Changing Your Mind Half Way Through Building...

[Steve Smith]

I had a similar problem when I was building my 3rd log cabin. ummmm very similar!

At least you had a roof over your head whilst you built the next one... you did get as far as putting the roof on didn't you?!!!!


Steve.

 

[Jim Jones]

There are well-proven alternatives to rack and pinion focusing for the home camera builder with limited funds or tools. With the New Vue twin-rail view camera, rough focusing was done by sliding and locking the front standard, and focusing the rear with a lead screw. The Noba studio camera used a V-belt system for focusing. Flexible line secured to the standard and wrapped several turns around a focusing shaft might also work. Some Polaroids used a lever for limited range fine focusing.

 

[Steve Smith]

Flexible line secured to the standard and wrapped several turns around a focusing shaft might also work.

Like the pointer mechanism in a wireless tuning control.


Steve.

 

[E. von Hoegh]

Changing your mind partway through isn't neccesarily a bad thing; it means the design is evolving in your head. John Arnold said "I have a hundred number ones".

 

[himself]

I know this feeling, but you know, I decided that it's better to finish what you have started, not out of some stubborn need to prove that you can, but because it's better to continue, but keep your design fluid. That way you'll have a finished frankencamera of ideas that have been tried fleshed out, then you start another knowing, in a practical reality, what will, won't and can work.

First ideas or thoughts seldom turn out how you want and, to leave you with another platitude, practice makes perfect

 

[Toffle]

Quite the timely thread. I wish everyone good fortune in their building.

I am in the design/parts collecting phase of a folding 4x5 project. My design as well includes dual focusing racks, and on paper I am quite pleased with how things are working out. (Many, many sheets of paper) I am seeing some different approaches to the rack and pinion design, and I wonder what others have done to achieve smooth and consistent focusing.

I may have dealt the whole idea a death-blow today by deciding to make my own ground glass and back. I have built pinhole cameras before, but nothing where focus is critical. I have measured a couple of film holders and seem to be getting just under 5mm depth between the rail and film. (4.87mm, to be exact) I am assuming that would be the depth of the ground glass as well.

BTW, I am doing my rough design by hand and then doing a more detailed 3D rendering using FreeCAD. This gives me a much better idea of how things will fit together.

I am hopeful, as well to make my own bellows, but I am not above blowing a bit of my budget on commercially made bellows if it will help finish the project.

Cheers,
Tom

 

[Dan Fromm]

Tom, measure the distance with film in the holders, and look for the ANSI (no doubt now ISO) standard for 4x5 film holders. Film isn't infinitely thin.

Re walking away from a mistake, if it can't be saved why waste time and effort and love trying to save it?

 

[Steve Smith]

Re walking away from a mistake, if it can't be saved why waste time and effort and love trying to save it?

Absolutely. Learn from it and try again.


Steve.

 

[himself]

but isn't it only a mistake if you don't rectify it?

and why be so prescriptive with your design...

 

[Toffle]

but isn't it only a mistake if you don't rectify it?

and why be so prescriptive with your design...

And why be so proscriptive yourself?

Steve does what works for him, and is willing to share his perspective with us. As one facing similar challenges and choices, I appreciate his efforts and I thank him.

Cheers,
Tom

 

[Steve Smith]

but isn't it only a mistake if you don't rectify it?

Not necessarily mistakes. Just getting to a point where I realised that what I was making wasn't quite what I wanted - but I wouldn't have known that if I hadn't got that far.

I'm not like normal people. I rarely try the easy route first.

As an example, when I first made an acoustic guitar, everyone I spoke to suggested I started out with a simple Spanish nylon strung design. But that's not what I wanted.

I wanted a Selmer Modele Jazz (as played by Django Reinhardt). So that's what I built. Although in that instance I managed to get there without half building any other guitars first! (so not a very good analogy!!!).

In the case of the guitar, I knew what I wanted but with the camera, I wasn't sure at first.


Steve.

 

[himself]

Not necessarily mistakes. Just getting to a point where I realised that what I was making wasn't quite what I wanted - but I wouldn't have known that if I hadn't got that far.

I'm not like normal people. I rarely try the easy route first.

As an example, when I first made an acoustic guitar, everyone I spoke to suggested I started out with a simple Spanish nylon strung design. But that's not what I wanted.

I wanted a Selmer Modele Jazz (as played by Django Reinhardt). So that's what I built. Although in that instance I managed to get there without half building any other guitars first! (so not a very good analogy!!!).

In the case of the guitar, I knew what I wanted but with the camera, I wasn't sure at first.
Steve.

I see what you mean Steve, but planning can only go so far... so to speak.

I have plenty of half finished projects myself, so I know what you mean, just that I don't understand why you'd need to give up rather than trying to turn it into what you want?

and isn't that essentially what you're doing anyway? if you think of the one you start after the first, having learnt what you did from the one you began, as a continuation of the "project" rather than as a new "camera" then you have no half finished projects, just some trial designs.

 

[Steve Smith]

I think you have it absolutely correct. The half finished piece is still part of the same project if I learned from it when starting the next version.


Steve.

 

[Dan Fromm]

Steve, you may enjoy reading this: http://www.galerie-photo.com/baby-bertha-6x9-en.html

 

[Steve Smith]

You're right. I did.

Thank you.


Steve.

 

[himself]

I just wanted to add that if anyone wants to get rack (track) and pinion then you can sometimes get them in hobby shops. They usually stock the plastic type that come in about 100mm lengths, but can be clipped together to make a longer track. there are a couple of places on ebay that sell them too, just search plastic rack and pinion.

 

[Toffle]

Technobots sells these for a very good price, but I don't know if they are up to the task.
http://www.technobotsonline.com/gears/plastic-model-gears/plastic-rack-and-pinion-gears.html

 

[himself]

aye that's the ones.

I guess it depends on how much strain you'd put on it, right?
A modern lens and back shouldn't be too heavy for it I reckon.

 

[Toffle]

The price is low enough that I think it is worth risking if only to prove that it doesn't work.
BTW, I made the first concrete steps today towards construction after spending many an hour sketching and CAD'ing. Comments and suggestions are welcome.

Cheers,
Tom

 

[himself]

too true.

looks good so far, but I'm wondering why you've decided to make the back so bulky, not that it makes my difference, just could be thinner, so overall lighter.

anyway, you should for sure try, at least, making your own bellows once. You're camera will be 4x5, no?

not so hard then

 

[Toffle]

too true.

looks good so far, but I'm wondering why you've decided to make the back so bulky, not that it makes my difference, just could be thinner, so overall lighter.

anyway, you should for sure try, at least, making your own bellows once. You're camera will be 4x5, no?

not so hard then

Good call, Himself. The bulk is coming off slowly but surely with some 60-grit sandpaper. When imposing on the good will of a neighbour, you can't be too fussy about the results. My friend (with the $100,000 wood shop) preferred to allow for error by slightly over-sizing, so I am working away at the thickness. The wood is definitely sturdy enough to withstand a little thinner build.

Anyway, I shouldn't be hijacking this thread. I will post more results in a separate thread when there is more to report.

BTW, I am definitely going to give the bellows a shot. After all, I have YOUR amazing floral bellows as an example.

Cheers,
Tom

 

[Steve Smith]

BTW, I am definitely going to give the bellows a shot.

On the basis that you can never have too much information, here is my bellows method: http://stevesmithphoto.webs.com/bellows.html


Steve.

 

[Toffle]

Steve, that page has been open on my computer for about three weeks.
Us poor unwashed who don't have access to a laser cutter will have to try other things first.

Cheers,
Tom

 

[Steve Smith]

You don't need a laser to do it. Get the pattern printed out the right size, tape it to the stiffener material and cut through it all using a scalpel and a steel rule.


Steve.