I have been trying to image the night side of Venus, which is a very difficult challenge. What is the idea here? Venus' night side, is of course, the unilluminated side. You are probably wondering what is the point in trying to image the night side of a planet that has an atmosphere that is opaque in visible light and is nearly 100x thicker than the Earth's. Well, if you can believe it, it has been shown that the heat signature or glow of Venus' surface features can be detected on the nightside of the planet if the right IR wavelength is chosen. The best wavelength is around 1000 to 1050nm. 

The ghost reflections of the hugely bright crescent are a real problem and can wipe out detail on the nightside. Experimentation by others, has shown that the Player One Uranus-C, a colour camera, has great sensitivity at the IR wavelengths we are interested in, but does not suffer too badly from spurious reflections. 

My initial runs with the Player One Uranus-C using the combination of the Pixelteq 1030nm and 985nm filters, giving a composite wavelength range from 1005 to 1013nm (see Revision B), showed some promise when used at Prime Focus, but the signal was marginal and there was a bright reflection from the crescent impinging on the darkside of Venus. A couple of fellow planetary imagers based in Rubyvale, QLD, Australia Anthony Wesley and Phil Miles, have had really good success at previous apparitions using Phil's 0.5m diameter reflector. They have also detected surface detail with the camera and filter set I am using. I discussed the differences between my arrangement and theirs with Anthony and he suggested that, given they have twice the light gathering area and half the focal length, their signal is something like 8x what I was getting. That is also consistent with the higher exposure time and gain that I was having to use. Reducing the focal length is an obvious way to get more signal and it ought to have the benefit of displacing the reflections further away from the nightside area we are interested in. I had a Celestron 0.7X reducer but after a trial it was clear that it has limited transmissivity at the IR wavelengths we are interested in. Another fellow imager, Peter Tickner, based in the UK, has shown that the Meade f/6.3 reducer has a 90% transmissivity and his Atik f/5 focal length reducer does even better. 
I have ordered the Meade reducer, however, my local supplier Bintel has their own 0.5X focal length reducer in a 1.25" format. It was very inexpensive and in stock so I sourced that. I tried that last evening with relatively pleasing results. The unit clearly transmits well in IR and halving the focal length should have given me 4x the signal, of course, with an image scale penalty. This gets me much closer to Anthony and Phil's light gathering power. It was pretty clear from the outset that the night side signal was much stronger than before. Further the reflection I had been dealing with previously was moved away from the nightside to give me relatively clean signal.

For the first 15 min run with a midpoint time of 17:56, I ran with an exposure time of 250ms and a gain of 440. For the 2nd 15 min run with a midpoint time of 18:13, I ran with an exposure time of 250ms and a gain of 516. After processing with Autostakkert and RegiStax, there appeared to be decent signal in both runs, so I combined them.
Pleasingly the patterns observed are similar to those I saw in Anthony and Phil's images of the same evening and I include a comparison with the WinJUPOS graphic , which shows a reasonably good correlation. The original image is shown as Revision C.
Certainly the results are encouraging for the morning apparition in September and I think I now have a combination that I can work with.