85 or 105 on a full frame

Consdering getting a lens for portrait stuff.....wanting to find out what others are using on their full frame rigs?

Is 85mm good enough, or am I better going with a 105mm prime lens?

My thinking is that the 85mm might nit be enough, without getting real close to the subject to fill the frame. But is the 105mm too much? I don't want to have to back out of the room....

Scott (thoughts please?) B

Heya,

It's all personal preference. There's no right or wrong answer here. You could use a 35mm. You could use a 14mm! Distance to subject is what effects distortion, and telephoto lenses put a lot of distance between you and the subject, and that's basically the only significant reason folk use telephoto lenses for portrait--the resulting distance. You will be hard pressed to see a significant difference between 85mm and 105mm. In terms of distance, we're talking a few inches different. That's all.

Sounds like you're doing this in a studio (back to a wall).

Why do you feel you need a prime? Why not just get a sharp zoom? If you're in a studio, you're likely not doing F1.4 shots.

You could use a 35mm... 50mm... really doesn't matter. What matters is what you want it to look like, your working distance, and other features you feel you need.

85mm is a classic focal length for portrait for a reason. It's a good working distance while keeping you at distance, not too close (distortion) and not so far away that you have no room to work.

Very best,

^^^yeah but the problem with using less than 85 is that unless you want to heavily crop and waste image area, you will get distortion shooting less than 1/2 body shots. :P

OP, imo 85 is the perfect focal length for portraits. a longer lens will certainly add its own benefits, like completely destroying a background at f4, but 85mm will do just fine. i use an 85and a 135 and the 135 is often too long for more than headshots.

SDB777 wrote in post #17892085
Consdering getting a lens for portrait stuff.....wanting to find out what others are using on their full frame rigs?

Back in the "olden days", I used a 105mm Nikkor on my Nikon F cameras for head-n-shoulder portraits. I didn't do that too often as I shot mostly outdoor stuff and motor racing but I never felt under-equipped with the 105.

Thanks....

Was curious to see if folks got to 'Hey! You're right up in my face here!' during shoots. I'd like to fill more of the full frame, and reduce the cropping.....so I think I'll have to jump on a 105mm

Scott (but then again....85's are sweet) B

you wont be in anyone's face with an 85, with a 135 you might be across the street :P

Would one choose differently depending on Sensor being Full or Crop ? Would I be right in assuming that the lens perspective distortion would be the same irrespective of the sensor ?

your field of view will be different on a FF or crop, thus changing how close you stand when composing the image, thus changing your perspective and distortion. if you put a 85mm on a 1.6 crop it will have the fov of a 135mm, you will have less distortion and a slightly different perspective, granted at these focal length you will undoubtedly not notice it, what you may notice more is the depth of field at wide apertures.

if you use compare a 85mm on a crop with a FF at similar apertures, on the crop you have to stand further away from your subject to get a similar composition than if using a FF, thus decreasing your DOF.

one of the big advantages of a larger sensor that is isnt talked about is greater control over the depth of field at a given focal length.

if someone loves shooting 85mm on a crop, if they move to FF they should look immediately at getting a 135. when i used to shoot a crop i found the 85mm often too tight, but its perfect now that i shoot FF and likewise i find the 135 to be often too tight.

birderman wrote in post #17892941
Would one choose differently depending on Sensor being Full or Crop ? Would I be right in assuming that the lens perspective distortion would be the same irrespective of the sensor ?

Distance is the only thing causing distortion.

Focal length influences your distance to subject.

Doesn't matter what the sensor size is in this context. Field of view being different on the two sensors with the same focal length, will have your distance different for the same composition, and that distance again is the distortion or lack thereof source.

Very best,

birderman wrote in post #17892941
Would one choose differently depending on Sensor being Full or Crop ? Would I be right in assuming that the lens perspective distortion would be the same irrespective of the sensor ?

As stated above, varying focal length has nothing to do with changes in perspective. Perspective is changed only by changing the distances between your camera (or eyes) and the various elements of the scene in front of you.

Please read our "sticky" (found in the General Photography Talk forum) tutorial titled Perspective Control in Images - Focal Length or Distance?.

I would personally say 85mm for its versatility. I previously only had the 100L well it come to tele's and had used it for some portraits of a friend which was indoor. I struggled half body shots and his house was huge (the shots were in his living room). The 85mm will work both indoors and outdoors which is why it made more sense to me than a 135mm.

85mm 1.8 on full frame puts me at 3-4 feet for a horizontally framed headshot that is tightly composed. Basically I find that would be right at minimum focus distance on the Canon 1.8, so 4-5 feet is more realistic to get the shoulders. It's still close IMO, but you are not invading their space.