Critique Why is this image not sharpe

BillN_33

BillN_33

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Taken at 1/2500th sec at f5.6 with a 600mm Nikon lens and a D7100 on a really good tripod with a Wimberley gimbal

Presumably the 1/2500th sec should eliminate "motion blur" … but does that speed reduce any blur that is caused by "bad technique" in "holding" such a long lens …….. or can you suggest any other "problem" (photographic, please), that I may have

or did I just miss the focus?

it's a crop and obviously taken from a distance

sharpe.jpg
 
Is this cropped or is this a smaller version of the full size image?
 
The water looks ok just behind it so i'll go for missed focus.
 
I'm inclined to agree with Andrew on this one.

It certainly looks like you've focussed on the water slightly behind the bird.
 
Depth of field would possibly be too shallow. f/5.6 on that lens at 50 feet is only about six inches, so as said above the slightest movement on a 600mm lens means you could miss focus
 
Thanks , he is another 2 that I am disappointed with as I feel I should have done better ……. as the bird was swimming away from me so not much "bird" movement

1/320th sec at f5.6

sharpe_2.jpg




1/400th at f5.6 ……… but happier with this

sharpe_4.jpg
 
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BillN_33 said:
Taken at 1/2500th sec at f5.6 with a 600mm Nikon lens and a D7100 on a really good tripod with a Wimberley gimbal

Presumably the 1/2500th sec should eliminate "motion blur" … but does that speed reduce any blur that is caused by "bad technique" in "holding" such a long lens …….. or can you suggest any other "problem" (photographic, please), that I may have

or did I just miss the focus?

it's a crop and obviously taken from a distance

sharpe.jpg
Click to expand...

Glad you posted this Bill, it is something I suffer with and concluded for mine too far away even though it appears in the viewfinder to be focussing on the eye, secondly big crops do not do any favours in my experience, the water does look focussed just behind the bird but then again I think around each focus point is a bit of tolerance if that makes sense
 
BillN_33 said:
on a really good tripod with a Wimberley gimbal
Click to expand...

Although that is obviously a great help, unless you have it locked down (unlikely with moving wildlife) you are still going to risk 'involuntary' movement as you pan/tilt/click :)
 
Thanks everyone …………. I think that i expect too much from the equipment, (at a distance), and need to work on my technique with the lens …… it was my first time out with the 600mm today and i was a little disappointed versus my 300mm f2.8
 
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That is a massive magnification. 12 x 1.5 = x18 ; about twice as much as a pair of binoculars! Plus the crop on top of that.

Potential subject movement and/or camera shake as well on the bottom two due to relatively long shutter speed?

Maybe you're just asking too much of your equipment and your technique?

Possibly still shaking with anger after starting another discussion on "art"? ;)
 
Thanks Jeremy

just waiting for the "Brothers Grim" to chime in ……….. they will try to resist …….. but the temptation may be too much ….?
 
Given those settings and the crop it looks fine to me Bill.

sharpe_zps5adff3ee.jpg
 
I would say you have slightly missed focus. Try it on carious static subjects at different lengths to see if you need aome micro adjustment added.you have only just got the lens and they do take some getting used to to get the most from them. I had the same for a few weeks but now i often shoot from a tripod and gimbal at 1/20th or 1/30th for stTic type birds and im happy with the big lens performance.
 
I enjoy looking and learning because this is very new to me but there is one bit of information missing, the camera and lens settings are there and the way the camera is mounted but what about how the shutter is released?
 
Littletank said:
I enjoy looking and learning because this is very new to me but there is one bit of information missing, the camera and lens settings are there and the way the camera is mounted but what about how the shutter is released?
Click to expand...

I squeezed the shutter slowly and rested my left hand gently on the middle of the lens at the point where it is balanced on the Gimbal, then bearing down pressure and (weight) to try to eliminate any vibration in or along the lens caused by the mirror movement…….. I had my rucksack, (containing my sandwiches, a small bottle of water and an apple), hanging from the centre column to add gravitas, as a pro would

The tripod was a very good Gitzo carbon with a Wimberley WH200 gimbal … been going mad spending money in my retirement

…….. I was in a hide with a wooden floor and standing behind the tripod, (i.e. not sitting)

There was one other "old" guy in the hide sitting quietly eating his wine gums

The light was typical, strong winter sun from rightish to left ………throwing shadows ………….. the camera settings were single cell spot focus and spot exposure, with the single focus point on the eye.

You will find that if you operate in Live view and lock the gimbal down ….. there is still movement in a long lens …… that's why for beginners, (like me), it is important to use a high shutter speed even in that means a higher ISO than I would care to use.

I think that there are the following problems:

1). First day out with a (new) lens ……. it is long, heavy and I need to get used to it and improve my technique.
2). Subject too far away ….. I am expecting too much from the lens at that distance.
3). Light was good but not good.
4). f5.6 is a shallow DOF, the farer away you are the shallower it becomes.

But the main reason is that I'm a bi_focal wearing old git with a bus pass and I'm not as sharpe as I was. I can do something about 1). to 4), but not about my basic problem
 
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BillN_33 said:
But the main reason is that I'm a bi_focal wearing old git with a bus pass and I'm not are sharpe as I was. I can do something about 1). to 4), but not about my basic problem
Click to expand...

Post made me smile Bill, you are out there enjoying your retirement which is the main thing (y) a excellent photo published on front of mag is just a bonus :D
 
I don't think it's a big issue here, but don't forget about atmospheric effects. The greater the distance between you and the subject, the more likely you are to encounter issues with heat haze.
 
The W said:
I don't think it's a big issue here, but don't forget about atmospheric effects. The greater the distance between you and the subject, the more likely you are to encounter issues with heat haze.
Click to expand...

Heat haze at this time of year, would that be possible?
 
Are you using single point focus (on the birds head) and focusing mode set to tracking ie subject is moving
 
Swanseajack said:
Heat haze at this time of year, would that be possible?
Click to expand...
Well, heat haze is about a change in temperature than absolutes, so it's possible any time. If the ground or water is hotter than the air temperature, you'll get convection heat transfer and the density changes we call heat haze.
 
The W said:
Well, heat haze is about a change in temperature than absolutes, so it's possible any time. If the ground or water is hotter than the air temperature, you'll get convection heat transfer and the density changes we call heat haze.
Click to expand...

I understand that, but at this time of year. Would there be a big difference in temperture between the water and air to cause haze. I could understand if there is bright sunshine hitting cold water. Looking at the original photo it seems to be in good light and probably not to early in the morning.
 
Thank you, Bill, for your detailed answer but, with all the various possibilities for camera shake, is it not possible to use a cable release?
 
Littletank said:
Thank you, Bill, for your detailed answer but, with all the various possibilities for camera shake, is it not possible to use a cable release?
Click to expand...

Thanks Norman

my answer was a "bit" of fun

I suppose that I could also use Mu, (mirror up) ……. and be quick …… which I tend to if say I am taking a close up still shot and similar

I have also noticed with a few 600mm shots .. even on here, that if you are not careful you think that you have focused on the eye and the focus point can move very slightly if, as gramps said, it is not "locked down" when you press the trigger.

I think that my technique is the problem and (I hope), that I just need more practice.

Thanks for your comments
 
Setting the AF-ON button (on a Canon, I don't know the Nikon equivalent) so that your thumb exclusively controls the autofocus and your finger controls the shutter, may help. But sometimes better than that, lock it down and use LiveView (with enlarged view of the focus point) and a cable release, will reduce camera movement.

And while using LiveView you can fine-tune the focus manually while viewing a greatly enlarged part, such as the eye of a bird.
 
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Someone has already suggested the camera might be backfocussing. I have a Nikon 300mm F2.8 VR, a high quality lens but this one front focusses slightly. A +4 correction in the AF fine tune setting turned around a rather mediocre performance when wide open into a top flight one. It's excellent with a 1.4x TC and pretty damn good with a 2x too, but only after careful AF fine tune with each TC. I used a burglar alarm on a wall about 100 yards away as a fixed target but any clear fixed target will be fine. Even better if there is stuff before and behind your target as you can see which way you need to adjust to, but the target must be reasonably large in the viewfinder to make sure your AF can get it accurately. If shooting jpegs, turn off sharpening and noise reduction, better still shoot raw. Set iso to 100, single shot, centre point AF and use a firmly fixed tripod on a solid floor. Use a remote release with mirror-up. Set your lens to aperture priority and maximum aperture, and shoot three shots in turn at each AF correction, starting at 0 then adjusting in single steps to say -4 (-ve values to correct for backfocussing).
Check the results on your PC and adjust as necessary. If you use teleconverters you'll need to do this again with each TC fitted. Your camera can remember the separate settings for each lens/TC combo.
 
smudgie49 said:
Bill are you sure about point 4 above?
Click to expand...

I think so …….. or maybe not?

because you tend to focus on the eye and see the whole body which is OOF at a distance ……. more so then when the bird is nearer?
 
F5.6 isn't especially shallow....and the DOF increases as you increase the distance between camera and subject. With your 600mm lens and camera at f5.6 the corresponding DOF at 10m between camera and subject would be 6cm, at 20m it would be 24cm and at 30m it would be 55cm. Hope this helps.
 
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