How to simply calculate CL vocal lengths on SL cameras?

[lct]

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9 minutes ago, ravinj said:

Alternatively, skip all other cameras and lenses - just use the Leica Q2 and you are assured that is a 28mm lens with a 28 mm "Fov" or "AoV". Always. All the time, crop function not withstanding

 

Not at all . When you use your Q2 in crop mode, the camera "crops" the sensor. Same for our colleague's SL2 above. Then FoV and DoF depend on that cropped part only. 

[ravinj]

How important is it to remember all this with EVF/live-view? 

[ravinj]

Just now, lct said:

Not at all . When you use your Q2 in crop mode, the camera "crops" the sensor. Same for our colleague's SL2 above. Then FoV and DoF depend on that cropped part only. 

But it still shows the full 28mm view with the crop overlay

[lct]

1 minute ago, ravinj said:

But it still shows the full 28mm view with the crop overlay

It's the shot that counts. If you shoot at say 50mm the camera uses only a cropped part of the sensor. There is no free lunch . 

[jaapv]

4 hours ago, Robert E said:

OK guys, then answer this question:  If Leica manufactures a lens made for the APS-C cameras (TL & CL) and they label it "55-135"mm: then what is it on the camera?

Is it a 55-135 or is it a "82-202" mm lens? Forget the FOV or AOV confusing stuff, stick to the mm's. There must be a reason it's labeled 55-135 and NOT 82-202, right?

This formula everyone seems to apply to an APS-C sensor camera of multiplying by 1.4 or 1.5x should not even come into play when the manufacturer labels the lens a specific MM in length.  It should only apply if you put a non-APS-C lens on the camera; IE: put a Leica VE 24-90 zoom on a CL camera. It's no longer a 24-90 because that is it's designation on a SL.

😃

 

The focal length is a property of the lens and not of the camera and will always remain the same (at infinity).

[ravinj]

13 minutes ago, lct said:

It's the shot that counts. If you shoot at say 50mm the camera uses only a cropped part of the sensor. There is no free lunch . 

Not for Q2. You can shoot at 75mm "crop" it will still capture the 28mm frame. All it does is to add metadata so what when imported in LR, the crop is applied by default. However, just click the crop overlay to see the 28mm frame. 

In other words - Q2 does not use "cropped" part of the sensor and there is free lunch after all; you can have your cake and eat it too with the Q2 (it is weather and cake proof). That's why you pay big bucks for Leica.

Edited April 3, 2021 by ravinj

[lct]

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Just now, ravinj said:

Not for Q2. You can shoot at 75mm "crop" it will still capture the 28mm frame. All it does is to add metadata so what when imported in LR, the crop is applied by default. However, just click the crop overlay to see the 28mm frame. 

In other words - Q2 does not use "cropped" part of the sensor.

OK thanks but If it is not the camera itself it is something else that crops the pic. LR in your case right?

[lct]

24 minutes ago, ravinj said:

How important is it to remember all this with EVF/live-view? 

Depends on how well we can view FoV and DoF in the EVF or on the screen. 

[ravinj]

4 minutes ago, lct said:

OK thanks but If it is not the camera itself it is something else that crops the pic. LR in your case right?

Correct, camera (Q2 or Q) is not cropping - it just shows a crop overlay in the center of the frame showing how it would be if applying the crop. This is actually good "behavior" as the full frame is always there. I don't use this feature at all as I feel it is a gimmick. It also applies crop by default when importing in LR which can be confusing unless you remember it is a cropped image. I use LR.

All of this for DNGs. I don't know how JPGs are handled.  

[ravinj]

1 minute ago, lct said:

Depends on how well we can view FoV and DoF in the EVF or on the screen. 

EVF is far more accurate for FoV than remembering it. For DoF, same thing. At least for me. 

Likely these things are good to remember for film or cameras with no EVF/LCD. Last time I used film was in 1988.

[beewee]

This thread seems to have gone off the rails. Here’s the original question from the OP:

On 3/31/2021 at 10:19 AM, vielhilftviel said:

Is there a website or a simple calculation I can do to calculate for example what the 18-56 would be on full frame?

And a follow up clarification: 

On 3/31/2021 at 10:53 AM, vielhilftviel said:

Ok then my question ist how to I calculate the equivalent point of view?

And yes I do want to use CL lenses on full frame because they are tiny and it’s just for video so I don’t care about loosing megapixels it will still be 4K if that makes sense.

It’s clear the intent of the OP’s question is to understand how to determine the equivalent framing between APS-C lenses on a full frame camera.

 

To answer this, it’s as simple as taking your CL lens focal length markings and multiply by 1.5 and this gives you an idea of the framing you would get if you had a full frame SL lens with the converted focal length (i.e. the CL lens focal length multiplied by 1.5).

 

Put another way:

[Converted full frame equivalent focal length framing] = [CL lens focal length marking] x 1.5

 

A numerical example:

27 mm = 18 mm x 1.5

So an 18mm CL lens will give you the equivalent framing as a 27mm lens on a full frame camera such as the SL.

 

That is it. Let’s move on and if we want to discuss FoV, AoV, AVoV, EFoV, let’s make a new thread for that stuff.

[lct]

56 minutes ago, ravinj said:

EVF is far more accurate for FoV than remembering it. For DoF, same thing. At least for me. 

Likely these things are good to remember for film or cameras with no EVF/LCD. Last time I used film was in 1988.

Depends on how much one does zone focusing on digital. Also when focus peaking does not work well enough and/or the subject moves too much for nailing focus with the EVF. Now i agree that (good) EVFs can change the game from this standpoint. 

[ravinj]

12 minutes ago, beewee said:

This thread seems to have gone off the rails. Here’s the original question from the OP:

And a follow up clarification: 

It’s clear the intent of the OP’s question is to understand how to determine the equivalent framing between APS-C lenses on a full frame camera.

 

To answer this, it’s as simple as taking your CL lens focal length markings and multiply by 1.5 and this gives you an idea of the framing you would get if you had a full frame SL lens with the converted focal length (i.e. the CL lens focal length multiplied by 1.5).

 

Put another way:

[Converted full frame equivalent focal length framing] = [CL lens focal length marking] x 1.5

 

A numerical example:

27 mm = 18 mm x 1.5

So an 18mm CL lens will give you the equivalent framing as a 27mm lens on a full frame camera such as the SL.

 

That is it. Let’s move on and if we want to discuss FoV, AoV, AVoV, EFoV, let’s make a new thread for that stuff.

Feel free to move on. 

[jaapv]

1 hour ago, lct said:

OK thanks but If it is not the camera itself it is something else that crops the pic. LR in your case right?

The camera puts the cropping information into the DNG file. 

[Robert E]

I found this article very interesting from another website:

https://www.nikonians.org/forum/topic/464-14603-14603/d500-focal-length-with-fx-lens#14604

It backs up what Bernard C, jaapv and Lct say above. So I wonder, who started this theory "you must multiply by 1.5x" ? 

Repeat after me: A 55-135 is a 55-135... 😃 

 

[lct]

4 hours ago, Robert E said:

So I wonder, who started this theory "you must multiply by 1.5x" ?

Can't seem to read your article but it was just the practice of small sensor cameras for me. Began with the Digilux 1 in 2002 with a crop factor of 4.7x or something then. Good old times .

[jaapv]

On 4/3/2021 at 7:59 PM, ravinj said:

In other words - Q2 does not use "cropped" part of the sensor and there is free lunch after all; you can have your cake and eat it too with the Q2 (it is weather and cake proof). That's why you pay big bucks for Leica.

It is not such a big deal -the camera does nothing that you cannot do in postprocessing. The only useful thing it does is show the framing for a centered crop

[ravinj]

3 minutes ago, jaapv said:

It is not such a big deal -the camera does nothing that you cannot do in postprocessing. The only useful thing it does is show the framing for a centered crop

Agree. My remark was more lighthearted. As I said in of the responses - I never found the centered crop overlay useful - like you say, if needed one can crop in post-processing. In fact, I find it annoying since the LR shows the images cropped by default upon importing and you have uncrop them to see the full image. But then I don't use it, so it doesn't do any harm.