Getting the best out of a 50mm 1.8 prime please?
Discussion
Following lots of posts on here and also reviews I recently bought a Nikon 50mm 1.8G AF-S prime for my D5100, primarily for portraits but anything else too.
I've used a it a few time since purchase on various "test" shots, of anything really, especially something with a sharp edge as one of the things I read was that these lens are very sharp. I managed a panorama on 5.6 and i have to say it was very sharp indeed.
Now for the portrait bit. I did a shoot on Friday with a couple young ladies - my god daughter and her friend. It was late afternoon and I wanted natural light, her dad held up a reflector for me. So far so Good. I took a variety of shots using 1.8, 2.2 and 2.8 as I needed to blur the background (back garden, very limited with what was achievable). On each time I aimed to use an eye as focus, and the camera appeared to have no problem finding focus and i took the shots.
Some 200+ shots later and into Lightroom we go.
Whilst many of the shots (especially the 2.8 aperture shots) were good - sharp eye, shallow DoF blurring the background etc, nearly all of the shots using 1.8 and 2.0 were not so good. They tended to be out of focus, or very soft.
I must confess I wasn't expecting that after reading the reviews and I am wondering if there is a trick to using the lens with 1.8 - 2.2 aperture, was I just s
te or should those apertures be avoided for portraits?
Is it possible that the lens is not quite right, although as I said it focuses sharp at 2.8 and above?
Also, as a learning point for me, when you take a head and shoulder portrait (filling the frame) and the model has their face slightly turned meaning one eye is slightly further from the camera than the other, is it common practice to use a higher aperture to increase doF to make sure both eyes are more in focus? In some of the shots I took one eye is ever so slightly out of focus, and i'm very self critical so notice it.
How do you experts approach such a shot please?
I've used a it a few time since purchase on various "test" shots, of anything really, especially something with a sharp edge as one of the things I read was that these lens are very sharp. I managed a panorama on 5.6 and i have to say it was very sharp indeed.
Now for the portrait bit. I did a shoot on Friday with a couple young ladies - my god daughter and her friend. It was late afternoon and I wanted natural light, her dad held up a reflector for me. So far so Good. I took a variety of shots using 1.8, 2.2 and 2.8 as I needed to blur the background (back garden, very limited with what was achievable). On each time I aimed to use an eye as focus, and the camera appeared to have no problem finding focus and i took the shots.
Some 200+ shots later and into Lightroom we go.
Whilst many of the shots (especially the 2.8 aperture shots) were good - sharp eye, shallow DoF blurring the background etc, nearly all of the shots using 1.8 and 2.0 were not so good. They tended to be out of focus, or very soft.
I must confess I wasn't expecting that after reading the reviews and I am wondering if there is a trick to using the lens with 1.8 - 2.2 aperture, was I just s
te or should those apertures be avoided for portraits? Is it possible that the lens is not quite right, although as I said it focuses sharp at 2.8 and above?
Also, as a learning point for me, when you take a head and shoulder portrait (filling the frame) and the model has their face slightly turned meaning one eye is slightly further from the camera than the other, is it common practice to use a higher aperture to increase doF to make sure both eyes are more in focus? In some of the shots I took one eye is ever so slightly out of focus, and i'm very self critical so notice it.
How do you experts approach such a shot please?
always post examples...
The nifty fifties often are not at their best wide open. it wont be as sharp ( if properly used) at 1.8 as it will at 2.8.
saying that it could be some other issues.
DOF at 1.8 is very slim so any focus inaccuracies get shown up very quickly. At 2.8 you have over twice the dof this can easily cover up some mis-focusing.
Two things you can do now, is check for accurate focus (centre point on a good subject that will show it ( railings, diagonal line of batteries etc). And check for how sharp it is at 1.8
Another issue is if you are focus and recomposing, this technique works well in general but for fast lenses with shallow DOF you shift the plane of focus enough that you mess it up. Try using focus points on the subject without reframing after focusing.
The nifty fifties often are not at their best wide open. it wont be as sharp ( if properly used) at 1.8 as it will at 2.8.
saying that it could be some other issues.
DOF at 1.8 is very slim so any focus inaccuracies get shown up very quickly. At 2.8 you have over twice the dof this can easily cover up some mis-focusing.
Two things you can do now, is check for accurate focus (centre point on a good subject that will show it ( railings, diagonal line of batteries etc). And check for how sharp it is at 1.8
Another issue is if you are focus and recomposing, this technique works well in general but for fast lenses with shallow DOF you shift the plane of focus enough that you mess it up. Try using focus points on the subject without reframing after focusing.
I'm almost certain that mine is technique. Using mine on a mirrorless camera I compose the shot, then using the touchscreen select the focus point. I then use the magnify function to zoom on the eyes and I think this faffing about makes me lose it. I sometimes wish I had a simple OVF with a nice small dot in it to use to focus. The EOS M uses a large rectangle as your focus point. 
I had a nice bit of light coming through the window the other day and quickly snapped my daughter. I liked the shots but was really annoyed that the eyes weren't in focus.
I had a nice bit of light coming through the window the other day and quickly snapped my daughter. I liked the shots but was really annoyed that the eyes weren't in focus.
There is a tendency, when trying one's first 'fast' lens, to slam it on max aperture and fire away. Unfortunately shallow DOF isn't always easy. First, the depth of field is - duh - shallow, meaning that the slightest error in focusing can lose the shot. Second, some camera AF systems are not perfectly accurate. You may not notice it at f5.6, but at f1.8 it shows. It's like buying better hi-fi speakers and realising suddenly your amp isn't as good as you thought. The slightest subject movement after the camera locks focus can lose the shot too. Third, no lens is at its best wide open - some softness is part of the deal.
Presume you're using the centre focus point? The way forward is to take more care, and/or to check your AF system/lens combo is working accurately (focus chart), and/or use a smaller aperture to give you more wriggle room. I have a 50mm f1.4 because it seemed a good idea at the time, but in practice it was unworkable. In reality if people are involved I try to stay at f3.5 or above.
That doesn't mean you're wasting f1.8; you'll get a brighter viewfinder and more accurate/less hunting AF in low light.
As for the eyes question, have a look at portraits you like and see what they've done.
Presume you're using the centre focus point? The way forward is to take more care, and/or to check your AF system/lens combo is working accurately (focus chart), and/or use a smaller aperture to give you more wriggle room. I have a 50mm f1.4 because it seemed a good idea at the time, but in practice it was unworkable. In reality if people are involved I try to stay at f3.5 or above.
That doesn't mean you're wasting f1.8; you'll get a brighter viewfinder and more accurate/less hunting AF in low light.
As for the eyes question, have a look at portraits you like and see what they've done.
It is really very difficult to work wide open doing head and shoulders portraits. The DoF will likely be absurdly thin and even then is not a depth of sharpness as of "acceptable sharpness" - which it may well not be if you are looking for razor sharp edges. (Not always a great look for a portrait of course, hence the "soft focus" lenses of old.)
I recall observing some flash demo sessions on portraiture where the photographer regularly explained how he was controlling the system around his chosen aperture for the portrait lens he was using. For the subject, sitting still on a chair at the point of shutter release, he was using f8. Always f8. The point at which image quality and required DoF came together for that lens and camera combination.
Of course being a pseudo studio session the light could be controlled easily and the subject was always pre-positioned far enough away from a plain background that the background was never going to impose itself on the image other than by way of brightness depending on if and how it was lit.
If head and shoulders portraits are the objective you are probably shooting from something like 1 metre away - perhaps a tad more.
At f1.8 on a Canon crop body (or M) that would give a DoF of about 2.6cm. If the top of the nose is sharp the nearest eye won't be. If you point of focus is half way down the nose you may almost get the nose and nearest eye looking almost sharp. The plane of focus may pick out all sorts of components of the image as looking sharper than stuff around them which often gives an undesired effect.
Even if you move back to 1.5 metres the DoF will only be around 6cms. And remember that the truly sharp bit is, more or less, on the centre of that DoF range.
With a Nikon crop body you get a couple of mm more notional DoF at 1 metre and about 3mm more at 1.5metres.
At f8 and a 1 metre distance your DoF will be nearer 11 to 12 cms - which is what, about half a head width? So assuming the head is slightly turned, "head on" being mainly the prerogative of mug shots, if you focus on the near eye you might, all being well, get the nose and far eye in acceptable focus too. Even better at 1.5 metres distance to the subject. It would probably provide enough latitude to compensate for small focus inaccuracies between the lens and body as well in most cases.
Using "Full Frame" with a 50mm will give greater DoF for the same fstop but, of course, the usually favoured portrait lens "length" is about 80 to 100mm - in effect the equivalent of a 50mm on a crop body. As a result the DoF numbers are very little different.
The wide lens was always great in film days before AF for enabling manual focusing in poor light before shooting with flash at a more "sensible" setting. Wide open on group shots and similar when flash was not available could also be acceptable - by the standards of the day - since the option was no shot at all - or the cumbersome concept of changing to a faster film. But for the modern digital era I think working wide open comes across a bit of a niche activity that one would not have tried much in film days given the cost of processing but can experiment endlessly using digital, should you so wish, because the per shot costs are perceived to be extremely low.
I recall observing some flash demo sessions on portraiture where the photographer regularly explained how he was controlling the system around his chosen aperture for the portrait lens he was using. For the subject, sitting still on a chair at the point of shutter release, he was using f8. Always f8. The point at which image quality and required DoF came together for that lens and camera combination.
Of course being a pseudo studio session the light could be controlled easily and the subject was always pre-positioned far enough away from a plain background that the background was never going to impose itself on the image other than by way of brightness depending on if and how it was lit.
If head and shoulders portraits are the objective you are probably shooting from something like 1 metre away - perhaps a tad more.
At f1.8 on a Canon crop body (or M) that would give a DoF of about 2.6cm. If the top of the nose is sharp the nearest eye won't be. If you point of focus is half way down the nose you may almost get the nose and nearest eye looking almost sharp. The plane of focus may pick out all sorts of components of the image as looking sharper than stuff around them which often gives an undesired effect.
Even if you move back to 1.5 metres the DoF will only be around 6cms. And remember that the truly sharp bit is, more or less, on the centre of that DoF range.
With a Nikon crop body you get a couple of mm more notional DoF at 1 metre and about 3mm more at 1.5metres.
At f8 and a 1 metre distance your DoF will be nearer 11 to 12 cms - which is what, about half a head width? So assuming the head is slightly turned, "head on" being mainly the prerogative of mug shots, if you focus on the near eye you might, all being well, get the nose and far eye in acceptable focus too. Even better at 1.5 metres distance to the subject. It would probably provide enough latitude to compensate for small focus inaccuracies between the lens and body as well in most cases.
Using "Full Frame" with a 50mm will give greater DoF for the same fstop but, of course, the usually favoured portrait lens "length" is about 80 to 100mm - in effect the equivalent of a 50mm on a crop body. As a result the DoF numbers are very little different.
The wide lens was always great in film days before AF for enabling manual focusing in poor light before shooting with flash at a more "sensible" setting. Wide open on group shots and similar when flash was not available could also be acceptable - by the standards of the day - since the option was no shot at all - or the cumbersome concept of changing to a faster film. But for the modern digital era I think working wide open comes across a bit of a niche activity that one would not have tried much in film days given the cost of processing but can experiment endlessly using digital, should you so wish, because the per shot costs are perceived to be extremely low.
Focus looks fked on those 2 posted, I dont think that's a lens issue based on what you've said in terms of how you're putting the focusing together.
If you're going to do that sort of thing you'll barely get away with it at f/4, needs rethinking tbh
On portraits, I really wouldnt be at f1.8 if you're in their faces either. It's OK if you step back a bit and then crop, but filling the frame as a headshot at a shallow dof isnt going to do anyone any favours. Head and shoulders down to roughly where the elbows are, you'll be OK at f/2, but not if you've filled the frame with face. You'll see the same issue though if you shoot say at 200mm at f/8, the far side of the face wont be in focus.
I'd have a rethink about how you're able to focus, where you're able to, step back a bit on composition for portraits and open the lens up a bit
ked on those 2 posted, I dont think that's a lens issue based on what you've said in terms of how you're putting the focusing together. If you're going to do that sort of thing you'll barely get away with it at f/4, needs rethinking tbh
On portraits, I really wouldnt be at f1.8 if you're in their faces either. It's OK if you step back a bit and then crop, but filling the frame as a headshot at a shallow dof isnt going to do anyone any favours. Head and shoulders down to roughly where the elbows are, you'll be OK at f/2, but not if you've filled the frame with face. You'll see the same issue though if you shoot say at 200mm at f/8, the far side of the face wont be in focus.
I'd have a rethink about how you're able to focus, where you're able to, step back a bit on composition for portraits and open the lens up a bit
Edited by andy-xr on Monday 2nd November 10:42
It would be interesting to know what AF settings you are using. I use single point, single focus for all portrait type stuff and my 35mm f1.8 is razor sharp on the D5100.
As for eyes, it's personal taste, but for me it is the eye nearest the camera that needs to be in perfect focus, you can get away with the other one being out.
I know it's hard but stop looking at everything at 100%, look at the picture as a whole and see if you are happy with it.
As for eyes, it's personal taste, but for me it is the eye nearest the camera that needs to be in perfect focus, you can get away with the other one being out.
I know it's hard but stop looking at everything at 100%, look at the picture as a whole and see if you are happy with it.
Thanks everybody for your replies, and advice - I'm pleased it's not just me. I will rethink my portrait shots! I have to say I have found the few portrait shoots I have done to be the most difficult type of photography. There is just so much to think about, even with willing models!
For portraits i set My camera to single shot single point focus, centre weighting, I was using the centre focus point and trying to get it stable on an eye, but I must confess it is perfectly possible that I may have wavered forward or backward a mm or few, something I have never even considered that before.
More practice I think and leave 1.8 for something else!
For portraits i set My camera to single shot single point focus, centre weighting, I was using the centre focus point and trying to get it stable on an eye, but I must confess it is perfectly possible that I may have wavered forward or backward a mm or few, something I have never even considered that before.
More practice I think and leave 1.8 for something else!
The 1.8 lenses are not that good to be fair.
In terms of wide open at 1.8 then they are very soft and I find myself not shooting below f2.8 .
Still get a nice bokeh effect but don't have an issue with soft focus stuff.
this is at f1.8 with a polarising filter
AF all taken
IMG_2035-3 by Fat Bear Photography, on Flickr
same camera, similar exposure and similar distance but at f2.5 - much sharper IMO
you can get some sharp images at f1.8 but it's such a faff i just can't be bothered anymore.
IMG_2111-15 by Fat Bear Photography, on Flickr
In terms of wide open at 1.8 then they are very soft and I find myself not shooting below f2.8 .
Still get a nice bokeh effect but don't have an issue with soft focus stuff.
this is at f1.8 with a polarising filter
AF all taken
IMG_2035-3 by Fat Bear Photography, on Flickrsame camera, similar exposure and similar distance but at f2.5 - much sharper IMO
you can get some sharp images at f1.8 but it's such a faff i just can't be bothered anymore.
IMG_2111-15 by Fat Bear Photography, on FlickrWhen I started out, I made the mistake that Rob and Simpo have pointed out.
It really is as simple as two or three metres away, at f1.8 if eyes are in focus, the nose won't be - even if the subject is looking straight on.
I quickly found that between f2.8 and f5.6 is about where there is enough leeway to get the most 'keepers' and have the whole face in focus. If you want the blurred background effect, all you need do is compose the shot where the background is further away, and thus more out of focus.
It really is as simple as two or three metres away, at f1.8 if eyes are in focus, the nose won't be - even if the subject is looking straight on.
I quickly found that between f2.8 and f5.6 is about where there is enough leeway to get the most 'keepers' and have the whole face in focus. If you want the blurred background effect, all you need do is compose the shot where the background is further away, and thus more out of focus.
Very few lenses are at their sharpest when wide open, most will reach peak sharpness when stepped down a little.
Unless you really need paper thin DoF (or are desperately strapped for light), the advantages in an f/1.8 lens lie in their light-gathering whilst focussing (lens is wide open whilst focussing, which means a brighter image so easier to achieve focus, also higher sensitivity with some bodies) and the fact that when you are at f/4 or f/5.6 etc, you are stopped down and thus should have a sharper image than if you were using an f/4 or f/5.6 lens.
Unless you really need paper thin DoF (or are desperately strapped for light), the advantages in an f/1.8 lens lie in their light-gathering whilst focussing (lens is wide open whilst focussing, which means a brighter image so easier to achieve focus, also higher sensitivity with some bodies) and the fact that when you are at f/4 or f/5.6 etc, you are stopped down and thus should have a sharper image than if you were using an f/4 or f/5.6 lens.
Do you get the same issue in live view?
A fast prime used wide open has a narrow depth of field as others have said, this can expose shorcomings of the phase AF of a camera body. Pricier bodies have an offset where you can tune this.
Live view uses Contrast based AF which should always be 100% accurate if slow. If it's bang on in Live View the lens is ok and your particular D5100 is a little off.
Not sure if this can be factory reset.
A fast prime used wide open has a narrow depth of field as others have said, this can expose shorcomings of the phase AF of a camera body. Pricier bodies have an offset where you can tune this.
Live view uses Contrast based AF which should always be 100% accurate if slow. If it's bang on in Live View the lens is ok and your particular D5100 is a little off.
Not sure if this can be factory reset.
Unless I'm desperately trying to blur out the background or shooting somewhere dark I aim for f/2.5 to 2.8 (more if the background is a good distance away from the subject as you still get decent bokeh), but can usually get away with f/2.2 with stationary subjects at a stretch.
As Simpo mentioned, selecting the centre AF point makes it a lot easier.
I don't think the 50mm f/1.8 lens is bad at all - in fact for the money I think it's difficult to beat - but it does take some time to get to grips with it's limitations and get used to working round them.
As Simpo mentioned, selecting the centre AF point makes it a lot easier.
I don't think the 50mm f/1.8 lens is bad at all - in fact for the money I think it's difficult to beat - but it does take some time to get to grips with it's limitations and get used to working round them.
xjay1337 said:
The 1.8 lenses are not that good to be fair.
In terms of wide open at 1.8 then they are very soft and I find myself not shooting below f2.8 .
Still get a nice bokeh effect but don't have an issue with soft focus stuff.
this is at f1.8 with a polarising filter
AF all taken
IMG_2035-3 by Fat Bear Photography, on Flickr
same camera, similar exposure and similar distance but at f2.5 - much sharper IMO
you can get some sharp images at f1.8 but it's such a faff i just can't be bothered anymore.
IMG_2111-15 by Fat Bear Photography, on Flickr
Have been looking for this thread and in particular your post for weeks now and finally found it, am very interested in the lens and the aperture setting you used. Thank you In terms of wide open at 1.8 then they are very soft and I find myself not shooting below f2.8 .
Still get a nice bokeh effect but don't have an issue with soft focus stuff.
this is at f1.8 with a polarising filter
AF all taken
IMG_2035-3 by Fat Bear Photography, on Flickrsame camera, similar exposure and similar distance but at f2.5 - much sharper IMO
you can get some sharp images at f1.8 but it's such a faff i just can't be bothered anymore.
IMG_2111-15 by Fat Bear Photography, on Flickr
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