Going from full frame to APS-C

[wooferdog]

Advertisement (gone after registration)

Hi all , I’m using a borrowed CL so see if I like it.

 

On the SL my most used lens is the 50 and 35 , So if I understand the crop , the 50 becomes a 75 and the 35 a 52.

 

Is it that simple , or are there other issue I need to be aware of.

 

Thanks

[M11 for me]

That is correct. Crop is 1.5x

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[M11 for me]

Maybe to be precise: The focal length of the lens does not change of course when applied to one or another camera with different sensor. We should rather say the lend behaves as . . . 

[wda]

One other consideration is that of sensor size.But that is not significant for non-professional photography.

[ramarren]

Hi all , I’m using a borrowed CL so see if I like it.

 

On the SL my most used lens is the 50 and 35 , So if I understand the crop , the 50 becomes a 75 and the 35 a 52.

Is it that simple , or are there other issue I need to be aware of.

 

The smaller sensor affects effective field of view and depth of field. 

• Yes, you have the 1.5x crop factor for the smaller sensor size figured correctly to accommodate the change in field of view. If you want the same field of view choices you have on the SL with a 35 and 50 mm lens pair, you'll need a 23-24mm lens to pair with your 35mm for the CL.

   

• The depth of field you're used to at various f/number aperture settings will change on the CL by one stop. In other words, if you normally set f/5.6 to achieve a depth of field you like on the SL with a 35mm field of view, you'll need to set f/4 on the CL with a 24mm lens to achieve the same thing: 24mm to get the same field of view, f/4 to get the same depth of field. 

Edited August 20, 2018 by ramarren

[stephan_w]

it is that simple, beside what was described in the last post. And you will be surprised how good it is. IMHO the best camera Leica offers today :-)

 

No, serious, it has some shortcommings, especially compared with the SL, but they are on the ergonomic side only (weather sealing, finish, some buttons and controls)

[jaapv]

Advertisement (gone after registration)

It is indeed that simple. In daily practice, it does not matter one whit, as you create the image as you see it regardless of numbers.

When you happen to have a 50 mm equivalent on, it will be a 50 mm type image, if you have a 75 mm equivalent on, you'll move back a bit and have a 75 mm perspective and DOF. So what? can you tell me in advance which one will be better?

The EVF, which shows you exactly what you are getting, is helpful.

[M11 for me]

The smaller sensor affects effective field of view and depth of field. 

 

• Yes, you have the 1.5x crop factor for the smaller sensor size figured correctly to accommodate the change in field of view. If you want the same field of view choices you have on the SL with a 35 and 50 mm lens pair, you'll need a 23-24mm lens to pair with your 35mm for the CL.

   

• The depth of field you're used to at various f/number aperture settings will change on the CL by one stop. In other words, if you normally set f/5.6 to achieve a depth of field you like on the SL with a 35mm field of view, you'll need to set f/4 on the CL with a 24mm lens to achieve the same thing: 24mm to get the same field of view, f/4 to get the same depth of field. 

To give the whole equivalence picture: with crop 1.5 (APS-C) . . .

 

To make it easier to calculate, lets take MicroFourThirds (M4T) with Crop 2: Panasonic / Olympus / Leica cameras

 

- 35mm lens on FF equals 35/2 = 18mm on M4T

- Aperture on FF of e.g. f/4 equals 4/2 = f/2 on M4T

- ISO on FF of 800 equals 800/2square = 800/4 = 200 on M4T

 

This given the following settings result in the

same field of view

same depth of field

same noise level

same brightness

of 2 pictures taken either with FF or with M4T

 

FF: 35mm focal length lens

FF: f/4 aperture

FF: ISO 800

 

M4T: 18mm focal length lens

M4T: f/2 aperture

M4T: ISO 200

 

It has to be added that plus/minus the same sensor technology has to apply

[tritentrue]

It is indeed that simple. In daily practice, it does not matter one whit, as you create the image as you see it regardless of numbers.

 

So much debate over numbers probably wouldn't occur if people could grasp this.

 

Weather, weight, and intended subject matter all influence whether I choose the CL or M when heading out the door; minor differences in lens angle of view are seldom a factor.

[ramarren]

To give the whole equivalence picture: with crop 1.5 (APS-C) . . .

To make it easier to calculate, lets take MicroFourThirds (M4T) with Crop 2: Panasonic / Olympus / Leica cameras

- 35mm lens on FF equals 35/2 = 18mm on M4T

- Aperture on FF of e.g. f/4 equals 4/2 = f/2 on M4T

- ISO on FF of 800 equals 800/2square = 800/4 = 200 on M4T

This given the following settings result in the

same field of view

same depth of field

same noise level

same brightness

of 2 pictures taken either with FF or with M4T

FF: 35mm focal length lens

FF: f/4 aperture

FF: ISO 800

M4T: 18mm focal length lens

M4T: f/2 aperture

M4T: ISO 200

It has to be added that plus/minus the same sensor technology has to apply

  

 

I'm at a loss to understand how comparing Micro-FourThirds equivalences to Full Frame provides clarity for APS-C equivalences when the crop factor and frame proportions are so different.

 

So much debate over numbers probably wouldn't occur if people could grasp this.

 

Weather, weight, and intended subject matter all influence whether I choose the CL or M when heading out the door; minor differences in lens angle of view are seldom a factor.

While I agree in large part the lookin through the viewfinder with a mounted lens provides the best insight into what the CL does with a given lens, the numbers are useful, briefly, when you're first trying out the CL if you want to previsualize what to expect, and what lenses to try out, basing your efforts on what you might know from previous experience. For my use, understanding and previsualization comes easily when I determine what focal length is the "normal" for a given format, and then all the others become easy.

[tritentrue]

 While I agree in large part the lookin through the viewfinder with a mounted lens provides the best insight into what the CL does with a given lens, the numbers are useful, briefly, when you're first trying out the CL if you want to previsualize what to expect, and what lenses to try out, basing your efforts on what you might know from previous experience. For my use, understanding and previsualization comes easily when I determine what focal length is the "normal" for a given format, and then all the others become easy.

 

I don't understand why you appended that to a quote of what I wrote because it's not what I said and most definitely not something with which I concur.

[jaapv]

It is the dichotomy between regarding the taking of a photograph as a creative act or as a technical process. 

[Le Chef]

Much like a musician, technical mastery liberates creative expression. I would have to believe that the FoV of a particular lens mounted on a particular camera becomes a “known” leaving you to focus on creating the most expressive image you can within those characteristics.

[Jeff S]

Another point to consider when using SL lenses on the CL is that the edges are cropped and the image results from the central ‘sweet spot’ of the lens. Others, though, prefer edge effects that are revealed by the ‘uncropped’ field of view. The latter viewpoint was frequently discussed here when the M9 superseded the M8 and some were excited to get back to using their M lenses as they did with film Ms.

 

Jeff

[M11 for me]

I'm at a loss to understand how comparing Micro-FourThirds equivalences to Full Frame provides clarity for APS-C equivalences when the crop factor and frame proportions are so different.

 

I took M4T because it is simply easier to calculate with the multiplyer of 2 compared to 1.5. But with 1.5 it works respectively but as results you get fractions: The gain of 1 LV of FF over APS-C is then not so clear to show.

[ramarren]

I don't understand why you appended that to a quote of what I wrote because it's not what I said and most definitely not something with which I concur.

Well, It seemed to be that you were agreeing with jaapv about it in the first sentence of the quote. I was responding to that, should have edited out the latter portion of the quote.

[ramarren]

I took M4T because it is simply easier to calculate with the multiplyer of 2 compared to 1.5. But with 1.5 it works respectively but as results you get fractions: The gain of 1 LV of FF over APS-C is then not so clear to show.

I don't think it helps at all, frankly. And the f/number doesn't change 'brightness' at all based on format, that is, f/8 on FF is exactly the same as f/8 on APS-C (and mFT) ... What does change is effective DoF, not brightness.

 

In other words, the settings of 50mm focal length with f/8 on FF nets exactly the same field of view and brightness as 35mm focal length with f/8 on APS-C, presuming the same ISO and shutter speed setting for both. What is different is that the Depth of Field is one stop greater on the APS-C setup: it is as if you'd set the FF camera to f/11.

Edited August 25, 2018 by ramarren

[M11 for me]

I don't think it helps at all, frankly. And the f/number doesn't change 'brightness' at all based on format, that is, f/8 on FF is exactly the same as f/8 on APS-C (and mFT) ... What does change is effective DoF, not brightness.

 

In other words, the settings of 50mm focal length with f/8 on FF nets exactly the same field of view and brightness as 35mm focal length with f/8 on APS-C, presuming the same ISO and shutter speed setting for both. What is different is that the Depth of Field is one stop greater on the APS-C setup: it is as if you'd set the FF camera to f/11.

 

Thats all correct: And I wrote nothing that contradicts you:

 

I wrote about quivalence of:

 

same field of view

same depth of field

same noise level

same brightness

 

The TO was asking about behaviour of different sensor sizes. Thats how they behave.

Edited August 25, 2018 by Alex U.

[wooferdog]

 

 

In other words, the settings of 50mm focal length with f/8 on FF nets exactly the same field of view and brightness as 35mm focal length with f/8 on APS-C, presuming the same ISO and shutter speed setting for both. What is different is that the Depth of Field is one stop greater on the APS-C setup: it is as if you'd set the FF camera to f/11.

 

Thank you for that , exactly what I was looking for. So if I understand correctly , on the CL the 35 becomes a 50 (more or less) and f4 on the CL would be f5.6 on the SL ?

 

Thanks for all the comments

[Advertisement]

Hallo,

Look here: Leica L-Mount

[lct]

All other things equal, only significant difference between 50mm lenses on FF cameras and 35mm lenses on APS-C cameras is depth of field (DoF). Then f/5.6 on the SL remains f/5.6 of the CL as far as brightness is concerned. But to get approximately the same DoF, the usual rule of thumb suggests to choose f/4 on the CL.