cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

EOS R7 showing shutter speed in inches

LoveWeims
Enthusiast

Why in Fv when I think I can adjust everything (shutter, aperture, and ISO) is Tv showing me inches?

I don't equate inches with shutter speed.  Perhaps there is a cogent answer in the EOS R7 manual but if so, I haven't found it...

4 ACCEPTED SOLUTIONS

Tronhard
VIP
VIP

Could you be confusing the " which is actually seconds as in 35'36" (35min 35sec) as inches?  When the shutter speed can no longer be shown as 1/xxx it will be shown as parts of a second - 0.3" i.e. 3/10sec.

This is because shutter speeds are generally displayed in stops, aka Exposure Values (EV's), where each is a doubling of halving of the light.  Using this common unit allows us to accurately translate values of one of the three variables: ISO, S/speed, Aperture between them so we can keep an exposure constant, but change the compositional aspects of the image - such as changing the shutter speed by 1EV up, which means that one of the others will have to go down in exposure value by one EV.
In ISO those are ascending scale 100-200-400 etc., as the number goes up, the gain applied to the sensor (signal amplification, if you will) is doubled. 
In apertures each EV is represented by an increase or decrease by the square root of 2 (because it's calculated as focal length/aperture, where the area is a function of Pi x((D/2) squared).  So, to get a consistent doubling or halving of light,  it must be increased or decreased by 1.4, which is why apertures go up as: 1, 1.4, 2, 2.8, 4...etc.   Because the aperture is the denominator, an aperture is correctly expressed as a fraction: f/2, f/5.6, f/8 etc. which explains why, as the number gets larger, the actual aperture hole gets smaller.
With shutter speed, if we start at 1" (1 sec), the next EV value would be 1/2 but if the camera is using smaller values than 1EV (which is common), as it gets between 1 and 1/2sec, it will show the shutter speed in units of decimals of a second, thus 0.3".


cheers, TREVOR

The mark of good photographer is less what they hold in their hand, it's more what they hold in their head;
"All the variety, all the charm, all the beauty of life is made up of light and shadow", Leo Tolstoy;
"Skill in photography is acquired by practice and not by purchase" Percy W. Harris

View solution in original post

shadowsports
Legend
Legend

Greetings,

They aren't inches.  😄 

You'll want to spend some time reviewing your manual.  There are a couple things to consider.  

https://cam.start.canon/en/C005/manual/html/UG-04_Shooting-1_0090.html

First review the section on minimum shutter speed based on ISO.  

Also you need to understand the camera supports 3 shutter modes.  Electronic, Electronic (1st curtain) and Mechanical.

In addition, you can set the range of minimum and maximum ISO and Shutter in the Custom Function menus.  See C.Fn2 menu.

C.Fn2

Have a look.  🙂

EDIT- Sorry posting from my mobile device. Didn't see your and Trevor's replies.  

~Rick
Bay Area - CA


~R5 C (1.0.7.1) ~RF Trinity, ~RF 100 Macro, ~RF 100~400, ~RF 100~500, ~RF 200-800 +RF 1.4x TC, BG-R10, 430EX III-RT ~DxO PhotoLab Elite ~DaVinci Resolve ~ImageClass MF644Cdw/MF656Cdw ~Pixel 8 ~CarePaks Are Worth It

View solution in original post

Nope, 30" is 30 seconds.  3/10 second would be shown as 0.3" or 0"3.  30" is a very long exposure.  So, that would suggest you are shooting in very dim light, or using a very, very high f/stop value - such as f/22, which is both tiny and likely to cause loss of quality due to diffraction.


cheers, TREVOR

The mark of good photographer is less what they hold in their hand, it's more what they hold in their head;
"All the variety, all the charm, all the beauty of life is made up of light and shadow", Leo Tolstoy;
"Skill in photography is acquired by practice and not by purchase" Percy W. Harris

View solution in original post

Thank you for the links (the second is broken) and I will study the one as I had no idea that was part of my answer…and thankfully I now at least know those aren’t inches!😉

 

 

View solution in original post

7 REPLIES 7

Tronhard
VIP
VIP

Could you be confusing the " which is actually seconds as in 35'36" (35min 35sec) as inches?  When the shutter speed can no longer be shown as 1/xxx it will be shown as parts of a second - 0.3" i.e. 3/10sec.

This is because shutter speeds are generally displayed in stops, aka Exposure Values (EV's), where each is a doubling of halving of the light.  Using this common unit allows us to accurately translate values of one of the three variables: ISO, S/speed, Aperture between them so we can keep an exposure constant, but change the compositional aspects of the image - such as changing the shutter speed by 1EV up, which means that one of the others will have to go down in exposure value by one EV.
In ISO those are ascending scale 100-200-400 etc., as the number goes up, the gain applied to the sensor (signal amplification, if you will) is doubled. 
In apertures each EV is represented by an increase or decrease by the square root of 2 (because it's calculated as focal length/aperture, where the area is a function of Pi x((D/2) squared).  So, to get a consistent doubling or halving of light,  it must be increased or decreased by 1.4, which is why apertures go up as: 1, 1.4, 2, 2.8, 4...etc.   Because the aperture is the denominator, an aperture is correctly expressed as a fraction: f/2, f/5.6, f/8 etc. which explains why, as the number gets larger, the actual aperture hole gets smaller.
With shutter speed, if we start at 1" (1 sec), the next EV value would be 1/2 but if the camera is using smaller values than 1EV (which is common), as it gets between 1 and 1/2sec, it will show the shutter speed in units of decimals of a second, thus 0.3".


cheers, TREVOR

The mark of good photographer is less what they hold in their hand, it's more what they hold in their head;
"All the variety, all the charm, all the beauty of life is made up of light and shadow", Leo Tolstoy;
"Skill in photography is acquired by practice and not by purchase" Percy W. Harris

Well - as a matter of fact - yes.  So does 30” equate to 1/30?  I had set the aperture to f5.6 (the widest on the lens i was using)?  It was the fastest shutter speed i was allowed i guess in view of available light.  I left ISO on auto

Nope, 30" is 30 seconds.  3/10 second would be shown as 0.3" or 0"3.  30" is a very long exposure.  So, that would suggest you are shooting in very dim light, or using a very, very high f/stop value - such as f/22, which is both tiny and likely to cause loss of quality due to diffraction.


cheers, TREVOR

The mark of good photographer is less what they hold in their hand, it's more what they hold in their head;
"All the variety, all the charm, all the beauty of life is made up of light and shadow", Leo Tolstoy;
"Skill in photography is acquired by practice and not by purchase" Percy W. Harris

No my f stop was set at 5.6!  I am sure my poor camera is as confused as i am

shadowsports
Legend
Legend

Greetings,

They aren't inches.  😄 

You'll want to spend some time reviewing your manual.  There are a couple things to consider.  

https://cam.start.canon/en/C005/manual/html/UG-04_Shooting-1_0090.html

First review the section on minimum shutter speed based on ISO.  

Also you need to understand the camera supports 3 shutter modes.  Electronic, Electronic (1st curtain) and Mechanical.

In addition, you can set the range of minimum and maximum ISO and Shutter in the Custom Function menus.  See C.Fn2 menu.

C.Fn2

Have a look.  🙂

EDIT- Sorry posting from my mobile device. Didn't see your and Trevor's replies.  

~Rick
Bay Area - CA


~R5 C (1.0.7.1) ~RF Trinity, ~RF 100 Macro, ~RF 100~400, ~RF 100~500, ~RF 200-800 +RF 1.4x TC, BG-R10, 430EX III-RT ~DxO PhotoLab Elite ~DaVinci Resolve ~ImageClass MF644Cdw/MF656Cdw ~Pixel 8 ~CarePaks Are Worth It

Thank you for the links (the second is broken) and I will study the one as I had no idea that was part of my answer…and thankfully I now at least know those aren’t inches!😉

 

 

shadowsports
Legend
Legend

Link fixed. Thanks

~Rick
Bay Area - CA


~R5 C (1.0.7.1) ~RF Trinity, ~RF 100 Macro, ~RF 100~400, ~RF 100~500, ~RF 200-800 +RF 1.4x TC, BG-R10, 430EX III-RT ~DxO PhotoLab Elite ~DaVinci Resolve ~ImageClass MF644Cdw/MF656Cdw ~Pixel 8 ~CarePaks Are Worth It

Avatar
Announcements