The focal length is a calculation. Based on the distance of the light travel once entering the telescope and it's mirror (aperture) diameter. Hard to explain. The light comes into the scope, travels down to the primary mirror, is reflected back up the scope to the secondary mirror, then reflected once again back down through a hole in the centre of the primary mirror to the camera behind the scope. Therefore the telescope's native focal length is just under 2500mm. Now put in a 2.5x Barlow lens you have effectively doubled it. It's all about getting the image scale up so you can fill more of the chip with a small object like a planet with a small angular distance.When you say you need 6m focal length on the new CF open frame 'scope to zoom in far enough, does that mean you can literally push that front (collimator? lens? mirror?) end out of the dome hatch? Or buy screw-on extension frames or something? Or did you just mean you were limited to 2.7m regardless of what the subject needed?
My deep space camera is a CCD still camera, which is cooled with a peltier cooler and fan behind the chip to keep it 30 degrees below ambient air temp. It takes exposures as long as I like. Typically my exposures are 5 to ten minutes each and I take 20 or 30 exposures of a target for stacking. The advantage is that a CCD imaging chip over a CMOS chip in a DSLR is that it is less affected by digital noise plus it is cooled, reducing noise.What's the difference between your star camera and the planet camera? Do they have built-in sensitivity settings or fixed lenses or something? What's the advantage of those over a DSLR mount?
My planetary camera is a high-quality video camera, (typically seen in medical faculties to photograph biopsies etc.
which takes up to 60 frames per second. 3 minutes of video on a planet may yield thousands of fames to be sorted and stacked to produce a final image.
I don't really go dancing around the telescope once it's imaging. Late at night vehicle movement is minimal to zero. But yes, the entire telescope mount sits on a pier that is full of rio, concrete and isolated from the main building, sitting on a cubic metre of concrete underground that is also isolated from the main slab via 25mm thick polystyrene foam.Is the steel I-beam construction sufficient to deaden your/vehicles' vibrations? Is the whole thing (or just the scope mount) on an isolation pad? I'm assuming even though you're stacking to avoid thermal noise, that each shot is probably about 30 seconds to get the hours of exposure time necessary, but if you mentioned vibration isolation I must've missed it. Maybe it gets averaged out by the stacking software, but I would think at those focal lengths it'd get pretty important.
I did. It's on the front page of my website. www.asignobservatoryii.comOh, and did you ever get the video for the BH&G segment? I saw the other two interview links, but wanted to see that one in particular.