Up Late
journeyman
Reged: 12/06/07
Posts: 9
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This is my first post ever here and I am hoping some one can enlighten me, as to if what I am experiencing is a scope problem or if Astronomy Magazine just has my hopes set too high.
I got a small 3 inch refractor scope a couple of years back and it got me interested in star gazing. It found it clumsy to use and soon discovered its limitations - but it got me going.
This past May, I purchased a Zhumell 8 inch Dobsonian reflector. I had several problems right away. I read a lot of reviews about it and knew about the 4 nuts that could come loose so I was expecting that. (And they did come loose after just a few uses).
However it never focused very well right out of the box. I read that if it never focused well it may need to be collimated. It came with one but it never fit in the eyepiece opening very well (I found a fix for that after a while). When I went to adjust the mirror I discovered that one of the adjustment screws was missing it's tension spring and this seemed to be causing my problem. I called Zhumell and they sent me a replacement spring in the mail. I installed it and re-collimated my scope and it seemed to work pretty good but my I had problems with the 9 mm eyepiece that came with the scope - it just wouldn't focus well.
I decided to purchase the eyepiece and filter kit. I am very happy with this kit. I discovered using these new eyepieces that there definitely was a problem with the 9 mm eyepiece that came with the scope because the new 12.5 mm and 6 mm eyepieces that came with the kit, worked way better. I started to play with the 9 mm eyepiece and discovered that the two lenses did not line up well. I loosened the socket holding them together and gently tapped it on a hard surface and the two pieces fell together. It worked better after that.
I found many Messier objects with this scope but haven't found anything dimmer in apparent magnitude than the Ring Nebula - even when I did find it, it only looked like a small smoke ring.
What I perceive as another possible scope problem is this:
- Even though I can find deep space objects, I can not get the inner planets to come into focus. When I first saw Saturn in May, it was a blurry ball with rings, however I could see Titan (as a small dot).
When Jupiter showed up I could clearly see it's four moons, but the Astronomy Mag indicated that people with small to medium sized scopes should be able to make out the big red spot. However all I could see was another blurry ball with two faint black lines near it's equator.
Now Mars is here. Again the Astronomy Mag says, and I quote, "Still, Mars will show lots of detail through small and medium-sized telescopes, and will appear stunning through large scopes."
I saw Mars for the first time this year just the other night. Again it was just a fuzzy ball - a bright orange fuzzy ball, but a fuzzy ball all the same - not much detail.
That same night when Orion came into view, I saw the Great Nebula - what a great view - it was cold and crystal clear that night and the nebula looked fantastic.
My question is, am I expecting too much from my views of the inner planets ? I do live in the city, but I saw a lot of globular clusters through out the summer, so I am confused - do I have a scope problem that is preventing me from getting a crisp look at the inner planets or is the best I should be expecting is for them to look fuzzy ?
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werewolf6977
Lord High Smasher
Reged: 12/15/03
Posts: 9034
Loc: Hanover, Ohio
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Are you letting your scope cool enough? It'll take about an hour or more if ou live in Northern climes. Also, at what angle above the horizon are the planets when you observe? If they're less than 45 Deg above the horizon, you will be observing through more atmosphere then if you give them time to climb towards zenith. In fact, if you can observe close the zenith, you'll be amazed.
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Pete
6" Apogee/LXD55
Starhopper 6" Dob
Spaceprobe 130EQ
Black C8 OTA
WO Zenith Star 66 Patriot Edition
Sun Pak Pro 7500 Platinum Edition
8X42 Bushnell H2O Porro
7X35 Tasco
10X50 Nikon Actions (Type 7)
15X70 Skymasters
Dell Inspiron Dual Core 531s
"For those who fought for it, Freedom has a flavor the protected will never know"
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firestar
Born to be Mild
Reged: 10/18/06
Posts: 3942
Loc: Cleveland Ohio USA
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Welcome to cloudy nights!
Seeing conditions have a lot to do with what you see.
Try to view at zenith,if you can.
Use stellarium to plan your session,so the planets will be high overhead.
I dont think jupiter ever climbs very high in the sky though.
You'll need to collimate your laser tool.
Get yourself a cheap miter box at home depot.
Set your laser tool in the v shaped grove and focus on a target on a far wall.
Rotate the laser,and make sure the beam of light stays on the target.
If it moves around,make adjustments with the hex head screws,so that it stays on target.
Then set the laser in your eyepiece holder,tighten the setscrew,and collimate the scope at a 45 degree angle,being careful not to drop any tools down the ota!
You will probably only need to tweak the secondary mirror if your lucky.
Be sure to let your scope sit out a couple hours and cool down.
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Eastlake Ohio
Lots of cheap Asian glass  
Antares 12" Dob,Antares 8" Dob
Meade 8" SCT, Celestron C8 SCT
Zhumell 152 mm F8,Antares 127 mm f9.4
Orion short tube 90 F5.6,Celestron 80 ED F7.5
Imaging Source DMK 21AU04 ccd camera
Stellarvue bv3's with 32,26,23,21,9 mm pairs
Olivon 42,35,28mm,siebert 21,12.5,7mm,GSO superview 20mm,Meade swa 13.8mm,Hyperion 13mm
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katodog
Supreme Grandmaster
Reged: 03/31/06
Posts: 2619
Loc: Carol Stream, Illinois
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While what you describe sounds like you may have a problem, it's also very possible that you are setting your hopes pretty high, and what you expect and what you get are two different things.
If you got a great view of M42 (the Orion Nebula), then I'd probably have to rule out collimation. Jupiter this year has been a rough target, and rarely showed me any good detail visually through my 12" scope. It's always a hard thing to get good detail on if it's not too high above the horizon. Saturn, on the other hand, should clearly show the Cassini division through your scope, and a good separation between the rings and the globe.
Now Mars, that's a tough one. You may or may not see detail, that depends on what you're using to view it. As an example, through my 12", typically what I get is a big orange ball visually. I have only seen detail through stacking frames of a video, and processing. That's not to say that you won't see detail through your scope, but I think the conditions have to be really good, and you might need a filter, to bring out detail.
You could be experiencing bad skies. Sometimes when it looks nice and clear to our eyes, it's a different story through the scope. You have to remember that the scope magnifies everything you aim it at, this includes heat waves from rooftops and chimneys, dust in the atmoshpere, etc.. It's possible that you're not getting good views because of poor skies. Higher power will do this to you. The higher in mag you push the scope, the more and more bad sky you will be seeing.
Basically, there's a lot more to telescopes than meets the eye. Even pros sometimes succumb to the trials and tribulations of a bad night here and there. I'd have to say that if you saw M42 pretty good, then there's nothing wrong with the scope. You may just be experiencing bad seeing.
Keep at it, and try different eyepieces to see if it's simply too much power for the night. You may find that it's the sky being difficult, and nothing more.
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The only stupid question is the one that goes unasked
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Up Late
journeyman
Reged: 12/06/07
Posts: 9
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It was a cold night. I was out for about an hour or so. The scope comes with a fan and I did have it on. The angle was about 30 degrees to the horizon when I first looked at Mars and then about 35 to 40 degrees about an hour later, then I just got too cold to stay out.
That said, it did seem a bit clearer on my second look. It will be interesting later this week as it is suppose to clear up by Friday. I will get a second chance and I may wait till later at night so Mars can climb a bit higher over head.
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Up Late
journeyman
Reged: 12/06/07
Posts: 9
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I live in Victoria, BC Canada (on Vancouver Island). Jupiter never got very high above the horizon so that may be why it was blurry.
In May, when I was looking at Saturn, I could make out a black line or space in the rings, but the planet itself never seemed to get crisp. Saturn wasn't quite over head but it was well away from the horizon. It's hard to remember now how sharp it was compaired to Jupiter. I'll have to wait several months for it to return.
When you say I should adjust my laser tool - do you mean the collimater itself ? If so, I wasn't aware that thing could be off target.
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ColoHank
Carpal Tunnel
Reged: 06/07/07
Posts: 1653
Loc: western Colorado
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You say you got the Zhumell eyepiece and filter kit, but don't mentioned having used any of the filters. Assuming that you have decent seeing, by all means experiment with different filters to enhance your planet viewing experience. When conditions are favorable, and with the proper filter, you should see more detail on Jupiter than just the two gray lines near its equator.
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Questar 3.5 standard - pyrex and BB coatings
Powerguide II
8mm, 12mm, 16mm, 24mm and 32mm Brandons
Homebuilt Galileo scope and very large and ugly homemade tripod
11 X 56 Oberwerk binoculars
other odds and ends, including iPod Touch (and now iPad, too) with StarMap Pro (what a marvelous combo)...
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"Nothing exists but atoms and empty space. Everything else is opinion."
Titus Lucretius Carus 99-55 B.C.
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Up Late
journeyman
Reged: 12/06/07
Posts: 9
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Actually I did play with the filters a bit. I liked the way that Saturn looked with the #12 yellow filter, it seemed to be sharper.
Venus was better when I used the Crystalview Moon filter and surprisingly interesting when I used the #23A Light Red.
I tried a couple on Jupiter too. The #56 Light Green made those two dark lines stand out a bit better but I still could not make out the spot.
I never tried any filters on Mars yet. I also what to try the #82A Light Blue on the Andromeda Galaxy. There are just so few clear nights here, that once I get outside and start looking for the new sights, I don't seem to find the time to play with the filters. I guess it is a matter of getting into the habit of using them.
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plav1959
sage
Reged: 05/10/07
Posts: 270
Loc: Central Florida
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Just a suggestion - do you belong to a club? There is a RASC branch near you :
http://victoria.rasc.ca/
I found a club near me when I first got started. Best investment I've ever made in astronomy. Most clubs have members with a wealth of info that are very helpful. You could compare views through your scope to someone who has a similar scope, swap out ep's etc. to narrow down any problems. Could be seeing, collimation or any number of things. And yes, laser collimators are notorious for being out of collimation themselves. As posted above, however, it is an easy test to check laser 's collimation.
Hope that helps,
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Paul
16" Starstructure f/4 w/AN-SC and Zambuto optics
Lunt LS60THaDS50_B1200_CPT
Orion 10" Newt
Orion 8" imaging newt
Explore Scientific ED127 CF Apo
Astro-Tech AT65EDQ
Celestron CGEM mount
Celestron ASGT mount
Mallincam Xtreme, Hyper Plus
Denk II Supersystem
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rmcpb
Carpal Tunnel
Reged: 11/16/04
Posts: 1606
Loc: Blue Mountains, NSW, Australia
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If you are going for the higher power views of planets then wait till the planet is at lease 45 degrees above the horizon otherwise the extra layers of air turbulence will wreck your views.
If you are in a light polluted area one of the problems with light pollution is that it reduces the contrast of any images you will see. Planets tend to have low contrast to start with, especially Jupiter, and Mars is always a challenge visually.
If you have your scope collimated, cooled and is as dark a place as you can manage then you should get reasonable views of the planets with it. My 8" scope is the same type (GSO) and it gives me fantastic views but then I am blessed with dark skies.
Just take your time and try some of the light pollution tricks like a light/dew shield, wear an eyepatch and use an observing hood.
Keep looking up 
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Rob Browne
8" & 13" Dobs
Equatorial Platform
Couple of Panoptics and a handful of BO/TMBs
9x60 binocs
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firestar
Born to be Mild
Reged: 10/18/06
Posts: 3942
Loc: Cleveland Ohio USA
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Yes the laser collimator has adjustment screws.
Here is a picture of a miter box.
Its a simple tool with a v shaped grove.
Lay your laser collimator in the grove and project the beam on a wall.
The laser beam should stay in one spot,not move around in circles as you move the laser tool.
The laser collimator should be parallel to the position of the saw in the picture.
collimation video
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Eastlake Ohio
Lots of cheap Asian glass
Antares 12" Dob,Antares 8" Dob
Meade 8" SCT, Celestron C8 SCT
Zhumell 152 mm F8,Antares 127 mm f9.4
Orion short tube 90 F5.6,Celestron 80 ED F7.5
Imaging Source DMK 21AU04 ccd camera
Stellarvue bv3's with 32,26,23,21,9 mm pairs
Olivon 42,35,28mm,siebert 21,12.5,7mm,GSO superview 20mm,Meade swa 13.8mm,Hyperion 13mm
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Jim Rosenstock
Postmaster
Reged: 07/14/05
Posts: 6543
Loc: MD, south of the DC Nebula
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Hang in there. You're doing OK!
Since you're getting good views from a number of objects, I'm guessing your scope is pretty much OK. The objects you're having difficuulty with....well, actually, they're kind of difficult objects.
Mars has, for many decades, been our most famous planetary cousin....y'know, the canals, "The War of the Worlds", etc. etc. But the truth is, Mars takes a lot of effort, patience, and waiting to tease out little bits of detail. It's not very big--smaller than Earth--and pretty far away, even when it's at its closest. With experience, you'll learn to see low-contrast detail better, and from time to time (if you go out enough) that magic night (or hour, or minute, or even a few seconds) will come where all of a sudden you're making out a LOT more detail than usual. But, it takes work. Filters can help, too.
Jupiter: it's a big, impressive object, for sure. But its details can be kinda low-contrast, too....and as others have noted, it has lately been in a part of the sky that never gets very high for us northern hemisphere observers, so there's the issue of looking through lots of air at it....also, the Great Red Spot has, in recent years, not been very red....it's still a big, prominent feature, but the color contrast is very, very subtle.,..
Venus, an inner planet, never gets really high in the sky either, so there's the "too much air" issue....it's tremendously bright as well, so scattered light can be a real distraction....try a Moon filter or something else to cut the glare (some folks even use sunglasses!).
Don't despair. As you "learn to look" and as more hours of observing give you more time under really good observing conditions, you'll be perceiving more and more details.
And, the views we really struggle to get....
....are the ones we remember foreverr! 
Clear skies,
Jim
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QUESTION AUTHORITY!
"errr....sez who??"
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aarons
member
Reged: 08/30/07
Posts: 55
Loc: Wet Coast, Canada
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We're in your neighbourhood, up_late, and have a similar 'scope to yours. We've found that it takes a couple of hours for the 'scope to cool to the point where high power is half possible. Also, both the transparency and seeing haven't been very good this fall when we have had the chance to get out and look. Mars has looked pretty featureless and wavy. Apart from good collimation and cool-down, I wouldn't worry too much about your equipment - apparently it just takes patience and persistence to get good views at high power. Good luck, and here's hoping we get some good clear skies soon!
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8" f6 Skywatcher Dob
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Dan Hester
super member
Reged: 01/06/06
Posts: 131
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If, after all the advice above, you still have issues, you might check for signs of secondary astigmatism. The sticky stuff that they use to supplement the attachment of the secondary mirror to the holder warped mine.
If the shape around a bright star is elongated in one direction on one side of having it focused and then turns 90 degrees on the other side of the focus, that is a pretty sure sign.
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10" Zhumell Dobsonian
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docmusolf
Out of Africa
Reged: 09/06/07
Posts: 93
Loc: port austin, mi
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If you are confident in your collimation you may have the same issue that i have. The mirror is not cut to the correct focal lenght. I needed 1 inch extender for mine so that I could get it to focus correctly. Try to pull the eyepiece ut a bit from the focuser and then try to refocus. If this fixes the issue then buy an extender for 20 bucks and enjoy better views.
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stefanj
Carpal Tunnel
Reged: 11/15/07
Posts: 1769
Loc: Western New York State
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Don't give up hope!!! Planets are difficult- and there seems to be a lot of waiting for that "breif" glimpse that makes it all worth while.
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Life is a circus- and I'm stuck in the FREAK TENT
If these are blue- it means the moon is full!
Meade ETX 90RA w/ tripod
Meade AZ 70 (now solar)
Meade DS 2130 AT
Zhumell 10" Dob
Simmons 10x50 Binoculars
GLPx8
LPI
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Dylan Gladstone
scholastic sledgehammer
Reged: 08/05/07
Posts: 992
Loc: Connecticut, USA
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Quote:
The scope comes with a fan and I did have it on.
Were you viewing with the fan running?
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Orion SkyView Pro 127mm Maksutov
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thj
professor emeritus
Reged: 02/07/06
Posts: 676
Loc: San Tan Valley, Arizona
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Many have mentioned this before but here's some of my thoughts ...
Quote:
I got a small 3 inch refractor scope a couple of years back and it got me interested in star gazing. It found it clumsy to use and soon discovered its limitations - but it got me going.
That's always a good thing
Quote:
When Jupiter showed up I could clearly see it's four moons, but the Astronomy Mag indicated that people with small to medium sized scopes should be able to make out the big red spot. However all I could see was another blurry ball with two faint black lines near it's equator.
Jupiter was really in a bad position this last summer. It was never really high enough in the sky for really great views.
Quote:
Now Mars is here. Again the Astronomy Mag says, and I quote, "Still, Mars will show lots of detail through small and medium-sized telescopes, and will appear stunning through large scopes."
I saw Mars for the first time this year just the other night. Again it was just a fuzzy ball - a bright orange fuzzy ball, but a fuzzy ball all the same - not much detail.
The biggest thing that I noticed on Mars recently is that it's too bright without a filter; at least that's my impression. I have a 10" scope and without a filter there's a lot of glare. I use some color filters but even my variable polarizer already improved the views and the detail.
Quote:
That same night when Orion came into view, I saw the Great Nebula - what a great view - it was cold and crystal clear that night and the nebula looked fantastic.
Were you able to resolve individual stars in the Trapezium?
The main issues with planets are seeing and scope cool down. Not much you can do about seeing but the cool down could be a big issue. On a recent "cold" night here I had the scope out for 3-4 hours, observing on and off and the scope never adjusted to ambient temperature. It seemed that it couldn't keep up with now quickly the air was cooling. The mirror boundary layer never went away and Mars looked like a fuzz ball with no detail whatsoever the whole time. Since you have a fan this might not be as much of an issue but something to keep in mind. Next time you see a boiling Mars and it's high enough were you would expect it to be better check to see if there is a mirror boundary layer. Just look around this forum or ask if you need any help with that. As long as you have a boundary layer your planetary view will be less than ideal.
edited: boy I need to learn to spell
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Thomas
(My Astro Photos - fairly outdated  but I'm working on it)
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N 33° 09' / W 111° 33' (San Tan Valley, AZ - Johnson Ranch)
Orion 10" Newtonian
Orion 102mm F/7 ED
Atlas EQ-G
Stratus 21/13/8/5 mm EPs
Orion 32mm Q70 EP
Plössls in many shapes and sizes
Canon Digital Rebel XSi (a.k.a. 450D)
Edited by thj (12/07/07 10:53 AM)
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stefanj
Carpal Tunnel
Reged: 11/15/07
Posts: 1769
Loc: Western New York State
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This is a great point- as the temp drops the mirror has to keep up- and may never get to temp-
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Life is a circus- and I'm stuck in the FREAK TENT
If these are blue- it means the moon is full!
Meade ETX 90RA w/ tripod
Meade AZ 70 (now solar)
Meade DS 2130 AT
Zhumell 10" Dob
Simmons 10x50 Binoculars
GLPx8
LPI
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Up Late
journeyman
Reged: 12/06/07
Posts: 9
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Hey Docmusolf
I'll give that a quick try next clear night.
Tks
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