I'm asking this in relation to the 50 1.8 vs 85 1.8 but I suspect it's the same for other pairs of lenses with the same aperture settings. Some say for starters get the 35mm and step in or crop to assimilate a 50mm. So Is cropping a 50mm portrait to the same FOV as the 85mm (given all settings are equal) a fair compromise or should you just get the longer lens? Does the 50mm have facial distortion characteristics like the 35mm, enlarged noses and such? Or does it have flattening and compression characteristics like the 85mm? If it all comes down to a similar image from both except the 50mm would be a half body and the 85 would be head and shoulders then buying the 50mm and saving $400 would a deal right? This can only be compared by people that own both (or all 3) or have tried them, or have excellent photography/composition knowledge because trying different zoom focal lengths at say 3.5-5.6 is not the same as having 3 different primes shot at 1.8.
Cropping vs longer lens
- Thread starter Deuce808
- Start date
on DX,
I think this will apply when I look into getting a ?-500+ zoom or stick with the 70-300 I already have.
More DOF then the 35 yes, but how about the 85? I was more concerned with any unflattering characteristics of the 50 if any compared to the 85. The 35 will widen features if you are too close, is thus the same on the 50? The 85? That's where having shot with the lens will tell the tale. I mean I much rather crop the 50 for head shots and save some cash but if the 85 is that much better then I will get it. It doesn't have to be $300-400 better but noticeably better will be a deciding factor.
"All else being equal" means camera-to-subject distance as well. Focal length will have no effect on the distortion you're referring to if you change FL but not the distance.
Horoscope Fish
Senior Member
The main difference I see between the 35mm, the 50mm and the 85mm focal lengths (yes, I own all three primes) is the amount of compression. For environmental, or full-body portraits, I could work with any of those three focal lengths if I had to. For head and shoulders portraits I would want nothing less than 85mm, for the extra working distance if nothing else, although my 70-200mm f/2.8 would be my first choice.
....
....
Focal length is just magnification of the view. Perspective is not affected by focal length, it is only dependent on the view from where the camera stands... and you do want to stand back a bit for portraits. If you have lots of excess pixels, cropping can work, but otherwise, it does discard a lot of pixels... that zooming in longer would not.
Last edited:
Thanks! So to sum up. The 3 lenses at 10ft to subject, all shot with same settings will bring no difference to the image except better bokeh/compression? Meaning I could crop a 35 with tack sharpness to a similar image to a 85 because the perspective will all be the same. If I wanted to move in to get a similar shot as a 85 without cropping then the 35 will throw out those distortions, but what about the 50? Does perspective affect it as it does the 35?
Horoscope Fish
Senior Member
I don't know that you could crop a 35mm image to match the field of view of an 85mm image taken at the same range AND have equal sharpness; you'd be tossing out an AWFUL lot of pixels. If I had to bet money on it, I'd say you would probably be able to get acceptable images cropping that much but I wouldn't go so far as to say you would get *equal* image quality out of both scenarios. While it might be feasible, I know I certainly wouldn't be comfortable cropping an image to that degree.
.....
The camera, if standing at the same place, can only see the same one view of the subject. We have to stand some other place to see a different view. But from wherever the camera is standing, that is what the view looks like. Meaning in a portrait, if the nose too near appears enlarged too much, it will look the same at any focal length, from that place. If standing at the same place, the relative size of a distant background object will appear the same relative size at any focal length (so I am also ruling out compression, it is just perspective). However, the subject size, and field of view, and the depth of field, certainly do vary with focal length, if still standing at that same place (these are magnification properties, not about perspective). But the view of any one smaller area does not change when simply enlarged. However, when you change where the camera stands, then certainly the view changes too.
We do see comparisons online showing portraits at different views of short and long lenses, but of course, they necessarily stand in very different places to make the subject be the same size in all. That is a perspective difference, but it is 100% caused by the view at that distance, not by the focal length. Focal length does cause us to move where the camera stands, but the view we see there depends on where we stand. Focal length is just a magnification of whatever view is seen (we like magnification too
)
It is a fairly obscure point. In practice, we necessarily do have to change where we stand with different lenses. The choice of the right lens does allow us to stand where we think is proper - or allows us to get a proper field of view from where we must stand. But if we don't move, then the view that we photograph is the same from that one place.
If you don't move where you stand, and if you crop the widest field of view (short lens) smaller to be the same as the narrow field of view (long lens), that corresponding area will see the same perspective. The really big difference is the cropped view has far few pixels remaining, the cropped view is a much smaller image size, requiring greater enlargement, not capable of the largest prints the way an uncropped image could have been. Using the longer lens crops the field of view too, but it still uses the full sensor size. But cropping it later discards many pixels, and we only have a smaller image remaining, so resolution is seriously reduced. If you already had an excess of pixels, more than you need, this may not be a big deal. If you didn't, it often is.
We always want to stand back 6 or 8 or 10 feet for a portrait (for proper perspective). This is true of a group shot with wide angle or a head shot with a telephoto, standing back a bit is important for proper perspective. But then if you crop out only one head in the group shot, its view will look the same as the longer head shot (if still the view from the same distance), except the cropped image has become a very small image, not capable of becoming the same good enlargement into the same large picture frame.
Saying, if the wider lenses has to stand too close to achieve size, that ruins the perspective of a portrait. Standing back and cropping can help that, but then again, it becomes a smaller image with less resolution. It is why we have different lenses, or zoom lenses.
We do see comparisons online showing portraits at different views of short and long lenses, but of course, they necessarily stand in very different places to make the subject be the same size in all. That is a perspective difference, but it is 100% caused by the view at that distance, not by the focal length. Focal length does cause us to move where the camera stands, but the view we see there depends on where we stand. Focal length is just a magnification of whatever view is seen (we like magnification too
)It is a fairly obscure point. In practice, we necessarily do have to change where we stand with different lenses. The choice of the right lens does allow us to stand where we think is proper - or allows us to get a proper field of view from where we must stand. But if we don't move, then the view that we photograph is the same from that one place.
If you don't move where you stand, and if you crop the widest field of view (short lens) smaller to be the same as the narrow field of view (long lens), that corresponding area will see the same perspective. The really big difference is the cropped view has far few pixels remaining, the cropped view is a much smaller image size, requiring greater enlargement, not capable of the largest prints the way an uncropped image could have been. Using the longer lens crops the field of view too, but it still uses the full sensor size. But cropping it later discards many pixels, and we only have a smaller image remaining, so resolution is seriously reduced. If you already had an excess of pixels, more than you need, this may not be a big deal. If you didn't, it often is.
We always want to stand back 6 or 8 or 10 feet for a portrait (for proper perspective). This is true of a group shot with wide angle or a head shot with a telephoto, standing back a bit is important for proper perspective. But then if you crop out only one head in the group shot, its view will look the same as the longer head shot (if still the view from the same distance), except the cropped image has become a very small image, not capable of becoming the same good enlargement into the same large picture frame.
Saying, if the wider lenses has to stand too close to achieve size, that ruins the perspective of a portrait. Standing back and cropping can help that, but then again, it becomes a smaller image with less resolution. It is why we have different lenses, or zoom lenses.
Last edited:
Thanks for all the info. The last 2 post really clarified things. I can make do without the 50 and will get the 85. If I had the 50 I could probably make do without the 85 or the 35 and maybe get something wider. 35+85 or 24+50 would be a useable 1-2 punch for my tastes. This is just my opinion of the shots I take and the resolution I need. The info you all gave will help for future composition as well as future lens purchases too!
This is just a distraction, since a $400 budget won't be enough, but my own preference is a good zoom covering the same 35-85 mm (FX needs at least 120mm). Unless you just crave f/1.8 for some perverted reason.
I think f/1.8 results are always too poor, f/2.8 lenses are better. And prime lenses are not versatile, too limited in where we have to stand. But in particular, the depth of field of a f/2.8 telephoto can always blur a distant background better than a shorter f/1.8 can (focal length is also a big factor). Plus of course, the biggie is that then the camera position can actually choose the smaller portion of the more narrow background that will be seen behind the subject.
I think f/1.8 results are always too poor, f/2.8 lenses are better. And prime lenses are not versatile, too limited in where we have to stand. But in particular, the depth of field of a f/2.8 telephoto can always blur a distant background better than a shorter f/1.8 can (focal length is also a big factor). Plus of course, the biggie is that then the camera position can actually choose the smaller portion of the more narrow background that will be seen behind the subject.
Yes, the f/2.8 zoom quality can match the primes. But the longer 70-200 f/2.8 can blur the backgrounds better (but is pretty long for general work on DX). They are pricy, but are comparable to the price of a better body. I use the 70-200 for my portrait lens on a FX D800. And speaking of cropping, this is 100% crop, 120mm at 10 feet here, on a 36 megapixel D800 (click it for larger, but realize that full screen on a HD wide monitor is only 2 megapixels - this crop is only about 0.3 megapixels.) This is f/8, I am not a fan of f/1.8.
Last edited:
I was intending to wait a while for a new lens but I ended up finding a 85 1.8 for $380, it'll be here in a couple days. If all turns out well with the savings I might just pick up the 50 1.8 too! Actually that money may better be spent on a Thinktank Retrospective 40. Thanks for all the info.
Btw, which cruising YouTube I found a channel called weeklyimogen, while not exactly super technical she does make a good use of the 50 1.8 (cannon but same theory) if the 85 didn't roll around at that price I would've grabbed a new 50.
Btw, which cruising YouTube I found a channel called weeklyimogen, while not exactly super technical she does make a good use of the 50 1.8 (cannon but same theory) if the 85 didn't roll around at that price I would've grabbed a new 50.