Another Lunt 60THa Tilt Tune Question

[Sumpy]

As some of you may remember, I purchased my Lunt 60THa used on eBay a bit over a month ago, and it was my first solar telescope. As such, I wasn't sure at the time exactly how the etalon worked and what I should expect to see. Since then I've learned quite a bit from the kind and knowledgeable folks in this forum, and now I know that my used telescope seems to be producing images typical of a Lunt 60.

My question is around the tilt tuning specifically. I'm in east Tennessee, at an altitude of approximately 1519 feet (463 meters) above sea level. I know that Lunt tunes these at around 2500 feet altitude to leave wiggle room on either side of 'on band' for elevation changes. However, my telescope is 'on band' with zero tilt - none at all. The tuning wheel is all the way clockwise (from the rear) with the tilt mechanism disengaged, and any tuning to the left ends up pushing me more towards the featureless 'white light' type view. I would have thought I should have more room to go clockwise, since I'm still over 1500' above sea level.

While this isn't really a problem now since I do appear to be on-band at my elevation, will this become a problem if I find myself at sea level? Is temperature something that maybe plays a role in this for a tilt tuned etalon or is that just applicable to the pressure tuned variety? I may be worrying too much about something that isn't important, but being so new to this I'm just not sure. It does makes me wonder if I am truly on band, or would the contrast be even better if I had more travel to tune in the clockwise direction?

Thanks!

[marktownley]

Hiya Brian.

This is the scope you've been posting your full disks from?

Mark

[robert]

Atmospheric pressure changes will alter the setting. Your images look very well tuned to me and due to the lack of tilt they are very even across the disk. If you have much tilt you get a band which is well tuned with bands either side that are less well tuned.
Looks good to me just now anyway
Robert

[Sumpy]

Hi, gentlemen - I greatly appreciate your input on this.

Yes, this is the telescope I've been using for my full disk photos, and as best as I can tell I do think they appear to be on-band in my (admittedly novice) opinion. I was just wondering if this was odd that I basically don't tune my Lunt at all, as it is apparently already tuned as good as it gets for my elevation at zero tilt. It led me to wonder what that would mean for a camping trip at sea level, or if perhaps maybe I'm still not optimally tuned but don't have the adjustment range to know for sure. As mentioned, I also realize I may be worrying over nothing.

If it helps, below is an image below of a full disk with no processing at all. This was just stacked in AS!3 with top 15% of frames, with nothing else being done.

unprocessed-disk.jpg (764.61 KiB) Viewed 1447 times

[robert]

I got a pressure tuned ls60 so that I could avoid tilting for full dusks. This worked but later I decided to get a 60mm Lunt double stack etalon which is tilt tuned to do DS full disks. I was gambling and hoping to get one with minimal tilt and was lucky. It goes onto the pressure tuned scope with no adjustment needed. I am at 100m altitude and I never need to adjust it. The two etalons work together easily and give an even disk, which was the hope and aim.
I think you may have been lucky.
Robert

[Sumpy]

I got a pressure tuned ls60 so that I could avoid tilting for full dusks. This worked but later I decided to get a 60mm Lunt double stack etalon which is tilt tuned to do DS full disks. I was gambling and hoping to get one with minimal tilt and was lucky. It goes onto the pressure tuned scope with no adjustment needed. I am at 100m altitude and I never need to adjust it. The two etalons work together easily and give an even disk, which was the hope and aim.
I think you may have been lucky.
Robert

Thank you, Robert - this is a great data point to have! At least now I know I'm not the only one out there with no tilt required on a Lunt etalon. I did notice early on I didn't have any banding of the solar disk as long as I kept it framed in the sweet spot, and this has made processing fairly routine without much fiddling. Needless to say I was very thankful that my sweet spot does seem to cover the entire disk evenly.

[marktownley]

I think it is spot on Brian

[Sumpy]

I think it is spot on Brian

Thank you, Mark! It sounds like I should stop worrying now and just enjoy my telescope.