I am attempting to set the sharpcap controls to photograph the eclipse. When I aim the telescope (with a solarite filter) at the sun I get a black screen in sharpcap.
I have successfully loaded the sharpcap software, put the sv305c camera in the eyepiece adapter of my 6 inch Meade reflector, connected the camera to the laptop, selected the sv305c camera and aimed at some trees. I got a clear (slightly granular) picture of trees.
Next, I looked at the sun thru a 26 mm eyepiece, with a solarite filter on the telescope input. I saw a low light level yellow sun.
However, when I attempted to view the sun using the sv305c camera and the sharpcap software, I got a black screen, no picture. The histogram did show some pixels receiving light.
I have tried several changes to the numerous settings with no improvement. What sharpcap control settings should I use to see the sun thru the solarite filter and sv305c camera?
sharpcap eclipse settings
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Re: sharpcap eclipse settings
Hi,
I suspect you have a combination of up to 3 problems
1) Camera settings have too short an exposure/too low gain, so the image is dark
2) Focus position may be quite different for camera compared to eyepiece, so may be badly out of focus
3) The area you see through the camera will be much smaller than with the eyepiece, so you may be looking at a part of the sky just away from the sun when using the camera
The technique I use in this situation is as follows
* Turn up gain and exposure until the image is relatively bright - maybe 50% on the histogram on average. Ideally turn up gain first to keep the frame rate running fairly quickly
* If you struggle to get anything usefully bright without going over 1s exposure, use the display stretch to brighten the image
* Once you have some decent brightness in the image, start moving the mount a little in each direction. You are looking for the direction where the image gets *brighter* as if you are not yet pointing at the sun, the brighter direction will move you towards the sun
* Move the mount gradually in the direction which makes the image brighter. If the image becomes too bright so that it is all white turn down the exposure/gain/image stretch to get back to a reasonable level and continue moving towards the brightest area you can find.
* Once you have found the brightest part, the camera will be looking at the sun - now on target
* Make sure gain/exposure/stretch adjsuted so that the image brightness on screen is about 50% level and start adjusting focus
* You may need to tweak gain/exposure again as you adjust focus
* At some point you should get the image come into focus - if you can find the edge of the sun that can help as it is easier to spot the edge come into focus than to see focus detail on the surface.
If you struggle to get focus at any focuser position then you may need to add/remove extension tubes to get the camera further back or closer in to the telescope.
cheers,
Robin
I suspect you have a combination of up to 3 problems
1) Camera settings have too short an exposure/too low gain, so the image is dark
2) Focus position may be quite different for camera compared to eyepiece, so may be badly out of focus
3) The area you see through the camera will be much smaller than with the eyepiece, so you may be looking at a part of the sky just away from the sun when using the camera
The technique I use in this situation is as follows
* Turn up gain and exposure until the image is relatively bright - maybe 50% on the histogram on average. Ideally turn up gain first to keep the frame rate running fairly quickly
* If you struggle to get anything usefully bright without going over 1s exposure, use the display stretch to brighten the image
* Once you have some decent brightness in the image, start moving the mount a little in each direction. You are looking for the direction where the image gets *brighter* as if you are not yet pointing at the sun, the brighter direction will move you towards the sun
* Move the mount gradually in the direction which makes the image brighter. If the image becomes too bright so that it is all white turn down the exposure/gain/image stretch to get back to a reasonable level and continue moving towards the brightest area you can find.
* Once you have found the brightest part, the camera will be looking at the sun - now on target
* Make sure gain/exposure/stretch adjsuted so that the image brightness on screen is about 50% level and start adjusting focus
* You may need to tweak gain/exposure again as you adjust focus
* At some point you should get the image come into focus - if you can find the edge of the sun that can help as it is easier to spot the edge come into focus than to see focus detail on the surface.
If you struggle to get focus at any focuser position then you may need to add/remove extension tubes to get the camera further back or closer in to the telescope.
cheers,
Robin