Venus again

Hi all,

Venus again, intersting to see the difference in size and phase over 13 days.. I needed, the best 750 out of 30,000 frames to capture on the 21st. Thankfully, I got something. I used a Continium filter on a cge 11 inch SCT. I hope to get a few more shots over the next few weeks (clouds allowing: blink: ), to compare the size and phase of the planet.






Taken from Waterford, Ireland

Best regards

Steve

Hi Steve,

Those images are very nice indeed sharp as a pin processing is excellent. Venus is one hard planet to image because of the amount of shimmering it does on the screen. The size difference is incredable in just two weeks.

Well-done mate.

Carl.

Very nice - a couple of questions - how many stacked frames is the typical ball park? 750 sounds quite large. Does S/N improve anything like significantly beyond a few tens of frames?

I've imaged venus a few weeks ago (okay with a Dob at that point) and only stacked about 20. (Your images are superior to mine BTW).

Second question - what's a Continium filter?

Mark

Hi Steve,
A fine pair of images there, you should try running something like starrynight, this planet is going to get real big soon enough.
Do you use the filter to reduce the glare of the planet while imaging ?

Very nice set of comparitive images Stephen!
Michael.

Thanks folks

Carl, Venus is indeed one hard planet to image, it was jumping around the screen like an "out of focus" ping pong ball. Thanks for your comments, I hope to create a montage of the size and phase differences over the next few weeks.

Hi Mark, thanks again. In my own case, the amount of frames I select is based on the quality of the AVI's captured, and then some "Trial and Error". Generally it would be between 700 and 1000, however, this is down to experimentation, rather than using a scientific calculation (Nyquist theory). I generally would create a reference frame from the best 50 frames in registax, and then take it from there, depending on the quality of what was captured. In the Venus case, I found I had to capture alot of frames, due to athmosphere conditions and the low position of Venus itself, and try to weed out the best 750, which seemed to generate the best results, in this case. More experienced, planetary imagers on the site here, would be more qualified to advise you on the optimum methodologies. In my own case, there is still a big element of trial and error (but I enjoy the learning experience:silly: ).

A Continuum filter is actually a solar filter (to be used with an appropriate Full aperature Solar filter for Solar observing) that I use for sunspot observation/imaging (not much happening there though). I thought by using this on Venus it may help "Steady" the image a bit better, due to its narrow bandpass. I have just been experimenting with it, as I dont have a dedicated Venus filter at this point in time. Hopefully, I will purchase a dedicated Venus filter in the future, which may generate better results!

Hope this is of use.

Best regards

Steve