Conditions to a Beginner

I've recently purchased an 8" Dob and im certainly definable as a beginner astronomer. Pointing my scope up to where i know DSOs are i see absolutly nothing. My sky is terrible admitted but when i look at m42 i see no structure. Is the limiting visual magnitude distorting the image of the Nebula. That is to say is limiting magnitude simply whether or not you can see something or does it also affect the amount of detail observable in that object?

Megez is visable with much straining of my eye.

Simply put, if the skies are not too dark, you will not see much structure in anything except perhaps solar system objects, some star clusters, and doubles.

The problem is that you simply do not get much contrast in light polluted skies. All the sky is aglow, and so no matter how bright the bright parts are, the black parts are gray. And thus there is not too much contrast. You are dealing with shades of gray instead of blacks and whites.

Now, there could be lots of other problems--collimation, focuser travel, and a bunch of other dumb things. But most of these could be fixed and you would still not have great views of those objects....

However, you still have lots of things to do until you can get to a dark sky, so enjoy that scope.

Alex

Hi Zack,

So many questions come up in reply to your post, particularly if we don't assume anything: First off, do you know if your 8" dob is adjusted (collimated) correctly? That would be critical particularly if it's a fast scope, say f/5 or lower. Next, what size eyepiece are you working with? It would be good to start a search for DSOs with with a wide angle lens. Then once you acquire a target object in a wide angle field, center it and change to higher magnification as desired. How are you focusing? Are you racking the focuser back and forth on both sides of the sharpest view of single stars, and gradually narrowing it down to the sharpest view? How are you going about finding your DSOs? More specifically, how do you know when you're on M42, for example? What kind of finder do you have, and have you made sure to sync up your finder to the scope so they're both pointing at the same place in the sky?

At this point, it doesn't sound like limiting magnitude is your problem. Answer the questions above, and let us know the results.

Good luck,
Howard K

Just take a shotgun to those pesky streetlights! 8O

Just kidding, of course. You will definately have better luck somewhere a little darker. You might try looking for a place with less light pollution here: http://cleardarksky.com/lp/SanFranCAlp.html

White is the worst, followed by red, orange, yellow, green, blue, gray, and then black.

If you have a car, you could get to some dark sites not too far away. You might even see some improvement by going somewhere away from the lights, say a park (the zoo, the Presidio, etc.)

Finally, contact your local astronomy club and find out where the good places are locally. The sidewalk astronomers in SF are holding a clinic on how to use your telescope this weekend:

http://sfsidewalkastronomers.org/newsarticles/clinicmar