[Elphel-support] Reasonable motorized lenses for 50-60 meters zooming for Elphel camera

[Andrey Filippov]

>
> So, if I still with motorized zoom then am I right with H10Z1218MS
> 12-120mm? Or others? Under $1k it is ok to such lenses for me. I didn't find
> any fixed length above 100mm for 1/2" Format at Computar pricelist.
>

Roman, I'm afraid that resolution of that lens is far from what is needed
for the senor. There is no resolution data provided, but as it does not say
"5 megapixel", "3 megapixel" or even just "megapixel" it is likely good only
for low resolution cameras. So you will probably get the same details (at
maximal zoom) as with good lens of some 25-30mm focal length. 75-mm Fujunon
HF75SA-1 ( http://rmassa.com/specsheets/HF50SA75SA-1.pdf ) will definitely
be better But the field of view will be still of the 120mm one,
unfortunately. You need top resolution, not just some regular video-security
lens. Maybe you can try C-mount-to-[Canon,Nikon,other_larger_format_lens]
adapter and get better results. You just need a lens that will provide >=150
lp/mm


>
> Yesterday have experiments with your camera with standard lenses. Tryed to
> focus on faces when they would 200 pixels height. In camera's center and by
> sides. For my purposes side faces is still recognizeable :) So if it will be
> the same quality (center/side) on zooming it better for me without any
> additional mechanic.
>

What kind of lens did you use? Focal length? Distance?
How are you going to deal with the fact that having 150 pixels per 200 mm
will result in just about 2m x 3m field of view (without the mechanical
platform)? Will it be enough for you application?

Andrey
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