SharpCap Forums

As my stepmother would say: "It was one of my lesser successes" which revealed her optimism.

An excellent showing for 5 degrees above the horizon!

Brian

Thank you, Dave. Excellent images! The Dumbbell Nebula is a planetary nebula, so we have access to its spectrum, courtesy of Professor Karen B. Kwitter, Williams College: https://web.williams.edu/Astronomy/research/PN/nebulae/index.php I've zoomed in on the area around the hydrogen-alpha (Ha) line: ...

Robin, The only problem with the photometric method is that the ratios change with the bandwidth of the filters. For example, a 3nm Ha filter will isolate the Ha emission line, but a 7nm Ha filter will also capture two nearby NII lines. The NII lines are just as strong as Ha in some nebulae. The bes...

Hi Robin, Yes, the total integration time of SII will be seven times longer than Ha but only if we choose a long exposure for SII so that the per-sub SNR is the same as Ha. In reality this is impractical, so we need a longer integration time for it. Regarding light pollution, I am assuming that it i...

It is that time of year again for the Tadpole Nebula in Auriga. Last year was my first attempt at it. Sara Wager inspired me with her exceptional image using Ha and OIII. https://www.swagastro.com/ic410.html Like most people, I chose a single exposure and then captured an equal number of frames. It ...

Tim, I've held off from replying due to the word "DSO" in the title, but now that I see that the topic has shifted towards imaging stars, I can add something to the discussion. Feel free to use sub one-second exposures for the Lyra double-double. They are bright at 6th magnitude. If you ha...

Anthony, I know that some people swear by Bahtinov Masks, but I stopped using mine for two reasons: you need a bright star, and you risk accidental loss of PA putting it on and taking it off if you bump the tripod/mount. Also, I focus often, after slewing to a new object and after a filter change. I...

Gary, I recognize the document in the screenshot of your original post: AAVSO's CCD Photometry Guide. I agree with Robin. You need a very stable light source. I tried an Electroluminescent Panel but found that the brightness varied. I ended up using an LCD monitor. I've attached results for a run at...

PYTHAGORAS

Geological period: Eratosthenian (From -3.2 billions years to -1.1 billions years)
Dimension: 129.0x129.0Km / 78.0x78.0Mi
Height: 4800.0' / 14500.0ft

Virtual Moon Atlas says that it is in the northwest quadrant, not southwest.

What do I win?
BTW, decent photo

Brian

Hi Bruce, Awesome image! For inspiration (and humiliation) I visit Sara Wager's website. Here is her rendition of the Bubble: https://www.swagastro.com/ngc7635.html Astro-Physics' website also shows a cyan bubble: https://www.astro-physics.com/ She did not specify, but I believe it is SHO. Plenty of...