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renon
01-09-2010, 04:16 AM
I had some problems with this thread, first where to put it and second how to name it. It's a little bit of everything in this thread. Sorry.

Stimulated by Evan's thread (http://f295.f295.org/uploads/Blah.pl?m-1262450692/) and a photographic magazine about 3D I had the desire to try 3D also. So I built first a focusing rack.



Attached files http://f295.f295.org/uploads/img_0310_121.jpg (http://f295.f295.org/uploads/img_0310_121.jpg) http://f295.f295.org/uploads/img_0309_1498.jpg (http://f295.f295.org/uploads/img_0309_1498.jpg)

renon
01-09-2010, 04:20 AM
For a first quick test I used a Canon 500D with a 0.25 mm pinhole. Here the setup. Overlook the mess in my study room. :)

Attached files http://f295.f295.org/uploads/p1090610_3669.jpg (http://f295.f295.org/uploads/p1090610_3669.jpg)

renon
01-09-2010, 04:20 AM
The anaglyph result

Attached files http://f295.f295.org/uploads/img_0304_0305_anaglyph_bw_1821.jpg (http://f295.f295.org/uploads/img_0304_0305_anaglyph_bw_1821.jpg)

renon
01-09-2010, 04:22 AM
The cross view version in case you don't have any red/cyan glasses. I'm no longer able to cross view since my cataract surgeries. So please give me a feedback if you can see it, please.

Attached files http://f295.f295.org/uploads/img_0304_0305_crossview_web_7392.jpg (http://f295.f295.org/uploads/img_0304_0305_crossview_web_7392.jpg)

renon
01-09-2010, 04:38 AM
And finally the standard 2D picture. It is possible to take pictures with a digital SLR but you can clearly see that the quality is inferior compared to an analogue picture, even taken with 35 mm film. The digital picture is not so sharp (I'm using the same 0.25 mm pinhole on an analogue SLR with very good results) and caused by the small sensor the resolution is inferior. A full size digital SLR would be better but I'm not willing to afford such a lot of money for a digital camera.

The Certo Certix camera is the oldest fully working camera I have. I bought it last year for 4 Swiss franc (~ 4 USD). The camera works perfectly after dismantling the lens/shutter system and cleaning it. The original bellow is still light-tight! I made the experience that the bellows of the cameras built before WW II are usually much better than the bellows of the cameras built after WW II. The lens is uncoated, but excellent. Such a 4 USD 6 cm x 9 cm camera can beat a digital camera also in the next years regarding picture quality.

Here a few specs of the camera:

- Folder camera built 1934
- 6 x 9 film format ( 58 mm x 88 mm), 120 roll film
- Shutter: 1/100 (measured 1/60), 1/50 (measured 1/45), 1/25 (measured 1/20), B, T
- Aperture: 6.3 - 32
- Lens: Schneider-Kreuznach Radionar 6.3/10.5 cm

This camera has a self timer (marked red) too, but never touch self timers on such old cameras. This is the major reason for jamming shutters. Attached files http://f295.f295.org/uploads/img_0304_web_280.jpg (http://f295.f295.org/uploads/img_0304_web_280.jpg)

banana_legs
01-09-2010, 08:49 AM
René,

The rack looks great! The cross-eye set of images work fine and the composition works really well for the stereo view.
How far did you separate the images? I have grand plans for a twin image camera where I can adjust the separation ....

You had a bargain with the Certo. I have a plate camera that although now unmarked, I am pretty sure was made by the same company and is a similar vintage.

Don't tell everyone about the timers though; I have had a number of folders over the years off ebay where someone has cocked the self timer and it has all jammed and so sold it cheaply. I am getting pretty adept at stripping them now! If you can get the timer working reliably, it does make life easier with longer exposures (I have many shutters with speeds down to 1 sec).

Best regards,

Evan

renon
01-09-2010, 08:28 PM
Evan, many thanks for your kind comments and the feedback about the cross-eye picture.

The rack works very well, was extremly cheap and was easy to build in a short time.

Following the 1/30 rule I separated the pictures by 16 mm. The distance to the object was about 50 cm. With other objects I made series using different sepratations and got the impression that 1/30 of the object distance is a good value. In the meantime I read a few complicated articles in the internet about correct separation distances. For optimum 3D pictures you should choose a separation distance depending on the object distance and the focal length of your camera. In addition you should shift the lens or the pinholes to the center with shorter object distances. I think I will not make it too complicated at the moment.

I started to build a 3D 6x6 pinhole camera with a separation of 6.4 cm. This should be good for object distances between 1.5 and 3 m. The focal length is 63 mm. I plan to use it for taking 3D pinhole pictures of people.


Don't tell everyone about the timers though; I have had a number of folders over the years off ebay where someone has cocked the self timer and it has all jammed and so sold it cheaply. Good argument. :)

I have two old Certo plate cameras. Both are in a very good condition (the bellows are still light-tight), but I had not yet the time to clean the cameras and to make a film/paper holder.

polka
01-28-2010, 01:49 AM
René, I have (maybe exactly) the same folder as you, and can confirm : it take very precise pictures. But I did even get it cheaper (it's a family camera and knowing that I collected old cams, my cousin gave it to me). One thing that may differ with yours is that mine is biformat : it has two red peeping holes for the 6x9 view numbers, so when you use both alternatively, you step the film forward by half frames, and with a suitable cache (which I home-made, because the original was lost) you can also take 645 pictures.

Paul