View Full Version : Agus35 not doing so well.


Trevor Trombley
June 4th, 2004, 01:00 PM
It's been an uphill battle.

First it was a real pain finding a good case to house my Agus, I was hoping to purchase a 6X6X3 sized plastic project box, but i couldn't find one, hell i couldn't even order one.

So I opted for an aliminum box. Which created a problem, how to get it cut? So I had to pay a milling shop to do so.

I also got a metal part to connect to by box that had the same thread as my 37mm Camera lens. With this little part I could screw on a macro lens, or just the camera itself.

Then I got the wood interior part built for me for free.

Assembled the little bugger and encountered some problems.

The SLR camera lens hole, and the Camcorder lens hole, aren't 100% aligned, which creates vignetting in the upper portion of the image. If that wasn't bad enough, even with all three Macro lens stacked, and even a 4th UV filter stacked on, the Camera still doesn't zoom in far enough to eliminate vinetting. Sure there's already the problem about the allignment being off But I don't even think it would work if the allignment was 100%.

What the heck is going on with these macro lens, they should be doing their job, but they're not, and the adapter keeps getting more and more cumbersome.

SIGH

Bob Hart
June 4th, 2004, 09:11 PM
Trevor.

The holes themselves may be correctly aligned if the shop did the job properly.

If it was properly done, then the problem may be the faces. They may have become not parallel due to latent stresses in the box being relieved by the holes being made, especially if they are close to the corner of a pressed or cast piece.

You would have to use two straight edges like metal rules place them across the faces and measure between the ends of the rules. They should be equal if the faces are parallel.

There is another wrinkle however and this involves the relay path into the camcorder. GG >> MACRO LENS >> Camcorder Lens >> CCD.

The Sony PD150P and one of the Canon camcorders, appear they might been made with an intention of upgrading the 4:3 CCD wedge with a native 16:9 version.

On my PD150P, the lens centreline does not co-incide with the CCD centres but is offset to the right and also slightly high, as viewed through the viewfinder which would put it near centre of a native 16:9 chip if it was built with the same vertical height.

When you do manual alignments of the Agus pieces on a jig, everything looks fine because you have matched by eye through the viewfinder. The trouble starts when you do some precision work to an optical centreline when you build the adaptor. Whilst it is optically true with the camcorder lens set, it presents off-centre to the CCD. This abberation doesn't matter a fig to the camcorder in the application it was designed. The problem is we are extending its talents beyond the original intent.

You will observe this offset effect with some of the night-vision from conflict zones which have been shot with the zoom set wide on the intensifier display for better definition.

The only solution is to zoom in closer and lose some of the image, or to offset the camcorder lens centre relative to the macro lens centre which is feasable but a precision workshop job out of our league.

Noe of these defects may be present in your project. Please let us know what camcorder you are using and perhaps make some .jpg pics on a flatbed scanner of your adaptor with a steel rule alongside in the images as a reference. If you ask Chris Hurd here via email chris@dvinfo.net, he may create an address here for your images to be posted.