Posts Made By: Alan Friedman

Hi Eric -

Excellent! I'm glad the seeing finally cooperated for you -

Alan

Stitching together these two images makes a nice bridge across the Mare Frigoris and a short journey from Plato and the Alpes to Timaeus embeded in the giant crater W. Bond. The high walled crater is Anaxagoras on the left wall of older Goldschmidt - the foreshortened crater near the limb with small crater in center is Scoresby.

Assembled from two exposures taken with my 10" mak at f14.6 (and much help from Rukl's Atlas of the Moon).

Alan

Hi Damian -

That certainly whets the appetite for staying up late.

... fabulous!

Alan

Truly fantastic!!

And even more amazing that this is through blue filtration.
Don't know how I missed this the first time around - I'm glad that it came back to the top of the thread list.

Alan

Hi all -

An image from Tuesday night - the solar system's most massive moon preparing to transit its most massive planet.

details:

10" A/P mak/cassegrain and 2x Televue Powermate.
LRGB composite - luminance compiled from 550 frames through red and green filters.
DMK 21BF04 firewire webcam and manual RGB filterwheel.
Capture at 60ms shutter/ 15 fps
Captured with AstroIIDC/ processed in Keith's Image Stacker and Adobe Photoshop in Mac OS.
seeing 5-6/10, good transparency

steady skies!
Alan

Hi all -

Thanks for sharing your comments on my previous Jupiter/Ganymede image from May 31. I took quite a few RGB sets that evening - but the seeing declined rapidly at ingress (surprise, surprise!). Even though the transit images were a little disappointing I thought I would share a comparison view showing the moon against the disk. Ganymede transits about once a week - we are treated to 5 of them this month - but it still feels like a special event to catch one.

best -
Alan

Hi Robert -

Thanks for posting these very fine images!
Looking forward to seeing more of your work.

Alan

Well, I'd say this one deserves a comfortable chair, a cup of coffee, and a longer look.

Unbelievable!

Alan

Damian -

Another view of astounding clarity. I've come back to it a numbr of times this morning - the rendering of Europa is quite special.

Alan

Greetings friends,

I have spoken with some of you on my project to retrofit my APQ 130 with an alternative to the Zeiss M80 helical focuser. Just yesterday I received a Starlight focuser (with 2.5" travel) made by Werner Schmidt of Starlight Instruments and outfitted with a custom adapter to mount the focuser on the unmodified rear threads of the APQ tube. I had a chance to attach the unit last night and take some pictures which I have attached below.

A detailed report will have to follow - clouds kept me from trying the focuser at infinity. Those of you who have used a Feathertouch with its dual speed pinion know that it is a very smooth functioning unit. My first tests confirm this - it moves effortlessly with no image shift whatsoever. A braking mechanism allows fine control over the resistance in both fine and coarse adjustment.

My goal in this project was to permit enough infocus to allow my Coronado solar set-up to come to focus using the Zeiss/Baader MarkV binoviewer (something I could never achieve with the original Zeiss helical.) The minimum extension of the Feathertouch (with the rotating finder ring removed) will gain about .3 inches over the minimum possible with the Zeiss helical - which should give me just enough. This unit can extend slightly longer than the Zeiss helical, but without the drawtube option it will be necessary to use an extension in some applications. I have shown the focuser with an Astro-Physics 2" compression ring extension which allowed all tested eyepieces to come to focus using the Zeiss T2 prism (I tested on a terrestrial subject 150 meters away - infinity will require less extension). Using a 2" prism, mirror diagonal or binoviewer might eliminate the need for an extension with some eyepieces.

The focuser felt fully comfortable with the weight of the binoviewer and eyepieces and added leverage of the 2" extension. That said, this solution does not have the same heft of an Astro-Physics 2.7" rack and pinion focuser. An imaging application that uses a heavy CCD camera and additional lens elements behind the focuser might require a heavier duty solution. For visual applications carryng 5 lbs or less this should be fine.

I will post additional comments once I have tested the unit more extensively under the night sky. If anyone is interested, Werner has made additional adapters which he will be selling directly. I am not sure how they will price out in production, but the adpater should run approximately $100 and the focuser with brake and compression ring fittings runs $335.

best wishes,
Alan Friedman