# Question About Prime Lenses



## bryanwstai (Jan 30, 2017)

Hey photographers, I've been playing around with my kit lens on my crop sensor D3000 for a year now and find that I enjoy taking portraits.
I've been looking at the 50mm prime lenses as I've heard they're good for portraits, but I hope to clarify a few things I'm not sure of, please bear with this beginner.

1) Since my camera is a crop sensor, is 50mm a good focal length for portraits? I heard that it'll be a 75mm since it's on crop sensor.
I usually like taking portraits like these (If i'm violating any rule by posting links, please remove):
http://i.imgur.com/yApMXcq.jpg *or* http://i.imgur.com/7WmX4gL.jpg

2) I'm on a relatively tight student budget as I'm still in uni. Should I opt for the f/1.8 instead of the f/1.4? The price of the f/1.4is almost double the f/1.8, understandably though.

Models that are compatible with my D3000 that I'm looking at are:
1. Nikon AF-S Nikkor 50mm f/1.8G @ AUD235 (or should I get the f/1.8D since it's cheaper?)
2. Nikkon AF-S Nikkor 50mm f/1.4G @ AUD504 (pricey for my budget)

Thanks a lot in advance,
Bryan.


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## Frank F. (Jan 30, 2017)

The first portait I would shoot with a 35mm FX or eqivalent ... 24mm on DX

The second portrait I would shoot with a 60mm to 105mm FX or equivalent. So 40mm or 70mm on DX.

If you want to shoot both with the same lens a 24-70 or 24-85 would be nice for you.

For the first shot a larger DOF is required anyway, for the second the piczure could profit from a wider opening. A 1.8/85 would be nice on FX or the 1.4/105. Both are out of your budget. 

Question. Does it have to be Autofocus?

Is manual focus an option?


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## bryanwstai (Jan 30, 2017)

Frank F. said:


> is manual focus an option



Hi Frank, 
Thanks for the quick and detailed answer! 

Yes I am open toward manual focus options


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## Frank F. (Jan 30, 2017)

I only use primes and use them on DX and FX as well.

As  you need two lenses and you already seem to have some kind of wider Zoom lens I would recommend you look into the longer option. I took a lot of portraits with the old 1.8/50 "D" type. The "G" type is much better. 

I do not recommend the 1.4/50G. In fact I had it and sold it to buy the 1.8/50G. Now I also got the 1.4/58G which was 900 Euros used so way out of your budget.

If a longer lens is an option there are a lot of great 80mm 85mm and 105mm manual lenses within your budget. But these are good for outdoors or big rooms on the DX crop format.


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## astroNikon (Jan 30, 2017)

When looking at lenses you will have to also know which ones are fully compatible with your camera.

Your D3000 is a entry level consumer camera.  It's missing a feature called an "in-body focus motor" which allows it to AutoFocus on lenses designated as "AF" or "AF-D"

Your D3000 can only autofocus on "AF-S" lenses, as these lenses have a focus motor built into the lens it self and thus does not need an in-body focus motor.  

The D3x00 and D5x00 are the modern cameras that require AF-S lenses.
The d7x00, d500 and all the FullFrames have the in-body focus motor and can AF on the older lense (though not the MF lenses of course).


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## jcdeboever (Jan 30, 2017)

I love my 35mm 1.8g. it's more versatile than the 50mm on  crop sensor. Excellent in tight spaces. Wide enough to get more into frame for street and landscape. Just have to watch out for getting in too close, minimum focus distance is just short of 12". Get in that close, you fatten up faces, so stay back a little.


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## table1349 (Jan 30, 2017)

bryanwstai said:


> 1) Since my camera is a crop sensor, is 50mm a good focal length for portraits? I heard that it'll be a 75mm since it's on crop sensor.



You heard one of the common myths.  Focal length is Focal length period.  Sensor size does not change focal length.  A 50mm is a 50 mm.  What you are getting on a crop sensor is the field of view that falls on the sensor is approximately equivalent to what a 75mm lens would produce.







Personally I prefer the 85 to 100mm range for portraits on either a FF or a crop for the particular characteristics of that range.




Various focal lengths shooting the same subject filling the frame as close to the same as possible.

As for which 50mm, since I don't shoot Nikon these days others would be better suited to answer whether to spend the extra on the f1.4 vs the f1.8.  If you were shooting Canon then the choice is easy, the f1.4 is far better.

I would suggest that when the budget allows, if you still want a 50mm in your arsenal of lenses look at the Sigma Art 50mm f.14: Sigma 50mm f/1.4 DG HSM Art Lens for Nikon F 311306 B&H Photo


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## dunfly (Jan 30, 2017)

If I was looking for a general walk around Prime, I would (and did) go with the 35mm/1.8, but if portraits are your main concern, I would go with the 50mm/1.8.  At the longer effective field of view of a 75mm, you are less likely to get to close and get facial distortion (big nose syndrome).  The 1.8 will give you good bokeh and should be plenty of aperture for most applications.  IMHO the 1.4 is not worth the price unless you are really interested in low light situations.

gryphonslair99 is correct, the crop sensor does not make a 50mm lens a 75mm lens, it just gives you the same field of view as a 75mm lens on an FX camera.  You will not get the exact same picture taking the same image with a 50mm on a crop sensor as 75mm on a full frame sensor.  As he illustrated, it is more like cropping the image down after it is shot.


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## greybeard (Jan 30, 2017)

You have part of the answer already with your kit zoom.  Experiment with it set to 50mm or 35mm and see what works best for you.  

Be sure to get an AF-S model with the focusing motor built into the lens as your camera body won't auto focus with AF or AF-D lenses.  You can of course, focus manually with AF or AF-D lenses.

You won't SEE a pixels difference in a 50mm f/1.8 and the 50mm f/1.4 so go for the f/1.8 if it fits your budget better.


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## petrochemist (Jan 30, 2017)

On full frame 50mm is really too short for head & shoulder portraits. On your crop camera the 75mm equivalent FOV is OK for portraits, though still slightly on the short side of the recommended optimum (85-105mm FF equivalent is quoted in several sources). If on a tight budget an older manual 50/1.8 should be a reasonable compromise, as these can be very cheap and are close to the ideal FOV.

If you're doing full length portraits you can get away with wider lenses than the standard portrait lengths. The important thing is how close you are to the subject, with a wide lens you need to get rather close to fill the frame, and this gives unnatural perspective.


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## greybeard (Jan 30, 2017)

gryphonslair99 said:


> bryanwstai said:
> 
> 
> > 1) Since my camera is a crop sensor, is 50mm a good focal length for portraits? I heard that it'll be a 75mm since it's on crop sensor.
> ...



This is a really nice and informative set.


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## Frank F. (Jan 30, 2017)

gryphonslair99 said:


>




Very nice example of how perspective changes distortion, independent of the lens used.

The shown efffect is only dependent on the distance between subject and camera, not upon the lens used.

That said: A longer focal length means of course a wider subject distance to fill the frame


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## table1349 (Jan 30, 2017)

Frank F. said:


> gryphonslair99 said:
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Actually the effect remains constant, the ability of the observer to detect the difference is dependent on the distance between subject and camera.


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## chuasam (Jan 30, 2017)

get the 50mm f/1.8G
the Nikon 50mm f/1.4G is a horrible lens for the money.
I have one (it was a gift) and it's neither sharp nor cheap.


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## Derrel (Jan 30, 2017)

Since you shoot the D3000, I would go for the 50mm* f/1.8* AF-S G lens instead of the D-series. I own both 1.8 versions, and the optics of the newer G-series are a little bit better; not by huge margins, but the G-series lens will autofocus with your camera, and that is important for action work, and for getting the exact, right focus set, whiich is very important at portrait ranges with a 50mm lens.

I see little reason to go for an f/1.4 lens in your situation. The f/1.8 G-series and its f/1.4 counterpart are close overall, and many people would call it a virtual toss-up, so, save the extra money, and buy the less-costly 1.8-G model. I really do NOT advocate shooting wide-open with a 50mm for portraits, but more around f/2.8 to f/3.5, and down to f/5.6 most of the time, so the issue of lens "speed" in a 50mm lens is for me, a theoretical consideration mostly.

It is no longer the 1960's or 1970's: the f/1.4 50mm or f/1.4 85mm lenses in the new G-series are really not noticeably better than the f/1.8 versions.


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## bryanwstai (Jan 30, 2017)

Thanks for the input guys, seems like the majority favours the 50mm f/1.8G. I found   a relatively cheap one at 200AUD
Link: Nikon AF-S NIKKOR 50mm f/1.8G Lens (PRIORITY DELIVERY) BecexTech Australia | Digital Cameras, Lens, Phones, Tablet Global Premier Retailer

Also, what do people think about the 24-70mm 2.8 zoom lens the first poster suggested? Will 2.8 still produce a decent bokeh? ( Just a thought not going to consider this at this stage)


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## greybeard (Jan 30, 2017)

gryphonslair99 said:


> Frank F. said:
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> 
> > gryphonslair99 said:
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Exactly, you can get the same effect with a single prime and cropping.  Back in the bad old days of film, all I had was my SRT201 and my 50mm 1.7.  I would set my lens to f/2.8, shoot my portrait with the camera in the horizontal position centering the head and shoulder top to bottom, and then crop to vertical.  The perspective was always perfect.


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## Derrel (Jan 30, 2017)

bryanwstai said:
			
		

> SNIP what do people think about the 24-70mm 2.8 zoom lens the first poster suggested? Will 2.8 still produce a decent bokeh?



Huge, overly-long lens that scares people off, or makes them think you are some kiund of a perv. Average optics compared to single focal lenght lenses. The long end of 70mm is NOT quite long enough to really give a tele-look. Heavy. Bulky. A lens that screams, "Look at th giuy with the BIG lens and the tiny *****!" Seriously...this is a lens category that's guaranteed to give you lots of average images. it's "safe".

The 24-85mm lenses Nikon has made? There have been several, made in various eras. The last two models in AF-S (the most-recent  being a kit zoom with VR for the D600 at first) are much smaller than the 24-70/2.8 models, and more easy to carry, less-threatening,less-obnoxiuous to subjects, and better for walkaround use. The difference between 70 and 85mm is fairly noticeable.

I'd ease up on the bokeh issue. And as for bokeh...the 24-70 models have average bokeh. Not very pretty.

On crop-body cameras a 24-70 is an odd bird.


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## Frank F. (Jan 31, 2017)

Derrel is right on the 24-70. I would not use these drastic words but the lens is a picture machine. Safe, reliable, fast AF, sharp, contrasty ... IMO no charme.

Like a HiFi component with rather cool analytical sound. That is why newspaper people love the lens. It delivers. Not more. Not less. The charme you might add in post.


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## bryanwstai (Jan 31, 2017)

Thanks for all the suggestions guys, really appreciate it, I think I've finally found a forum to stay and be a part of 

I'll be getting the Nikkor AS-F 50mm f/1.8G as posted in my link a few posts above!


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## table1349 (Jan 31, 2017)

First let me point out that I am not necessarily  disagreeing with Derrel's points on the 24-70, rather offering a different experience.  I own the 24-70 (canon) and use it quite a bit on my crop sensor body as well as my ff body with no difficulties.  I don't find it to be odd in my hands.  Perhaps that it because I am used to from my film days switching from MF to 35mm and back.  With the 24-70 my brain just goes into compensation mode and my feet just put me where I need to be, even if it is a bit different from what most people consider "standard" working distance.  

As to the quality of the Nikon 24-70, that I can not comment on.   My film days were centered around Nikon F's & F2's and Pentax 6X7's.  Digitally I shoot Canon.  

The point of this is, don't fall into the trap that everything is rigidly structured.  There is no one standard working distance.   Sure portraits with a 400mm f2.8 can be a little exasperating.   But for some shoots with college athletes I have used it as we were outside and the results we outstanding.   Besides no one minded the bit of yelling it took to give directions in that environment.


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## DanOstergren (Feb 1, 2017)

A 50mm f/1.8 on a cropped sensor served me well for portraits for a while, but to be honest, I much prefer an 85mm focal length for portraits, even on a crop sensor camera. I know you weren't asking about 85mm, but if you can get one instead of a 50mm, I think you should.


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## bryanwstai (Feb 2, 2017)

DanOstergren said:


> I know you weren't asking about 85mm, but if you can get one instead of a 50mm, I think you should.



Hi Dan! Thanks for suggesting this lens 
Why do you prefer the 85 over the 50? Are there any advantages as compared to the other?

Cheers,
Bryan.


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## DanOstergren (Feb 2, 2017)

bryanwstai said:


> DanOstergren said:
> 
> 
> > I know you weren't asking about 85mm, but if you can get one instead of a 50mm, I think you should.
> ...


The 85mm focal length has a way of compressing the background in a way that is very flattering for portraits.


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## dasmith232 (Feb 2, 2017)

Something else that I like about the 85 prime is that (in the f/1.8 version), it's a really small and lightweight lens. It's kind of refreshing to use that lens compared to the 70-200/2.8 when set to the same focal length for various situations.


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## Peakapot (Feb 2, 2017)

Frank F. said:


> For the first shot a larger DOF is required anyway



Can someone explain this please. 



Sent from my Nexus 6P using ThePhotoForum.com mobile app


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## Frank F. (Feb 2, 2017)

Peakapot said:


> Frank F. said:
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> > For the first shot a larger DOF is required anyway
> ...




If you want to have the legs, the arms and the head of the model in focus, you have to increase depth of field, so you close the aperture to 8 or 11.

In that case it is not terribly important if the largest aperture available is 1.4 or 5.6.

If you want only the eyes in focus and the rest unsharp / blurred then a wide aperture like 1.4 is better for you.


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## bryanwstai (Feb 2, 2017)

Frank F. said:


> so you close the aperture to 8 or 11



Sorry if the answer is obvious, but by closing the aperture that high in order to focus on the body as well, how do you then achieve the shallow dof?


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## kundalini (Feb 2, 2017)

I consider the 50mm to be very... beige.  Not too pretty and lacks any seasoning.  IMO, the 85mm as Dan mentioned, at least adds salt and pepper to the dish.


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## bryanwstai (Feb 2, 2017)

kundalini said:


> I consider the 50mm to be very... beige



Hey kundalini, thanks for the reply  The reason I'm getting a 50mm now is because i'm currently using a DX camera. I figured when I upgrade to the FX I would buy a 85mm then.


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## table1349 (Feb 2, 2017)

bryanwstai said:


> Frank F. said:
> 
> 
> > so you close the aperture to 8 or 11
> ...


The easiest way is to understand the math behind DOF.  The second easiest way is this.      Basically Plug and Play.


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## bryanwstai (Feb 2, 2017)

gryphonslair99 said:


> The second easiest way is this.


Thanks for the link gryphon, got some values which I was confused about and tried reading the bottom bit with the information but I'm still confused. What I got out of that was that the circle of confusion defines the amount a point needs to be blurred to be unsharp etc.

But how do you use those actual values in a practical situation? Are you meant to?

eg. 
Nearest Acceptable Sharpness: 1.94m     (Max/min distances you should stand fromyour subject?)
Furthest Acceptable Sharpness: 2.06m
_Total Depth of Field_: 0.12m

for a DSLR 1.5x CF and a 50mm lens at f/1.8


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## Frank F. (Feb 3, 2017)

bryanwstai said:


> Frank F. said:
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> 
> > so you close the aperture to 8 or 11
> ...



By opening the aperture!

As you calculated above at f/1.8 the 50mm lens on a crop sensor delivers 12cm DOF.
The 105mm on a  Full Frame Sensor at f/1.4 *at the same distance* delivers 3cm DOF.

In your first picture you have a 3/4 body portrait on a balcony, so you need something like one meter of DOF, so I would take a 24mm on a crop sensor, *still the same distance* and get 118cm DOF @f/4.0. On a full frame sensor with a 35mm lens I only achieve 80cm of DOF @f/4.0, so I close to f/5.6 and get 117cm of DOF.

That is called "equivalence" by some people although the term is misunderstood by many people


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## droaingsong (Feb 3, 2017)

Frank F. said:


> bryanwstai said:
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> > Frank F. said:
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That is an equivalent answer for "equivalence" . I learned something new today.


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## droaingsong (Feb 3, 2017)

greybeard said:


> gryphonslair99 said:
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> > bryanwstai said:
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So true. Didn't knew Sigma Art 50mm f/1.4 can be used for this.


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## bryanwstai (Feb 4, 2017)

Frank F. said:


> *still the same distance* and get 118cm DOF @f/4.0. On a full frame sensor with a 35mm lens I only achieve 80cm of DOF @f/4.0



Thanks Frank! I've got the jist of it now and have been reading up more about it. Just one quick question, you mentioned the first picture would require and approximate DOF @ ~1metre. How did you come up with that estimate? 

Thanks,
Bryan.


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## Frank F. (Feb 4, 2017)

bryanwstai said:


> Frank F. said:
> 
> 
> > *still the same distance* and get 118cm DOF @f/4.0. On a full frame sensor with a 35mm lens I only achieve 80cm of DOF @f/4.0
> ...



I estimated the distance from her knee to her hair and added something for insecurits focussing. If you are experienced you can do this shot with f/4
The second shot can be done at f/1.4 to f/2.8, depending on experience

more portraits @f=1.4


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