On Tue, 23 Jan 2001, Bradley Small wrote:
> How long should the bellows be? I am assuming that the longer is for
> closeup and the shorter is for infinty and wide angle.
>
> How much movement is necessary? I assume at some point it is no longer
> useful. I assume each of these movements has a name.
>
> Left/right? Up/down? Rotation left/right? Rotation Up/Down?
>
> Should both the back and the lens have movements, or just the lens?
These are questions that only you can answer since they all depend on the
kind of photography you want to do?
One of the better pieces of advice I was given when I got interested in
these cameras was to decide on the lenses I wanted to use first and then
look for a camera to fit the lens. Very few if any view cameras can use
any possible lens out there. If you plan on only using a normal 150 mm
lens on this camera you probably don't need the bellows to be more than
twice this or 300 mm. With shorter lenses you can get by with less
bellows, and the minimum focusing distance becomes more critical. For
example, the camera I built using the View Camera plans can barely focus
my 135 mm lens, and then only after I modified the front focus a bit. It
can focus longer lenses fine. Naturally if you want to use long lenses
you'll need longer bellows.
If you are doing photography where extreme perspective control is either
not needed or noticeable (portraiture, landscape, etc.) it is unlikely
that you'll need many movements. For catalog layouts, studio work, or
architectural photography more movements may be necessary.
Basically these are all choices YOU have to make.
> Anyone have any ideas on back rotation? Spring back construction? I
> saw graflock backs on two different cameras, but in absence of one of
> these mechanical marvels, how would you manage the spring part of this
> back, I was considering breaking a couple mouse or even rat traps to
> make center mounted spring arms. I am sure someone has already come up
> with a better way.
"Better" is one of those words that has no meaning without
comparison. YOU need to figure out how YOU want to do it, and what YOU
think that YOU can build. If as you say, you looked at all of these other
cameras you should now at least have some ideas. I've already offered a
few of my own in a prior post. You may also want to browse some of the
construction sites that you can find on the list's new web page at
<http://rmp.opusis.com/cameramakers/cameramakers.html>. I think that John
Grepstad may also have an FAQ, but I'd need to go check.
Basically, there is no "right" way to do this. This is where you get to
be creative <grin>.
> I also say a fresnel on one of the viewing scrren, this may sound
> naieve but it looked exactly like those full page magnifiers that you
> use on a small print book. Would one of these work or is ther some
> special quality that they need to possess?
A Fresnel lens is often added behind the ground glass to bend the diffused
light from the screen back towards your eyes. This has the effect of
increasing the apparent brightness of the focusing plane. That is helpful
in low light conditions. I have used one of those "full page
magnifiers" in my camera. It works, but the ruling in this kind of
magnifier are fairly coarse, and I find them to be a bit distracting for
fine focusing. I wouldn't worry about this on a first camera.
> While I am on this, how big is an actual ground glass for a 4x5?
Uh, well ... it has to be at least 4x5. Basically it has to fit the
ground glass frame. How big are you planning on making your frame?
> What is the purpose of the lines. Some had a grid, some had little
> corner hash marks some didn'thave any lines at all.
These are guides that you can use during focusing. They give you a
reference for parallelism so you can make perspective corrections etc..
For example, they can help you determine if the sides of the building you
are photographing are parallel.
> If I make my own glass, could I just pencil these on?
Sure, or print them on overhead transparency material and tape them to
your ground glass or ...
> What is the normal thickness of a ground glass, looked like 1/8" or
> so, guess I could steal one out of one of those dimestore picture
> frames and frost it somehow.
Yes
> Is it only frosted on one side?
Yes, on the image forming side.
> Could I just get that etching cream or do I have to take ti to a sand
> blaster?
Don't know about etching cream. A sandblaster works, carborundum and some
elbow grease works too. You can also purchase bulk ground glass from
several places. Edmund Scientific is where I got mine.
> Lenses seemed to all be on something like a 4"x4" (or possibly
> 10x10cm?) lens boards is this a standard size? If it is, what are the
> exact dimensions of these lens boards, how thick are they?
This is your camera system. How big do you want your lens board? How
thick are you going to make it? These are all YOUR choices.
- Wayde
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