Exposure calculation

When you use a view camera for macro work you have long extention on the
bellows.
You then need to compensate for the lost light to calculate a proper
exposure.
Does somebody have an easy way to calculate the exposure compensation?

I am using a 6x9 Linhof and want to play with a 5.6/100 Componon-S.
I guess you don't compensate down to 1m? ......but from here and closer?


Max

"Max Perl" wrote

> When you use a view camera for macro work you have long extention on the
> bellows.
> You then need to compensate for the lost light to calculate a proper
> exposure.
> Does somebody have an easy way to calculate the exposure compensation?

Calumet Photo used to (still does?) sell an inexpensive (under $10)
"close-up calculator." It consists of a square about 1-1/2" on each side
(one face is black, the other white), and a "ruler" that you place on the
ground glass. You place the small square piece up against your subject. With
the "ruler" you measure the size of the square as its image appears on the
ground glass and you read directly in f/stops the amount of extra exposure
required.

"Howard Lester" <heylester@dakotacom.net> skrev i en meddelelse
news:nYqdnaeYm4VXz5vVnZ2dnUVZ_veinZ2d@dakotacomip...
> "Max Perl" wrote
>
>> When you use a view camera for macro work you have long extention on the
>> bellows.
>> You then need to compensate for the lost light to calculate a proper
>> exposure.
>> Does somebody have an easy way to calculate the exposure compensation?
>
> Calumet Photo used to (still does?) sell an inexpensive (under $10)
> "close-up calculator." It consists of a square about 1-1/2" on each side
> (one face is black, the other white), and a "ruler" that you place on the
> ground glass. You place the small square piece up against your subject.
> With the "ruler" you measure the size of the square as its image appears
> on the ground glass and you read directly in f/stops the amount of extra
> exposure required.
>

Then it must be this one?

http://www.calumetphoto.com/item/CC9201/

"Max Perl" wrote

> Then it must be this one?
>
> http://www.calumetphoto.com/item/CC9201/

That's it!

"Max Perl" <max_perl@post11.tele.dk> wrote

> Does somebody have an easy way to calculate the [bellows extension]
> exposure compensation?

http://www.salzgeber.at/disc/

--
Nicholas O. Lindan, Cleveland, Ohio
Darkroom Automation: F-Stop Timers, Enlarging Meters
http://www.darkroomautomation.com/index2.htm
n o lindan at ix dot netcom dot com

On Apr 17, 1:27 am, "Nicholas O. Lindan" <s...@sig.com> wrote:
> "Max Perl" <max_p...@post11.tele.dk> wrote
>
> > Does somebody have an easy way to calculate the [bellows extension]
> > exposure compensation?
>
> http://www.salzgeber.at/disc/
>
> --
> Nicholas O. Lindan, Cleveland, Ohio
> Darkroom Automation: F-Stop Timers, Enlarging Metershttp://www.darkroomaut=
omation.com/index2.htm
> n o lindan at ix dot netcom dot com

Note that this covers up to full size copying. In principle, it is
probably possible to make good pictures at even more magnification
with a Componon-S. It would be pretty easy to extend the ruler
calibrations beyond full size. If you did, considering that you are
using a 6x9 camera, you might also want to start with the image of the
ruler and disk scaled to be comparable with or a little smaller than
the item being photographed.

"Nicholas O. Lindan" <see@sig.com> skrev i en meddelelse
news:1M-dnT92yKyo4JvVnZ2dnUVZ_judnZ2d@earthlink.com...
> "Max Perl" <max_perl@post11.tele.dk> wrote
>
>> Does somebody have an easy way to calculate the [bellows extension]
>> exposure compensation?
>
> http://www.salzgeber.at/disc/
>
> --
> Nicholas O. Lindan, Cleveland, Ohio
> Darkroom Automation: F-Stop Timers, Enlarging Meters
> http://www.darkroomautomation.com/index2.htm
> n o lindan at ix dot netcom dot com
>

Thank you!
I will try out the formular!

In article <4806409e$0$2101$edfadb0f@dtext02.news.tele.dk>,
"Max Perl" <max_perl@post11.tele.dk> wrote:

> When you use a view camera for macro work you have long extention on the
> bellows.
> You then need to compensate for the lost light to calculate a proper
> exposure.
> Does somebody have an easy way to calculate the exposure compensation?
>
> I am using a 6x9 Linhof and want to play with a 5.6/100 Componon-S.
> I guess you don't compensate down to 1m? ......but from here and closer?
>
>
> Max

A held calculator with this formula and then you can make your own
"dummy stick"


Indicated F/stop (Use a light meter) * Bellows Extension (Use a ruler)
____________________________________
Focal Length (Of the lens)


= Effective F/stop.

--
Reality is a picture perfected and never looking back.

"____" <internetphobic@deletedmail.com> skrev i en meddelelse
news:internetphobic-95D4CE.22431316042008@newsgroups.comcast.net...
> In article <4806409e$0$2101$edfadb0f@dtext02.news.tele.dk>,
> "Max Perl" <max_perl@post11.tele.dk> wrote:
>
>> When you use a view camera for macro work you have long extention on the
>> bellows.
>> You then need to compensate for the lost light to calculate a proper
>> exposure.
>> Does somebody have an easy way to calculate the exposure compensation?
>>
>> I am using a 6x9 Linhof and want to play with a 5.6/100 Componon-S.
>> I guess you don't compensate down to 1m? ......but from here and
>> closer?
>>
>>
>> Max
>
> A held calculator with this formula and then you can make your own
> "dummy stick"
>
>
> Indicated F/stop (Use a light meter) * Bellows Extension (Use a ruler)
> ____________________________________
> Focal Length (Of the lens)
>
>
> = Effective F/stop.
>
> --
> Reality is a picture perfected and never looking back.

Thank you!
I will try this!

Max Perl wrote:
> When you use a view camera for macro work you have long extention on the
> bellows. You then need to compensate for the lost light to calculate a
> proper exposure. Does somebody have an easy way to calculate the
> exposure compensation?

> I am using a 6x9 Linhof and want to play with a 5.6/100 Componon-S. I
> guess you don't compensate down to 1m? ... but from here and closer?

Would I be right in the belief that this question, and the solutions to it,
would be applicable to formats other than "large",
should one care to do such a thing?

(I do extremely little (haha) macro work, and my largest camera is a 645,
and while that and my old 35mm are pretty clunky, they still are advanced
w/r/t many large-format camera, correct? And, of course, my DSLR does
everything but procreate. So I doubt I will *need* to know this.
But it would be nice to know if it applies, and, if so, how to do it.)

I am surprised that no one has responded, yet. I'll be the duffer.

With a flash, a doubling of the distance from flash to subject is a 4 fold
reduction in illumination that's 2 stops. So in the same vein a doubling of
the bellows extension from say 150mm to 300mm would necessitate a 2 stop
increase or 4 fold increase of light requirement getting to the film..
Therefore a partial extension say 1/2 way would be 1 stop increase and so
on. Rough as guts but it is quick and gets you in the ball park (where ever
that is) to the nearest 1/2 stop. This does require one to mark by big fat
texta or neat biro on tape or mearly tape measure the increase in bellows
extension.

If you are new to macro, keep watch on the lighting so that the lens is not
so close to the product that it casts it's own shadow.



"MangroveRoot" <zcukpkn02@sneakemail.com> wrote in message
news:KC32k.2583$Yw1.410@trndny02...
> Max Perl wrote:
> > When you use a view camera for macro work you have long extention on the
> > bellows. You then need to compensate for the lost light to calculate a
> > proper exposure. Does somebody have an easy way to calculate the
> > exposure compensation?
>
> > I am using a 6x9 Linhof and want to play with a 5.6/100 Componon-S. I
> > guess you don't compensate down to 1m? ... but from here and closer?
>
> Would I be right in the belief that this question, and the solutions to
> it,
> would be applicable to formats other than "large",
> should one care to do such a thing?
>
> (I do extremely little (haha) macro work, and my largest camera is a 645,
> and while that and my old 35mm are pretty clunky, they still are advanced
> w/r/t many large-format camera, correct? And, of course, my DSLR does
> everything but procreate. So I doubt I will *need* to know this.
> But it would be nice to know if it applies, and, if so, how to do it.)

"MangroveRoot" wrote

> Would I be right in the belief that this question, and the solutions to
> it,
> would be applicable to formats other than "large",
> should one care to do such a thing?

If the lenses you use for your 645 are attached directly to the body, and
especially if your 645 has a built in TTL meter, the answer is "no." If your
lens attaches via a bellows, and your 645 doesn't have TTL, then the answer
is "yes." The greater the extension of the lens from the body, the greater
the required exposure.

Howard Lester wrote:
> "MangroveRoot" wrote
>
>> Would I be right in the belief that this question, and the solutions to
>> it,
>> would be applicable to formats other than "large",
>> should one care to do such a thing?
>
> If the lenses you use for your 645 are attached directly to the body, and
> especially if your 645 has a built in TTL meter, the answer is "no." If your
> lens attaches via a bellows, and your 645 doesn't have TTL, then the answer
> is "yes." The greater the extension of the lens from the body, the greater
> the required exposure.

That would be a "no" on both counts.
I *do* have a set of metal extension tubes, but that's not the same thing.
I was just curious. Sometimes it's nice to know more than I think I'll need.

Thank you Howard and otzi; your answers were ... illuminating!

Amazing!
Having re-read this post in day time, I now see the question. Bum, My
continual problem with late night web gazing:(
Can I take back my inappropriate response. (blush,blush)


"MangroveRoot" <zcukpkn02@sneakemail.com> wrote in message
news:C323k.1208$Mu.42@trndny07...
> Howard Lester wrote:
>> "MangroveRoot" wrote
>>
>>> Would I be right in the belief that this question, and the solutions to
>>> it,
>>> would be applicable to formats other than "large",
>>> should one care to do such a thing?
>>
>> If the lenses you use for your 645 are attached directly to the body, and
>> especially if your 645 has a built in TTL meter, the answer is "no." If
>> your lens attaches via a bellows, and your 645 doesn't have TTL, then the
>> answer is "yes." The greater the extension of the lens from the body, the
>> greater the required exposure.
>
> That would be a "no" on both counts.
> I *do* have a set of metal extension tubes, but that's not the same thing.
> I was just curious. Sometimes it's nice to know more than I think I'll
> need.
>
> Thank you Howard and otzi; your answers were ... illuminating!

"MangroveRoot" wrote

>> If the lenses you use for your 645 are attached directly to the body, and
>> especially if your 645 has a built in TTL meter, the answer is "no." If
>> your lens attaches via a bellows, and your 645 doesn't have TTL, then the
>> answer is "yes." The greater the extension of the lens from the body, the
>> greater the required exposure.

> That would be a "no" on both counts.
> I *do* have a set of metal extension tubes, but that's not the same thing.
> I was just curious. Sometimes it's nice to know more than I think I'll
> need.

Oh yeah - extension tubes. I forgot about those things. ;-) Extension
tubes serve the same purpose as a bellows, so it IS effectively the same
thing: they/it push your lens further from the film plane than it would be
if mounted directly to the body. The greater the extension, the more you
have to compensate for light loss.