[Konvas] Anamorphic Question

[Steve Morton]

The bokeh and flares associated with anamorphic lenses is largely a 
characteristic of "upfront" anamorphic optics. Rear of zoom (or long 
lens) anamorphic adapters usually don't produce these visual effects.

If you were to use lomo square or round front anamorphic lenses on a 
DSLR that outputs say 1080 HD what would you get with the 2:1 horizontal 
compression? For the moment let's forget about the size of your DSLR's 
sensor and whether the image from the anamorphic lens "fills" the HEIGHT 
of the sensor, let's assume it does.

Obviously the 1080 HD output from the DSLR is 16:9 but you want to end 
up with 2.35:1 using a regular cine anamorphic lens which has 2:1 
horizontal compression. So you will be wanting to use the centre section 
of your 16:9 1080 HD and end up expanding that out to 2.35:1. Therefore 
you will using the centre 1.175:1 of your 1080 image (1269 pixels wide).

Some years ago ISCO made an anamorphic lens with 1.5:1 squeeze 
(Iscorama54) and these lenses often came in a Nikon mount. They once 
sold on ebay for about US$200 - 250. Now they are attracting bids many 
times this amount, see:
http://cgi.ebay.com/_W0QQitemZ230424014683
http://cgi.ebay.com/_W0QQitemZ150404676486

The ideal compression ratio to use on a 16:9 (1080HD) camera to give 
2.35:1 output is 1.3:1. So the quickest way is to use a 1.3:1 
supplementary anamorphic lens on the front of the regular lenses that 
come on your DSLR.  Of course the image quality will be compromised and 
the use of wide angles will be limited.

A foton 37-140mm zoom with the front anamorphic "adapter" (2:1 
compression) might give a better result than using 1.3:1 supplementary 
anamorphic lens, might not, I don't know. Someone might have the bits to 
test this...

All the best
Steve