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tandeejay
20-05-2016, 7:33pm
While on holidays at Maroochydore over the past week, I took a number of photos of Point Cartwright with both my Nikon 55-300mm lens at 300mm, and also with my Sigma 105mm

now that I'm home, I'm finding that all my photos using the 55-300 seem to be rather soft focused, and I was getting better results from the Sigma.

I know that there is a difference between 300mm and 105mm, but I'm just wondering if the softness of the 300mm is a user error that I could correct through practice or changing what I do, or equipment limitation that I'll need to live with.

Here is an example:

Sigma at f/6.3, 1/250 s, ISO200 (105mm)
https://farm8.staticflickr.com/7026/27126758005_0699045223_b.jpg (https://flic.kr/p/Hk6J5e)
DSC_1074_00002 (https://flic.kr/p/Hk6J5e) by John Blackburn (https://www.flickr.com/photos/99216317@N08/), on Flickr

Nikon at f/5.6, 1/1250s, ISO100 (300mm)
https://farm8.staticflickr.com/7363/27031958342_861242a803_b.jpg (https://flic.kr/p/HbHRrh)
DSC_0876_00001 (https://flic.kr/p/HbHRrh) by John Blackburn (https://www.flickr.com/photos/99216317@N08/), on Flickr

arthurking83
21-05-2016, 10:35am
Hi John.
I don't think that it's user error here.
the most probable explanation is equipment limitation.

Reasons: the Sigma 105 has a max aperture of f/2.8, you shot it stopped down to f/6.3
The Nikon zoom's aperture at 300mm is f/5.6, and your settings with the focal length at 300mm was f/5.6(ie. wide open)

Things we generally know about lenses.
While there are exceptions to this norm, lenses usually benefit from at least one or two stops of aperture down from wide open settings.

So, in the case of the Sigma being an f/2.8, then f/4 or f/5.6 would yield about the best balance between sharpness and DOF. f/6.3 is only 1/3 stop down from f/5.6, so in effect the same aperture point.

On the Nikon tho, as the above theory says, if the lens is f/5.6 capable for max aperture, then ideally you'd have wanted f/8 or f/11.
F/8 would have been easily usable given the other settings quoted(ISO100 and 1/1250s), and f/11 should have been easy to shoot with as well with a small bump in ISO.
eg. at f/11, you could easily have shot at 1/640s(1 stop down) and ISO200(1 stop up). Both of those exposure variables would have balanced out the f/5.6 -> f/11 aperture shift.

Now with all the technobabble dealt with, you should be aware that the conditions you are 'testing under' are variable to some degree.
While those variables may or may not have any impact, the problem is you can't really calculate that impact accurately. So it should be considered as part of the overall equation.
In all likelyhood tho, you would expect the Sigma to render a nicer quality image with better contrast and detail .. just based on the variables you've listed .. and disregarding any possible environmental variables.

Something else to be mindful of, is magnification and it's effect.
You should note that the difference between 300mm and 105mm is literally 3x magnification. If there was any likelyhood of vibrations in the camera/lens combo, then at 3x more magnification you'd expect to see 3x more vibration magnification too.
That's simply how it works.
This is why people out there that spend a fortune on tripods and heads that minimise/eliminate those variables too.

One last thing to also note(there always seems to be something to be mindful of or take note of!! :D) .. light quality also plays a part in determining contrast.
Contrast itself is the difference in lightness and tones between adjacent pixels.
Put it simply, if you had a red subject against a red background using red lighting as the main light source, your contrast levels would be extremely low, yeah!(think of it as a black subject in the dark .. you can't really see it well)
If you're image is simply black and white things, contrast is about as high as it gets. That is, you can't get higher contrast than a pixel level of 0(black) next too or against a pixel level of 255(white).
That is maximum contrast!
In your two images the one with the Sigma lens is shot in harsher light(sun is higher in the sky) .. contrast is to be expected to be higher under such lighting conditions.
With the Nikon 300mm image, it's seems obvious that the shot is taken either early or later(looks like later, but who knows) in the day. Setting sun, warmer light less contrast .. etc.
The old landscape photographer's saying of don't shoot between 10 and 2 or something comes to mind for those reasons just given. Midday light is harsh and contrasty. Landscape shooters all seem to want subtlety and warm tones .. etc.

I seriously think the difference you're seeing and showing is simply due to the lens settings described above, but if you take all possible variations of the causes into consideration and you make an assessment of the differences in image rendered, the 300mm setting of the 55-300 lens isn't all that bad really.
For a reasonably priced lens that can do a lot more than a fixed focal length lens can for half the money .. the little Nikon isn't half bad.
Knowing it's limitations helps to get more out of it and probably to expect less from it too.

**Unimportant final comment**
One last thing about Nikon kit type lenses, and they all seem to have the same issues/problems really.
Try to set the exposure compensation a bit brighter than you otherwise normally would.
That is, if you prefer exposures at 0Ev from your particular camera, then try using +0.3 or +0.7Ev with the Nikon lens fitted.
This is what I tend to find works better, to get more consistent exposures.
I have a ton of lenses that I like to play with, 99% of them are generally consistent in the way they expose.
The kit lens I have is too dark, (so I set camera to +ve compensation) and the only other lens that I find is different is the Tammy 24-70VC where it's always too bright.
I usually set -0.7 to -1.0 with the Tammy lens fitted.
As soon as one of those lenses is off and another more consistent lens is fitted, I then set the camera back to 0Ev(no compensation) until it's needed for a given situation.


.. hope that helps.

tandeejay
21-05-2016, 11:06am
Thanks Arthur, that is excellent information. And you've given me some great pointers on how to work within the limitations of my gear. Lots of info here for me to digest and try out.


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ameerat42
21-05-2016, 11:08am
Take a few more standardised shots and test it "properly".
These two tell you a cigarette-paper's-width about nothing much.

Lance B
21-05-2016, 11:32am
Arthur is correct. You are shooting wide open @ f5.6 on the 55-300 f4.5-5.6 and the 55-300 needs to be stopped down a stop (as do most lenses) to f8 to get the best sharpness and then possibly more if you want some Depth of Field as at even f8, there is little DOF at 300mm and f8. The trouble with stopping down even further is that you end up requiring a higher ISO meaning that will take the edge off sharpness as well. Welcome to the world of balancing shutter speed/aperture/ISO. :D With the 300mm photo, you have shot at 1/1250sec f5.6 and ISO 100, where you may get away with 1/600sec, f11, ISO 100. You do have VR on that lens, so you can safely shoot at an even slower shutter speed, maybe even down to 1/50sec with good technique, the only drawback is that any subject movement will then appear, like the waves will possibly be a blur. Again, you need to balance your shutter speed to whether subject movement is an issue. However, a little blur on wave movement may be a good thing to show motion.

The other problem with this comparison, is that isn't the Sigma a macro lens? If it is, then it is a VERY sharp lens and possibly not a fair comparison with the 55-300 f4.5-5.6 kit lens!

tandeejay
21-05-2016, 1:56pm
Take a few more standardised shots and test it "properly".
These two tell you a cigarette-paper's-width about nothing much.

Yep, I think your right... time to do some standardized testing using a tripod and exposure delay and anything else to eliminate external factors, rather than comparing two random shots taken at different times of days with different conditions.

- - - Updated - - -


Arthur is correct. You are shooting wide open @ f5.6 on the 55-300 f4.5-5.6 and the 55-300 needs to be stopped down a stop (as do most lenses) to f8 to get the best sharpness and then possibly more if you want some Depth of Field as at even f8, there is little DOF at 300mm and f8. The trouble with stopping down even further is that you end up requiring a higher ISO meaning that will take the edge off sharpness as well. Welcome to the world of balancing shutter speed/aperture/ISO. :D With the 300mm photo, you have shot at 1/1250sec f5.6 and ISO 100, where you may get away with 1/600sec, f11, ISO 100. You do have VR on that lens, so you can safely shoot at an even slower shutter speed, maybe even down to 1/50sec with good technique, the only drawback is that any subject movement will then appear, like the waves will possibly be a blur. Again, you need to balance your shutter speed to whether subject movement is an issue. However, a little blur on wave movement may be a good thing to show motion.

The other problem with this comparison, is that isn't the Sigma a macro lens? If it is, then it is a VERY sharp lens and possibly not a fair comparison with the 55-300 f4.5-5.6 kit lens!

Thanks Lance. I'll definitely keep more of an eye on aperture in future.

And yes, the Sigma is a macro lens. So probably best to do AM's suggestion of some standardized testing to work out the limits of the 55-300 so that I can aim to work within the limitations of my gear.

Cage
21-05-2016, 3:05pm
The other problem with this comparison, is that isn't the Sigma a macro lens? If it is, then it is a VERY sharp lens and possibly not a fair comparison with the 55-300 f4.5-5.6 kit lens!

Spot on Lance. The 105mm Macro is a prime lens and is as sharp as a tack, so not really comparing apples with apples. A lot of folk who have macro lens only ever use them for that purpose, but as you know the longer ones are also more than useful as a medium telephoto lens.

arthurking83
22-05-2016, 7:29am
Yep, I think your right... time to do some standardized testing using a tripod and exposure delay and anything else to eliminate external factors, rather than comparing two random shots taken at different times of days with different conditions......

If you do this and want to test it at infinity focus and end up doing it outdoors, be mindful of any wind/breeze on the day too. ie. do it on a nice still day.
Even tho you use a tripod and exposure delay/mirror lockup etc .. it's all of no consequence of it's a slightly breezy day!

You can account for any tripod inadequacies if the camera has the ability to counter those inadequacies. And it's very rare for most of use to have access to a tripod and tripod head that is literally rock solidly stable!
From about 300 or so mm you can clearly see this .. and by about 500mm you can easily visualise an inadequate tripod/head setup.

If you're curious to see it for yourself: take said tripod setup outdoors on a slightly breezy day, even if the breeze is only mild.
If your camera has liveview and or video ability, use this. set lens to 300mm and I suggest use video mode. take a 30sec video of a fixed subject that you KNOW doesn't move.
What happens in a slightly breezy day is that you will see some vibrations in the video at random moments in the timeline.
So for some part of the video it can be rock steady, then (due to the breeze) it will have this shimmy effect, which is simply vibration.
The problem is the randomness of it. Even with mirror up/exposure delay to counter mirrorslap, the random nature of what a breeze does to image sharpness is the issue. You just have no idea that's it's causing the vibration.
And don't assume that just because you're shooting with a high enough shutter speed that you are safe too.
That's the purpose of testing all this .. to know the limitations of your gear.

Lance B
22-05-2016, 10:30am
Spot on Lance. The 105mm Macro is a prime lens and is as sharp as a tack, so not really comparing apples with apples. A lot of folk who have macro lens only ever use them for that purpose, but as you know the longer ones are also more than useful as a medium telephoto lens.

Very true, they can be a great portrait lens, if a little revealing. ;)

jim
22-05-2016, 10:47am
Take a few more standardised shots and test it "properly".
These two tell you a cigarette-paper's-width about nothing much.

This. Given the posted photos the Nikon looks to be just as sharp where it should be (obviously the foreground will be softer). Though if the image from the Nikon lens is uncropped, it is certainly a bit soft.

Mark L
23-05-2016, 11:40pm
Has anyone mentioned camera shake for the second? The lens is good enough to get something sharp somewhere but I can't see where here.
Has anyone mentioned camera shake for the second?

tandeejay
24-05-2016, 6:55am
People seem to have discounted camera shake due to the high shutter speed


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ameerat42
24-05-2016, 8:26am
Camera shake, with other conjectures, does not matter in the light of more testing needed.
(Ie, I discounted "everything". The way prices go up these days, it's high time everything was discounted:nod:)

However, a cursory examination of the picture under slightly higher magnification in Photoshop shows no evidence of it.

Tands. That's the best I could get because when I click on either photo I get sent to a Yahoo Log-in page.

(Yes, same here! I thought why Yahoo:confused013)

arthurking83
24-05-2016, 9:13am
People seem to have discounted camera shake due to the high shutter speed
.....

Unlike Am, I never discount anything ... for as long as everyone elses prices are rising(why rock the boat huh? :p)

anyhow don't assume that high shutter speeds preclude camera shake from the equation(up to a point).
That is, even tho the 300mm shot was shot at 1/1250s doesn't automatically mean that camera shake isn't an issue!

Contrary to my above comment tho, I reckon Am is right in saying there is no obvious clues to any camera shake in the 300mm image tho.

ie. now that I've started to discount stuff .. hopefully all others will follow my(and Am's) lead and lower their prices too .. especially on the prices of lenses nowadays! :D

ameerat42
24-05-2016, 9:18am
Actually, AK, that may account for my being sent to Yahoo log-in when I click on the pictures.
- It's an unwanted freebie offered in lieu of a current inability of the market to lower prices on
the THINGS WE REALLY WANT:nod:

tandeejay
24-05-2016, 9:44am
Try the link now. I thought I'd solved the problem of making private images accessible on the forum with guest passes. Clearly, my method didn't work...


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tandeejay
24-05-2016, 9:47am
If you apply too much discount, you don't get the shake free model? :lol:


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ameerat42
24-05-2016, 9:48am
[Lo and behold!] They now work:D [/Lo and behold!]
Ta for that (and no longer tarred and feathered for what you had before:D).