Sunspot photos taken with my home built solar camera

Close-up of sunspots   Another close-up of sunspots   Yet another close-up of sunspots

Another close-up of sunspots   Yet another close-up of sunspots   One morer close-up of sunspots

Here are a few of my first decent sunspot photos. I took these photos of the huge sunspot groups seen during the spring of 2001. The full sun photos these enlargements were taken from are at the bottom of this page.

The solar camera on a photographic tripod

Close-up of the solar filter and sun shade

Close-up of the camera body and barlow lens

Close-up of the saddle on the tripod

Here is a photo of the home built solar telescope I used to take the above photos. It started life as a cheap 70mm refractor. I removed the focuser assembly and added an extension tube made of PVC pipe. A 2in barlow lens doubles the focal length of the scope from 700mm to 1400mm. A Pentax K1000 35mm camera with a cable release is used to record the images.

The second photo shows the home built solar filter I made from a piece of flat, first surface mirror I bought surplus for a buck. The Aluminum coating on the mirror doesn't quite block all the Sun's light and lets just enough through to make nice photos. I put the piece of mirror in a wooden holder made to slip onto the front of the scope. A cardboard square on the front shades the camera and keeps me from having to squint into the sun while aiming and focusing the camera.

The third photo shows a close up of the camera end. The black cylinder in front of the camera body is a 2 inch 2X barlow lens used to double the focal length of the telescope. The barlow lens attaches to the camera body with a T-ring adaptor. The barlow lens then is friction fit into the piece of PVC pipe serving as an extension tube. Focusing is accomplished by sliding the PVC extension tube in and out of the telescope tube and then clamping it tight when focus is found.

The fourth photo shows how the whole assembly is mounted on my photographic tripod in a quick and dirty saddle I made from a piece of scrap wood, some Aluminum angle and some hose clamps. It's kind of ugly, but it works. Maybe someday I'll make a neater saddle. The other two hose clamps and the silver knob above them are the clamping mechanism that allows me to lock down the PVC extension tube once focus is found.

My first attempts at photographing the sun were spoiled by poor contrast. I quickly determined that the un blackened inside of the refractor tube and the PVC extension tube was causing horrible internal reflections. And worse yet, the PVC pipe was translucent and allowed much light to pass right through. Painting the insides of the long narrow tubes presented a problem, so I decided to roll up black poster paper into a cylinder and insert it into the scope. This worked wonders and I am now getting reasonably good photos.

UPDATE! I have modified the camera by adding a second 2X adaptor. While rummaging around in my camera bag I found my old Pentax 2X adaptor. I slipped it in between the T-ring adaptor and the camera. This setup not only doubles the magnification, but also seems to increase the contrast and produce better photos.

Full sun photo with sunspots #1   Full sun photo with sunspots #2   Full sun photo with sunspots #3

These are the full Sun photos the camera takes without the second 2X adaptor in place. The Sun just fills a 35mm frame. The enlargements above were taken from these photos. The camera still has less than ideal contrast even after the modifications I made to improve it. As a result, much processing is needed to bring out details in the sunspots. This makes the Sun's disk look "funny" in the photos. Click on them to see the full size photos.



These are the sorts of photos the camera takes with the second 2X adaptor in place. click on the photos for the full size image (they are large and will take a while to download). Now the Sun is much larger than the film frame and it is possible to get much more detailed images of the spots. The dark bands and blotches on the sun seem to come from shooting through thin clouds and haze. The contrast enhancement needed to bring out details in the sunspots also exaggerates the slight brightness differences from shooting through haze and thin cloud. It has been amazingly difficult to get a 100% clear day since I started trying to shoot the sun. There always seems to be some thin scum that is only visible when backlit near the sun


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