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There are some reflector lenses available for SLR cameras, not everyone likes their different optical properties though.

dekhn 3y ago
I have one of these- a 500mm "equivalent" (https://www.amazon.com/gp/product/B004WLEEHI https://www.amazon.com/gp/product/B004WLEEHI) and it's definitely got weird optical properties.
- namibj 3y ago
  Sadly sensors are all bundled up with the rest of the camera, because a Schmidt camera (corrector plate like your objective, adjustable primary mirror, sensor directly in the primary focus with it's back facing the scene) can easily get a very wide aperture (e.g. nicely matching a CMV12000 with a fairly tame single glass up front and a tame mirror in the back, plus a slab and a plano-convex lens right at the sensor to flatten the field/focus, yielding 400mm f/2.0, though that's with the focal point dead center in the sightly over 800mm tube; still around f/2.4~f/2.8 brightness to the full f/2.0 sharpness (near center, but even at the corner you need a monochrome sensor to feel the mushiness)). Celeste's prosumer 8~14" (aperture) Schmidt-Cassagrain typically support replacing the secondary mirror with a camera mount to get that much shorter focal length (IIRC around f/5). Might be nice with one of those very narrow studio video camera bodies (e.g. Black magic has some); the catadioptric nature means you can carry even the very big ones on your shoulder (I'd highly recommend a gimbal if used for shooting from the shoulder).
  - dekhn 3y ago
    I'd like to understand what you're saying better. I mainly purchased that "lens" because it was the most affordable way to upgrade to a higher magnification on a DSLR. But for another purpose (solar imaging), I'm actually moree interested in using machine vision cameras with C-mount. Aperture isn't super important because the sun has lots of photons (so many I have to use a filter that fits to the lens) but a flat field is dfinitely desired. I like the sensor you mentioned (CMV12000) but I assume it's obscenely expensive... $20K
    - deleted 3y ago
      [deleted]
    - namibj 3y ago
      No it's 2k$ last I checked.

dekhn 3y ago

I have one of these- a 500mm "equivalent" (https://www.amazon.com/gp/product/B004WLEEHI https://www.amazon.com/gp/product/B004WLEEHI) and it's definitely got weird optical properties.

namibj 3y ago
Sadly sensors are all bundled up with the rest of the camera, because a Schmidt camera (corrector plate like your objective, adjustable primary mirror, sensor directly in the primary focus with it's back facing the scene) can easily get a very wide aperture (e.g. nicely matching a CMV12000 with a fairly tame single glass up front and a tame mirror in the back, plus a slab and a plano-convex lens right at the sensor to flatten the field/focus, yielding 400mm f/2.0, though that's with the focal point dead center in the sightly over 800mm tube; still around f/2.4~f/2.8 brightness to the full f/2.0 sharpness (near center, but even at the corner you need a monochrome sensor to feel the mushiness)). Celeste's prosumer 8~14" (aperture) Schmidt-Cassagrain typically support replacing the secondary mirror with a camera mount to get that much shorter focal length (IIRC around f/5). Might be nice with one of those very narrow studio video camera bodies (e.g. Black magic has some); the catadioptric nature means you can carry even the very big ones on your shoulder (I'd highly recommend a gimbal if used for shooting from the shoulder).
- dekhn 3y ago
  I'd like to understand what you're saying better. I mainly purchased that "lens" because it was the most affordable way to upgrade to a higher magnification on a DSLR. But for another purpose (solar imaging), I'm actually moree interested in using machine vision cameras with C-mount. Aperture isn't super important because the sun has lots of photons (so many I have to use a filter that fits to the lens) but a flat field is dfinitely desired. I like the sensor you mentioned (CMV12000) but I assume it's obscenely expensive... $20K
  - deleted 3y ago
    [deleted]
  - namibj 3y ago
    No it's 2k$ last I checked.