8mm Forum: 16mm Len's Number Question

This is topic 16mm Len's Number Question in forum 16mm Forum at 8mm Forum.

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Posted by Scott Mallory (Member # 2393) on February 13, 2013, 10:01 PM:

Hi, I'm still new at this and I thought I remember hearing that you want a lower lens number for your projector, could someone please explain? My Eiki's came with F/1.4 so I got a F/1.2. I think it lets more light through? Now I'm thinking about getting a larger image lens, but it's a F/1.5. What are the cons, more flicker, not as bright picture? Any help would be greatly appreciated.

Posted by Dino Everette (Member # 1378) on February 14, 2013, 01:48 AM:

Scott you actually already have it.... For brightness you want to get as close to an f/1.0 as possible and for image size the lower the number gets the bigger the image will be (ie: a 1 inch lens will give a bigger picture than a 2 inch lens) BUT the bigger the image gets the less bright your picture will be, so you need to come up with the best compromise for your particular screening room, since you will want to fill your screen with the brightest picture.... You should not have to worry about flicker period unless you start messing with your shutter, which it sounds like is still a ways off for you....The other thing to think about is depending on the optics in the lens the general rule of thumb will be the bigger the picture the harder it will be to keep a sharp focus so a 2 inch lens will tend to be sharper than a 1 inch lens....obviously there can always be exceptions, but this is the general rule...

Posted by Scott Mallory (Member # 2393) on February 14, 2013, 08:06 AM:

Thanks Dino. My screening room is in a mid-sized room in the basement with a 8x8 screen. My Super 8 fills the screen but both of my 16mm projectors only look like a big screen TV on it, still lots of white space which gets frustrating. BUT it doesn't sound like the adapter with a F/1.5 lens will be my solution if I'm only going to get a big, fuzzy image.

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