The 18-55 kit lens, taking the 1.6 crop factor into account, is 29-88mm, so 40mm is achievable. I tried it at various focal lengths, but even at the 29mm end, its still a much magnified image, compared with the visual view through the same eyepiece.Hobbyst46 wrote:Dave, for afocal setup, the appropriate focal length of the canera lens, for an APSC sensor, when the eyepiece is 10X, is 40mm. The zoom should be set at 40mm and pre-focused at infinity. Both settings can be mechanically fixed on the zoom lens by means of a turn of cellotape wrap.Dave S wrote:I made up a crude adapter to place the 18-55 lens on the eos4000d against the 10x eyepiece in the photo tube (afocal), and the image was not as that seen visually, but quite magnified by the sensor.
I'm still convinced that replacing the 10x eyepiece in the photo tube, with a 2x would bring things down to a sensible level, but it is a £103 gamble to try the AMscope one.
If I buy a separate 2x eyepiece, I would need to be sure that it isn't of the compensatory type, as according to Bresser, their objectives don't have CA issues. I would tend to agree with that, as I haven't seen any evidence of CA.
Thanks for the 'heads' up on the Nikon eyepieces Michael. I guess that new, they would cost more than the EOS4000d
As I said, doing afocal with the iPhone, and its small sensor, I get a very comparable result to the visual view.