Hello CNers,
I decided to aquire another NVD after finding out that L3 Harris has discontinued the comercial sale of Photocathode tubes to the general public. I had planned on getting a second device for Prime Focus latter on this year but this unfortunate news from L3 Harris, it became a now or never thing. It is better to have two devices anyway. Through one of our gratious members here on CN, did some homework and located L3 Harris, Super Gain tubes with excellent specs and PMed me the link to Night Hawk Vision Systems, I procured one. Not wanting two Afocal devices, I contacted AB Night Vision about their RVM 14-C housings and they don't sell their products to individuals but they informed me HCC Tactical, was do receive a shippment of these housings in about a week or so. I contacted HCC Tactical, and ordered a RVM 14-C housing. Rebbecah, at HCC Tactical was very nice and efficient and ordering was smooth and seamless. I asked to talk to a tech and was turned over to Mike, the Question was "If I sent my device to you, how much would a conversion cost?" I have watched a number of YouTube Videos and the conversion seems simple enough but some times money can be well spent on someone who has lots of experience like building NVD's for a living and the cost was not that much, so I went that route and sent off one of my devices and received the converted device back last Friday. It was about a two week turn around.
Friday night After getting home from work, I set up my TEC 140 and anxiously waited for nightfall. I plugged the device into the diagonal and turned it on and adjusted the focuser but I could not bring the device into focus no matter what. I sat back in the Starbound chair and dissapointment started to set in then I was hit with a revelation I popped my self in the fore head " You big dummy you need to adjust the Diopter" this was the first and only problem that I experienced with the NVD. My Seeing was good but the transparency was very poor Friday night to really test out the NVD, so I discontinued the session. Fortunately Saterday night was about as good as it gets and I had nearly an all nighter. When ever possable my first target will be M42, probably because M42 is always so awesome. Here are the differences that I noticed between the PVS14 in afocal and RVM in primary focus. The Image scale through the RVM device is as expected, very simular to having my PVS 14 attached to my 26 Nager and brighter. However, the Image is inverted with the RVM device and this caused a little bit of a problem with my muscle memory at times when slewing the scope. There is a good bit less vignetting and alot less optical distortion of stars towards the visual stop with the RVM device. I've never found this to be much of a issue with the PVS14. I guess that I have learned to ignore these distortions, just like ignoring a little scintillation, it is the nature of the beast. However I found this attribute very welcoming. The RVM device is totally awesome on Galaxies and Globulars and I could make out more Galactic and Globular detail with the RVM device than I could with the PVS 14 attached to my 26 Nagler and that prospect is golden, however in general the PVS 14 is still better on larger dim and defuse nebulae at least in the scope arrangement that I was using except M42. When I have another night I will try the RVM device with my Apertura CarbonStar 150 Newt and see how a short focal length faster scope changes the game. I wished that I still had my Discovery Dob for the Galaxies but unfortunately I'm Dob free for the time and waiting for my New Moon Dob to show up. One game changer that the prime focus RVM device beats the tar out of a PVS 14 is when it comes to using a night vision device on a Newt, I won't miss the reddiculously long visual stack that a PVS14 needs to get things to work. Also the visual stack for Prime Focus is also very light, so you will not have balancing nor focuser strength issues. The good thing is when it comes to the light filters. Both devices like the same ones, a 2.5nm Ha narrowband and the 685nm IR longpass filters still worked the best. Now that I have a prime focus device, I need to aquire the adaptors for a fast wide angle camera lens. I fully understand now what many have been preaching here on this forum between primary focus and afocal devices. The prime focus devices are the way to go because you can use these device in either focal arrangement by simply screwing in the PVS 14 objective lens for Afocal or using an adapter to use it in a diagonal for Primary focus. Plus other applications for handheld and camera work. However, I find it nice to have two separate devices. If for nothing else, in case one goes bad.
HAPPY SKIES AND KEEP LOOKING UP Jethro
Edited by Jethro7, 23 March 2025 - 08:54 PM.
