Home

Please support mflenses.com if you need any graphic related work order it from us, click on above banner to order!
SearchSearch MemberlistMemberlist RegisterRegister ProfileProfile Log in to check your private messagesLog in to check your private messages Log inLog in

Tayloor-Hobson...A couple of new toys
Post new topic   Reply to topic
Home   Manual Focus Lenses
View previous topic :: View next topic  


PostPosted: Tue Oct 30, 2007 5:19 pm    Post subject: Tayloor-Hobson...A couple of new toys Reply with quote
To-day I got two parcels. The first one containing the most essential component of a camera looked like this:



and the second parcel one contained this:



Busy days ahead Smile

Veijo


PostPosted: Tue Oct 30, 2007 5:21 pm    Post subject: Reply with quote
Another Cooke! Am I right? Smile

The most essential component... is that money? Razz


PostPosted: Tue Oct 30, 2007 6:07 pm    Post subject: Reply with quote
Orio wrote:
Another Cooke! Am I right? Smile


Weell, with a spelling mistake: it says Tayloor-Hobson on the rim. I wonder whether this would be a collector's item like the postage stamps with something wrong with them Smile

Quote:
The most essential component... is that money? Razz


Not that, I don't buy money. But something about as flat.

Veijo


PostPosted: Tue Oct 30, 2007 6:46 pm    Post subject: Reply with quote
An original photo made with this coke ?

Anyway , ice tactic Veijo : everyone now has your postal address and thus we have no excuse not to send New Year gretting cards Wink


PostPosted: Tue Oct 30, 2007 7:59 pm    Post subject: Reply with quote
This is so interesting!

So...Veijo, you find these old lenses and then adapt them to camera bodies?

Are you a machinist, or do you simply work out solutions in other ways?

And does the envelope contain an original dated invoice? Shocked

What are you planning with this lens? I've GOT to know... Very Happy

Yours in complete interest, Laurence


PostPosted: Tue Oct 30, 2007 8:35 pm    Post subject: Reply with quote
Laurence, as far as the register focal plane of the lens is longer than the one of the camera body, you can virtually mount any lens on this camera :

http://galactinus.net/vilva/retro/eos350d_cooke.html

http://galactinus.net/vilva/retro/eos350d_radionar.html

http://galactinus.net/vilva/retro/eos350d_r50.html

and so on... => http://galactinus.net/vilva/retro/


PostPosted: Tue Oct 30, 2007 9:04 pm    Post subject: Reply with quote
niblue wrote:
I think the envelope contains sheet film.


I'll go for light seals. Smile


PostPosted: Tue Oct 30, 2007 9:12 pm    Post subject: Reply with quote
I say "holes for pinhole camera" Wink

-


PostPosted: Wed Oct 31, 2007 3:34 am    Post subject: Reply with quote
Orio wrote:
I say "holes for pinhole camera" Wink

-


Right Smile or to be exact, one hole:



I've got the body of the 6x9 folder from which I extracted the 4.5/105 Radionar and I'm turning it into a wide angle pinhole camera, "focal length" will be about 36 mm, which corresponds roughly to a 16mm lens on an FF 35 mm body. The horizontal FOV will be about the same as that of my Zero 2000, but the linear resolution will be about 17% higher. For the same aspect ratio, the "pixel" resolution will be about 36% higher, i.e. better than going from a 350D to a 400D.

Veijo


PostPosted: Wed Oct 31, 2007 4:40 am    Post subject: Reply with quote
Flor27 wrote:
Laurence, as far as the register focal plane of the lens is longer than the one of the camera body, you can virtually mount any lens on this camera :

http://galactinus.net/vilva/retro/eos350d_cooke.html

http://galactinus.net/vilva/retro/eos350d_radionar.html

http://galactinus.net/vilva/retro/eos350d_r50.html

and so on... => http://galactinus.net/vilva/retro/


Outrageous Shocked
I love it.


PostPosted: Wed Oct 31, 2007 7:47 am    Post subject: Reply with quote
vilva wrote:

I've got the body of the 6x9 folder from which I extracted the 4.5/105 Radionar and I'm turning it into a wide angle pinhole camera, "focal length" will be about 36 mm, which corresponds roughly to a 16mm lens on an FF 35 mm body. The horizontal FOV will be about the same as that of my Zero 2000, but the linear resolution will be about 17% higher. For the same aspect ratio, the "pixel" resolution will be about 36% higher, i.e. better than going from a 350D to a 400D.
Veijo


Ain't that fascinating? This man is a volcano of ideas.

Please keep us posted with the work-in-progress!
-


PostPosted: Wed Oct 31, 2007 8:09 am    Post subject: Reply with quote
Orio wrote:
vilva wrote:

I've got the body of the 6x9 folder from which I extracted the 4.5/105 Radionar and I'm turning it into a wide angle pinhole camera, "focal length" will be about 36 mm, which corresponds roughly to a 16mm lens on an FF 35 mm body. The horizontal FOV will be about the same as that of my Zero 2000, but the linear resolution will be about 17% higher. For the same aspect ratio, the "pixel" resolution will be about 36% higher, i.e. better than going from a 350D to a 400D.
Veijo


Ain't that fascinating? This man is a volcano of ideas.


There is nothing original in using a folder body for a pinhole camera. The only even slightly unconventional solution is keeping the body intact but closed, i.e. not opening the front/bed but drilling a 5-8 mm hole through it. This gives a still reasonably short pinhole-to-film distance. A shorter distance would have allowed using a smaller pinhole giving a slightly better resolution and a wider FOV at the expense of more vignetting, but it would have required either replacing or greatly modifying the front panel. This was a lazy man's solution and quite adequate for my purposes, perhaps even a reasonably optimal compromise between resolution and vignetting. Now the only missing item is a shutter - that may call for some inventiveness.

Veijo


PostPosted: Wed Oct 31, 2007 8:15 am    Post subject: Reply with quote
vilva wrote:
This was a lazy man's solution


Perhaps. But I would have been unable to come up with anything like that.


PostPosted: Wed Oct 31, 2007 10:13 am    Post subject: Reply with quote
Hello Veijo, could you kindly give a little more information about the hole itself? For instance the material and thickness, how is the 0.22mm dia calculated and why is it so critical, and how is it made to such fine accuracy? A pointer to where I can read this would be wonderful! Thanks


PostPosted: Wed Oct 31, 2007 11:04 am    Post subject: Reply with quote
peterqd wrote:
Hello Veijo, could you kindly give a little more information about the hole itself? For instance the material and thickness, how is the 0.22mm dia calculated and why is it so critical, and how is it made to such fine accuracy? A pointer to where I can read this would be wonderful! Thanks


Well, basically the optimum diameter of the hole depends on the distance between the hole and the film/sensor and, if you want to be very exact, also on the magnification. There are various formulas available to calculate this distance, which make slightly different assumptions. For normal photography, there really isn't an absolutely correct distance because each wavelength would require a different distance. So, in a sense the choice is rather arbitrary - within limits, of course.

In this case I took the easy way out and just selected the diameter suggested by the seller as I had got reasonably good results using his EOS lens cap pinhole on my 5D. Here is a link to his ad on eBay: http://cgi.ebay.de/Lochblende-fuer-Lochkamera-0-15-0-8-mm-pinhole-camera_W0QQitemZ170158354341QQihZ007QQ

These pinholes are slightly smaller than those suggested by some formulas, but e.g. the Zero pinhole cameras use these values. You can find links to pinhole articles on my pinhole page at http://galactinus.net/vilva/pinhole/

Veijo


PostPosted: Wed Oct 31, 2007 1:26 pm    Post subject: Reply with quote
peterqd wrote:
could you kindly give a little more information about the hole itself?


Peter, you may want to check the page on Robert Monaghan's Medium format Megasite about pinholes. The original website hasn't been functioning properly for months but, fortunately, we can access it through the Internet Archive:

http://web.archive.org/web/20060813173552/http://www.medfmt.8k.com/mf/pinhole.html

I have tried Mike Sinclair's trick with some aluminum foil, a capacitor and a needle to make a clean pinhole for cheap and I must say that it works very well. You can make holes of different diameters by varying the voltage and the capacitor's value.

Cheers!

Abbazz
Post new topic   Reply to topic
Home   Manual Focus Lenses
Page 1 of 1