T Mount problem ?
So the problem might be that the t-mount you have is not a match the camera. In astrophotograthy its common to use these to attach cameras to telescopes. they come in two parts , A is the bit that attaches to the scope and are mostly universal. B is a ring that fits in place of the lens in the camera. B is an adapter and matches your camera mount. Then you join A to B and you have a huge lens on your camera but you have to shot manual. Great fun for shots of the moon.