Posts Made By: Jeff Blazey

A genuine Starfire lens at a VERY attractive price:

http://www.vampfangs.com/Starfire-Lenses-p/fxstarfire.htm

Roland, are they FPL-53?

Jeff

Ok, who else besides me saw the 5 moons of Jupiter tonight all lined up in a nice, very straight line. It was 10:20 PM Eastern time in Lebanon, Ohio.

Jeff

Barry makes good lenses. 11" F12, old Cave Observatory mount modified with a 10" Mathis drive system and Cave pier. Built the tube assembly my self....all 110 pounds of it.

This scope is magnificant, giving me the best views of Jupiter, M13, M27, M92...I've EVER had. Plays nice with my Chromacor too.

Jeff

I've really been enjoying Jupiter this season. With the Moon's orbital plane edge on to the earth all kinds of neat stuff happens. For example, did anyone here in the eastern time zone in the US happen to see a moon reemerge from Jupiter's shadow at around, according to my cell phone, 10:51 PM (I'm in southwest Ohio)? I at first noticed it about 15 arc seconds off of Jupiter's limb and thought it was a dim star that Jupiter had occulted. However at high power I quickly saw the gibbous nature of the disk and watched it over the next few minutes grow from a smile to a bright disk. Major cool 8) and caught the event quite by accident.

Jeff

Well I left the scope out last night shrouded so as not to be dripping with dew in the morning. Set the alarm to 6:00 AM. Got up with the usual rice krispy joints, chugged a cup of speed and went outside with the eyepiece case. With the birds bitching at me to keep it quiet since they're trying to sleep, I removed the dew soaked sheet, turned on the power, swung the scope around to Luna, popped a couple of Denk 14's into the binos and focused.

BAMMMM!!!!

Calm, dead calm and SHARP. Slid the power switch over to 2X..BAMMM!!

Good lord, the detail was spectacular and the atmosphere was allowing the 6" to go right to the limit. I could have spent the rest of the morning looking at just Plato. The cratlets were obvious despite the low sun angle but that made the ripples on the floor stand out. The jagged, long black shadows casting down from the rim peaks made for a decided 3D effect. The bite mark in the wall was especially compelling as I could look right down into it.

I popped the 10MM plossls in, giving me 300X. Oh my goodness. Moved over to Copernicus. What a treat as was the straight wall. I then used the controls to just scan along the terminator, looking for a landing spot.

Then I thought "wait a minute" and nudged the scope over to Mars. "This is just too cool.", I muttered as the small gibbous orb was giving up a sharp jagged polar cap and clear, crisp surface detailing.

At that point dawn glow was intruding and the lens was dewing up a bit but I noticed Venus had found her way out of the woods so she was my last stop before breakfast. Though small and low in the sky she was sharp, and a dazzling beauty.

This was an unforgettable morning and drove home to me why I like the visual side of it so much, especially for solar system stuff. Yeah I've seen some truly spectacular images but they in no way give me that visceral, emotional jolt and awe of this live visual feed injected directly into my head. It's the best reality show...EVER.

Jeff

So, how come no one's done Saturn yet?

Well I've finished off the tube assembly for the ISTAR 6" F10 doublet. Came out rather nice if I say so myself.

Next up is the optical testing. As part of that procedure, I'll be doing a side-by-side comparison with my old 6" F10 Jaegers. A very preliminary check out with the bare tube a month ago was quite encouraging.

A doublet should be a good test product for a new vendor. They're "easy" to make and if this sample is good, well that's also good news for us ATMers.

I'll submit the report when the weather is suppose to clear...sometime in July I've heard.

Jeff

The title pretty much says it all for this helpful hint.

Recently during two achromat ATM projects, after squaring up the focuser with a laser, I collimated the scopes using a well made Cheshire by "lining up the dots". According to this procedure, both scopes were "spot on" (pun INTENDED) in their collimation and this has been my experience in previous achromat projects.

However, out under a star test, both scopes displayed classic astigmatism at high power. One was quite mild and easily swallowed by the airy disk. The other was moderate and just barely fit into the airy disk at focus but would spill out during rougher seeing.

I did the usual drill of swapping out diagonals and eyepieces but the results were always the same. I was getting fustrated, then I recalled something Roger Ceragioli said in an e-mail exchange we had concerning an oiled triplet that I got from him. He basically said, do the Cheshire thing but don't trust it, always follow up with a high power star test. If you see astigmatism, adjust the lens collimation to see if it goes away.

So that's exactly what I did last night with both scopes.

BINGO!! It only took a simple tweak of one "push" screw on each scope and both were free of astigmatism and gave excellent star tests.

Rechecking with the Cheshire today showed the spots to be slightly offset from one another.

Lesson learned! Maybe one of the practicing opticians on this forum can give us an explanation of how the Cheshire is suppose to work and why it may give misleading results.

Jeff

These guys have taken up shop in an large Sycamore so I hauled out my 1986 vintage AP 130 F8 and started looking at them with my Denk IIs from about 100 yards out. Couldn't resist trying to take a few shots with my old school Olympus digital. I've never taken bird pictures before but I was having so much fun. Hope you like them.

Jeff

...just how SHARP a good achromat can be when using a good green filter.

Last night I was tweaking my Istar 6" F10 achromat via star testing thru my green Baader solar filter. I had dialed in the scope to the point where I was getting really good, round intra/extra focal diffraction patterns, and a tight round airy disk with a very dim & uniform first ring. Very nice. Then I decided to turn my attention to the Moon.

Oh my goodness. I was INCREDIBLY sharp. But green of course and I have to say I really did not mind the green at all, not even a second thought, as the image was soooo sharp. The view of Saturn was a knock out as well.

No CA at all!! ;-)

I did something similar decades ago with an old Jaegers 6" F10 and was amazed then too but I had forgotten over the years just how sharp a really good achromat can be in green light.

Jeff