I have the Vixen Polarie. I had an O-GPS1 for a time, but sold it. I now have the AstroTrack built into the K-3ii. The biggest differences are:
No annoying calibration necessary with the Polarie, but it must be polar aligned. (I built an adjustable wedge for the latitude part of the equation, so if your tripod is level and the wedge angle correct, the only thing you need to dial in is the azimuth alignment.) https://flic.kr/p/pVVUTv Both systems will face limitations at longer focal lengths, but you can do a lot with 200mm or less. This was taken with a 90mm Tokina AT-X macro on the jankity set-up above. https://flic.kr/p/qzf4Xi The O-GPS will track during an exposure, but the camera will need to be repositioned as the earth’s rotation moves it out of frame. The Polarie will track the object whether you are taking exposures or not (meaning you can use an intervalometer to take multiple exposures (for later stacking, for example) I think the biggest problem with my current Polarie set-up is flex. Even with a high quality ball head, it can be frustrating to think you have your object framed properly, tighten the bullhead down, let go, and find your object is no longer framed as you like. This problem gets greater the more weight you try to hang of of it. Both solutions are more for wide field astrophotography. But nice things can be done with the O-GPS and the DA* 200mm f2.8 as this French Pentaxian shows: http://poirierstephane.free.fr/photos/index.php?/category/132 However, it is worth pointing out that the same lens on a polar aligned Polarie could achieve the same results. Hope this helps. Darren Addy Kearney, NE On Fri, Jun 8, 2018 at 3:15 PM luiz felipe <luiz.fel...@techmit.com.br> wrote: > pretty much divided between the Vixen Polarie and the O-GPS 1. just > because if I get to use a small newtonian reflex, the camera will be > pointed at 90 degrees from the subject, and I don't think de astro > function of the O-GPS 1 can handle that. > > the Vixen Polarie is small, and seems able to handle both the APS > Pentaxes and a small reflex telescope - and as long as it's properly > aligned, the pics should be ok. > > as far as money goes, it's one OR the other, and that's why I'm looking > for advice. building a barn door star tracker is the third option, but > I'm not really with time to make a proper unit. toughts? ideas? > > thanks!!! > > -- > luiz felipe > luiz.felipe at luizfelipe.fot.br > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > -- “The Earth is Art, The Photographer is only a Witness ” ― Yann Arthus-Bertrand, Earth from Above -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
