Shutter speeds

A

Alan Baird

Suspended / Banned
Messages
21
Name
Alan
Edit My Images
Yes
Olympus E520 shutter speeds Moving from display for 1 second (1") to faster speeds,display then reads 1.3, 1.6,2.0 etc before returning to normal 1/4 1/8 1/15 etc. Can somebody explain what the decimal read outs represent:thinking:
 
I'm not familiar with Olympus... but are they speeds greater than 1 sec, rather than a fraction of a second ?
 
KC Leblanc said:
I'm not sure you're right there. 1.3" would be 1.3 second. 1.3 is 1/1.3 so about three quarters of a second.
Click to expand...

:nono:

OP said his display switches between fractions and decimals......the fractions are exactly that, fractions of 1 second. The decimals will start to show 1 second and slower.....1.3 will be 1.3 seconds (roughly 1 and a third seconds), which on my 40D shows as 1"3.....
 
Thanks for your response. I don't think we are quite there yet probably due to me not explaining fully. The display I get on the camera, if I look at it starting from quarter of a second which is displayed as 4 and start going down the scale to slower speeds, the display reads 4,3,2.5,2,1.6,1.3,1",2",1.3"1.6"2" and continues to 'bulb'. The bit that is confusing me is the settings between 3 (1/3rd) and 1" (1 second) Hope this explains it a bit better.
 
I imagine the series 4 , 3 , 2.5 , 1.6 , 1.3 , 1 = 1/4, 1/3, 2/5, 1/2, 1/6, 1/3, 1

EDIT: Scrap that, I'm confused...
EDIT2: Haha, just noticed how poor I am at maths.
 
Okay, so 4, 3, 2.5, 2, 1.6, 1.3, 1 = 1/4, 1/3, 1/2.5, 1/2, 1/1.6, 1/1.3, 1

Does that make sense?
 
This is driving me nuts! Bottom line is that I don't think it is really a big issue but I find it very frustrating not being able to translate the figures to something simple. I can see where you are coming from on your last message but I can't fathom out, for example, what 1/2.5 represents particularly when this and the other decimal figures appear prior to reaching one second which to my mind indicates that it is less than a second. I appreciate the time and effort that you are putting into this but don't knock yourself out or you will end up as nuts as me!:bang:

Thanks
 
The number prior to the 1 (which is 1 second) are fractions and mean 1/ the number. The numbers after, with the ", denote actual time (secs). Hence on your scale:

1/4 = 0.25 seconds

1/1.3 = 0.77 seconds

1.3" = 1.3 seconds

Hope that is what you are asking :)

Matt

EDIT: Just noticed this is an older thread...oops!
 
This is a bit rambling......

The shutter speeds are changed in fractional increments of a 'stop'.

A 'stop' is a havling or doubling of light depending on what side your coming from. (this term applys to Aperture aswell as ISO - for reference)

I generally have the exposure control set at 1/3rd increments, therefore when i turn the main dial to adjust the shutter, on the 3rd click i've moved 1-stop or in otherwords I am halving or doubling the light/exposure/shutter value.

My Canon 500D can be configured to operate at 1/3 or 1/2 stops (from the custom function menu) so just ensure your working at 1/3rds for this!!

To test it....pick 10 seconds on your shutter value..
adjust your exposure 3 clicks up - you should arrive at 20 seconds or 1stop up (or 3 x 1/3rd increments of a stop slower)
bring it back to 10secs adjust 3 clicks down - you should arrive at 5 secs or 1stop down (or 3 x 1/3rd increments of a stop faster)

You can see by using 10secs as an example, the doubling havling effect is mathematically easy to see.

Now test it anywhere in your shutter speed value ie. 1/60 (3clicks) down to 1/30 - 1/60 (3clicks) up to 1/125. - still doubles , still halves, still 1stop!

The Canon 500d shutter scale runs;
1/8, 1/6, 1/5, 1/4, 0"3, 0"4, 0"5, 0"6, 0"8, 1", 1"3, 1"6, 2"

I think the bit in bold is the confusing part, because suddenly there is a fraction to decimal conversion. I see those numbers as a percentage of a second.
0"3 = 30% (or 1/3apprx)
0"4= 40% (or 2/5)
0"5= 50% (or 1/2)
0"6= 60% (or 3/5)
0"8= 80% (or 4/5)
1" = 100% of 1 second

If you use 1/5 shutter speed and move 3 'clicks' to the right to land on 0"4 - you can see that doubles your value or increases by 1stop or maybe easier to see 1/4 becoming 0"5 or (1/2).

So if you know you are working in 1/3 increments, it may help you calculate the figure in your head if your screen display looks confusing!

Hope that helps



Andy
 
You must log in or register to reply here.
Back
Top