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06/23/2007 10:32:23 AM · #1
This evening I decided that my holga, having fallen out of use recently should be disassembled and the lens used on my Nikons... After reading a few tutorials on this I have managed to make a quick mock up of the lens...
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I'm having two small issues and I'm wondering if anyone might be able to help with either. The first issue is that it's just too damn good quality... I've countered this a little by using some cardboard to 'simulate' the vignetting of the original holga... any other ideas? The other thing is focus distance... currently it is fixed at around 2.5 feet... the trouble is, to focus further away it seems I need to move the lens closer to the focal plane. The problem here is that would mean moving the lens inside the camera, not really possible, any ideas?

Here's a sample shot from this lens as well...
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06/23/2007 10:37:23 AM · #2
I just ordered one of these lens for my Evolt off of eBay this AM!!! Sorry I don't have any tips for you. Maybe check with ericwoo since he is the only other one on the site (as far as I can tell) that has one of these.
06/23/2007 06:34:24 PM · #3
Originally posted by shalrath:

... The other thing is focus distance... currently it is fixed at around 2.5 feet... the trouble is, to focus further away it seems I need to move the lens closer to the focal plane. The problem here is that would mean moving the lens inside the camera, not really possible, any ideas?


could you get or make a tube extender to move it closer to the subject? I know I saw a thread here some where on making one. This also might help with adding some vinegetting, otherwise maybe something like a piece of exposed negative cut to size, not sure where you would get this though.
06/23/2007 11:08:01 PM · #4
What I'm trying to do is focus further away from the camera, not closer to it. This is where I'm having the trouble.
06/23/2007 11:25:04 PM · #5
Try it with a telextender if you have one. Maybe the depth of the front of the telextender will be shallow enough to allow it to focus more distant. I don't really think it will work, but may be worth a try.
06/24/2007 12:15:50 AM · #6
I made up the following as I went along. In the spirit of all good hypothesizing it may be a load of old bollocks.

To focus further away you need to move the lens closer to the imaging plane. I don't have a Holga to play with but from what I've read it uses a single piece 60mm convex/concave lens design. This means that the infinity image will come into focus at a point 60mm behind the center line of its single lens element. The Nikon F mount has a flange to image plane distance of 46.5mm. In theory therefore the simple Holga optics can be made to focus on the Nikon sensor without having to intrude into the mirror box. However the diaphragm and lens structure are probably going to get in the way and the lens focus mechanism is liable to be upset by cutting lumps off it.
It is possible to extend the back focus by using a low power diverging lens element between the Holga and Nikon. It would introduce lots of nice distortion etc. You could get one from just about any old camera lens. Stick it in place as close to the back of the Holga lens element as you can get. It should be awful (assuming it works at all)- just what you are after :o) Of course, if you go so far as to pull apart a perfectly good old lens in order to make a perfectly awful lens work on a camera for which it was never designed then you are as daft as I am.

Mike

Message edited by author 2007-06-24 00:19:11.
06/24/2007 12:19:49 AM · #7
A set of bellows would do the trick methinks...
06/24/2007 12:26:47 AM · #8
Originally posted by MK153:

A set of bellows would do the trick methinks...

He need to get the lens closer to the camera to achieve infinity focus. A bellows would move it further away and make it into the worlds worst macro lens... which could be interesting :-)
06/24/2007 12:35:18 AM · #9
If the lens is only one piece, and not a combo of elements, then try shooting with it backward. This would allow you to get the one element closer to the sensor. You might also get the vignette by closing the aperture some with it this way.

Message edited by author 2007-06-24 23:32:16.
06/24/2007 04:45:49 AM · #10
Or... you could try saving yourself, and everyone here, a lot of time and take a hammer to it? Just a thought!

:D
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