What makes full frame so much better for landscapes and portraits?

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joescrivens

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I keep reading that full frame cameras are better for landscapes and portraits than a crop, just wondered if people could explain why this is so?

Fundamentally I assume the reason is that on a full frame you can get more of the scene in from where you are standing. But am I being really stupid by saying - couldn't you just step backwards a bit with your crop to get the same?

shoot me down please I would love to understand it.

how does it make portraits better?
 
For landscapes, by "stepping back" you alter the perspective and effectively flatten the scene....for the same framed shot

The other part of the equation is that FF sensors generally have more dynamic range.

Bob
 
ok, I can understand that. Particularly about the extra dynamic range. thanks for explaining

and portraits?
 
joescrivens said:
Fundamentally I assume the reason is that on a full frame you can get more of the scene in from where you are standing. But am I being really stupid by saying - couldn't you just step backwards a bit with your crop to get the same?
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OK, e.g. you want to take some photos of a mountain range that's say 2 miles away & you've got a 1.6x crop camera. Using the same focal length you are going to have to step backwards more than "a bit" to get the same image from edge to edge as with a FF.

& as previously mentioned FF sensors tend to have larger photosites than crop - it's a quality versus quantity thing.
 
heidfirst said:
OK, e.g. you want to take some photos of a mountain range that's say 2 miles away & you've got a 1.6x crop camera. Using the same focal length you are going to have to step backwards more than "a bit" to get the same image from edge to edge as with a FF.

& as previously mentioned FF sensors tend to have larger photosites than crop - it's a quality versus quantity thing.
Click to expand...

but I guess, i could just reduce the focal length instead of moving backwards no?

so if the shot was perfectly framed on a FF at 24mm, I could zoom out to 15mm and get the same shot?
 
Compare the right things here..

A FF sensor at 12mp against a crop sensor at 12mp. The FF sensor noise should be lower. This is only really relevant at higher ISO settings.

As for perspective, a 10mm lens on a crop sensor is about the same as a 15/16mm full frame lens. So either will work and give you the same perspective.

A FF image tends to have the edge because of the larger pixels on the sensor.
 
I would be interested to know any 'theory' behind this too.

It's funny, when I went from a compact to a DSLR, one of the first things I noticed was how DOF made portraits look great. Now i've had my camera for quite while (Canon 40D), and compared results to the full frame 5D. It's the same again - there's a certain extra quality to those images. But I can't quite put my finger on what it is. I'm sure it's not just pixel count.
 
Well to put it bluntly you get more of the 'shot' in a full frame camera as opposed to a crop.

A 14mm wide angle lens on a FF is what it says: 14mm - but on a crop that same lens is 22.4 so less of the picture is in there.

As for portraiture I'm not too sure - too close to the subject and you get a dome effect but the 85mm 1.2 is a beautiful lens (Canon). However, economy wise a 50mm 1.2 is cheaper and gives the same approximate focal length (on a crop) as the 85mm.
 
razor777 said:
Well to put it bluntly you get more of the 'shot' in a full frame camera as opposed to a crop.

A 14mm wide angle lens on a FF is what it says: 14mm - but on a crop that same lens is 22.4 so less of the picture is in there.

As for portraiture I'm not too sure - too close to the subject and you get a dome effect but the 85mm 1.2 is a beautiful lens (Canon). However, economy wise a 50mm 1.2 is cheaper and gives the same approximate focal length (on a crop) as the 85mm.
Click to expand...

economy and a 50/1.4L in the same sentence :D
 
Forbiddenbiker said:
Diffraction is lessened on a full frame against a crop at the same f number ... as it is the larger the format used. :thumbs:
Click to expand...

For the same pixel count. If pixel density is the same then the diffraction will be the same. A 5D2 will exhibit the same DLA as a 20D or 30D.

Bob
 
razor777 said:
Well to put it bluntly you get more of the 'shot' in a full frame camera as opposed to a crop.

A 14mm wide angle lens on a FF is what it says: 14mm - but on a crop that same lens is 22.4 so less of the picture is in there.

As for portraiture I'm not too sure - too close to the subject and you get a dome effect but the 85mm 1.2 is a beautiful lens (Canon). However, economy wise a 50mm 1.2 is cheaper and gives the same approximate focal length (on a crop) as the 85mm.
Click to expand...

right but if the shot was in frame at 24mm on a ff and I used a 1.6 crop at 15mm then i'd get the same shot no?
 
When we used to shoot film, a Medium Format (MF) versus a 35mm photo had an indefineable 'feel' that just made them so much nicer, for me it was the way colours gaduated, the way skin looked sharp but soft (see I said it was indefinable) and flattered the sitter. I have an old photo (film) of my wife taken on a Yashica TLR that was a copy of a Rollei, the lens was pin sharp but had that 1940's quality to it, my Canon AE-1 with 135 was regarded as the bees knees but the images just werent the same, the old Yashica print is still my favourite.

Its the same in my view between FF and crop, the crops just look 'harsher'.

I wish you lot would stop discussing FF against crop :)

Matt
 
joescrivens said:
right but if the shot was in frame at 24mm on a ff and I used a 1.6 crop at 15mm then i'd get the same shot no?
Click to expand...

Indeed but trying shooting at 12mm on a crop? Can't be done, vice versa crop excels at telephoto - FF can't match that when pixel density is taken into equation. :)
 
Full frame is sharper, has more dynamic range, less noise, and over a stop less depth of field. But unless you print fairly big, at least A4 or larger, you will be very hard pressed to see the difference except in terms of DoF.

It's not just about pixel count - full frame is about 2.5x larger than crop. Pixels are much bigger. Lenses don't have to work so hard. If you compare say a 7D frame with a 5D2, with roughly similar number of pixels, the 5D2 looks much better. The visual difference is much more than say the difference between a 40D and a 7D, even though the latter has 80% more pixels because they are so damn small.

The advantage for landscapes is obvious I think. For portraits, I would like to achieve shallower depth of field occasionally without resorting to very low f/numbers which really need an ND filter with studio flash. More practically, I often find I want to crop portraits quite heavily which pushes my crop format 40D right to the limit. For example, I try to shoot as tight as I can, obviously, but then when I review the pics (not that obvious at the time of shooting) I can see a better image if I crop in hard. Another situation that sometimes occurs is when shooting two kids at once, which is often unpredictable, and I find that I've got a really good shot of one of them that I want as a solo portrait. I find that I can only get a really good result out of such a huge crop if I make a smaller print than I would like. So being able to pull out just half the frame would be really handy sometimes.

Full frame has less reach though. Crop format wins with long telephotos for sure, if only because the equivalent field of view requires such absolutely huge lenses on full frame. A 500mm lens on a crop is just about manageable, whereas the equivalent 800mm lens on full frame is neither practical nor affordable. If you can do it though, quality must be just incredible.

I'm constantly reviewing full frame vs crop in my own mind. I elected to go crop, finally, about a year ago and I still think it's the right decision for me. A top end crop camera can do anything pretty well, and is cheaper and smaller/lighter (or at least the lenses are). Full frame however will just not do long lens birding anything like so well.

Hmm :thinking: That's got me thinking again. I go birding about four times a year... :eek:
 
HoppyUK said:
Full frame is sharper, has more dynamic range, less noise, and over a stop less depth of field. But unless you print fairly big, at least A4 or larger, you will be very hard pressed to see the difference except in terms of DoF.

It's not just about pixel count - full frame is about 2.5x larger than crop. Pixels are much bigger. Lenses don't have to work so hard. If you compare say a 7D frame with a 5D2, with roughly similar number of pixels, the 5D2 looks much better. The visual difference is much more than say the difference between a 40D and a 7D, even though the latter has 80% more pixels because they are so damn small.

The advantage for landscapes is obvious I think. For portraits, I would like to achieve shallower depth of field occasionally without resorting to very low f/numbers which really need an ND filter with studio flash. More practically, I often find I want to crop portraits quite heavily which pushes my crop format 40D right to the limit. For example, I try to shoot as tight as I can, obviously, but then when I review the pics (not that obvious at the time of shooting) I can see a better image if I crop in hard. Another situation that sometimes occurs is when shooting two kids at once, which is often unpredictable, and I find that I've got a really good shot of one of them that I want as a solo portrait. I find that I can only get a really good result out of such a huge crop if I make a smaller print than I would like. So being able to pull out just half the frame would be really handy sometimes.

Full frame has less reach though. Crop format wins with long telephotos for sure, if only because the equivalent field of view requires such absolutely huge lenses on full frame. A 500mm lens on a crop is just about manageable, whereas the equivalent 800mm lens on full frame is neither practical nor affordable. If you can do it though, quality must be just incredible.

I'm constantly reviewing full frame vs crop in my own mind. I elected to go crop, finally, about a year ago and I still think it's the right decision for me. A top end crop camera can do anything pretty well, and is cheaper and smaller/lighter (or at least the lenses are). Full frame however will just not do long lens birding anything like so well.

Hmm :thinking: That's got me thinking again. I go birding about four times a year... :eek:
Click to expand...

i always had the impression that FF cameras had the option of a crop sensor mode, where for one it would compensate for non FF lenses, and with this option would give you the 'reach' comparable to a crop sensor.

Also from what i've read, if you crop a FF image by the crop factor you will get the same image?

An attempt at answering my own question would be: If a crop sensor has the same pixels as the full frame, then if using the method i stated above the full frame will have a poorer resolution once cropped ?

yeh or nay ?
 
seventythree said:
i always had the impression that FF cameras had the option of a crop sensor mode, where for one it would compensate for non FF lenses, and with this option would give you the 'reach' comparable to a crop sensor.

Also from what i've read, if you crop a FF image by the crop factor you will get the same image?

An attempt at answering my own question would be: If a crop sensor has the same pixels as the full frame, then if using the method i stated above the full frame will have a poorer resolution once cropped ?

yeh or nay ?
Click to expand...

The crop factor is a linear measurement, ie 1.6x for Canon. The actual sensor area is 2.6x larger with full frame. So if you crop say a 5D2 down to the same area dimesnions, its 21mp are reduced to 8mp - roughly the same as the 40D's 10mp.

In that sense you could argue that a 5D2 is 'dual mode' equivalent to a 40D but obviously has only half the number of pixels as a 7D's 18mp.

However, if you compare a 7D's 18mp with the 5D2's roughly equal 21mp, the 5D2 always comes out looking much better because its pixels are more than twice as big. If nothing else, it doesn't work its lenses nearly so hard and they are producing much higher image contrast at the relatively lower resolution level.

Basically, the number of pixels is a bit misleading, very misleading actually - it is just one factor in the imaging chain. You can't just divide and multiply arithmetically because every aspect of the process has its own MTF characteristics and they all cascade together to produce a final output - they are all actually analogue devices, including the sensor.

For example, the original 5D has 8mp* but it will blitz a 40D with 10mp on every aspect of image quality - sharpness, noise, contrast, everything - because its pixels are twice the size, it's gathering loads more photons and the lens is working at lower resolution and therefore much higher up the contrast scale. As resolution goes up, contrast goes down - basic optical truth - which goes most of the way to explaining why a compact's tiny sensor with maybe 14mp can't hold a candle to a full frame camera with a fraction of that number of pixels.

* Edit: correction, 5D has 12.8mp. Apologies, but if it only had 8mp the point would still be the same!
 
The original 5D is actually 12mp, not 8mp.

I've actually got quite used to APS-C and I think that the smaller format does have some advantages. There's adequate scope for DoF control for me, I can avoid the smaller apertures that FF would require to give the same DoF for landscape and I can get a width that I'm happy with with my Sigma 12-24mm With the slightly wider apertures I'm able to use with APS-C I can also use a slightly faster shutter speed and there's less chance of sensor contamination appearing on shots because I'm more likely to be using a relatively wide aperture. I'm paranoid about contamination so any evidence leads to an immediate clean.
 
david1701 said:
economy and a 50/1.4L in the same sentence :D
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that sounds really stupid I meant to say 50/1.2L which is really expensive, oh dear :(

seventythree said:
i always had the impression that FF cameras had the option of a crop sensor mode, where for one it would compensate for non FF lenses, and with this option would give you the 'reach' comparable to a crop sensor.

Also from what i've read, if you crop a FF image by the crop factor you will get the same image?

An attempt at answering my own question would be: If a crop sensor has the same pixels as the full frame, then if using the method i stated above the full frame will have a poorer resolution once cropped ?

yeh or nay ?
Click to expand...

afaik not, on canon at least the mirror can hit the back of the lens as EF-S lenses sit back further, the mount is also designed so they won't go on FF bodies
 
David1701:

Tis ok I knew what you meant - it's still cheaper than a 85mm 1.2 though hence economy ;)

seventythree:

You are basically correct saying that a FF cropped picture would have less density than an equivalent picture from a crop camera as it needs to lose a fair few amount of pixels to 'emulate' the crop. It can't magically move all the pixels into a crop equivalent square on the sensor. :)
 
My understanding is that the DOF is much shallower on a FF camera than a crop, meaning that portrait shots where bokeh is heavily used will be easier to acheive.
 
To answer the OP's question... nothing in the real world of not counting MTF lines & assuming we don't shoot too many landscapes at higher ISOs - they are just a bit different

How you use them will make far more difference to any shot than will simply FF or DX (Nikon's crop name)

:D

DD
 
DiddyDave said:
To answer the OP's question... nothing in the real world of not counting MTF lines & assuming we don't shoot too many landscapes at higher ISOs - they are just a bit different

How you use them will make far more difference to any shot than will simply FF or DX (Nikon's crop name)
:D

DD
Click to expand...

You always talk complete sense Dave. And I have to agree with you.

But after posted my earlier reply here, I realised that for the way that I do most of the things that I do, full frame is the better choice.

I emailed Kerso for a price on a 5DII and a set of three lenses and he came back (within six minutes!) with a mega deal.

My 40D and lenses will be up for sale this weekend, and the 7D I've been promising myself is not going to happen :D
 
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