Why get smaller than Full Frame Sensor? Only Cost?

photolife44

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I'm quite new to interchangeable lens cameras and have been looking at Mirrorless.

I really would like to use old manual 35mm lenes on the camera I get, so not having any crop factor on FF is a big advantage.

I have been looking at different sensor sizes, APS-C and m4/3, these cameras are slightly cheaper (compared to a used Sony A7 which is about $1000).

The main downsides for smaller sensors for me are:

- Low light sensitivity reduced
- Aperture of adapted 35mm lenses reduced (f/1.2 = f/2.4 m4/3) which makes them pointless to use.

So is the only advantage of smaller sensors the cost of genuine autofocus lenses?
 
I'm quite new to interchangeable lens cameras and have been looking at Mirrorless.

I really would like to use old manual 35mm lenes on the camera I get, so not having any crop factor on FF is a big advantage.

I have been looking at different sensor sizes, APS-C and m4/3, these cameras are slightly cheaper (compared to a used Sony A7 which is about $1000).

The main downsides for smaller sensors for me are:

- Low light sensitivity reduced
Not quite correct. Less light reaches the sensor so more noise.
- Aperture of adapted 35mm lenses reduced (f/1.2 = f/2.4 m4/3) which makes them pointless to use.
??????? What exactly makes them pointless to use? You can't get extremely short depth of field on M4/3 but the lenses are certainly very usable.
So is the only advantage of smaller sensors the cost of genuine autofocus lenses?
Lens costs, sizes and weight.

Compare, say, a zoom lens that go to 600mm on FF and its equivalent focal length on smaller sensors.

FF: https://www.dpreview.com/products/tamron/lenses/tamron_150-600_5-6p3_vc

APS-C: https://www.dpreview.com/products/tamron/lenses/tamron_100-400_4p6-6p3_di_vc_usd

M4/3: https://www.dpreview.com/products/olympus/lenses/oly_m_75-300_4p8-6p7_ii

Lens size and cost is the reason that I use M4/3.

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Chris R
 
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I'm quite new to interchangeable lens cameras and have been looking at Mirrorless.

I really would like to use old manual 35mm lenes on the camera I get, so not having any crop factor on FF is a big advantage.

I have been looking at different sensor sizes, APS-C and m4/3, these cameras are slightly cheaper (compared to a used Sony A7 which is about $1000).

The main downsides for smaller sensors for me are:

- Low light sensitivity reduced
- Aperture of adapted 35mm lenses reduced (f/1.2 = f/2.4 m4/3) which makes them pointless to use.

So is the only advantage of smaller sensors the cost of genuine autofocus lenses?
keep looking at mirrorless - and forget about that old manual film lens

yes, there's cost of the camera and lens, but also other things smaller size and weight and the wider focal length lens on mirrorless are much smaller and you can use all the DSLR lens on mirrorless (with adapter)

www.flickr.com/photos/mmirrorless
 
Lens cost difference is not that big once you start looking at Olympus "PRO" lenses and realise that Tamron and Sigma - two big producers of cheap and good lenses for other systems - have very little to offer for M4/3 users.
 
I'm quite new to interchangeable lens cameras and have been looking at Mirrorless.

I really would like to use old manual 35mm lenes on the camera I get, so not having any crop factor on FF is a big advantage.

I have been looking at different sensor sizes, APS-C and m4/3, these cameras are slightly cheaper (compared to a used Sony A7 which is about $1000).

The main downsides for smaller sensors for me are:

- Low light sensitivity reduced
- Aperture of adapted 35mm lenses reduced (f/1.2 = f/2.4 m4/3) which makes them pointless to use.

So is the only advantage of smaller sensors the cost of genuine autofocus lenses?
My two cents:

When I see the difficult-to-detect difference between the results of M43 and the full-frame D800e, the D800e is a disappointment.

The M43 bodies and lenses are lower in cost, physically smaller and lighter and for the incremental (emphasis on incremental) difference in IQ of the full-frame, the full-frame D800e was a waste of money.

The difference in use between my m43 and my D800e is over 100 to 1, respectively, and I own them both.
 
I shoot Pentax crop because of the more tidily sized cameras and the fact that Pentax doesn't offer one of my crucial focal lengths/fields of view on FF.

I shoot Fuji crop because of the incomparable combination of shooting experience, JPEG quality, and prime lens selection that Fuji offers.

I could afford a FF camera and the two or three prime lenses I would want to go with it (a 50 and an 85/90, plus a slightly longer macro), but there isn't a combination of camera and lenses I would find even slightly more interesting than my current motley collection of crop gear, so I ahve never bothered to "move up".
 
I'm quite new to interchangeable lens cameras and have been looking at Mirrorless.

I really would like to use old manual 35mm lenes on the camera I get, so not having any crop factor on FF is a big advantage.
Just be aware that those old film era lenses generally perform poorly on modern high resolution digital cameras. So unless you have some really interesting legacy glass that you want to use for its unique characteristics, there's little point to that exercise.

It's definitely fun shooting with such lenses, though (I do from time to time).
I have been looking at different sensor sizes, APS-C
You can use a focal reducer that will mostly get rid of the APS-C crop factor.
and m4/3,
Can also use a focal reducer, but that only drops it from 2 to 1.4, so not what you want.
these cameras are slightly cheaper (compared to a used Sony A7 which is about $1000).
The main downsides for smaller sensors for me are:

- Low light sensitivity reduced
- Aperture of adapted 35mm lenses reduced (f/1.2 = f/2.4 m4/3) which makes them pointless to use.
By that logic, medium format cameras are pointless to use as well.
So is the only advantage of smaller sensors the cost of genuine autofocus lenses?
In general, there is no cost advantage to smaller sensor cameras, especially if you compare the prices to DSLRs, which are the most cost effective. So if you want cheap, go for a Canon or Nikon DSLR.

But if you want the best image quality (which you don't seem to be after), be prepared to spend serious cash, regardless of the format.
 
So is the only advantage of smaller sensors the cost of genuine autofocus lenses?
I shoot APS-C. Yes, cost was a significant factor in deciding. As a non-pro the expense just could not be justified.

Other factors are the weight and bulk of FF cameras and lenses, impractical for travel whether by plane or wilderness backpacking.
 
I'm quite new to interchangeable lens cameras and have been looking at Mirrorless.
that's a good idea, it's an incredible learning platform, much better than trying to learn on a dslr.

check out the adapted lens forum: https://www.dpreview.com/forums/1065
I really would like to use old manual 35mm lenes on the camera I get, so not having any crop factor on FF is a big advantage.
yes, because you can get the full width of the lens.

when it comes to legacy primes, 28mm is the last sweet spot for width, 24mm is doable, and wider than that is usually marginal at best.

putting a 28mm lens on m4/3 gives you the same angle of view as a 56mm lens on a ff sensor, which is of course extremely restrictive.
I have been looking at different sensor sizes, APS-C and m4/3, these cameras are slightly cheaper (compared to a used Sony A7 which is about $1000).
here in the states, you can find ff sonys for less than that... i'd suggest starting out with an a7ii at least.
So is the only advantage of smaller sensors the cost of genuine autofocus lenses?
crop glass isn't always cheaper, and in fact the smaller the sensor the worse the r.o.i. is, in terms of p.q. and resolution... ff lenses have the widest and cheapest selection, by far, and with sony you can use any lens, by any manufacturer.

there are some bargains to be had with modern ff glass... the 40/2.8 canon ff lens, for example, will give you autofocus with a cheap adapter on sony, and it's basically native af on a canon crop mirrorless like the m5.

--
dan
 
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To your point about APS-C not being much cheaper than the cheapest used FF...

That A7 FF for $1000 has sensor and AF tech that is inferior to a $450 A6000 APS-C. If you want comparable tech to a $750 A6300, you’d be spending $2-3k on a FF camera. Can’t compare top of the line APS-C to first gen, entry level FF.
 
I'm quite new to interchangeable lens cameras and have been looking at Mirrorless.

I really would like to use old manual 35mm lenes on the camera I get, so not having any crop factor on FF is a big advantage.

I have been looking at different sensor sizes, APS-C and m4/3, these cameras are slightly cheaper (compared to a used Sony A7 which is about $1000).

The main downsides for smaller sensors for me are:

- Low light sensitivity reduced
Not really. The a7 was never a competitive high-ISO performer, even in its day, and modern tech has left it behind. A recent model APS, such as Nikon D7200 or a6300 can equal or surpass it, and even the MFT Panasonic G9 is only about 1/2 stop behind.
- Aperture of adapted 35mm lenses reduced (f/1.2 = f/2.4 m4/3) which makes them pointless to use.
How do you mean? Put a 50/1.2 on MFT and your result will be exactly as if you'd shot it on a 64-80MP 35mm-format camera and then cropped away the outer 75% of the image. IOW, you'll still get the same shallow DoF, but with a narrower FoV. The result of an adapted 50/1.2 on MFT will look like a 100/2.4 shot on a 16-20MP 35mm-format camera.
So is the only advantage of smaller sensors the cost of genuine autofocus lenses?
Lens size. And glass quality. And body size. And features. And silence. And more.

My MFT glass is generally sharper at the edges than my 35mm-format Canon glass from 10 years ago. There isn't a lot of old manual-focus glass out there that can perform as well as good designs of the past 5 years. Mind you, before digital I shot with Contax/Zeiss for 15 years, so I know good manual-focus glass.

Here's why I switched to MFT:

How to Get Small - Part Four - Why I Switched to Micro Four Thirds Cameras
 

can you qualify why you see no difference? No doubt the d800e does have issues
 
I'm quite new to interchangeable lens cameras and have been looking at Mirrorless.

I really would like to use old manual 35mm lenes on the camera I get, so not having any crop factor on FF is a big advantage.
drawbacks include this glass being inferior to modern glass and most likely dealing with manual focus. That said there is some ok legacy glass. You can build a kit for a low cost and experiment with different looks while you swap out the lenses as you see fit. It is a route that worked for me and others but may not work for you
I have been looking at different sensor sizes, APS-C and m4/3, these cameras are slightly cheaper (compared to a used Sony A7 which is about $1000).
the a7 can be purchased as an open box with the kit lens for a grand(900 open box) in the usa. Nothing about it is top of the line. The sensor is average and newer crop sensors can come close to it(then again they actually cost more money sometimes). Af is just ok. You can rule sports out
The main downsides for smaller sensors for me are:

- Low light sensitivity reduced
- Aperture of adapted 35mm lenses reduced (f/1.2 = f/2.4 m4/3) which makes them pointless to use.
other people have discussed this. "pointless" is a bit harsh
So is the only advantage of smaller sensors the cost of genuine autofocus lenses?
POSSIBLE advantages include reduced size, costs of af lenses, and then you need to evaluate body to body. You may be able to get cameras with better af systems, better burst shooting, IBIS, or other features that may be appealing to a user.

The a7 basically represents a good value if you can deal with it's limitations. Up to you. You never said what you like to shoot, what lenses you would prefer, or where you are coming from

good luck

one last note. Here is the sony a7 put against various models at medium iso. Play with this tool to your content. Change the settings and move the crop tool around the frame. The a7 isn't as good as current models but still looks pretty good against some crop sensors that retail higher

 
As Chris alluded to, the crop factor is a huge benefit if you shoot wildlife. The Canon 100-400 L zoom is equivalent to 100-400 on a FF body, but on an APS-C body like mine, it is equivalent to 160 - 640.

--
https://www.flickr.com/photos/greg79
"You can't be young forever, but you can always be immature" - Larry Andersen
 
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Look at this video, and you will probably learn something:
 
a f stop never changes, only the sensor size changes,

but lets get into why one would would want a no full frame sensor.

one is to get a bridge camera where you can get a large zoom range for low cost, easy carrying around.

2 is if you prefer a detailed background as it is easier to get this with a smaller sensor.

3 is less weight per glass object.

so when you compare a 50 mm f 1.4 c mount lens to a 50mm ff 1.4 lens you are going to need less glass and can have have a smaller size and less weight.

4 if you are doing basic street photography, you can use smaller bodies, smaller lenses and be less intrusive.
 
The main downsides for smaller sensors for me are:

- Low light sensitivity reduced
The opposite is actually true. Smaller sensors are often more sensitive than larger sensors. The A7 and A7II are less sensitive than most current smaller sensors. You will get worse low light performance with them.
- Aperture of adapted 35mm lenses reduced (f/1.2 = f/2.4 m4/3) which makes them pointless to use.
You are talking about lens equivalency to a lens on another format. A 25mm F1.2 on m4/3 acts like a 50mm F2.4 on full-frame. If you measure the apertures of those lenses they are the same size, which is why they are equivalent.

A 50mm F1.2 lens adapted to a m4/3 camera doesn't become a F2.4 lens. It is still F1.2. The aperture is still twice the size of the 25mm F1.2 lens.
So is the only advantage of smaller sensors the cost of genuine autofocus lenses?
No, the only advantage is a smaller, cheaper sensor. Lens size has almost nothing to do with sensor size and everything to do with aperture size and focal length. A smaller sensor does require proportionally shorter focal lengths which sometimes allows shorter lenses.

Full-frame lenses are often cheaper, smaller, and lighter than equivalent smaller format lenses. It is dillemma. Invest in a larger silicon chip that has worse sensitivity just to use some cheaper, smaller lenses. Or invest in a cheaper, more sensitive small piece of silicon that requires more expensive, larger lenses.

APS-C is definitely the bang-for-buck trade-off.

I could see getting an A7R to use some film lenses with a not too out-of-date sensor. Instead I bought a $150 focal reducer.
 
The main downsides for smaller sensors for me are:

- Low light sensitivity reduced
The opposite is actually true. Smaller sensors are often more sensitive than larger sensors. The A7 and A7II are less sensitive than most current smaller sensors. You will get worse low light performance with them.
a picture is worth a thousand words


there is plenty of noise there for sure but it still cleans up well and retains a decent amount of detail. Comparing the more expensive a6500 shows little difference. Comparing the more expensive em1ii the a7 is still ahead. I just don't see where this claim comes from

the a7 is LESS EXPENSIVE than the comparison models. I threw in an a7rii to show what the top models can do today
- Aperture of adapted 35mm lenses reduced (f/1.2 = f/2.4 m4/3) which makes them pointless to use.
You are talking about lens equivalency to a lens on another format. A 25mm F1.2 on m4/3 acts like a 50mm F2.4 on full-frame. If you measure the apertures of those lenses they are the same size, which is why they are equivalent.

A 50mm F1.2 lens adapted to a m4/3 camera doesn't become a F2.4 lens. It is still F1.2. The aperture is still twice the size of the 25mm F1.2 lens.
So is the only advantage of smaller sensors the cost of genuine autofocus lenses?
No, the only advantage is a smaller, cheaper sensor. Lens size has almost nothing to do with sensor size and everything to do with aperture size and focal length. A smaller sensor does require proportionally shorter focal lengths which sometimes allows shorter lenses.

Full-frame lenses are often cheaper, smaller, and lighter than equivalent smaller format lenses. It is dillemma. Invest in a larger silicon chip that has worse sensitivity just to use some cheaper, smaller lenses. Or invest in a cheaper, more sensitive small piece of silicon that requires more expensive, larger lenses.
i will agree that it is a complicated subject. Also depending on your priorities the sensor may not even be a high priority.
APS-C is definitely the bang-for-buck trade-off.
It all depends. A lot of APSC manufacturers have not prioritized apsc lenses. Fuji is an exception. Then there are also wild cards like the Pentax k1 if you can deal with the af system and limited lenses
I could see getting an A7R to use some film lenses with a not too out-of-date sensor.
a7r is another wildcard. It has a worse af system than the original a7 ,suffers from shutter shock* if you are trying to maximize the potential of the sensor, and it is one of the last cameras I would throw cheap glass onto. If it were the same price as an a7 I would have less reservations
Instead I bought a $150 focal reducer.
 

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