How to accurately measure the F-stop opening ?

GeorgesGiralt

Member

Joined

Sep 16, 2004

Messages

523

Location

Toulouse, Fr

Format

Large Format

• Aug 2, 2007

• #1

Hi !
I own a Symmar 210/370 mm f:5.6/F:12. I had it on a Compur Electronic size 3.
This shutter is too big for my MPP Folding.
I have a Compur Electronic size 1 for it.
I have to adjust the iris opening to fit the 210 mm.
I know I've to measure from the front of the lens, lenses in place.
But how in order to be precise ?

 

Ole

Moderator

Moderator

Joined

Sep 9, 2002

Messages

9,245

Location

Bergen, Norway

Format

Large Format

• Aug 2, 2007

• #2

The cells will be the same, so will the cell spacing. So if you measure the physical opening of the aperture in the old and new shutters without the lens cells in place, they must be the same at the same f-stop!

 

epatsellis

Member

Joined

Jan 1, 2006

Messages

928

Format

Multi Format

• Aug 5, 2007

• #3

more importantly, any chance of you getting rid of your unwanted shutter?


erie

 

OP

OP

GeorgesGiralt

Member

Joined

Sep 16, 2004

Messages

523

Location

Toulouse, Fr

Format

Large Format

• Aug 6, 2007

• #4

epatsellis said:

more importantly, any chance of you getting rid of your unwanted shutter?


erie

Click to expand...

Humm ! No!
I like the Compur Electronic.
Currently the size 3 is at the repair shop because it works ok if you arm it in normal position. If when you arm it it is pointing down, when firing it, you will only get 1/250 speed, whatever position you fire it !
Last but not least, I've recently bought a Sinar Norma, so I'll be able to use the Size 3 more easily !