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Solar imaging need help advice


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Hi I've been trying to get 'a photo of the sun' that's all but still failing and I don't know why... Its possibly focusing as there are no sunspots to help... Should I be able to see any detail visually?..... My gear is a f5 [5 Inch] 600mm Newtonian stopped down using the opening in the end cap, a solar film white light filter, a Baader continuum filter, canon 1100d using EOS movie record to make avi. And APT in planetary mode to take 1000 frames which I've tried stacking in Autostakert. No detail whatsoever just a coloured disc.. I also tried my webcam and Sharpcap but could not find any focus at all..I took the shots early morning..... I know solar is a whole speciality but Where am I going wrong?  Do I need more filters? Should I  Focus on a star then wait for a sunny day? Should I give up on solar?  I am a newbie to astrophotography. 

Edited by OdpSteviesteve
Forgot something
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Problem number one is that there is nothing to see. The second is that you mention that all you can see is an orange disc which means you have too small an image to see detail.  Posting what you have image wise would help with the advice you seek.

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You need to keep trying!  Solar is not that easy at the moment due to there being no spots to help you - they make things much easier!!  However all is not lost.  Firstly, rather than trying to get an avi go for single shots.  With your set-up the whole disk should be visible.  Load canon utilities if you havn't already done so (this allows control of the camera from your computer (or use APT if you prefer!).  Open live view and find the Sun then cut the exposure time down until the solar disc is very dim in live view - if in doubt use the lowest exposures you can (I think it is 1/3200 and 1/4000sec? - I use an 1100D too but can't remember!). Then try focussing on the edge of the disc.  When you are happy take a picture and have a look at it full size on the screen.  If it is in focus you should see a slightly mottled solar surface and maybe one or two tiny black "pores" if there are any on view.  Have a good play changing the focus slightly between shots.  Eventually you will get it right.

Once you have got focus and an image that you can see some slight surface detail then centre the Sun in the field of view and fire off about 60-100 (or more) shots - Canon utilities will let you do this if you hold the "take picture button" down.  I usually listen to the camera clicking away and count about 10 shots at a time.  If you don't stop after about 10 the computer won't be able to download the images quickly enough to continue.

Check you images and hopefully you will have a decent set you can then process.  First you will need PIPP (freeware) which will centre and crop your images.  Then stacking software.  For full disc DSLR images I use registax5 HERE  (This is not the latest version but is by far the best for DSLR solar image stacking).  Use a big align box (512) and put it over the edge of the disc.  Hopefully you will get a stack - this can be tricky with no spots!  If there are spots pick one and use a box of 256 centered on the spot).

Once you have your stack you can use something like ImPPG (freeware) to sharpen the image (use Lucy-Richardson deconvolution).  

This thread https://stargazerslounge.com/topic/153712-simple-white-light-solar-imaging/?hl=+simple%20+white%20+light%20+solar  gives you more detail of the technique.

Below is a single frame from a recent imaging session:

001.thumb.JPG.457a0da2e40b2d5f935e21488c4fd6ff.JPG 

Which should give you some idea of what to expect.

Below is the final image from a stack of 40 from 150 taken

195139779_4April2020SunJPEG.jpg.4bf107a4098a9d24cb82160b640bdfcf.jpg

 

Hope this helps you get going - it is a steep learning curve!

 

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Great. Thanks a lot. I hadn't considered that approach to getting focus I will try next session. I will also downgrade my registax. The picture is fabulous by the way. I got started in all this on the moon with a webcam without knowing how to use the mount properly. I corrected my knowledge only for the moon to effectively dissappear giving me nothing to practice on.. I used APT in planetary mode it takes frames at about 18fps with the 1100d. Though it seems only jpegs. I'll try APT and set a capture sequence of raw images next time after a focusing session! 

Sun Continuum jpg.jpg

sun 1000_sun_32_f335_quality_100%.jpg

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How do people get on with using a laptop in sunshine!? I perch mine in the back of my vwt5 stand under the tailgate but its still very difficult the screen is like a mirror. Probably one of the reasons I'm finding it difficult to focus. Along with lack of practical experience, the laptop battery only lasted 2 hours, another problem to be solved by ebay, dc dc boost 12v to 19v regulator on the way. 

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I have laptop in a box and wear black to avoid reflecting on the screen, an electronic focuser is a boon as you can hide in the dark and focus, nothing fancy a cheap DC motor version with hand controller is fine.

Focusing on the Sun is harder than DSOs as the Sun is continually altering in real time and also bubbling away in the seeing.

Dave

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Thanks for the tips Dave, I ordered an anti glare screen cover and might try  lining a plastic storage box with black velvet to enhance contrast , and wear a black t shirt! I'll have a go at making a focuser, maybe a stepper motor and controller with some sort of gearbox might work. I appreciate the variable nature of seeing and focus, a brief glimpse of sharpness is what we are looking for? I have checked collimation with a Cheshire 

Edited by OdpSteviesteve
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I use a Ikea fold up file box.

You can get a fancy thermal cover, when I can find it or a blanket or towel works but gets a bit warm underneath.

 

Remember the sunblock as well, I had a leg sticking out from the cover yesterday and my foot got a bit red.

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Ordered 12v motor geared to 1/2 rpm, 12v variable /reversable speed controller and a flexible shaft coupling, Should have remote auto focus sorted by the next session £25. Astrobiscuit is my inspiration!  Do I need to spend money saved on a Ha filter? 

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Glad to see you are getting sorted.  However I am concerned about you "spending money on an Ha filter"?  Are you expecting to take Ha photo's of the Sun?  If you are then this is NOT the kit you need.  The regular Ha filters are for deep sky pictures of nebulae etc and are totally unsuitable for imaging the Sun.  If you want to do Solar Ha imaging you will need a specialist Ha telescope or eyepiece system like a "Quark".  Either of these these are extremely expensive bits of kit!  Prices start at about £1000 and rapidly go up from there!  Be warned Ha solar astrophotography is very expensive.

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On 22/05/2020 at 12:18, OdpSteviesteve said:

How do people get on with using a laptop in sunshine!? I perch mine in the back of my vwt5 stand under the tailgate but its still very difficult the screen is like a mirror. Probably one of the reasons I'm finding it difficult to focus. Along with lack of practical experience, the laptop battery only lasted 2 hours, another problem to be solved by ebay, dc dc boost 12v to 19v regulator on the way. 

Honestly mate, this is more or less the same set up when I started, F5 newtonian and a Canon 1000D. I use a large cardboard box and have painted it back inside, so much easier to see the screen, its low tech but works!

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  • 2 months later...

Thanks bizbilder I'll save my money... Sorted auto focus on my 620mm f5 Newtonian, sorted anti glare screen on laptop, using solar film filter and baader continuum filter, the green one, out this weekend, solar and hopefully some eaa. Longer scope on way and also a ZWO asi 224 mc on way to replace my webcam.. Scope may be unnecessary as I have 2x and 3x barlows, but 1200mm 6" for £80 is OK. 

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