Friday, April 26, 2013

A photo of the sun from yesterday, Thursday mornings outing.

I woke up Thursday morning (yesterday) and went out for a ride and since it was clear in the morning I took my binocular telescope and solar filters with me.

I also took my canon EOS camera as well.

Grabbing something to keep me warm, I must be addicted to those Tim Horton hot chocolates, and I don't even get paid to mention those so many times on my blog. . . :)

Anyways, grabbing the hot chocolate, I decided to setup right on Fort Street in Trenton Michigan.

The sight was rather poor due to rising thermos coming off the streets and from all the traffic. I snapped a photo using my iPhone which did not turn out very well.

I USED A SAFE SOLAR FILTER - designed to safely view the SUN.
I used safe solar filters.  See more comments below, but didn't use a guard outside to block the sun that might be hitting the outside eyepiece.  I wasn't looking through the safe solar filter from a shaded location.

Glare from the sun can affect the view and the photos.  And we can see a reflection lens flare which is caused by glare in the photo below.

I decided to try to take a few photos with the Canon EOS and those were not very good as well.

I downloaded one of the photos to my iPad and saw that there was a big reflection glare by the bottom of the image.

The photo below was taken at 1/160th of a second, handheld.

I decided to tweak the shot a bit in Filterstorm and this was a simple Mellow Yellow filter setting I saved in Filterstorm, making the white disk image look yellow which is more pleasing to some viewers. I also sharpened the image a big bringing out the details of the sunspots a bit, but a zoom into the photo shows I may have over sharpened the image a bit.




It's interesting that many people think the sun is normally yellow when it's up in the sky. It's so bright we don't look at it directly. The sun will show different colors when briefly glancing at it due to the atmosphere of the earth absorbing different wavelengths, in effect becoming a filter.

WARNING: ONLY USE A SAFE FILTER DESIGNED TO LOOK AT THE SUN AND READ DIRECTIONS CAREFULLY.  When in doubt, don't look and save your eyesight.

Don't look at the sun directly or with a telescope or binoculars because you could go blind. Have an astronomer verify the correct filters for a telescope, or call one of the many telescope and astronomy dealers that are out there who are knowledgable and can sell you a special filter or solar observing system that can safely view the sun.

Companies like Daystar, Thousand Oak Optical, Lunt, Coronodo(Meade), and Baader planetarium, sell solar telescopes of safe filters.

There are many ways that are UNSAFE and dangerous which people think are safe. This includes homemade filters from mylar ballons, and almost every type of welding glass sold. These are NOT designed to look at the sun and are not safe. I had an old astronomer who had a lot of knowledge tell me he was using number ten or twelve welding glass to view the sun, and that is NOT the safe rated glass to view the sun with.

There is only one kind of welders glass that is safe to view the sun through and that is only for naked eye observing, not using powered observing through a telescope. Because that glass is rare, your better off no using any welders glass and avoid using any of them.

The only safe welders glass is the old number 14 green glass welders glass, or number 14 with a gold coating on it. Some versions of number 14 are not safe as well, so you are better off avoiding welders glass for solar viewing.

A long time ago people used to think you could used dark exposed negatives as a kind of solar viewer. Those are not safe and that should NOT be used.

There are some safe solar glasses that are sold by planetariums and on the Internet that can be used. They are marked as solar glasses. They are used as glasses for your eyes, not for any kind of powered viewing.

There are filters and filter kits, sold by companies like Opt over the Internet that can be added to a telescope to make it safe.

I have a Daystar white light filter that is a safe filter marked for solar use. I also have Baader planetarium filters that are safe for solar viewing.

Some filters kits are designed for photography only and may not be safe for eyepiece viewing. To keep things simple at HJRO and with my own solar kits I only have solar filters and telescopes that are suitable for visual viewing with humans looking into the eyepiece. If I avoid the photographic only filters I can avoid accidentally using one for visual human use. So to be safe I only use visual solar filters rated for safe viewing.

Filters themselves can be damaged as well and have to be inspected each time before they are used. The best way to inspect one is by using a regular light bulb and look at that incandescent light bulb through the filter. If there are no cracks or holes that can be seen it can be safely used.

For filters that attach to telescopes you need to make sure they are firmly attached and will not easily be removed and can't just fall off or be blown off by the wind. Such accidents could be fatal and cause instant blindness.

Finders and other optical aids have to be covered when looking at the sun. One member told us he had his hair catch on fire from light from the finder when looking at the sun through his telescope. He didn't realize that the finder could cook or blind him if it was uncovered. At HJRO we keep the finder and the c14 covered during solar viewing.

Also the solar observer cannot tolerate any playing around near the telescope, or goofing around. A goal for safe solar public events is to keep others away from the front of the telescope when people are viewing. Make sure nobody is touching or playing with the front end of the telescope and that the filters are very much secured in place.

Constructed filters need to be constructed and taken care of. I have safe solar filters that I made and some I bought. The ones we make have to be inspected and constructed to resist any kind of malfunction and stored properly to avoid moisture damage and scratches.

That's about it for the security info on safely viewing the sun.

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