EF and EFS, FF, Crop camera

delta0014 wrote in post #17881372
No,
If you take a few steps back with the crop, you're still gonna fill the frame as you would with a full frame a few steps closer.

This is where I don't understand what the 134mm equivalent of a FF camera or does to the photo, doesn't that change something.

If you had a crop with a 85mm on it and a full frame with 135mm on it and stood in the same spot and took a picture of a model on a bed, they would have almost identical FOV. They would show the same thing in the frame.

Take a look at this:

https://www.slrlounge.​com …l-frame-sensor-tips-in-2/

If I'm taking an image with a full frame camera and crop camera from the same fixed position and the same lens, the crop camera will provide a tighter field of view- the image will be cropped to the ratio of the sensor size.

So the 35mm equivalent- you would see the same field of view with an 85mm lens on a crop camera, and a 134mm lens on a full frame camera, if the cameras were in the same spot.


from wikipedia article on crop factor: https://en.wikipedia.o​rg/wiki/Crop_factor

delta0014 wrote in post #17881391
If you had a crop with a 85mm on it and a full frame with 135mm on it and stood in the same spot and took a picture of a model on a bed, they would have almost identical FOV. They would show the same thing in the frame.

I think you cleared it up for me, lets see if I understand what the 134 mm equivalent on a crop is telling me. If you want to take the same picture with a FF camera then I will need to change cameras from my T3i to a FF camera with a 134mm lens. Is that right?

Yes,

If you want to take the same picture with your crop and a 85mm lens, you'll need a FF and a 135mm lens.

Now, it will affect the perspective and depth of field with the 2 different lenses, but the both pictures will show the same amount of model/bed on it.

delta0014 wrote in post #17881415
Yes,

If you want to take the same picture with your crop and a 85mm lens, you'll need a FF and a 135mm lens.

Now, it will affect the perspective and depth of field with the 2 different lenses, but the both pictures will show the same amount of model/bed on it.

No, your perspective will not change if all you change between the two shots is the focal length used. If you move around between shots, then yes, your perspective will change.

TeamSpeed wrote in post #17881448
No, your perspective will not change if all you change between the two shots is the focal length used. If you move around between shots, then yes, your perspective will change.

He's right, my bad.

if you've never used a FF or film camera, just don't bother thinking about crop factor, or any of the math involved...there's no benefit...look thru your lenses and determine where you want to stand/frame up...don't use an app

right now you have the 55-250mm, set it at 85mm, and walk around with it like that for a few days, see if it works for you, if it's too long, set your 18-55mm to 50mm, and walk around with that to see if that works better...

buy what works for you, not what people say works for them

delta0014 wrote in post #17881415
Yes,

If you want to take the same picture with your crop and a 85mm lens, you'll need a FF and a 135mm lens.

Now, it will affect the perspective and depth of field with the 2 different lenses, but the both pictures will show the same amount of model/bed on it.

Thank you very much delta0014
I know it has been explained to me a million times but I couldn't pull it out of all the advanced tech talk that went along with it, I thought that with my 50mm lens and the equivalent being 79mm my pictures would come out FF shot at 79mm.

Thank you
Don

Descriptions of your (Canon) lenses (particularly those that fit both FF and APS-C bodies) are always listed by lens manufacturers in the context of how they are used on a FF body!

• A 24mm lens is a 'very wide angle' lens for FF (24x36mm), but it is a '(not very) wide angle' for APS-C (15x22.5mm), and it is a 'normal' lens for 4/3 format (13x17.3mm)
  
• A 35mm lens is a 'moderate wide angle' lens for FF (24x36mm), but it is about 'normal' for APS-C (15x22.5mm), and it is a 'short telephoto' for 4/3 format (13x17.3mm)
  
• A 50mm lens is a 'normal' lens for FF (24x36mm), but it is a 'short tele, waist up portrait' for APS-C (15x22.5mm), and it is a 'short telephoto, head & shoulders portrait' for 4/3 format (13x17.3mm)
  
• A 85mm lens is a 'short tele, 'waist up portrait' lens for FF (24x36mm), but it is a 'moderate telephoto (and a bit too long for indoor portraits)' for APS-C (15x22.5mm), and it is a 'short telephoto, and used for so-called outdoor portraits (candids)' for 4/3 format (13x17.3mm)
  
• A 100mm lens is a 'classic portraiture head & shoulders' lens for FF (24x36mm), but it is a 'moderate telephoto, and acceptable for so-called outdoor portraits' for APS-C (15x22.5mm), and it is a 'long telephoto' for 4/3 format (13x17.3mm)
  

• FF camera with 50mm
  
• APS-C camera with 31mm
  
• 4/3 format (Olympus OM-D) with 25mm
  

I really appreciate all of you for replying to my post.
There is a bunch of valuable information here that I'm going to take to heart.
Thank you all
Don

There are many ways to look at the crop-FF differences, and IMO most of them are confusing and misleading.

Simply put, small cameras need small lenses and big cameras need big lenses.

As others have stated, you could use the same lens on a crop and back up. You could also stay in the same place and use a smaller model. I don't agree with these viewpoints. As an artist, first decide on the composition you want - this involves the framing and perspective (distance to the subject). Then decide on the gear you need to capture your concept.

Long ago in history, crop frame cameras were 35mm cameras with a sensor that was too small, resulting in cropping of the image. Nowadays those same crop frame sensors have evolved into a legitimate format of their own. There are plenty of excellent EF-S lenses whose images are not cropped.

So it is time to put the history behind us and just work with our cameras for what they are.

I totally agree with DreDaze. If you only have one format, get familiar with that gear and how the focal lengths work. Forget about crop factors and equivalent angles of view. It's not that that information is wrong, it's just superfluous. It doesn't matter what the equivalent focal length is in a format you don't have. So for the crop format, a "normal" focal length is about 30mm, wide angle is 18mm, a good portrait lens for studio use is 50mm, and so on.

Myself, I have only crop bodies. Many times I have considered adding a FF body to my gear. But FF gear is expensive, buky and heavy. And for the kind of photograhy I do, crop is usually the better choice. So for now, I will stick with crop only. Budget is not a consideration for me in this choice. For you, the choice might be different, but I would suggest going crop until you find it is limiting you. When that happens, if it happens, you would probably want to add FF gear and keep the crop gear alongside it (instead of replacing it).

DigitalDon wrote in post #17881478
Thank you very much delta0014
I know it has been explained to me a million times but I couldn't pull it out of all the advanced tech talk that went along with it, I thought that with my 50mm lens and the equivalent being 79mm my pictures would come out FF shot at 79mm.

Thank you
Don

Yes, you are correct in your thinking.

If you use a 50mm lens on a crop camera, the photo will be very similar to a 80mm lens on a FF if you stand in the same place. (50 × 1.6 = 80)

There will be some differences in the depth of field depending on the aperture used, but the framing and magnification of the two photos will be the same.

.

msowsun wrote in post #17881533
Yes, you are correct in your thinking.

If you use a 50mm lens on a crop camera, the photo will be very similar to a 80mm lens on a FF if you stand in the same place. (50 × 1.6 = 80)

There will be some differences in the depth of field depending on the aperture used, but the framing and magnification of the two photos will be the same.

.

I think the point was being made that he was confused and thought that the same 50mm lens used on both bodies, the FF would automatically shoot at the 79mm equivalent focal length, and that is not the case. The equivalency factor was confusing, but has been cleared up. At least that is how I read it.

best to describe crop vs full frame on a video:




if that doesnt help, then a much more in depth explaination