How to tune Lunt LS60T/60FDS/PT/B1200?
Posted 12 November 2012 - 04:40 PM
For example do I first focus then adjust the pressure tuner with the LS60F front etalon removed (to optimize proms), and then screw back on the front etalon to re-pressure tune/focus for surface contrast? If so is this process repeated for every viewing session? Seems like a lot of wear on the front etalon.
Do you back off the PT to equalize pressure for every session then screw back on...or only w/changes in altitude?
My add-on LS60F filter is on order.
Posted 12 November 2012 - 05:05 PM
Posted 12 November 2012 - 06:22 PM
Does that mean that when you re-focus on another area you have to take off the DS, re-focus, re-tune then add back on the DS and re-tune the top etalon again or do you somehow re-tune both together?
Posted 12 November 2012 - 11:41 PM
When I view I get the disk into focus, then I twist the PT down until the proms start to show, twist a little more till I feel like I reached that sweet spot and then tune the DS until surface detail hits the sweet spot. I don't feel like the DS does anything to the focus. It does make the entire disk darker when double stacked, but that is what it is. I might tweak the PT and DS slightly during a viewing session, but typically I see no real improvement after messing with it, so I probalby end up where I started. I asjust the focus a hair here or there. I'm typically using a Baader zoom, not quite parfocal so I need some slight adjustments when changing zoom.
Posted 13 November 2012 - 09:34 AM
Posted 13 November 2012 - 01:25 PM
Posted 13 November 2012 - 01:41 PM
Posted 13 November 2012 - 02:11 PM
Posted 13 November 2012 - 02:12 PM
I'm typically viewing between 25mm and 8mm because of my zoom ep and with the 1200 blocking filter I still get the entire disk into the EP. The higher the magnification the darker everything gets, so the proms stand out more at 25 or 16mm than at 8 but they are still there and look pretty sweet at 8mm.
I've never taken the DS off while looking at a prom to tell if I can see more of them or not. I'd assume it would be brighter and thus I'd maybe see a little more of “ghostly tips”, but I think seeing the surface detail and proms together is more impressive than a tiny tiny bit more of the proms. On Halloween there was a filament that wrapped around the edge that broke into a prominence that looked very cool. If I was single stacked, I don't know that I would have saw it as well as I did with the DS.
I'd also say the sweet spot of the PT seems much larger than the tilt tune. My sweet spot in the tilt tuned model was a quarter of the disk at most. Many people said my sweet spot was smaller than most. And I went forward with the PT retrofit from Lunt and felt the HA sweet spot was basically the entire disk afterwards.
When I was single stacked with the tilt tune I would move the altaz controls to move the sun through the sweet spot instead of moving the sweet spot across the sun. It was just easier than continuously adjusting the tilt wheel. The PT retrofit eliminated that completely for me, but I found myself moving the PT knob to switch between more surface detail and prominences a little. There was a point where I could see both and I'd usually leave it there, but adjusting the PT would give me slightly better views of one or the other, but it was all very slight. And lets face it proms are cooler than surface detail so I’d usually tweak in favor of the prom.
Once I bought the DS I really feel like I get the best of both worlds all the time. The PT gives me the proms and some surface detail, but as soon as I turn the DS wheel the surface detail just starts to pop out. Depending on what’s up there at the time, I almost get what I would call a 3D effect.
I think you’re going to be very happy with the DS. Not sure how much the DS60 improves the views over the 50, but I’m so happy with mine that I can’t imagine you’d be disappointed or struggle with yours.
Posted 13 November 2012 - 02:30 PM
Also, do you back the PT completely out to equalize the pressure to ambient conditions before every viewing session or basically leave it alone once adjusted?
Posted 13 November 2012 - 03:15 PM
Posted 13 November 2012 - 03:23 PM
I also notice the improvement when first screwing the PT in and then backing off. Also moving the image around to find the best sweet spot, also helps.
Posted 13 November 2012 - 03:51 PM
P.S. I always bino.
Posted 13 November 2012 - 08:42 PM
As far as equalizing the pressure, most of the time mine is mounted on the tripod in the dining room for quicker setup, and I don't unscrew the PT between viewing sessions at my home, but do readjust it once I take it outside. Not sure if I need to, I think it's just habit. You never quite know what's going on up there until you fiddle with stuff.
I also do some public outreach sessions that require me to travel 30 minutes away. Before I put it in the case I'll unscrew it, and give it one or two twists back on. I'm not changing elevation or anything like that, so it's probably not necessary, just my habit.
Bino's would be fun, but I really like my baader zoom for quickly zooming in and out. I'm about half your age, so my eyes are probably picking up more than yours at 8mm.
Posted 13 November 2012 - 11:39 PM
Posted 14 November 2012 - 12:48 AM
I don't screw the PT all the way in...just a full turn past the point of best view, then I back it out to the best view--usually a slightly different location.
We both probably have "age reduced" pupils, but I'm now 20/20 after cataract surgery and still struggle w/the 8mm's whether in bino or mono.
Posted 14 November 2012 - 12:26 PM
Posted 15 November 2012 - 09:57 AM
Posted 15 November 2012 - 12:17 PM
Posted 15 November 2012 - 03:35 PM
Posted 15 November 2012 - 09:42 PM