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Buzzard75    55

First time observing the sun directly. I have a 12" dob, 1500mm FL. I have an Orion deluxe off-axis safety film solar filter and I'm using a 28mm eye piece. I finally got it all lined up and all I see is a white blob. dialing the focuser in and out appears to do absolutely nothing. Is the filter not a good one? Do I need a longer focal length eyepiece? Do I need a shorter focal length eyepiece? Help! Thanks in advance!

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Floater    2,134

Well there's not much to see in white light at present, I'm afraid.

But I worry about 'blob'. You should get a crisp disc but, as above, not much on the disc.

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ronin    3,693

With a white light film filter then you tend to get a fairly plain white disk, and it is plain(er) as there are no significant sun spots to focus in on. Would say that you get no granularity with a white light filter but last time I said it people told me they saw lots of granualrity, so maybe my eyes.

Sort of unfortunate but what you are seeing sounds about right at this time, the Sun is a bit of a blob as the edges will not be crisp.

Will say not confident about the set up you have, 12" is a lot of light to reduce to a reasonable level from the sun, and not sure what an off axis filter is like either. Have you a UV/IR cut filter in the path.

Assuming it is all OK you will have to wait until some sort of sun spot appears on the sun then you will have something to 1) see and 2) focus on better. Then with an object to fine tune the focus you may get to see more. Apparently a green filter of (I think) 540nm helps sunspot detail.

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Stu    14,422

In theory the kit you have, including the eyepiece should be fine. It should show an approx 1 degree field which is about double the solar disk size i.e. Plenty to fit it in, at x53 which is ideal.

Can you bring the image to focus and see a white disk (rather than a blob)?

As said, the sun is quiet currently so at first glance you may see nothing although there is always granularity there and normally some faculae at least towards the limb somewhere.

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John    17,048

When you say a white blob, was it a clearly defined circle ?

There is not much activity on the Sun at the moment so it is possible that all you will see is a white circle of light.

Your filter provides a 4" off-axis aperture and uses the Baader Solar Film. It's good stuff and does show a white solar disk. With the 28mm eyepiece (a 2" one I think ?) you will be seeing a true field of view of around 1 degree and the Suns disk will take up about half of this.

Edit: Stu has posted practically identical advice and just before I pressed "send" ! :smiley:

 

Edited by John
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cletrac1922    47

Try using with plastic cover on, and removing small disc cover

Put Baader AstroSolar Safety Film underside of small disc, and greatly reduces amount of light coming into the dob

Have attached a pic of 80% solar eclipse taken a couple of years ago Goldcoast foreshore using this method

Pic was taken holding Samsung Galaxy 5 to eyepiece

Solar Eclipse.jpg

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Buzzard75    55

Maybe blob was the wrong word. Yes, I see a disc, but no detail at all. I was expecting to see more detail like the granularity mentioned by others. Maybe I was expecting to see the wrong thing and all I'm going to see is larger spots, but it's just not very active at this time. I also wasn't even sure if I was seeing the entire disc of the sun using an off-axis filter, or just a portion of it, hence why it was a perfect disc with no detail. As I said, this is the first time I'm observing the sun directly myself. The only other time I've observed it previously was through a pin hole camera projecting the image of an eclipse when I was a kid, and one other time at the Griffith Observatory in LA several years ago. Maybe I just need to understand what I should actually expect to see.

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celestron8g8    81

When I observe the sun I use my C8 SCT with a Baader  Solar Filter and yes it's hard to focus . I think someone mentioned about watching the edge which is exactly what I have to do is watch the edge only and focus for a sharp edge . Since hardly no sunspots are seen right now a solid white disc will be very hard to see . Once a nice sunspot comes around it will be much easier to focus on .

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Stu    14,422
4 hours ago, cletrac1922 said:

Try using with plastic cover on, and removing small disc cover

Put Baader AstroSolar Safety Film underside of small disc, and greatly reduces amount of light coming into the dob

Buzzard already has a sub aperture filter which should be good.

Nice picture of a great event :) 

@Buzzard75, take a look at this post, there is an image in it of the view through a dob with solar filter. It shows a well defined disk but with no detail. That's likely what you will see at the moment as there is not much going on. On days of good seeing you should, if you get the focus right, be able to see granulation as a kind of mottled effect across the disk, stronger in the centre. You may also see networks of brighter lines called faculae towards the limb. Focus is very important so get that as good as you can.

 

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Floater    2,134
9 hours ago, ronin said:

... sounds about right at this time, the Sun is a bit of a blob as the edges will not be crisp.

As per the thread title I, too, need some help here. Why do you state that, ronin? Is it with reference to the size of scope Buzzard75 is using? Because using Baader film on my TV76 the limb is razor sharp and the image couldn't be described as a blob by any stretch of imagination.

In management speak we have a disconnect; in street speak, wazzup? 🤔🤔

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Buzzard75    55

Thanks for all the responses. Definitely educational. I think this is a lesson in managing expectations for me. I had expected to see something different with more detail and didn't understand why the image didn't match those expectations. I automatically assumed there was something wrong with my gear or my setup. I'll keep my eye on the solar activity trackers and try again when there's a bit more activity. I may try an extender on my focuser as well. It seemed the image was getting sharper as I was dialing it out and I thought I was starting to see some of those faculae as mentioned, but I felt like it wasn't quite there even at the full extent. I didn't notice a dramatic difference between the focuser all the way in and all the way out. It was a very slight, almost unnoticeable difference. I do have an extender that adds about another inch and a half to the focuser. I'll add that and I'll also try the trick of using the limb to focus.

One other question I had is regarding the brightness. Any recommendations for dialing this down some without affecting the image too much? Even with the solar film it's still a fairly bright image and somewhat uncomfortable to look at for more than a second or two. Yes, I'm staring at the sun, but I would have expected a bit less light transmission with a bit more contrast considering I'm looking through a metalized film. Again, this just may be me needing to manage my expectations. I do have variable polarizing filter for the eyepiece for lunar observations. I believe it goes from 1-40% transmission. Would this help at all or should I not bother? Should I try a different type of filter, i.e. glass, to be able to see what I expect to see?

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celestron8g8    81

With a white light filter the only thing you can see are the edges and any sunspots that are visible . You will not see any activity nor will you see and Solar Flares . For anything else you need the special filter or scope that will allow the details to shine . Can get very expensive also . As far as the comfort watching I would just advise putting a towel or something dark over your head to coverup outside light while viewing but the comfort I would just suggest don't look at the sun too long even tho you have the filter . If things start bothering you a lot then you might inspect your filter for any pin-holes or defects and if you find some stop using that filter . You can check by holding the filter at arms length between you and the sun . If you see anything not right stop using it .

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Floater    2,134

A solar continuum filter will help if the brightness is too much for you. Just be aware the image will then be green - some folks don't get along with that.

Stick with it. Solar viewing can be very rewarding. 🌝

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celestron8g8    81

I wonder if you use a moon filter on the EP if that would help without degrading the sun image . If I think about that next time I view the sun I'll try mine and see if it helps . 

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Azelfafage    15

I second Spaceweather. From a psychological viewpoint I wouldn't really recommend anyone looking at it prior to a solar observing session, but then if you're having difficulties, at least it'll give you an idea of things will be like when you put your eye to the scope. There are a couple of small spots on the disc as I type this.

What's your budget and equipment storage situation? If you're getting really keen on solar observing, you'd be better off with a small refractor.

Good luck :happy6:

A.

 

 

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JOC    1,200

Hi Buzzard75, I'm also just starting to take an odd look at the sun, on my first day I also got a featureless circle, prompting someone to note that in terms of activity the very day I had chosen for my first look was about as quiet as the sun had been for 2 years!  (Now that's what you call timing!).  My filter gives me an orange circle and there is a picture of my first telescope viewed sun on page 1 of my thread here:

You will see how featureless that disc in the sky can be!

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