Soft focus

donkeymusic

donkeymusic

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Carlo
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Hello,

Noticing recently that a lot of my photos are looking very soft.

Here is an example,
sample by Carlo Mullen, on Flickr

The focus was on the eyes but when zooming in the sharpness isnt there, and to offer a high quality product i feel this is something i need to overcome sooner, not sure where i am going wrong though.

I do also have another thread running with regards to improving sharpness in LR4 and PS

Any advice would be great. Thank you
 
Have you applied any sharpening to the image?

If you're shooting with flash you should up your shutter speed, that'll help with kids moving. At f8 I'd actually say you are heading away from sharp and into diffraction, on a crop at that kind of distance f5.6-f8 should be front to back sharp, but nothing comes out of the camera sharp, remember the softness is designed in.
 
Phil V said:
Have you applied any sharpening to the image?

If you're shooting with flash you should up your shutter speed, that'll help with kids moving. At f8 I'd actually say you are heading away from sharp and into diffraction, on a crop at that kind of distance f5.6-f8 should be front to back sharp, but nothing comes out of the camera sharp, remember the softness is designed in.
Click to expand...

What do you mean softness is designed in? Why would that be the case?
 
Phil V said:
Have you applied any sharpening to the image?

If you're shooting with flash you should up your shutter speed, that'll help with kids moving. At f8 I'd actually say you are heading away from sharp and into diffraction, on a crop at that kind of distance f5.6-f8 should be front to back sharp, but nothing comes out of the camera sharp, remember the softness is designed in.
Click to expand...

There was output sharpening applied to that image when i exported to upload as example.

the shot was in a studio using flash heads.
 
I'd guess that could be improved in post processing. Sharpening, and a bit more contrast and saturation.

It looks like missed focus, but it can't be. Is it a big crop? The other possibility is some movement blur as the lad is obviously not sitting still. Your effective flash duration could be as low as 1/300sec (which heads and power setting?). Do you have a more static shot showing the same problem?
 
HoppyUK said:
I'd guess that could be improved in post processing. Sharpening, and a bit more contrast and saturation.

It looks like missed focus, but it can't be. Is it a big crop? The other possibility is some movement blur as the lad is obviously not sitting still. Your effective flash duration could be as low as 1/300sec (which heads and power setting?). Do you have a more static shot showing the same problem?
Click to expand...

Have tried sharpening in LR4 but still when printed or exported, it gives a blurred image.

focus was on the childs eyes.

Big crop? nope that was pretty much as it was shot.

I have lencarta flash heads, and metering at 1/125 but not sure what output they have, in fact come to think of it not sure how the flash heads know to fire at 1/125, i have just always metered at this. There are no power settings other than the F stop settings.

He was sitting pretty still.
 
Robclarke said:
What do you mean softness is designed in? Why would that be the case?
Click to expand...

In front of the sensor there's an anti alias filter to stop moire patterns. This softens edges. Which is one of the reasons that SOOC isnt a good idea.

MF digital cameras, the Leica B&W camera and Kodaks FF digital dont have the filter, produce crisper images bit you have to be careful when shooting repeating patterns.
 
Looks like it is focussed slightly behind the face, if you look at the largest size on flickr the jumper to the left of his cheek is definitely sharper than his face. There could be some motion blur there too, as it looks like he was moving.
 
donkeymusic said:
Have tried sharpening in LR4 but still when printed or exported, it gives a blurred image.

focus was on the childs eyes.

Big crop? nope that was pretty much as it was shot.

I have lencarta flash heads, and metering at 1/125 but not sure what output they have, in fact come to think of it not sure how the flash heads know to fire at 1/125, i have just always metered at this. There are no power settings other than the F stop settings.

He was sitting pretty still.
Click to expand...

Hmm :thinking: You sure you didn't just miss the focus on that shot? What do the others look like? Are they all the same?

With flash, the flash duration is effectively your shutter speed but most of the cheaper studio heads are quite slow. Just guessing, but you're probably down to around 1/300-400sec-ish there in terms of comparable shutter speeds. Could be that.

Hard to say much from just that image, but if it's not just a one-off then other images will suffer in the same way. Do they?
 
killwilly said:
Click on the image and it will take you to their Flicker account, the full EXIF is in tact.
Click to expand...

I was checking it on my phone so only showed the camera name.
 
Try taping a letter to a table and setting the camera on a tripod looking down at an angle of 45° and use center focus point and take a few pis at different fstops and then check the results if you zoom into the center to check the results, the letters and words should be crisp and sharp at the focus point. Also check is is off as it will affect the image if its not needed and lock the mirror up to as it will avoid camera shake. When i did mine it was clear that the camera was focusing away from the piont of focus as the text was sharp around 2 lines away from the line it should have been i also checked with 3 different lens just to be sure it was a camera fault and not the lens

Hope that helps
 
mrodgers said:
Looks like it is focussed slightly behind the face, if you look at the largest size on flickr the jumper to the left of his cheek is definitely sharper than his face. There could be some motion blur there too, as it looks like he was moving.
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He wasnt moving for this shot but there are others where there is motion blur, i thought with studio lights, which is where i am slightly confused he wasnt moving much but i guessed that the studio lights would freeze him in motion.
 
HoppyUK said:
Hmm :thinking: You sure you didn't just miss the focus on that shot? What do the others look like? Are they all the same?

With flash, the flash duration is effectively your shutter speed but most of the cheaper studio heads are quite slow. Just guessing, but you're probably down to around 1/300-400sec-ish there in terms of comparable shutter speeds. Could be that.

Hard to say much from just that image, but if it's not just a one-off then other images will suffer in the same way. Do they?
Click to expand...

There are others from other shoots that are looking the same. Is there anyway to improve the shutter speed from the flash heads? These are Lencarta Smart Flash heads which i know are budget but wold have guessed they did the trick.
 
eddyc said:
Try taping a letter to a table and setting the camera on a tripod looking down at an angle of 45° and use center focus point and take a few pis at different fstops and then check the results if you zoom into the center to check the results, the letters and words should be crisp and sharp at the focus point. Also check is is off as it will affect the image if its not needed and lock the mirror up to as it will avoid camera shake. When i did mine it was clear that the camera was focusing away from the piont of focus as the text was sharp around 2 lines away from the line it should have been i also checked with 3 different lens just to be sure it was a camera fault and not the lens

Hope that helps
Click to expand...

will give that a whirl as well
 
donkeymusic said:
There are others from other shoots that are looking the same. Is there anyway to improve the shutter speed from the flash heads? These are Lencarta Smart Flash heads which i know are budget but wold have guessed they did the trick.
Click to expand...

I'm guessing it's subject movement then. You'd need to do some tests to confirm. Just get someone to sit still, and then compare to another shot with them moving a bit, and then a bit more, see what you get.

Nothing you can really do about it, other than buy a faster duration head. Studio flash durations are fastest at full power, so you might try that, but I doubt it'll make a massive difference. If active kids is something you shoot a lot, you're going to need summat else.

Nothing from Lencarta is really very quick. Fastest/cheapest I know that will do the job is probably Elinchrom BX250Ri. Or Bowens Pro range will take your existing S-fit modifiers.
 
HoppyUK said:
I'm guessing it's subject movement then. You'd need to do some tests to confirm. Just get someone to sit still, and then compare to another shot with them moving a bit, and then a bit more, see what you get.

Nothing you can really do about it, other than buy a faster duration head. Studio flash durations are fastest at full power, so you might try that, but I doubt it'll make a massive difference. If active kids is something you shoot a lot, you're going to need summat else.

Nothing from Lencarta is really very quick. Fastest/cheapest I know that will do the job is probably Elinchrom BX250Ri. Or Bowens Pro range will take your existing S-fit modifiers.
Click to expand...

I will test this over the weekend, bit disappointed that the flash heads are not good enough to freeze action, even though they are budget heads I would still expect them to do the job.

Bit confused on flash heads, when you say full power, on the Lencarta heads i can alter the power but then i am unable to control what i am metering to.

If i was too be looking at an alternative head and i presume i just need to change the key light, what spec. should i be looking at

Thanks for your assistance
 
donkeymusic said:
I will test this over the weekend, bit disappointed that the flash heads are not good enough to freeze action, even though they are budget heads I would still expect them to do the job.

Bit confused on flash heads, when you say full power, on the Lencarta heads i can alter the power but then i am unable to control what i am metering to.

If i was too be looking at an alternative head and i presume i just need to change the key light, what spec. should i be looking at

Thanks for your assistance
Click to expand...

Yes, do some controlled tests. I'm far from 100% sure the softness you're seeing is caused by subject movement and a slightly tardy flash duration, even though it fits your description of what you're getting. In your pic, the lad doesn't appear to be moving that fast. Need to check :thinking:

The subject of flash durations can get quite complicated and there's been a lot of discussion about it here recently. Nothing wrong with the Lencartas, they're typical of most studio heads. I would expect them to be okay with most things short of kids actually jumping about, and even then you'd most likely only get blurring on hands etc moving fast, and that usually looks fine. Maybe that lad has suddenly moved his head sideways? Dunno. The more I think about it the more I think you should look into it further.

Rule of thumb for flash durations is to take the quoted t.5 time and multiply by 2x or 3x to get an approximation of what the action-freezing potential looks like in terms of equivalent shutter speeds, but it's not an exact science because of the nature of the actual flash pulse. I also recall Garry was doing some practical tests to get more realistic figures, but I don't know any more than that.

It's the way that studio flash moderates light output which makes effective durations shorter at higher power levels (completely different to the way hot-shoe IGBT controlled guns do it). So you should do your tests at both high and low powers to see if it makes a significant difference. It will make some difference for sure, but how much varies from head to head. And yes, that makes light positioning difficult if you've always got to shoot flat out - that's why some manufacturers make faster duration versions of their heads. You may be able to get away with just the main key-light being shorter duration, depends on the set up, but technically but you'll still get some blurring against the slower background lights.

But do those tests. The evidence so far is not conclusive.
 
Scarecrow said:
I actually thought the opposite was true, as to give full power the flash duration is longer. At lower settings the flash doesn't need to be so long.
Click to expand...

No, you're thinking of IGBT controlled guns (ie all hot-shoe speelights). They always fire at full power, but at lower outputs the flash pulse is cut short. This can result in very short durations indeed, like 1/30,000sec at minimum output. And these numbers are 'real' in that they relate very closely to the kind of action-stopping potential you get with normal shutter speeds.

Studio-type heads work differently and at lower power outputs they simply charge the capacitors to a lower level. The result is the total flash burn time stays roughly the same (round numbers, about 1/200sec) but the peak brightness is lower. It is the peak of the flash that gives the action-stopping, and contributes most to the exposure, and that's what t.5 times attempt to measure (the length of time the brightness stays above 50% of peak). T.5 gets longer as power is reduced.

It's just that t.5 is a very inaccurate measure and compared to actual shutter speeds it's typically 2x to 3x shorter, flattering the flash performance. The t.1 time is a better estimate, but hardly anyone publishes those numbers.

To be fair, it's not an easy nut to crack, because what matters for action-stopping is not the total flash duration, but the height and duration of the peak. That's very hard to measure in a way that reflects actual use, with a method that could be reliably applied to all heads. I've compared dozens of different flash heads against actual shutter speeds in controlled conditions, and while that gives a very good idea, there's also an element of subjectivity in putting exact and hard numbers on what you're seeing.
 
thanks for you responses Richard.

I will plan to do some test shots over the weekend but am aware that other shoots where there has been little or no movement that the blurring has appeared which cause problems when trying to sell photos.

If there flash head isnt fast enough, then really can they be sold for studio work? or am i gonna need the subject sat perfectly still?

Thanks
 
donkeymusic said:
thanks for you responses Richard.

I will plan to do some test shots over the weekend but am aware that other shoots where there has been little or no movement that the blurring has appeared which cause problems when trying to sell photos.

If there flash head isnt fast enough, then really can they be sold for studio work? or am i gonna need the subject sat perfectly still?

Thanks
Click to expand...

Do your tests. Movement blur is just one possibility and should be considered given, IMHO, the apparent absence of other obvious causes and the fact that the lad looks like he's moving. If it was a sudden jerky movement, then flash duration could be a cause. Lencarta flash durations are very much in line with other heads around that price, and perfectly good enough for most studio subjects.

If you need something significantly faster, it will cost a lot more money. And if you have kids or athletes and dancers as regular subjects, then you should certainly consider that. But for more common subjects, just sitting/standing and moving around normally, you should have no problem at all. Maybe a fleeting gesture, the odd twitch, might show up, but you can live with that - often looks good in fact, adds to the impression of movement, so long as faces are nice and sharp.

Are you hand-holding? How steady are you? IS on? Shouldn't be a problem with that 50mm lens, but could be. IMO, the pic should be sharper than it is. I don't think it's diffraction, so that leaves only missed focus (unlikely at f/8), subject movement or camera shake related to flash duration.

PS Have you dropped the lens? Any possible damage there?
 
Carlo,

Richard has made some very good suggestions, you need to take them on board and carry out meaningful tests - it's pointless doing the same things time and time again in the hope that problems will resolve themselves, they won't.

Forget about live subjects for now, photograph a stationary object, see if the problem is still there - and a printed page or similar, at an angle, is an excellent subject because it will show you not only whether or not it is in focus, but also exactly where the focus point is. Try it at a wide aperture too, which won't hide errors.

If it's still unsharp, you either have a focussing problem or camera shake. Try it again with the camera on decent tripod. If the problem has now gone, then the lens is OK, the focussing is OK and you're left with either subject movement or camera shake.

Camera shake can be a much more common problem than a lot of people realise. I'm lucky, I can hold a camera very still (probably due to a lifetime of experience of holding rifles very still) but a lot of people can't. If that's your problem then you need to either learn how to breathe and hold the camera still, or use a tripod.
 
Phil V said:
Have you applied any sharpening to the image?

If you're shooting with flash you should up your shutter speed, that'll help with kids moving. At f8 I'd actually say you are heading away from sharp and into diffraction, on a crop at that kind of distance f5.6-f8 should be front to back sharp, but nothing comes out of the camera sharp, remember the softness is designed in.
Click to expand...

Nonsense
 
jamesLglass said:
Nonsense
Click to expand...

I'm afraid I'm a bit thick and would appreciate a fuller description of what is 'nonsense' as just a one word aggressive response looks a lot like trolling and I'm sure you're a nice guy really:)
To help you I posted 4 points:

F8 being a small enough aperture to have gone beyond the 'sweet spot' of an f1.8 lens (got the lens wrong - oops it could be around the sweet spot - don't know the lens personally)

F8 being a small enough aperture for less than critical focussing

Camera or subject movement is more likely than misfocus the SS is too low

The use of AA filters softens images.

Happy to discuss any of the above - Phil
 
Phil V said:
I'm afraid I'm a bit thick and would appreciate a fuller description of what is 'nonsense' as just a one word aggressive response looks a lot like trolling and I'm sure you're a nice guy really:)
To help you I posted 4 points:

F8 being a small enough aperture to have gone beyond the 'sweet spot' of an f1.8 lens (got the lens wrong - oops it could be around the sweet spot - don't know the lens personally)

F8 being a small enough aperture for less than critical focussing

Camera or subject movement is more likely than misfocus the SS is too low

The use of AA filters softens images.

Happy to discuss any of the above - Phil
Click to expand...

It's not diffraction. F/8 should be very close to the sweet-spot of any DSLR lens, in the centre at least. Unless the lens is faulty, or the image heavily cropped (apparently not) it should be pin sharp. And diffraction would effect every shot at f/8.

Shutter speed makes no difference to movement blur with flash, only the flash duration.

AA filters make very little difference to sharpness. They hardly reduce sharpness even at a critical level, and they don't eliminate moire completely either. And it would effect every shot.

TBH I don't know for sure why the OP's shot is not as sharp as it should be, based on one pic and some fairly vague comments that it's not the first time. But IMHO it can only be either accidentally missed focus, subject movement, or camera shake.
 
Phil V said:
I'm afraid I'm a bit thick and would appreciate a fuller description of what is 'nonsense' as just a one word aggressive response looks a lot like trolling and I'm sure you're a nice guy really:)
To help you I posted 4 points:

F8 being a small enough aperture to have gone beyond the 'sweet spot' of an f1.8 lens (got the lens wrong - oops it could be around the sweet spot - don't know the lens personally)

F8 being a small enough aperture for less than critical focussing

Camera or subject movement is more likely than misfocus the SS is too low

The use of AA filters softens images.

Happy to discuss any of the above - Phil
Click to expand...

Sorry I apologise I have had a long day.. As hoppyuk said f8 is around the sharpest aperture of a lot of lenses that's the only reason I said nonsense was because IMO diffraction doesn't happen till stopped down further. Again I apologise for that :-)
 
HoppyUK said:
It's not diffraction. F/8 should be very close to the sweet-spot of any DSLR lens, in the centre at least. Unless the lens is faulty, or the image heavily cropped (apparently not) it should be pin sharp. And diffraction would effect every shot at f/8.

Shutter speed makes no difference to movement blur with flash, only the flash duration.

AA filters make very little difference to sharpness. They hardly reduce sharpness even at a critical level, and they don't eliminate moire completely either. And it would effect every shot.

TBH I don't know for sure why the OP's shot is not as sharp as it should be, based on one pic and some fairly vague comments that it's not the first time. But IMHO it can only be either accidentally missed focus, subject movement, or camera shake.
Click to expand...
Yep - but why wouldn't a higher shutter speed help with subject movement / camera shake (genuine question)?

1/125 isn't the highest he could go (although 1/160 is a bit poor for a modern camera)
 
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Phil V said:
Yep - but why wouldn't a higher shutter speed help with subject movement / camera shake (genuine question)?

1/125 isn't the highest he could go (although 1/160 is a bit poor for a modern camera)
Click to expand...
It depends.
In a pro studio with no daylight coming in, the only light is from the modelling lamps and any overhead lighting, therefore there won't be any significant contribution to the exposure from that amount of light.
So, a small amount of light that barely registers won't create camera shake (well, technically it might, but you won't see it)

If it isn't a pro studio and there is daylight coming in then there could be enough ambient light to affect the exposure, so camera shake visible from that light is a possibility.

Like everything else, don't take my word for it - test it for yourself. Take a shot at f/8, 1/125th sec, no flash, and see whether there is enough of an image on the sensor to make any difference. If the sensor is black or close to black, you can rule it out as a possible cause.
 
Phil V said:
Yep - but why wouldn't a higher shutter speed help with subject movement / camera shake (genuine question)?

1/125 isn't the highest he could go (although 1/160 is a bit poor for a modern camera)
Click to expand...

Because the flash duration is the effective shutter speed. It wouldn't make any difference if the shutter speed was longer still. Assuming a normal level of ambient light, which I think is the case in DM's studio - the flash output is way brighter.

Shutter opens fully, flash fires. Brightness rises very rapidly to a peak, and that's what does the action-stopping. Then the flash fades more slowly (this is the bit that may possibly be creating movement blur) but it's still completely over and done with in say 1/200sec total, with the critical peak time being half of that or less, depending on the flash unit and power setting.

Even if DM could run at 1/250sec x-sync it would make zero visible difference, but he may not be able to do that even if the camera allowed, depending on the trigger. They often introduce a tiny delay, meaning that running at max x-sync shows a black band at the bottom.
 
Not been back to test this but yesterday i was exporting some files and noticed that any where the like th posted photo that were headshot appeared to be oof where as any that was head to toe and still focussed on the eyes appeared to be all in focus
 
could well be that, is there anyway around that other then improving my camera holding
 
been mad busy so not had chance to look into this again, think it will be xmas experiment.

It has got me thinking, and wondered if it could be a habit i gotten into.

Okay, i focus on the subjects eyes, using auto focus and centre spot, i then compose the shot holding the fire button halfway. What I think I am also doing is zooming in or out as part of composing the shoot and im wondering if the auto focus is then lost, so that there is no focus when i am taking the shot???
 
From that description can I recommend, back button focussing and if your camera has decent off centre focus pointsyou could try them too.
 
donkeymusic said:
been mad busy so not had chance to look into this again, think it will be xmas experiment.

It has got me thinking, and wondered if it could be a habit i gotten into.

Okay, i focus on the subjects eyes, using auto focus and centre spot, i then compose the shot holding the fire button halfway. What I think I am also doing is zooming in or out as part of composing the shoot and im wondering if the auto focus is then lost, so that there is no focus when i am taking the shot???
Click to expand...

Doing as you've described is a sure way to miss-focus. Which is exactly what your OP pic looks like - it's just that it seemed very unlikely given the f/number.
 
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