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Sculptor Galaxy (NGC 253)

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Posts Made By: Alex McConahay

July 29, 2003 04:05 AM Forum: Film Astrophotography - Imaging and Processing

Some Newbie Questions/Concerns

Posted By Alex McConahay
Chris,

As for polar aligning--it must be done well. A couple of other respondents have given good advice.

As for focusing. You should see sharp stars in the viewfinder. However, even sharp in the viewfinder may or may not be at perfect focus. Make a Hartman mask (a front cover with two holes about two inches around). When something is out of focus, you will see double. When in focus--you will see single image.

The extender will help move the camera, but not change (practically speaking)_ the focal length. The focal length is set by the optics. Most SCT's have enough focus travel to handle the camera without getting fancy.
The question is simply one of whether you have enough travel in the focuser. As you focus, do you run out of travel? Do you get to what may be a focus, and then go past it?

An F 3.3 focal reducer will seriously vignette. (A 6.3 does some pretty strong vignetting.) And you do not want to use it with an OM-1.

Alex


July 30, 2003 12:29 AM Forum: Film Astrophotography - Imaging and Processing

Refractor and Astrophotography Help

Posted By Alex McConahay
With all due respect, you will not be able to get good astrophotos without doing a whole lot more work than you look like you are willing to do. And using much better equipment than you are contemplating.

There are many things that can go wrong in astrophotography. You need the best mount, good optics, and then think about camera stuff......

And the night of the exposures, you are going to have to worry about polar alignment and a whole lot more.

Don't mean to discourage you, but I do want to open your eyes.

Alex

August 14, 2003 03:01 PM Forum: Equipment Talk

Anyone else have a problem w/the pic in this add?

Posted By Alex McConahay
At first I thought it was faked. You know, the way NASA put together those moon shots to "prove" that man had been to the moon.

Then I saw this special on Fox News (We report--You decide.)

Apparently this picture was taken from Los Angeles, California. In this part of the world, the sun bounces off the Pacific Ocean. The bright reflection has been known to light up even the fully eclipsed moon.

Remember Los Angeles is really part of Hollywood.

For the details, see badastronomy.com

(Badastronomy.com has nothing to do with this picture--but it is always quaint and curious to see what those know-it-all-and-you-don't omniscient "Skeptics" think of the news and world events.)

Alex

August 16, 2003 06:14 PM Forum: Equipment Talk

Naming those who do a poor job.

Posted By Alex McConahay
Eric,

I know what you mean, but I would rather have it the way it was said. The point of the posting seemed to be that "there's good customer service, and then there is bad. Here is a story that illustrates what I like." I much prefer that class and style to one that says "XYZ is bad and ABC is good. Avoid XYZ at all costs...." The style of the original poster is positive, the other way is somewhat negative.

And the fact that Scott Losmandy is singled out is not bad. After all, isn't that how we all want our lives run. We recognize the good, and give them kudos. ANd we mention what was not good, but don't necessarily name them outright. (Think of the last staff meeting, or sales meeting you were at.)

And besides, from what I have read, any organization has its good and bad. (I've seen complaints about Losmandy--and good comments about everybody else I can think of.)

It takes twenty "attaboys" to make up for one "Awe Shoot." (or something like that).

In short, I'm hardly a sunshiney Pollyanna, but I prefer positive.

Alex
Alex

August 17, 2003 02:59 PM Forum: Equipment Talk

CGE 1400 Purchase

Posted By Alex McConahay
Don,

Nobody has answered your second question about --should you sell the C-8.

I say no--for several reasons

The first is, assuming it is your only other scope, you will need it for those nights you want to do some kind of outreach (You do, I assume, occasionally share the heavens with the general public), or you just want to take the scope out for a quick look, or something. Although they are generally the same type of scope, the 14 is much larger than the 8, and getting it into place for observing, cool down, and all that will be a bigger deal. You need a little scope for just those nights.

Second, you may want another scope to learn astrophotography on, or for looking through when the big one is taking pictures.

THird, you don't need the money all that much, and you would not get from the market what the 8 is worth to you.

Lastly, someday you will get older, and the 8 will be all you want.

Alex

August 18, 2003 12:43 PM Forum: Equipment Talk

building newtonian, 8 inch ? elliptical size?

Posted By Alex McConahay
Do a search for the program Newt, and use it to choose a size.

There is no one size for a diagonal. It depends on how much illumination you want on the field. If you want 100% illumination across the field, you will need a bigger diagonal. If you want just the center illuminated, you can get by with a smaller diagonal.

By the way--you are really doing the wrong thing, using an F4 and a big diagonal (and you will need a bigger diagonal for an F4) for solar system objects.

Alex

September 2, 2003 01:31 PM Forum: Film Astrophotography - Imaging and Processing

Mars photo question re: exposure?

Posted By Alex McConahay
Don,
Don't know your answer for the exposure--but it sounds like you are way overexposed. Remember--Mars is a daylight object! Maybe lots of power on it--but it is noon on Mars.

As for Walgreens or any other mass developer. You may have some wonderful photos there. Check the negatives. The problem is in the printing. They print as if it were a daytime photo--trying to make the sky blue. They may not know what an astrophoto looks like--and have no idea how to get your negative to look like one. It is not their fault--they are doing what they are trained to do.

Alex

September 3, 2003 02:09 AM Forum: Equipment Talk

shutter speed for Mars photos?

Posted By Alex McConahay
Don,

Go here and download Covington's exposure calculator. It will give you the answers you need, I think.

http://www.covingtoninnovations.com/astro/astrosoft.html

Alex

September 3, 2003 02:23 AM Forum: Celestron

Due Sheilds

Posted By Alex McConahay
You can make a dew shield from any thin foam, flexible cardboard, or whatever. (Last month I made a dew shield from two pieces of 8x11 paper, taped together, and then taped around the front of the scope.--it worked fine, but after six hours got soppy.)

My favorite material is a thin vinyl coated foam (about 1/8 inch thick). It is used in automotive upholstery shops to line doors. (It is abailable in auto upholstery supply stores.) I used a strip of Velcro to fasten it to itself in a big roll. And then, it slops over the front of the scope. It rolls into a very smooth tube when not in use.

Alex

September 4, 2003 03:49 AM Forum: Film Astrophotography - Imaging and Processing

Cygus - Finally a good one :-)

Posted By Alex McConahay
Hey, do I know that feeling!!!. And my first success was with the summer Milky Way in Cygnus, too. It's hanging on my wall in my office--with a few more by now.

Alex


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