Is this sharp ??

mrgubby

mrgubby

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Brian
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I'been playing with my new lens (Sigma 70-200) for a couple of weeks now & can't make my mind up as to how sharp it is.

This is a 100% crop from a Robin, straight from RAW with no processing . Is it as sharp as it should / could be or are my expectations a bit high :shrug:

EXIF:- 1/320 , f10, 200mm, ISO 200

sharp.jpg
 
My experience with Sigma lenses show similar results, especially with my 10-20.
 
Well its not sharp, but its difficult to handhold @ 200mm and 1/320th, if you can imagine holding a I dunno, 10ft.. stick from the same position to the bird, any movement is magnified.
You can make it easier, give yourself a better chance of eliminating hand movement by shooting a faster shutter.
At 200mm, you dont need f/10, dunno that lens but f/2.8 will get you good dof on the bird and isolate it by blurring the background
Theres a formula that escapes me for handheld shutter times - focal length
As far as I hear, sigmas 80-200 f/2.8 is.....sharp
 
I'd say it could be sharper but it does not seem like a fair test. Pin some newspaper to a wall and take shots square on at different apertures from a tripod then you might have a better idea.
 
I think you'd be better testing the lens on a perfectly static object.

Even though you might think you've avoided shake with the 1/320 shutter......how do you know the breeze wasn't moving the branches? :)

I can manage to get shaky images at 200mm hand held with faster shutter speeds :eek:
 
:agree: ... in the case of your Robin it may well be you rather than the lens causing the un-sharpness ... :shrug:





:p
 
ah..

The generic rule of thumb is that you can expect to successfully hand hold your camera down to a shutter speed of one over the focal length. For example, if you are shooting with a 200mm lens, hand held shots should generally be sharp if your shutter speed is at least 1/200 second.

ah...but...thats for 35mm, so theres a multipying factor of.....ugh...more formulas....1.6....god I dunno

1/320th seems a little close to the edge if your not taking diazapam
 
I tend to wander round with the camera set to 1/320 in tv mode , it wasn't until I got back that I noticed that I was getting f10 apertures & could have gone a lot faster :bang:
 
mrgubby said:
I tend to wander round with the camera set to 1/320 in tv mode , it wasn't until I got back that I noticed that I was getting f10 apertures & could have gone a lot faster :bang:
Click to expand...

I dont know how you can concentrate while watching tv..
Set 2.8 in ap priority and the shutter will always be as fast as is possible under the conditions.
Saying that tho, Sprogs looks a bit soft at 2.8, f8 is sharpest on his target...
 
I think it's time to get the tripod out, I've got some targets under the sink :thumbs:
 
The results were pretty much what I expected, most lenses get a bit woolly wide open, it's a price we have to pay if we want the speed.
 
Then there is the fact that you have not processed the shot at all. If this is raw then I think it is acceptably sharp. Most cameras sharpen to a greater or lesser degree in camera, but please someone correct me if I have my facts wrong, I always expect to apply a little sharpening once I have done any processing.

I think for a hand held shot at 100% raw that is a remarkable shot. Does someone else have a Nikon or Canon equiv lens they could post an image from to compare?
 
I could understand if it was at 200mm and wide open at f/2.8 but at f/10 that does seem a little soft mate.
Ive quickly tried to emulate a similar test to try and give you some thing to gauge it against.
I haven't got the Sigma but this was taken with my Nikkor 80-200 f/2.8.
Theres no birds handy at the moment, but heres a shot of "monkey" :) sat on my cooker,taken at 200mm and f/10 and a 100 % crop straight out of the camera and just resized.Shot in RAW and converted.Not very scientific I'm afraid.

NKN_7103.jpg


NKN_7103crop.jpg
 
does look like it could be better, as other have said. I'd expect to be able to count the fronds on the feather (or stitches in the PG t-shirt). I can with my 70-200.
But as the others have said you need a level playing field - try what RP suggests with a tripod and see how that compares
 
Bob , the EXIF says that it was shot at 1/60 so I guess it was on a tripod / resting somewhere ?

OT , why is there a line drawn round the monkey or is it just a reflection ?
 
mrgubby said:
OT , why is there a line drawn round the monkey or is it just a reflection ?
Click to expand...

Forensics. 2seconds after this thats all that was left.. and a smouldering t-shirt. :)
 
Hi mate, yeah on a tripod , just popped up the on camera flash and shot at 1/60th.
The line is "monkeys" reflection against the shiny plastic bin hes leaning against.
 
Just eliminating the obvious possible mistakes...

I take it you had only one AF point enabled?

Were you shooting in Servo AF?

We really need to see a shot showing the point of focus.

That's a pretty fast shutter speed, even for hand held with that lens. I'd suspect a focusing technique issue rather than a problem with the lens...certainly something to eliminate before looking further.
 
I agree with CT.
You probably need to set up something more controlled to assess it.
 
mrgubby said:
I'been playing with my new lens (Sigma 70-200) for a couple of weeks now & can't make my mind up as to how sharp it is.

This is a 100% crop from a Robin, straight from RAW with no processing . Is it as sharp as it should / could be or are my expectations a bit high :shrug:

EXIF:- 1/320 , f10, 200mm, ISO 200
Click to expand...

I think it's probably ok.
The clue is in you saying it's a 100% crop of a raw image.
I have never had a camera yet that produced raw picture that needed no sharpening or contrast adjustment.
If you don't mind? I'll have a play with the crop you supplied and see if it's just a lack of post processing!
 
CT said:
Just eliminating the obvious possible mistakes...

I take it you had only one AF point enabled?

Were you shooting in Servo AF?
Click to expand...

Single point AF , one shot focus

soupdragon said:
I think it's probably ok.
The clue is in you saying it's a 100% crop of a raw image.
I have never had a camera yet that produced raw picture that needed no sharpening or contrast adjustment.
If you don't mind? I'll have a play with the crop you supplied and see if it's just a lack of post processing!
Click to expand...

That's one of the things I was checking, I think that the monkey shot ;) shows it could be sharper.

If I get a chance today I'll do some tests shots in a more controlled enviroment and post the results :clap:
 
Well, given I don't have the raw data, this is the best I could do.
It looks a fair bit crisper to me but, I am sat at work and don't really have the software I want.

sharper.jpg
 
Had a quick investigation, found out a few things.....

1. I wobble more than I expected. I must use higher shutter speed when I'm Birding :bonk:

2. At f2.8 I seem to get a slight yellow tinge to shots ?

3. At f2.8 / 2M from target , tripod flex is greater than DOF :nono:

4. My Tripod is PANTS, £600 lens on a £20 tripod is a waste of money :lol: (Tripod was bought for a Video Camera :thumbsdown:)
 
mrgubby said:
That's one of the things I was checking, I think that the monkey shot ;) shows it could be sharper.
Click to expand...

The monkey shot hasn't been sharpened.What would I achieve by sharpening it? :shrug:

SIGH...
 
i was in Cameraworld in Chelmsford yesterday and they were telling me that they've been sending lens's back to Sigma as they are too soft. Sigma replied stating that they are within specifications. it looks like Cameraworld is thinking about pulling the plug on Sigma as so many lenses are going back.
 
mrgubby said:
I meant thet YOUR monkey shot showed me that my shot could have been sharper
:wave:
Click to expand...
Sorry mate, I misunderstood your post and opened my gob as usual.
(big foot enters big mouth) I'll get me coat.. :coat:
 
mrgubby said:
I tend to wander round with the camera set to 1/320 in tv mode , it wasn't until I got back that I noticed that I was getting f10 apertures & could have gone a lot faster :bang:
Click to expand...

I rarely use shutter priority mode- apperture priority gives you a better idea of what you're going to get, and makes you think about the shot a bit more (plus my manual focus lenses will only work in apperture priority!!)
 
BigBaldBob said:
The monkey shot hasn't been sharpened.What would I achieve by sharpening it? :shrug:

SIGH...
Click to expand...

Every digital image needs some sharpening it is the nature of the beast, granted some lenses are sharper than others and can get away with minimal or no sharpening dependant on subject but as a rule all digital shots need to be sharpened to get the most from them
 
ppp said:
Every digital image needs some sharpening it is the nature of the beast, granted some lenses are sharper than others and can get away with minimal or no sharpening dependant on subject but as a rule all digital shots need to be sharpened to get the most from them
Click to expand...

Yeah I know mate but we were comparing unsharpened un processed RAW files to see if mrgrubby had a problem with his lens.
 
I had softness issues with my Sigma 24-70mm F/2.8 DG EX macro, I wasn't really happy with it & rang Warehouse express.
They just said send it back, which I did & received a new one two days later. And nice and sharp!:thumbs:

I would say if you're not happy send it back.

Spence
 
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