help needed with Lunt 60mm PT DS im new to this

[astro1949]

when i use my lunt 60 PT SS the sun "POPS" with detail !
when i DS with the 50mm TT i see very little detail (?)
the image is very dim -- its very hard to focus -- only 3/4 of the full disk is in-focus around the edge.

i try to use a Celstron Neximage 5MP camera -- problem is exposure time.
ss i can get about 100 times faster than DS.....

any suggestions

i have been using telescopes since 1960 ( Criterion 6" f/8---still have it!)
i have a meade 14" lx200 GPS SV-80 and SV - 102 so I am baffled that i can not tune and focus the Lunt........

thanks,
bob

upsate NY

[rxdeath]

well ds will certainly be dimmer than ss, that is normal and expected, but it shouldn't be enough darker that it's a problem.


i'll skip asking all the questions since you sound experienced and maybe just recommend you post some pictures of the views, probably not me, but some on here can see a picture and tell what's up with your scope better than from a description.

[astro1949]

thanks, i am trying to get decent pics of ss vs ds but the clouds have been an issue every time i have the time to try it. I know a Picture is worth 1000 words.
just wondered if someone had come across this and it was a simple operator error.
i have been in contact with Lunt-- they sent me the "Blue" filter in the diaganol that is ( for some ) an issue ---mine was fine and it didnt help-- picture and exposure times will be comming next

[rxdeath]

yea, ds took me a while to sort out, but there's only 2 things so its not too hard to go through all the options 1/4 or 1/2 turn at a time. i definitely experienced some 'red ball' issues where i got no detail because of the current tuning, but fiddling got rid of it, and i never had focus issues with 1 vs the other, at least not more than normal. the distance between the 'front' and 'side' of the sun is ~610,000 miles (430,000 (sun radius) * sqrt2 (45/45/90 triangle ratio is x/x/sqrt2x) ) i don't think that it is treated as infinity point source, so the rays from the edge do not reach the scope at the same time the rays from the front do. i think this is why with bigger scopes the mosaic is king vs full disc because each panel can be focused, smaller aperture doesn't seem to show this problem as much.

experts please correct me if i'm off base here, it's likely much more complex.

i would ask your altitude because at high alt you sometimes just can't get enough air into the PT, but you say single stack looks great so i don't think that's the issue.

if i had to guess i would say it's most likely something in the tilt tuned ds module, we had another individual on here who was getting horrible bandpass for some reason with a coronado setup....if it works solid in ss mode, then i would start pointing fingers at the ds50 end.

[astro1949]

sun ds0006 11-34-31.tiff

sun0029 11-04-33.tiff

sun0001 11-00-21.tiff

first is DS next two are single stack images

[rxdeath]

trying to help with picture upload, not sure if the site is having problems:


ss:

ds:

ds:

[rxdeath]

i'm wondering if the camera has the dynamic range needed to be good for solar imaging, but idk.

ds looks like crap
ss looks better, but not quite right


hopefully one of the gurus chime in, maybe let us know if this is a brand new setup or did you get it second hand, etc...

[Montana]

Mmmm don't upload Tif images, no one can view them, thanks rxdeath for the images The single stack looks OK, just need to remove the dust bunny and put the sun in the lower left corner to get a more even coverage.

I presume that you just screwed the double stack straight on following the first image and the view was like this? If that was the case something is seriously wrong with the double stack unit. The focus should be unchanged, the tuning might not be right but the focus is always the same. I would explain this to Lunt and show them the images as soon as possible as it is possible the etalon is decontacted and needs repair. The single stack unit looks fine.

Alexandra

[astro1949]

thanks,
i have sent these and others to Lunt.

i will press them to help me now that we know the blue filter ( taht had some issues in other scopes) was not an issue with my scope.

bob

[Marcello]

Hi Bob,
I have hours of experience with my Lunt 60 and the 50mm DS unit (that's the scope I used most in life indeed!) and I can only confirm you the words from Alexandra: adding the DS never affected focus. Exposure times yes of course, but never focus.
Hope you can solve the problem and enjoy that wonderful tool!

cheers
Marcello

[astro1949]

thank You !
i'M excited to see what a functioning DS can do

bob

[astro1949]

thanks for all the Help---
just so you all know i can focus a telescope -this is a shot of Jupiter at 16:06 in full sun
telescope is 102mm SV Planet killer Celstron Nextimage 5mp

i'll be very happy when Lunt gets back to me.

[GUS]

Are you actually focusing on the sun or one of the ghost images of it. The images you've shown look very similar to an image of a ghost, and probably explains the focusing issue.

[rxdeath]

ha, i mentioned the annoyance of ghosts with the tilt ds in our pms, but i never thought that could be the problem. from what i've seen here and experienced, lunt equipment is rarely just bunk and this being the problem would correspond to life in general: you make most of your own problems

my ghosts were (if the real sun image is in the center of a clock) in the direction of 2 and 8, the middle one is the real deal i'm pretty sure, i don't have it anymore so i can't check, but it will be obvious if you see all 3 which one is real. you should be able just to slew a little bit, another tell tale sign is that when you adjust the tilt tuner, the image will move. the 'real' sun will not move, ghosts will.

i don't see too many day shots of jupiter, looks pretty sharp considering i complain about a quarter moon ruining my photos...

**edit if you just screwed on the ds without moving anything as alexandra said, i'm pretty sure you would be on the 'real' sun, no ghosts in ss. if that's the case, i'd ship that puppy off to lunt. **

[astro1949]

i thought of Ghost --- when i tilt, the reflex images move across the field of view.
i turn the wheel about 3 or 4 1/8 turns ( or so) and the ghost are gone
i did try on of the others, but i had to slew the scope quite a bit from SS mode---just checking the dumb stuff

my operation the last few tries is to start SS -- focus--tune --screw DS on --

saga continues ====lunt got back to me 5 minutes ago ---they are sitting down tomorrow and going over all my info and pictures ( 15 or 20 i sent in since we started talking) and we will go from there.

i'm a Physicist,so i tend to over saturate with data, pics, and details....even if i have no idea what i'm doing !

this group is GREAT.....

bob

[astro1949]

tried again today Single stack - tune/focus --CAREFULLY added DS --
i also found if i rotate the DS unit -- the smeared image rotates....

these were taken with a Meade DSI III mono....

comments ?

[[whrudey]]

Hi Astro1949;

Some years ago before we could afford better imagers, I used the NextImage5 and, seldom obtained passable images. Have you considered using a different imaging device ? The ZWO series are very good and offer enough variety to meet all needs. Our NextImage5 is now in its box at the bottom of a drawer.

Just a thought ..

Bill

[Carbon60]

Hi,

I use a DS Lunt60 and what you describe definitely is not 'normal'. Setting up in SS mode and then adding the DS etalon does not change anything other than tuning (and brightness, of course), so I'm baffled as to what's going on in your case. You would know if it's a ghost image, or not, for sure when re-tuning the front etalon.

I hope Lunt can offer a solution.

Good luck.

Stu.

[pedro]

I would recommend using your scope without a second etalon first. My experience with DS is not great, I can always get better results with a single etalon. That said check out two FD images obtained about 2 years ago



LUNT60 + CORONADO SM60.

The single stack image looks better to me (and brighter)

[astro1949]

thanks Bill, stu and Pedro ---
hopefully LUNT will get back to me today -- i have been working with then for about 1 month...
bob

[astro1949]

My LS50F will arrive at Lunt thursday.
they think the Etalon is Decontacted....
im sure all will end well and I'll be using DS soon with success

thanks for all the posts and help.

[rxdeath]

they will sort you out as quickly as possible i'm sure. you'll be soooo happy when you get it back i still remember my first ds image, it looked like the sun needed a lint roller because of the additional detail, proms are so much darker

ps
pedro, that is the best detail and contrast i've ever seen a singlestack image have. i would have bet money it was a ds. do you have a capture file you'd be able to share with us for this great image?

[astro1949]

My DS filter was decontacted--must have happend in shipping to OPT or opt-to-me.........
i hope to get it next week. i'll try it asap and report.

[Montana]

That's great news that the problem has been identified, it means you are well on the way to fixing it

Alexandra

[astro1949]

so now I need a new CAMERA !!
ZWO (?)

[astro1949]

got the 50mm back today repaired, cleaned and ready to go......
some sun and clouds -- ds filter works.......

now i need a new camera

[rxdeath]

nice, glad it all worked out. the zwo camera are the best bang for the buck you can get nowadays in my opinion. many people on here use the 174 (more expensive, bigger chip) or the 120 (you can get this one for like 200$), buyt it won't do full disc natively so your full disc will be mosaics or you need a focal reducer. fyi, i hated the idea of mosaics when i was new, now i prefer it to full disc even though i have a chip than can do it, if i have time, i'll always go mosaic.

[Montana]

[astro1949]

looking at ZWO 174 and ( Maybe) 1600 cooled