First solar image in Ha

[durr]

This image was taken today on a Lunt LS60THaPT single stack, the double will come later. There were 1300 frames and stacked on registax 5.1 The telescope was mounted on a NEQ6 pro mount. Click image to enlarge.

[ATTACH]40281[/ATTACH]

[Peter Drew]

Nice image Steve. One in the eye for the "naysayers"

[durr]

Peter, I take no notice of what these so called experts tell me. I am expecting my double stack soon so hopefully I should get even better results. Have you thought anymore of a colour camera? I think I might try some colour stuff later on. Finding the sun on the screen and getting things just right is quite time consuming but once done you can quickly repeat the process. Best regards Steve

[Technobill]

Nicely Done Durr,you have to be happy with that.

Oooh I missed out on some controversy... what are the neighsayers or experts saying?

I have the LS60THA with a DS50 for double stacking.

All my images since January have been the standard scope without the double stack. I was finding it hard to tell the diff actually.

As you can see from your image the standard scope does an excellent job, so if you are on a budget this shows just want you can acheive without having to go to a DS.

On Sunday I decided to use the DS and the images are good also but its not a must have in my experience you have to look pretty hard to tell the diff (no expert here just someone with the scope and the DS).

Regards

Bill D

www.billd.net

[durr]

Bill, I would sooner take your advice than the so called experts who have obviously never looked through a decent Lunt. It’s a bit like the sports car analogy I only ever see them in my wing mirrors on the bike when I shoot past them, they just have a bemused look on their face. We were falling about laughing here in the east end. It’s interesting to note what you say about the double stack and yes you are right the single stack favours well against my mates double stack 40. Steve

[Merlin66]

I'm sure when you look carefully at your double stack images ( use f25-f30 if you can) you will definately see a marked improvement in the surface detail and textures. Tuning the DS is a PITA and takes a bit of time. In my case I usually set one etalon to give a crisp Ha image and then back it off, say to the LHS of the tuning...still on Ha but "just off" band. The second etalon is then tuned across the Ha until I find a position (on the RHS) where the intensity drops by around 50%. This means that the two transmission "bell curves" are overlaping and giving a resultant bandwidth of 50-60% of the individual etalons.

I can easily tell the difference in the tuning of a few degrees between the etalons.

For proms, they should be tuned together to give maximum intensity spot on the Ha. This gives the best views.

I have an article where the tuning of the etalon was calibrated against the doppler shift of the Ha line - this means you can image proms at different velocities - very interesting results!!!!

Keep up the good work - the more solar observers we have the better.

Ken

[NickH]

Nice image Steve. One in the eye for the "naysayers"

Left side is out of focus.. was that seeing in your wing mirrors?

If that's on a tracking mount it negates the possibility of it being image drift, and the edges are clearly showing out of focus/streaking, and as for being an expert, I let the images do the talking..

Now...for facts...

as for "naysaying" the B600 Lunts were largely astigmatic...fact. I know real "experts" who can also testify to the coatings on the etalons being a problem (which is why they changed them). They had a serious QC issue, which it looks like they have fixed. I am not dissing them, but when you think that their former EU distributor uses Solarscopes (dual SF70's ) and not Lunts, as quote "one is business one is real astronomy", you begin to wonder

It does look like they are getting much better, which is great for solar..

Cak since day one has been superb...finally (now that Coronado have beaten them on price), they seem to have delivered..

Why people get so touchy I don't know, I went through 4 shoddy PST's to get a good etalon, and when in the early days people told me about the astigmatism issue, I got it resolved...didn't take offence, just got it fixed...it's just a scope...

And I have tried 6 Lunts, 5 would go back, one was VERY good indeed... but had an etalon tuner that was literally slopping about, to the point that it was taped up to hold it in place. But, the view and images were terrific, and were pin sharp in focus all the way to the edge, unlike that image!

I hope it was seeing, I hope it's not astigmatism..

[durr]

Ken, can you send me a copy of the article I would be interested to read it. I think you said earlier that fine tuning was the secret and I believe that you are right. The Doppler tuning is a [removed word] to perfect but it is early days yet and thanks for the encouragement. NickyH more like me only using one screw to tighten the camera. Steve

[NickH]

It could also be Registax of course with alignment

Hope so..

[Merlin66]

I'm impressed with the speed of development of instruments for Ha observing. Not too many years ago it was almost impossible for the "average" amateur to view in solar Ha. Look at the situation now..

We have at least three or four good suppliers continually refining and upgrading their solar filters and prices continue to fall.

Like any development there will be quality issues, let's be honest, the F-P etalon is not exactly the easiest thing to manufacture.

I, like Nick, have gone through many PST's to find one that was "just right", but I have to say I had more success the the Solarmax filters and was lucky to find a good SM40 and later a couple of good SM60's.

I'm sure in the future that even better filters will become available...but at the moment lets just "hold hands in the traffic" and enjoy the luxury of being able to observe the sun in Ha.

The attached paper shows the resolution of the SM60 as measured at 0.64-0.68A and demonstates the doppler tuning.

( It was translated and uploaded to the Y! group astronomical_spectroscopy by Alex -many thanks!!)

Ken

Coronado%2060%20review.pdf

[durr]

[ATTACH]40293[/ATTACH]Nick, you maybe right with Registax I had some awful bits where dark images and light images were being displayed. Cast your beady eye over this and and let me know what you think. Best regards Steve.

[durr]

Thanks Ken and Nick.

[Technobill]

Hi Ken I would be interested in the article you mentioned as well.

Always nice to read stuff maybe find a hidden gem of info.

[Merlin66]

Guys,

copy of the paper posted with message #10 above.

Ken

[NickH]

Steve, thanks for the remarks on PM, no harm done and yup, we're still friends

Now...image

For a first light image it's superb, really well done. The bottom right and left are a bit out, but it could again be registax, try avistack as I think you'll find that much better (and it's pretty nippy now in V2)

I told you a bit of the back story as to why with Lunt, and like I say, I think now they are getting way way better...it's all good as Ken says, especially now with Coronado back in the game.. spoilt for choice

[russ]

Steve, that's a stunning image, especially the redo. Incredible surface detail.

I envy those with a Ha scope, regardless of brand. It certainly is a good time for Ha solar observation/imaging. It just needs to get a tad cheaper still.

[durr]

Thanks Nick, will try and get some images up later on while I have a week off work. I am now thinking about a zoom eyepiece and I do like the one you mentioned earlier and also Kens favourite. I think I have a budget of about £250 so I will start from there, these things are not cheap. Thanks for the comments Nick. Steve

[NickH]

And Steve, the focus is a fraction soft (I guess it's at around F8 ish native) which either is the focus was soft, or could be something else. Try it with a barlow or two in place (bump it to F25 or so) and see how the focus holds..

[durr]

Will do Nick, thats if we get any sunshine down here. Nick a quick question, how do you rate the cmax lenses and would they work well with the lunt? Steve

[NickH]

I had one cemax EP... only one...never bought another

read in to that what you will :-)

For visual, a good 9mm widefield EP is alll I ever use, when I do bother to actually look at the Sun rather than stick the Lumenera on it

[durr]

Thanks Nick just thought I would run that one by you. Steve

[NickH]

To be honest I am not an expert in EP's...:-)

I hear the Baader ones are excellent for solar and the Pentax.

I love televues for deep sky, but then they cost a fortune (Naglers and Ethos!)

[durr]

Nick, I have a friend with the new Baader who is coming round later so I will get chance to view, but I like the reviews of the Pentax. Steve

[Merlin66]

I got a set of the CeMax eyepieces with the SM60.....

They're as good as some of the early UO orthos I used to use, but IMHO nothing special....

I use either the Pentax Zoom or my trustly ol' TV plossls. The 10.4mm is a good compromise.

Ken

[durr]

The Tele view 10.4mm sounds good. Like Nick said earlier, I think I need one good eyepiece for viewing and the rest of the time will be imaging so this maybe the solution.