Posts Made By: Joe Baldwin

C9.25 , 2.5X Powermate, 800 frames in Registax. seeing 7/10 COLD!

As promised, here are my results comparing image quality with and without an IR blocking filter on Jupiter. In the last thread on this subject, I compared results on Saturn and felt that a very small improvement was noted with the blocking filter present. I need to clarify that the acquisition software was set to automatically adjust the white balance continously so the gross effects of the filter were largely cancelled out. Here, I've set the white balance in the IR filtered case and then unselected auto white balance so that the unfiltered acquisition was taken with the same settings. All other processing was identical on the filtered and unfiltered images. Registax was set to discard 10% of the worst images ( by quality)

The top image is IR filtered. The middle image is with the IR filter removed and all settings the same. The lower image simply attemps to rebalance the color to match the filtered image. It appears in this case the unfiltered image is marginally better. What I cannot rule out is that the difference is do to seeing or focus since I had to remove the filter, refocus and acquire. Further study is required but I feel that the improvement with the IR cut filter would be very small if any and probably only apparent when seeing conditions are very good.



C9.25/1.25" adapter/Powermate 2.5X/(filter)/Toucam Pro 2

seeing 6/10
1080 frames Registax2

I would pay dearly to finish a 4 hour road race 2000 feet ahead of the guy who didn't have aero rims

You may want to think about backing off the magnification and trying to get a wider angle view. You could create an animation of Jupiter and its moons or put Saturn against a backdrop of(brighter)stars. If you go for high mag, you can get better results by setting the shutter speed as high as possible and increasing the gain to compensate. You'll get more noise but you can "freeze" moments of good seeing.

I've waited all season for seeing this good.

Need a solar filter for a C8. I'm planning on using the Baader AstroSolar film and making my own. Am I better off getting the smaller sheet and making an off-axis mask or popping for the larger sheet and doing a full aperture filter? There seems to be some buzz that a smaller aperture is less succeptable to poor seeing but I've yet to see anything quantitative. I'll be doing both visual and imaging.

Steve,
I spent some time this past weekend hunting down planetaries and spent a few minutes looking at this one as well. In my 9.25" under very dark skies, it was a steady glow in the eyepiece. The central star did seem to blink in and out as the seeing allowed- maybe thats supposed to be the blinking part.

Finally got to use my new Bino setup. Denk I's with a C9.25, UO Konig 16mm eyepieces. Started with the moon, Took me about 30 seconds to set the correct interpupillary distance and merge the 2 images. I actually felt like I was looking out a porthole, hovering above the moon. Cool

In response to Rolando's earlier thread, I dug up some Jupiter images from last year. At the end of that imaging run, I stuck an 850nm IR bandpass filter in front of the webcam and cranked up the gain ( A lot). The S/N was quite low but I was amazed at how much got through. Even more curious, the IR leaked into all the channels ( R,G and B) about the same. In my notes I noted the webcam gain was pushed up to the max and the shutter speed was slow but I didn't write down the exact value. I would estimate based on the gain increase,the image intensity and assumed slowest shutter speed that about 2% of the energy that is present in the unfiltered case is collected in the 800nm-900nm range ( assuming my bandpass filter is perfect).

setup: C9.25, 2.5x powermate, Toucam 840, Edmund Sci IR bandpass filter

My first view through a binoviewer was the moon. I felt a little dizzy because the illusion of depth was so real I swore I was "hovering" above the moon