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Sunspot monster!


Ganymede12

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That is a big sunspot! Must be naked eye (with filter)...

I would say that your focus is off - also the focus seems to be worse on the right than the left - this would lead me to believe that the camera was not square with the scope. Exposure seems pretty good, so probably just focus to work on.

If you were talking pictures by holding the camera to the eyepiece then try something like http://www.firstlightoptics.com/adaptors/baader-microstage-clickstop-digital-camera-adapter.html this will enable you to make sure that the camera is square and does help massively in getting images.

Cheers

Ant

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I think you've done well to get these. I could never get on with afocal pictures. The sunspot group is naked eye visible, just about. I could see it when checking my Baader film filter.

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Thanks for posting Ant :icon_salut: it encouraged me to get my solar scope out for the break in clouds just before the sun set behind the house opposite - and it was well worth it!

Helen

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It was Ganymede that posted not me - I only replied :)

Afocal isn't that hard, but it is quite hard hand held. My animation of the first Venus Transit was taken afocaly but I used the DigiT sytem. You can get some cracking results just by holding up the camera to the EP.

Ant

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It was Ganymede that posted not me - I only replied :)

Afocal isn't that hard, but it is quite hard hand held. My animation of the first Venus Transit was taken afocaly but I used the DigiT sytem. You can get some cracking results just by holding up the camera to the EP.

Ant

Ganymede is also called Ant, Ant :grin:

Helen

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Focus is the key Ant.

I'm trying to remember back... Your using and ep in the scope and the camera has a lens...

From memory I used the maximum zoom the camera had - this got rid of the circle in the middle of the shot and enabled me to fill the camera chip with sun. I cannot for the life of me remember if the camera I had had auto focus only or if it could be turned to manual.

Assuming that the camera is auto focus only, try placing the sunspots in the middle of the FOV, then let the camera auto focus do it's stuff, and then use the scope focus mechanism to fine tune. With any luck the camera auto focus will allow you to do this.

Focus is one of the few things that cannot be corrected in post processing, it's one of the most over looked things in imaging - one that I too have rushed on a few occasions and regretted it later.

Cheers

Ant

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Focus is hard to get right Ant, but if you take your time to get it spot on your results will be so much better. The other thing to watch for is camera shake as you press the button - if you've got a delay feature then try that too to see if it helps.

Helen

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You can also get a remote shutter release for compact cameras. It fixes to the camera and presses the shutter button using a squeezy bulb or something. Can't remember where I saw it. but if you have problems with camera shake when pressing the shutter release it might help.

James

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My camera has a timer function so I have been using that to try and keep it still. Unfortunately the weather was against me a bit and the wind was threatening to through my kit half way across the garden!

Today I was lucky enough to get a second chance! I will post the pictures soon!

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I'm not sure what the problem might be to be honest. Some of it is just down to practice and getting a "feel" for what's going on. Could be worth posting in the hints and tips section asking if anyone has any to offer for afocal imaging with compact cameras. I can't see anything there at the moment. Have a hunt on the web to see if you can find any useful information too. You might find that someone has some clever idea or other that makes things easier. If you or someone in your family has a phone camera or a different compact camera, perhaps have a try with that, too. Comparing results might throw up some ideas. Above all, be patient. Imaging solar system objects is pretty easy, but imaging them *well* is a different kettle of fish. It takes time and practice. You should see the hours and hours worth of data that I've binned because when I looked at it in the cold hard light of day, it just wasn't good enough. Try to do a little better each time and learn from when you get it wrong and you will get there in the end.

James

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It might be worth pointing out that because of the method used to take the photos, the images are effectively cropped, the circle is not the perimeter of the Sun but the field of view so the sunspots aren't quite as large relative to the Sun's diameter as it might appear. Good results though on a difficult subject by these means. :smiley:

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The eye is extremely good at focusing images that are actually slightly out of focus. The CCD obviously won't do that.

You are getting close, Ant. So what I would do next time is....

1. Setup as normal

2. get as close as you can to correct focus with your eye.

3. Then twist the focuser slightly in one direction (remember which way)

4. Take and image and then zoom in on the screen and see what you think.

5. Turn the focuser the opposite way - very slightly - take another image and review.

6. Repeat till you reach the sweat spot, in actual fact you'll probably go past the sweat spot and out the other side - but that will be fairly obvious, in that case you'll have to start going the other way a little.

Once you get the best you can - mark the focuser tube - I use a pencil on the drawer tube. This means that next time I set up I have to just make very fine adjustments and can be imaging quite quickly.

I know that this might sound like a right faff. But it does work. If it takes you 30 minutes or an hour to get that sweat spot - it'll be worth it.

Your exposure times already look OK.

Good luck Ant,

Ant

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