Posted 17 August 2005 - 10:36 PM
I am setting up a Mitchell BNC, with BNCR lens mount on the L-plate, for transferring digital to film. I intend to do the anamorphic squeeze through the lens. I have been in contact with "Realrus" on Ebay. He recomends the OCT19 round front with BNCR mount converter ring. My concern here is which length would best suit my situation. I will be shooting a flat LCD or CRT surface. The likely subject area will be roughly 28.5 inches horizontal dimension. I wish to record the screen with the best clarity accross the entire subject area. I would like to avoid all abberation as well as focus variation. Is it correct to assume that longer lenses will deliver better results? If not, what lens length would you suggest? I know so little about scope lenses. I am currently trafficing under the assumption that scope lenses must be twice the lenght of flat lenses to match the same subject area dimensions. Is that correct or am I a total ignoramous?
Thanks in advance for any help,
Posted 18 August 2005 - 06:25 AM
But first of all - the anamorphic lenses for film have a 2x squeeze ratio, not a 1,33x as the video ones from Century and Optex. This is significant because if you have 16x9 squeezed image this will not remedy the problem after going to an anamorphic lens for film - the image will still be squeezed after projection. You can make it work, but it involves masking in the camera or on the LCD. But maybe you all knew this.
As for Lomo's specifically you are correct in the assumption that the longer lenses deliver less abberations. The 35mm bends like hell and should be avoided. Even the 50mm bends slightly at the very edges. I'd say go for a 75mm. The 100mm and the 150mm are slower and have more glass in them (they're basically 50 and 75mm with 2x extenders built in), so the 75mm is often the sharpest.
If you go for the older square ones, go for the 80mm.
Posted 18 August 2005 - 07:58 AM
Posted 18 August 2005 - 10:59 AM
Thanks for the info. I can control the exposure times. So, I'm inclined to go with the 200mm. The square fronts are cheaper, but RealRus emphasized the round fronts. He may know something about them that isn't just obvious. The again, maybe, he wants to sell the pricier lens. Either way, the Lomos are affordable.
Again, thanks for the help. It's good to hear from you guys again.