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Subject: Focus testing my TL120 tues - suggestions?
Date: 2012-08-20 03:57:50
From: Mark

Hi

I have a big wedding on sat and I want to be 100% confident on the focus so running tests.

Anyone have a favorite way to go about this?

I know where there is a red spotted table cloth and I'll bring along some small objects, a note pad and tape measure.

A friend is up for being a sample subject as well so I figure there's two shots of his head - wide open and down to f 8 / f11 with tape extended out to behind his head.

Shooting in the AM GMT.

Any preferred DOF online calculators that do print outs?

Cheers

Mark

Subject: Re: Focus testing my TL120 tues - suggestions?
Date: 2012-08-20 08:13:14
From: Bob Venezia

Hi Mark,

If you can prop the tape so it's visible and readable you won't need a model. You'd probably need a loupe to read what's in best focus. Just read the tape. The tape will need to be at a slight angle so it can be read.

Bob Venezia

Seattle, Washington USA

Sent from my iPhone

On Aug 20, 2012, at 2:57 AM, "Mark" <blackice@pavilion.co.uk> wrote:

Hi

I have a big wedding on sat and I want to be 100% confident on the focus so running tests.

Anyone have a favorite way to go about this?

I know where there is a red spotted table cloth and I'll bring along some small objects, a note pad and tape measure.

A friend is up for being a sample subject as well so I figure there's two shots of his head - wide open and down to f 8 / f11 with tape extended out to behind his head.

Shooting in the AM GMT.

Any preferred DOF online calculators that do print outs?

Cheers

Mark

Subject: Re: Focus testing my TL120 tues - suggestions?
Date: 2012-08-20 11:31:02
From: John Thurston

On 8/20/2012 1:57 AM, Mark wrote:

> Hi
>
> I have a big wedding on sat and I want to be 100% confident on the focus so running tests.

> Any preferred DOF online calculators that do print outs?

I use the applications at DOF Master (www.dofmaster.com)
He has an ipod application (among others) but I still like
my printed analog calculator.

John Thurston
Juneau, Alaska

Subject: Re: Focus testing my TL120 tues - suggestions?
Date: 2012-08-20 11:40:50
From: Brian Reynolds

Mark wrote:

>
> I have a big wedding on sat and I want to be 100% confident on the
> focus so running tests.
>
> Anyone have a favorite way to go about this?
>
> I know where there is a red spotted table cloth and I'll bring along
> some small objects, a note pad and tape measure.
>
> A friend is up for being a sample subject as well so I figure
> there's two shots of his head - wide open and down to f 8 / f11 with
> tape extended out to behind his head.
>
> Shooting in the AM GMT.

How are you going to judge focus? On film? Or with a ground glass at
the film plane?

One of the magazines had an interesting article a few years ago about
checking focus and DoF by using brand new US Dollar bills.

A target was built with the dollars at different distances, and
staggered left to right so that from the camera position you could see
the corner of each of the bills. You focus on the center bill and
take a picture. By examining the engraving on the film at high
magnification you could determine which bill was in focus, and if your
camera was focusing on the correct distance. From above the target
would look something like this.

--
--
--

^ camera

US bills were used because of the fine engraving. Some people have
used brand new playing cards, but I don't think the engraved detail
and printing is as good.

> Any preferred DOF online calculators that do print outs?

I like DOF Master <http://dofmaster.com/>. It's available on the web,
MS Windows, Palm OS, Android, and iOS.

--
Brian Reynolds | "It's just like flying a spaceship.
reynolds@panix.com | You push some buttons and see
http://www.panix.com/~reynolds/ | what happens." -- Zapp Brannigan
NAR# 54438 |

Subject: Re: Focus testing my TL120 tues - suggestions?
Date: 2012-08-20 14:11:41
From: JR

The standard focus test target in the industry is the Siemens Star Target http://en.wikipedia.org/wiki/Siemens_star

It is also called a back focus target, because it is often used for checking the back focus setting of lenses on video cameras. For depth of field purposes, I use a series of them, mounted on pedestals, at different measured distances.

JR
stereoscope3d@gmail.com

On Mon, Aug 20, 2012 at 10:40 AM, Brian Reynolds <mf3d@reynolds.users.panix.com> wrote:

Mark wrote:
>
> I have a big wedding on sat and I want to be 100% confident on the
> focus so running tests.
>
> Anyone have a favorite way to go about this?
>
> I know where there is a red spotted table cloth and I'll bring along
> some small objects, a note pad and tape measure.
>
> A friend is up for being a sample subject as well so I figure
> there's two shots of his head - wide open and down to f 8 / f11 with
> tape extended out to behind his head.
>
> Shooting in the AM GMT.

How are you going to judge focus? On film? Or with a ground glass at
the film plane?

One of the magazines had an interesting article a few years ago about
checking focus and DoF by using brand new US Dollar bills.

A target was built with the dollars at different distances, and
staggered left to right so that from the camera position you could see
the corner of each of the bills. You focus on the center bill and
take a picture. By examining the engraving on the film at high
magnification you could determine which bill was in focus, and if your
camera was focusing on the correct distance. From above the target
would look something like this.

--
--
--

^ camera

US bills were used because of the fine engraving. Some people have
used brand new playing cards, but I don't think the engraved detail
and printing is as good.

> Any preferred DOF online calculators that do print outs?

I like DOF Master <http://dofmaster.com/>. It's available on the web,
MS Windows, Palm OS, Android, and iOS.

--
Brian Reynolds | "It's just like flying a spaceship.
reynolds@panix.com | You push some buttons and see
http://www.panix.com/~reynolds/ | what happens." -- Zapp Brannigan
NAR# 54438 |

--

Subject: Re: Focus testing my TL120 tues - suggestions?
Date: 2012-08-20 21:17:13
From: Don Lopp

On 8/20/12 1:11 PM, JR wrote:

> The standard focus test target in the industry is the Siemens Star
> Target *http://en.wikipedia.org/wiki/Siemens_star
> *
> It is also called a back focus target, because it is often used for
> checking the back focus setting of lenses on video cameras. For depth
> of field purposes, I use a series of them, mounted on pedestals, at
> different measured distances.

I do not understand why anyone would suggest using the fuzzy halftone
image of the Siemens Star target, as presented by Wikipedia, to be used
as a focus test subject? I would consider Brians idea of using the
'sharply' engraved dollar bill target target as providing a far superior
test subject for checking focus. I doubt that Mark would have time to
purchase sharper copies of the Siemens Star Target, if available, and
Mark probably already has a few sharply engraved dollar bills, in his
possession.

I consider the suggestion by Bob Venezia of using an angled measuring
tape as being a more suitable focus test subject, than a fuzzy Siemens
Star Target

The best,

DON

Subject: Re: Focus testing my TL120 tues - suggestions?
Date: 2012-08-21 10:05:05
From: Mark

Hi

Shoot done now and pickup slides tomorrow. I did a couple of cu shots. One human with a tape measure running from behind his shoulder to camera. Focused on eyeglasses (nice contrasty)

The 2nd was a red and white doted table clothe with a pen tip in focus.

Plus a bunch of other variations without the tape measure in place.

M

--- In MF3D-group@yahoogroups.com, Brian Reynolds wrote:
>
> Mark wrote:
> >
> > I have a big wedding on sat and I want to be 100% confident on the
> > focus so running tests.
> >
> > Anyone have a favorite way to go about this?
> >
> > I know where there is a red spotted table cloth and I'll bring along
> > some small objects, a note pad and tape measure.
> >
> > A friend is up for being a sample subject as well so I figure
> > there's two shots of his head - wide open and down to f 8 / f11 with
> > tape extended out to behind his head.
> >
> > Shooting in the AM GMT.
>
> How are you going to judge focus? On film? Or with a ground glass at
> the film plane?
>
> One of the magazines had an interesting article a few years ago about
> checking focus and DoF by using brand new US Dollar bills.
>
> A target was built with the dollars at different distances, and
> staggered left to right so that from the camera position you could see
> the corner of each of the bills. You focus on the center bill and
> take a picture. By examining the engraving on the film at high
> magnification you could determine which bill was in focus, and if your
> camera was focusing on the correct distance. From above the target
> would look something like this.
>
> --
> --
> --
>
> ^ camera
>
> US bills were used because of the fine engraving. Some people have
> used brand new playing cards, but I don't think the engraved detail
> and printing is as good.
>
> > Any preferred DOF online calculators that do print outs?
>
> I like DOF Master <http://dofmaster.com/>. It's available on the web,
> MS Windows, Palm OS, Android, and iOS.
>
> --
> Brian Reynolds | "It's just like flying a spaceship.
> reynolds@... | You push some buttons and see
> http://www.panix.com/~reynolds/ | what happens." -- Zapp Brannigan
> NAR# 54438 |
>