I thought DX is long gone....

[Ilkka Nissilä]

Ask him. He can speak English. I am neither interested in deep space or planet photos nor do I know much. I just like the simplicity of his approaches and the fun that people do not believe the open construction can work until they see the results. The idea to get high resolution still images from video feeds with and without color filters seems very interesting to me and I ask myself what would be gained or lost if the video feed came from a D500 or D810A.

The planet images are very impressive. I guess this approach is ideal for relatively bright but small subjects (in terms of their angular diameter) such as the planets and moons. On the other hand, if there is stray light, deep sky objects may be difficult to see because they're very dim and some kind of shielding from stray light would seem to be necessary.

I don't know if use of a D810A has any advantage for use as a video camera for planets; it is relatively low resolution (1920x1080 in an FX frame) and I don't believe it uses all the sensor data in the interpolation to calculate the video. I am sure there are a number of cameras which give a more optimal video for the imaging of planets; smaller sensors with higher pixel densities and full use of the sensor data without line skipping. The D810A is more of a deep sky camera which doesn't require a separate computer in the field.

[bjornthun]

Almost any camera can be converted for astro photography, UV, IR, H-alpha, etc. by services like Kolari Vision, Lifepixel, etc. So there are many cost effective options for getting an astr camera. A full spectrum mod could be combined with filtration in the telescope, and thus be much more versatile in application than just H-alpha.

I think the D810A has a filter stack modified for H-alpha.

[Akira]

Ask him. He can speak English. I am neither interested in deep space or planet photos nor do I know much. I just like the simplicity of his approaches and the fun that people do not believe the open construction can work until they see the results. The idea to get high resolution still images from video feeds with and without color filters seems very interesting to me and I ask myself what would be gained or lost if the video feed came from a D500 or D810A.

For this thread it was only a hint that one can build 3 meters focal length for relatively cheap.

The ancient long space telescopes didn't have the lens barrels.  The light pollution was non existent then.

If you use the video feed, D500 should be a better option except for capturing the H-alpha spectrum.  D500 shoots 4k.  However, the noise performance of DX sensor may limit the usage...

[Frank Fremerey]

Thank you Akira.

[Ilkka Nissilä]

The D500 has a further crop in 4K video mode which may actually be in the photographer's favour in this case, as I believe the camera to make the image without line skipping (so 4K is approximately a 2:1 aspect ratio 8MP crop from the center).  However, there is no enhanced red sensitivity at least without modifying the camera.

[Valerie S.]

My strong preference is for FX but there is a place for DX and I would like a Nikon D500 for telephoto, close-up and macro.

I only use my D500 as a teleconverter. Otherwise, it's FX (D5) all of the time. IMO, the files have more "pop" - more than just a shallower DoF and can take a more aggressive crop than D500 files.