Suggestions for affordable fast (f2 and less), and sharp wide open 50mm

[Henchman]

I am looking for a 50mm lens that's very sharp wide open.

I have a super takumar 50mm 1.4, but I need to stop it down to at least 2.8 to get it nice and sharp.

So what do you guys recommend for under $400.

[noone]

Used on?

[Henchman]

Sorry.

Using it with my Blackmagic pocket cinema camera 4k.

So, anything that is MFT or can adapt to it.

[kye]

On 8/12/2020 at 6:26 AM, Henchman said:

I am looking for a 50mm lens that's very sharp wide open.

I have a super takumar 50mm 1.4, but I need to stop it down to at least 2.8 to get it nice and sharp.

So what do you guys recommend for under $400.

Buy a 50mm F4 lens.  Virtually guaranteed to be sharp wide open.

[Henchman]

On 8/26/2020 at 5:46 PM, kye said:

Buy a 50mm F4 lens.  Virtually guaranteed to be sharp wide open.

That was literally no help at all.

[noone]

I have had a LOT of 50s and near 50s.

Very few are what I would consider sharp wide open though it is relative and none of the cheaper ones I have had would be.

MAYBE used on your camera they would be ok as they are not using the worst part of the lenses.

The best by far for me is the FE Sony Zeiss 55 1.8 which IS sharp wide open but that is no help to you.

One cheapy that i had and really liked was the Nikon 50 1.8 AF (non D made in Japan version).

Maybe any of the Nikon 50 1.8s? would be a reasonable combination of cheap/sharp enough?

IF you could find one in your price range, the FD 50 1.2 L (not the non L) is sharp in the area in focus at 1.2 and it is better stopped down a little so still fast.

The same with the Pentax 50 1.2 I had though no asperic elements in the Pentax there is in the FD L (those two might be too dear though.

[Henchman]

1 hour ago, noone said:

I have had a LOT of 50s and near 50s.

Very few are what I would consider sharp wide open though it is relative and none of the cheaper ones I have had would be.

MAYBE used on your camera they would be ok as they are not using the worst part of the lenses.

The best by far for me is the FE Sony Zeiss 55 1.8 which IS sharp wide open but that is no help to you.

One cheapy that i had and really liked was the Nikon 50 1.8 AF (non D made in Japan version).

Maybe any of the Nikon 50 1.8s? would be a reasonable combination of cheap/sharp enough?

IF you could find one in your price range, the FD 50 1.2 L (not the non L) is sharp in the area in focus at 1.2 and it is better stopped down a little so still fast.

The same with the Pentax 50 1.2 I had though no asperic elements in the Pentax there is in the FD L (those two might be too dear though.

I ended up picking up a voigtlander 40mm f/1.4.
not 50mm but close enough.

[kye]

4 hours ago, Henchman said:

That was literally no help at all.

Why, f4 lenses are sharp wide open, that was your criteria.

People often make the mistake of judging lenses wide open, but the problem is that not all lenses have the same largest aperture.

Sometimes the best way to get a lens that's sharp at a particular aperture is to get a lens with a wider aperture than your desired one.

[noone]

22 minutes ago, kye said:

Why, f4 lenses are sharp wide open, that was your criteria.

People often make the mistake of judging lenses wide open, but the problem is that not all lenses have the same largest aperture.

Sometimes the best way to get a lens that's sharp at a particular aperture is to get a lens with a wider aperture than your desired one.

Kye, sometimes f2 and faster are needed for valid reasons.    The OP stated they needed that so that was ALSO a criteria.

I agree about most (though not all) lenses are better stopped down.    The few exceptions are usually very expensive.

Often there is a bit of a myth about slower lenses being better than the faster version of same.

I would always take a good fast lens over a good slow one unless the size became unmanageable.

I do sometimes wish my very old A mount AF Sigma 180 5.6 macro lens was in Canon mount or Sony E as I would love to use it from time to time due to its small size (though my Sigma 150 2.8 macro is light years better).

[kye]

2 hours ago, noone said:

Kye, sometimes f2 and faster are needed for valid reasons.

Absolutely.  I have f0.95 primes, so you're preaching to the choir here!

2 hours ago, noone said:

The OP stated they needed that so that was ALSO a criteria.

Actually, they didn't.  Or at least, when I just re-read this thread five times looking for it, I couldn't find it!

2 hours ago, noone said:

I agree about most (though not all) lenses are better stopped down.    The few exceptions are usually very expensive.

Often there is a bit of a myth about slower lenses being better than the faster version of same.

True.

The issue I took, and thus my slightly sarcastic reply, was that this is viewed far too simplistically by people.

Take two hypothetical lenses, one is f1.4 and the other is f2.8.  Let's say that the f1.4 one isn't so sharp wide open, but the f2.8 lens is.

The traditional, one-dimensional, thinking is that if you want sharp images then the 2.8 lens is the one to go for because "the f1.4 is soft wide-open but the f2.8 lens isn't", end of story, and mostly, end of how deep the persons knowledge is about the subject.

The problem with this thinking is that the f1.4 lens might be sharper at f2.8 than the f2.8 lens is, but the sharp-wide-open one-dimensional thinkers don't go that far.

[noone]

1 hour ago, kye said:

 

Actually, they didn't.  Or at least, when I just re-read this thread five times looking for it, I couldn't find it!

The thread title?

Every lens is different and sometimes a slower lens may well be better at certain apertures than a faster one more usually it isn't (at least mine have not been).

[Henchman]

6 hours ago, kye said:

Why, f4 lenses are sharp wide open, that was your criteria.

People often make the mistake of judging lenses wide open, but the problem is that not all lenses have the same largest aperture.

Sometimes the best way to get a lens that's sharp at a particular aperture is to get a lens with a wider aperture than your desired one.

No, my criteria was fast and sharp.

 

[Henchman]

3 hours ago, kye said:

 

The issue I took, and thus my slightly sarcastic reply, was that this is viewed far too simplistically by people.

 

I asked a very clear question.

50mm, f2 or less and sharp wide open.

Pretty clear question.

f4 isn't f2.

[Henchman]

Question: "What's your favorite non-alcoholic drink?"

Kye: "Gin and Tonic'

[kye]

lol, the only place I didn't look was in the thread title! 😂😂😂

5 hours ago, noone said:

Every lens is different and sometimes a slower lens may well be better at certain apertures than a faster one more usually it isn't (at least mine have not been).

There's a pretty well established principle that lenses sharpen up when you stop them down the first couple of stops.  As mentioned before this has exceptions, but those exceptions seem to be just that, exceptions.

DXOMark has a lot of interesting lenses and you can look at the graph of sharpness (perceptual megapixels) vs aperture to see how much it sharpens up when stopped down.  Typically they look like this:

Where wide open they aren't as good as when closed down a couple of stops.

So in that sense, the target aperture really matters, as the best way to get a sharp image at f2 might be to buy an f1.2 lens.  

The exception is normally much slower lenses that have the same kind of optical performance as the above, only don't open the aperture as much.

[Henchman]

5 hours ago, kye said:

 

There's a pretty well established principle that lenses sharpen up when you stop them down the first couple of stops.  As mentioned before this has exceptions, but those exceptions seem to be just that, exceptions.

 

 

And that's exactly why I was asking for f2 or faster suggestions. So when I'm shooting in low-light conditions, I can still stop down a 1.4 lens to 2.8 and know I'll have a sharper image than using a 2.8 lens, wide open. 

 

And since this is for filmmaking, I'm mostly concerned about the center of the image anyway.

The Voigtlander is very sharp wide open at f/1.4. 

[kye]

6 hours ago, Henchman said:

And that's exactly why I was asking for f2 or faster suggestions. So when I'm shooting in low-light conditions, I can still stop down a 1.4 lens to 2.8 and know I'll have a sharper image than using a 2.8 lens, wide open. 

 

And since this is for filmmaking, I'm mostly concerned about the center of the image anyway.

The Voigtlander is very sharp wide open at f/1.4. 

Makes sense.  Getting a 2.8 that is sharp from f2.8 up would probably have been more expensive.  Of course, if you're cropping into the image circle then you're really only interested in the performance of the lens in the middle of its image circle.  

Unfortunately that's data that places like lens rentals publish, and not for that many lenses, as it's obviously very laborious to gather.

I ended up with the Voigtlander 42.5mm f0.95 prime.  Not sharp wide open, but almost as sharp as the competition when stopped down to their widest apertures, and can be used wide-open in a pinch.  Subjectively a bit of sharpening goes a long way to matching things, especially if you're degrading the image in post as well with halation or other softening effects.

[Stab]

- Sigma 50mm f1.4
- Rokinon / Samyang 50mm f1.4 - A bit softer in the corners at f1.4 and probably a bit more CA

[Yannick Willox]

Kamlan 50mm f1.1 mk2

Not so sharp at f1.1, decent at 1.4 and great from 2.8. I have it on one of my p4k almost every time.