Is it possible to process a 24mm portrait to look like 50mm

[whitedragon101]

The iPhones best lens is 24mm. Is it possible to take a full sensor 48mp 24mm image close up (head and torso) and digitally process it somehow to look like it was taken with a 50mm?

I.e not have the enlarged nose and fall off in the sides of the face

 

[OldMacs4Me]

Back away and crop.

I seriously doubt that those 48mp capture 48mp of data, but should be good enough to do a soft portrait.

 

[coolguy4747]

almost anything is technically possible with digital manipulation, but the amount of effort it would take does not seem worth it, and that amount of manipulation would likely negate any benefit of the full sensor's worth of data

 

[Ben J.]

Any decent photo software can do this easily.
Look for "lens correction, skew, distort" etc.

 

[MacNut]

Why would you want to do this?

 

[notrack]

Not entirely. The difference between 24 and 50mm is not only the wieder angle of view but mainly the relative distance and angle between the camera and the elements in the image (nose, eyes, ears, background). With a wider lens you need to get closer to the subject. By that, the angle which you are looking at e.g. the ears is different than if being farther away. You can’t correct that in post.
The other point is the size of nose, eyes, ears etc relative to each other. Let’s say you are extremely close a foot or so from the face, then the ears would be almost twice as far away than the nose, hence the size difference.

Bottom line is that th focal length of the lens is secondary but the distance ecamera and subject is the point. If you use a 24mm lens but take the picture trim the same distance as you would with the 50mm lens, then you can crop in and get the _exact_ same picture as with the 50mm. But you will lose resolution obviously.

 

[whitedragon101]

Not entirely. The difference between 24 and 50mm is not only the wieder angle of view but mainly the relative distance and angle between the camera and the elements in the image (nose, eyes, ears, background). With a wider lens you need to get closer to the subject. By that, the angle which you are looking at e.g. the ears is different than if being farther away. You can’t correct that in post.
The other point is the size of nose, eyes, ears etc relative to each other. Let’s say you are extremely close a foot or so from the face, then the ears would be almost twice as far away than the nose, hence the size difference.

Bottom line is that th focal length of the lens is secondary but the distance ecamera and subject is the point. If you use a 24mm lens but take the picture trim the same distance as you would with the 50mm lens, then you can crop in and get the _exact_ same picture as with the 50mm. But you will lose resolution obviously.

Fantastic answer thanks

 

[Ben J.]

With a wider lens you need to get closer to the subject. By that, the angle which you are looking at e.g. the ears is different than if being farther away. You can’t correct that in post.

Yes you can. Like the Photo Booth app, most image editors have the ability to distort an image. Photo Booth does it for fun, apps like Photoshop have sophisticated lens correction tools, and can even let you select presets for specific lens models and sizes, and correct vignetting and many other things, but it's also very easy just to tell it to convert from 24mm to 50mm distortion. It's just maths. If Photos app doesn't have it, I'm sure you can find some free app that does.

Search for barrel distortion, lens correction.

I do this every once in a while in Lightroom or Photoshop. I just checked, and it seems Photos still doesn't do it.

 

[bunnspecial]

I keep meaning to set up an experiment with this.

The perspective correction tools in Photoshop/Lightroom are quite powerful, but remember too that they rely "squeezing" and "stretching" the pixels that are there so inevitably will either end up interpolating to keep the same size or cropping.

The experiment I'm envisioning is using my D850(45mp is close enough to 48mp) and a 24-70 zoom(which isn't as sharp as a good prime at those focal lengths, but is respectable) to use at the 24 and 50mm settings from one position, then moving the camera closer with the lens at 24mm.

Assuming I'm able to get this set up and get something to work with, I think this should tell if shooting at a "normal" 50mm distance and cropping a 24mm image down to a 50mm FOV will ultimately be better(with enough resolution) than attempting post processing perspective adjustment. I could see either result happening, which is why I want to experiment and find out.

 

[coolguy4747]

it will be extremely difficult to correct the perspective for both the person and the background, as there will be missing background information that you'll have to figure out what to do with, plus all the manipulated pixels will be battered around so badly it all won't look that great by the end.

 

[Ben J.]

it will be extremely difficult to correct the perspective for both the person and the background, as there will be missing background information that you'll have to figure out what to do with, plus all the manipulated pixels will be battered around so badly it all won't look that great by the end.

Nonsense. People do this all the time.

What is Lens Barrel Distortion?

Lens barrel distortion is a common optical aberration that affects the shape of a photo captured by a camera lens. Read the full guide here

www.iphotography.com

 

[coolguy4747]

Nonsense. People do this all the time.

What is Lens Barrel Distortion?

Lens barrel distortion is a common optical aberration that affects the shape of a photo captured by a camera lens. Read the full guide here

www.iphotography.com

If you have any examples close-up, wide-angle portraits made to look like they were shot at twice the distance I would love to see them. It's much easier when most objects are smaller in the frame, and not people.

 

[bunnspecial]

Perhaps someone else has some skills I don't, but I didn't have a lot of luck getting this to work.

Pardon my use of a stuffed animal instead of a person-hopefully it will work as a stand-in(and is about the size of a person's head. Minor exposure adjustments, and all photos did get Lightroom's correction profiles for this lens applied.

First of all, shot on a tripod, Nikon D850 w/24-70mm f/2.8E set to 50mm

Now lens zoomed out to 24mm, and result cropped to the same(aproximate) FOV as the 50mm image. I doubt you'll see a difference at web resolution. The difference is there in the full res originals(which are too big to upload here) but I honestly don't see more detail.

And finally, reframed so that the subject was about the same size in the frame(done by moving the tripod as much in a straight line forward as I could and not introducing side to side changes) with the lens zoomed to 24mm. I spent some time playing with it, but could not get the exaggerated perspective to go away(i.e. the size of the feet relative to the face) as well as the extra included background. I did not go into Photoshop to see if I could do it-from what I remember the perspective tools are somewhat more powerful there than in Lightroom so I'll try it time permitting, but it's different.

I still think that when dealing with plenty of spare resolution, framing as if a longer lens and cropping is probably still the best choice. As said, the D850 is 45mp, which is not significantly different from 48mp. Wide open, I don't think this lens takes full advantage of all the resolution the sensor offers.

 

[bunnspecial]

Well, maybe I spoke a bit too quickly...it seems as though Photoshop has a tool to do just this. It's not perfect, although it might be better if I spent some time really learning to use it, but it does accomplish something. The tool is called "adaptive wide angle"