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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Convert with questions on set up (1 Viewer)

Skywatcher arrived today, the MaxDSLR arrived yesterday. Couldnt wait to play with it. However, I found the MaxDSLR does not screw onto the eyepiece holder, I have a t ring which screws on ok. I tried the setup with this and was pleased that at 800 ISO and a target at over 25 meters shutter speeds can still be quite high and AF confim light works ok(had a widow of sunshine).

Measured this distance (with my sigma 150-500) and found minimum focus distance to be 25.1 meters with camera attached to scope with just a Tring.

I also have a Opticron push fit adapter with Tring thread so tried this, compression ring was too small for secure attachment but I held it on without, found a target that I could focus on at minimum distance and measured this, minimum distance was now at 11.2 meters.

I then measured the extra 'spacing' the push fit gave over just a Tring, this was about 22.5mm. I then calculated that for each mm spacing, minimum focus would be reduced by approximately .6 meters. So when those ext tubes arrive I could (in theory) get minimum focus distance of 7.1 meters with the 30mm tube.

Unless of course my theory is incorrect.

Also, a quick question: is this the correct formula tocalculate an eyepiece magnifictaion factor:

Scope focal length divided by eyepiece focalength, ie: 600mm/40mm = X15 mag
 
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Heres a quick shot, Dog asleep across the street, 80 yards, 2nd photo 100% crop
 

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