
http://i410.photobucket.com/albums/pp189/stu_the_flat/LannyPretty070crop.jpg

this was hand held. I have to manual focus I find that supporting the lens by the plastic part furthest from the camera works wonders.

http://i410.photobucket.com/albums/pp189/stu_the_flat/LannyPretty269.jpg
http://i410.photobucket.com/albums/pp189/stu_the_flat/LannyPretty269Corp.jpg

I can upload more photos but they are of my parents rather scruffy farm cat!

Hope that helps Stuart

EDIT: Sorry I have just relised that Photobucket has resized these images. I will re-upload.
EDIT: FIXED! :D
 
Mischief, the first image looks like camera shake to me, although I don't see any clear evidence to demonstrate that - it's more just an impression. However, on the second image the evidence of shake is very clear if you zoom in on a different part of the scene. At 1/400 I doubt a breeze was the cause of leaf movement but just look at the edges on the leaves here....

20090322_113023_1455_LR.jpg


Before you write off the lens I think you need to take a closer look at your tripod, head and connection to the camera. MLU would be a good idea, to reduce vibration, as would a nice weight pulling down firmly on the tripod.

Since the camera has a Live View feature you could check the accuracy of focus by zomming in to Live View at 10X magnification. Then try a shot with the self timer while in Live View mode.
 
That really made me think...
However..One thing bothers me with the camera shake/movement thing..
If the camera moved-wouldnt every single part of the image show the same effect?
While some parts of it do appear as though shake was responsible..Other parts do not have that "double edge" look.
even many of the "hairs" on the nettle stems show only a little OOF effect-not the movement kind... (Or am i missing something obvious here?)
i will try some more shots-and put the cam on a rock solid base..See how i get on.
But even so-Should such lengths really be neccersary?-In bright sunlight at (reasonably)high shutter speeds?
(Sorry if i sound a tad dumb on this subject! :) )
And i do appreciate the help everyone is giving :)
 
You're right to question my observation. I did wonder about that myself, but clearly something is moving. You really need to eliminate as many variables as you can. That means shooting something that does not move, unlike leaves, and taking as many steps as you can to eliminate camera shake. You may have a problem with AF accuracy. You may have a problem with a soft lens. You may have a problem with your camera, or your tripod, or something else. At the moment there is room for doubt about too many things to be certain where the problem does lie. Using Live View should allow you to eliminate or confirm AF misfocus as one problem, or indeed a soft lens. If you can eliminate those then you can move on to things like shutter speed and camera shake.

There are other factors when it comes to simple sharpness/softness - do you shoot raw or JPEG? What are your sharpening parameters or sharpening workflow. There really are a lot of variables to pin down.

EDIT : Another thought about the spire/roof - how far away was it and how warm was it? When shooting subjects at a distance you can get atmospheric effects, like heat haze, or pollution that can muck things up. At shorter distance there is less air to get in the way, but at longer distances.... If you want to try to tighten up on your testing you might want to pick a target a bit closer, like maybe 5m away or so. Just one more variable to be pinned down :)
 
Thanks for that tdodd :)
Tommorow i will set up a 100% static object at set distance,and attempt to nail the damn cam in place. :)
Hopefully will have good light,and perhaps like you say-can start to narrow down the variables a bit.
(I have nothing against the lens/Sigma etc-And if i can show the lens is defective,then perhaps i can get it replaced...I belileve that even without a receipt,the onus is on the shop to dig out the purchase info?-they did take my details etc so should be able to dig up the sale..)
of course-The lens could be fine and its just me! :)
the spire as a guesstimate would be around 200ft away.
Will have a look through custom funcs and enable MLU,with the camera as solid as i can get it,then post the results.
Would have done more today,but ended up in A&E with suspected heart attack... Turned out to be Plurosy.. Fun! :)
Thanks again for your help-Much appreciated!
 
Another point to note.... I know these shots were on a tripod, but something to bear in mind when handholding a 300mm lens - Back in the 35mm film days there was a rule of thumb for minimum shutter speed to avoid camera shake when handholding a lens. The rule (guideline) was that shutter speed should be at least....

_____1_____
Focal Length

e.g. with a 300mm lens your shutter speed should be at least 1/300.

With today's crop cameras the rule is modified to be at least....

__________1____________
Focal Length x Crop Factor

The crop factor for your camera is 1.6, so your minimum shutter speed for handholding should be 1/(300x1.6) = 1/480. The nearest faster shutter speed available is 1/500. Some people can shoot at slower speeds than recommended, while others with shakey hands need even faster speeds. If your tripod is not doing its job well then camera shake could still be an issue, in windy conditions, or if it is generally less than rigid.

Another point about the old 1/(focal length) rule (guideline) is that the amount of shake that was acceptable was only so at "normal" print sizes - perhaps up to 10"x8" or so. With digital, if you view your images at 100% that is equivalent to enlarging the whole image to something like 36"x24" or perhaps even more. That's an enlargement almost 4X greater than the rule was intended to satisfy. Such high degrees of enlargement mean that camera shake is magnified, and something that would have looked fine in a 10x8 or 7x5 print suddenly looks awful when viewed at 100%. With that level of pixel peeipng your 1/500 guideline speed should actually be more like 1/2000 (4X faster).

Pixel peeping can be a dangerous game, leading to disappointment with no good reason. The real question to be satisfied is - do your pictures look good at normal viewing sizes?

If we take your full images as posted and resize them to a more "normal" viewing size, is there a visible problem? Let's have a look. On my screen these are the size of 6"x4" prints. On other monitors they may look larger than that...

20090322_112954_1454_LR.jpg


20090322_113023_1455_LR.jpg


Maybe there is a little room for improvement, and we know for a fact that in the picture of leaves something was moving quite a bit, but viewed at "normal" size they aren't awful by any means. At the end of the day you are using a £155 consumer zoom lens. Don't expect the performance of a 300mm prime or a zoom lens costing several times as much.

Back to the tripod, are you using it with the centre column extended at all? If so, lower it back down for best results. The centre column should be raised only as a measure of last resort, and then only as little as possible. If you need to routinely raise the centre column then your tripod is too short. Here are my two tripods. The tape measure is set to the height of my eyeline. As you will note, even with the centre column fully extended my old, crappy, cheap tripod can't place the viewfinder at my level. It's a recipe for backache and wobbly photos. The thing is all but useless. On the larger tripod I can use that quite well without extending the centre column at all, or only a couple of inches at most. They are worlds apart in design, construction, useability, performance and price.

Column down :
20090324_092842_0339_LR.jpg



Column up :
20090324_093057_0340_LR.jpg


There are a couple of articles on tripods....

http://www.callofthewildphoto.com/articles/camera-tripod.html
http://www.bythom.com/support.htm
 
Interesting point.
Just had a little play in PS,and after resizing to fit a 10x8 print,the problem is far less apparent.
(10x8 being pretty much what i use most)

To really wind me up,the wife tried the lens out,handheld at 300mm/AV mode,and the results are far better...
swan1.jpg


Shot in JPG,with just a single Unsharp Mask applied.
I think perhaps you hit the nail on the head..
This lens just wont stretch to 100% crops with good detail-And i really shouldnt expect it to at the price either.
For the amount of cash id get-i think il probably keep the lens regardless,and simply take a long hard look at just how im using it.
(I had been comparing the results with full size 18" and 30" prints taken using one of the Canons for portraiture...But perhaps the comparison is somewhat unfair.)
Time to start saving the pennies for better glass if i want reach and high IQ i guess! :)
Thank you very much for opening my eyes a little,and showing me things arent always as bad as they seem!

*edit:-Your "Crappy old tripod" looks surprisingly like mine...lol-I kinda walked out with 50 quid in my pocket and picked up the first tripod i found... BIG mistake!
Really should know better..ie-when buying PC components i wont settle for less than the best,and expect to pay for it...Why on earth i bought such a crap pod il never know..
thx again :)
 
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