This has probably been asked but can I get an explanation as to why I would need an expensive add on lens to get 235 images on a 235 screen.
I understand that the addition of the lens might be better in all respects but they are cost prohibitive.
Rationally, nothing really, and I am a pro Anamorphic lens user. There are benefits to using a lens, mainly in preserving brightness for larger screens, and better pixel density (even for 1080p), but zoom methods have improved, especially for high definition projectors, that it is much more tolerable.
I will use the fL (Footlambert) reference for brightness below, with 12 fLs considered the lowest reccomended, and 16-20 fLs ideal. These are not set in stone, but are benchmarks. Brightness is preference.
I will say on the defense for A-lens that if you are planning to drive a really big screen, you will need all the brightness you can get. A-lens typically lose about 10% of the brightness compared to unzoomed 16:9. When zoomed, you typically lost about 25% of image brightness compared unzoomed. If you were to drive a 20 foot wide scope screen and only have 2000 calibrated lumens on a 1.0 gain screen. If you were to do this zoomed (2.35:1) you will get about 8.9 fLs (Footlambers). If you were to use the 20 foot wide (2.35:1) screen at 15 foot wide 16:9 unzoomed, you will get 15.8 fLs. When placing the A-lens in front of the unzoomed 16:9 image, which will appear to form in the 20 foot wide (2.35:1) screen, you will get 14.2 fLs. That is a big difference. This does not count with the bulb aging which will reduce brightness overtime.
Of course you can always go for a brighter projector/ higher gain screen to fix this, but there will be differences in brightness compared to using an A-lens or using a 2.35:1 projector (which aren't out, but are the most consistent).
Edit: The numbers are a bit off, anyone have a more accurate number for the zoomed picture?