5 November 2006

First Light

This morning I bought a used Nikon CoolPix 990 digital camera to replace the CoolPix 950 that I dropped, breaking the lens mechanism. When I got home I took it out to try it out on the Sun. I don't think the light buckets on the CCD are small enough to capture sunspots without using a binocular or telescope to magnify the image for the camera.

This is an image of the Sun with the camera set at maximum wide angle.

Here is the Sun at maximum optical zoom.

Here is the Sun at maximum digital zoom.

This image was made with the camera set at maximum zoom with the Nikon TC-E2 2x Tele Converter added.

Here I am using the TV-E2 and have zoomed the camera to maximum digital zoom (4x).

I need to repeat these tests another day when the sky is clear.

We were always advised to eschew the digital zoom because it made lousy pictures so I figured I should find out just how lousy they are since I used it in the test above. I was surprised at how little the image suffered from it. Here is the maximum optical zoom on the camera and a full size section of that image.

This is with the camera set to 4x digital zoom and a full size detail.

There is some obvious image degradation with the digital zoom but at the size I display the images in this blog it isn't apparent.

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Observing Location	PSC
Observational Period	1300-1345 EST
Atmospheric Conditions	Cloud Cover Overcast Temperature Cool Wind Calm Humidity Moderate Feels Like A little raw Transparency Poor Seeing V
Instruments	Canon 15x50 IS binocular w/Baader AstroSolar filter film - Charlie Nikon CoolPix 990 w/TC-E2 2x Tele Converter and gold welder's glass
Observing Party	Charlie Ridgway

Target Sunspots Constellation Lib Category Solar Time 20061105.1300 EST Comments Heliographic Latitude (B0) +3.91° Heliographic Longitude (L0) 119.98° Position Angle (P) +23.65° Carrington rotation number (CR) 2049 When I left downtown there was a nice blue sky but it had clouded over again by the time I got home. Since I had been seeing some strong shadows I went up to the oval anyway hoping that there would be some breaks in the clouds that would permit me to count the sunspots. That didn't happen although I sat there for 45 minutes experimenting with my camera. After I got back home and was reviewing my pictures I noticed nice blue sky again, at least to the NE. The only thing I could tell about the Sun was that there were two bipolar groups there.   Groups Spots R North 0 0 0 South 2 ? 20+ Total 2 ? 20+ R = (Groups * 10) + Spots) Group 921 Heliographic Latitude -9° Heliographic Longitude 160° Mcintosh System I don't see the numbers of small spots in this group that I was seeing there last week, but don't know if they are really gone or if they are being obscured by the constantly moving clouds. Group 922 Heliographic Latitude -14° Heliographic Longitude 143° Mcintosh System The spots in this group apear do be larger and darker again today.

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Observing Location	TotL
Observational Period	1945-2145 EST
Atmospheric Conditions	Cloud Cover Clear becoming Overcast Temperature Cool Wind Calm to Gentle Breezed gisting to Fresh Breeze Humidity Moderate Feels Like Cold I hadn't planned to observe tonight but when I came home from dinner it was clear and I could see stars so I grabbed my gear and headed downtown hoping someone else would show up. About 2030 EST it started getting cloudy and shortly became overcast. The moon was still visible through the clouds but as they thickened it lost its crispness. Transparency Goon becoming Opaque Seeing II
Instruments	Canon 15x50 IS binocular - Charlie Nikon CoolPix 990 w/TC-E2 2x Tele Converter - Charlie
Observing Party	Charlie Ridgway

When the moon is full it is as if the eternal light of the Great Spirit were upon the whole world. Black Elk Sioux

Target Moon Constellation Ari Category Lunar Time 20061105.2030 EST Comments Lunation 1037 Phase Waning Gibbous Age> 14d20h15m Fujk +12h31m Elongation 171.66°W % Illuminated 99.5% Magnitude -12.7 Altitude 40.85° The Moon was full today at 0759 EST. Crater Neper, right of Mare Crissium, looks like the wall rises up from the terminator-looks like a burst pimple. East wall is completely lit and floor in shadow Aristarchus doesn't look any brighter than Proclus, whick has a bright streak going nearly to Mare Serenitstis. Lunar halo is bright at the limb then gets dark then bright again before turning red. When it was shining through the clouds the halo was 5° wide. Mare Smythii is right on the terminator. All the mountains around Mare Imbrium; Alpa, Caucusus, Apennines and Carpathians, are hard To see Leading edge of approaching clouds illuminated by Moon looks like parchment.

Here is the consolation prize on nights like tonight when the clouds come in.

full size image You can even see the gegenschein of Times Square.

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I played with the camera a bit tonight trying to figure out exposure for the Moon and how to use the camera in the fully manual mode.

If I were photographing the moon with a manual camera I would use the Sunny 16 rule (1/ASA @ f/16) since the Moon is in full sunlight any time we can see it. To even try this I first had to figure out how to set both the shutter speed and the aperture. By accident I discovered that if I went into Aperture mode and set an f-stop there and then went back to Manual mode the f-stop I had selected in Aperture mode was what Manual mode would use. I did the same thing in Speed mode and Manual mode remembered the shutter speed I had selected in Speed mode. So now I could control both settings. I made a series of exposures halving the amount of light recorded on each subsequent exposure until the preview image looked too dark then went a little farther (I know from experience not to trust the little LCD screen). Here are the unadjusted results (I have cropped the images to show just the moon and resized them to fit on the blog, but didn't adjust exposure at all).

I made the images with the w/TC-E2 2x Tele Converter and 4X digital zoom. The camera was hand held against the shoulder of my tripod to provide some stability. When I get serious about doing this I am going to have to bring my Bogen Magic Arm.

I also tried taking some pictures through the binocular. I had a lot of trouble finding and staying on the optical axis of the binocular. I will need a mount of some kind to make that easier. Focusing was also a problem but I need to get a mount before I can do anything about it as it is taking both of my hands to keep the camera in place once I find where that place is.