Wide lens for Technika III?

Hi can someone point me towards a suitable wide angled lens for a Technika 3 type 5. I have the 150mm standard lens, which sometimes isnt wide enough for landscapes and stuff. Not sure what to look for.
I think something in the 90mm range would be good.
Also would be good if I didnt need a recess board.
Also also would be good if I could still fold the camera with lens, but not totally important.
As well I have a later technika board that is too wide for a iii, can I just trim the sides to fit? Cant see why not.
Thanks

If you've been shooting 35mm or medium format, take a look at these charts to help you decide:

Dead Link Removed

http://lensn2shutter.com/35mmchart.html

http://lensn2shutter.com/angleofviewchart.html

I don't think you would need a recessed board for a 90mm lens. A few lenses can be kept mounted on the camera even when it is closed - the 120mm Angulon, 90mm f/6.8 Angulon and the Wide Angle Congo 90mm f/6.3 come to mind. I could get you a 90mm Fujinon or Super-Angulon.

Rather than cutting up a perfectly good board, you could get one that will fit your camera for a small sum, or make one out of plywood.

Kumar

I have a 100mm f6.3 Wide Field Ektar in flash supermatic shutter for $$$ that will fit the bill.