Posts Made By: Alex McConahay

There are $100, 30mm, 82d AFOV eyepieces all made in the same factory (or maybe not, who knows?) and sold under lots of names. Mine is BW Optic, I think. They make good finders, and if you are not too picky about the edges, even pleasant viewing eyepeices.

Alex

Having a fine focuser helps, but not $400 worth if that is the only time you plan to use it.

I do have some questions, though, about your focusing procedure. If the temperature changes, the tube will change in length, and thus in focusing position. Therefore, it does not do much good to focus the night before. And, besides, what makes you think the focus you get the night before would be any better than the focus you get the day of the eclipse? You will be using a filter for the solar eclipse, and not for the previous night's focusing. And focusing on the edge of the solar disk prior to first contact is probably even easier than focusing on a star. Besides, you will have to refocus several times during partial phases before you get to totality.

If this is your first solar eclipse, do not worry about the photos.......Watch the eclipse. This will be a long one, so you have time to do both. But the important thing is to watch the eclipse.

You might get some benefit from looking at this http://www.alexastro.com/Alex%20Home%20Page/Articles/Ranger_20D%20Eclipse.pdf
It is my notes for the Egyptian Eclipse.


Alex

What problem is the buyer having?

Alex

Buy Velcro!!!!!

Alex

Just what are you planning to put up on that tripod that weighs 132 pounds. The GM-8 plus its maximum weight carrying capacity has to be less than, what--50 or 60 pounds?

Alex

Does it not work because you cannot attach the 85 to the plate, or because you cannot attach the plate to the mount?

Alex.

What ad #, Charles?

What are your settings for what dates (how far back) your ads will show?

Alex

Your only ad appears to be from May--it might not show if you have only "show last week." in your display settings.

Alex

I caught that visually at the Texas Star party last April. It is more like a black void than a visual object. You did a nice capture on it.

Alex

Time is not of the essence here, Robert. YOu will have five or six minutes during what is the longest eclipse of the century. Your longest exposure at ISO 200 will be in the one to two ( four?) second range---you have time to take 150 of those. (and you probably want less than half a dozen.) If you bump your ISO up to 1600, you can shave those two second exposures down to one quarter second. You don't save all that much time. On half a dozen shots, you save what? ten seconds?

On the other hand, you may want Bailey's Beads at 1/1000 of a second, If you have bumped your ISO to 1600, you have to move the shutter to 1/8000 for an equivalent exposure. I doubt your camera will get that fast.

Now, we could discuss the relative noise levels of 200 v. 1600. It does matter, 200 is smoother, but probably not as much as it used to with older DSLR's.

I think you should practice just how many shots you can get in five minutes or so at 200 ISO versus what you can get at 1600 ISO. I think you will find that popping your ISO is not really that useful.

Note--other people may have slightly different exposure times for their various eclipse shots. Point is, you want a wide variety of exposures since when you composite, the far out corona shot is going to be a lot longer than the edge of the sun shot. You need them all.

Your boat pictures mean you have a moving imaging platform. Is that the source of your "out of focus?"

Alex