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Topics - Cesar Lawhorn

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I got my new 10" Dob yesterday and assembled it last night after getting the kiddos to bed. It came with a laser collimator, so I needed to collimate that before using it to line things up in the scope. I came up with a super-simple setup.
1. Drill a 2" hole in a 2x6 (I'm sure a 2x4 would work fine; I just had the 2x6 already laying around).
2. Place the lumber in a vise or build little legs on it. I like the vise because it doesn't move or slide around.
3. Place a 2" extender tube in the hole. Mine happened to fit nice and tight; but if it didn't, you could probably wrap a strip of paper or something around the tube to keep it tight in the hole.
4. Place a 1.25" adapter in the extender.
5. Place the collimator in the adapter.
6. Aim the laser at a piece of paper on a far wall (mine happened to be abut 25' away) and mark the spot. Turn the laser a quarter turn and mark the spot. Do this until you have four spots. Just be sure your parts are all flush and tight, especially each time you turn the collimator. Otherwise, accuracy will suffer.
7. Draw a spot equidistant to the four spots (I put some cross hairs on the new center spot to make it a little easier to see).
8. Adjust your collimator's screws until it's centered on the new spot.
Quick, easy, cheap, and effective!

I want to preface this - I now have the gamut of scopes - a 8 inch Celestron C8 classic Orange tube , a 10 inch orion Dobson , a Meade 90 MM refractor goto , and last but not least a 4.5 reflector on a nice german eq mount - I read about people who have zambuto mirrors that have certain strehl ratios and ooh and ahhh about being able to go to 300x magnification-my question to you with more experience - I cant seem to go above 120X or 150X in magnification without things going soft. Chasing perfect scope I can do - but in the end where or what do I fix - my eyes are 55 years old - I don't see very good - I don't think I can improve my C8, on the refractor I cant improve it - but the things I can change is the 10 inch orion Dobson - it is factory made - is it worth getting the 10 inch mirror refigured , would it improve my lot in life ? What about the secondary - how important or quantam leap is a secondary with 99% reflectivity and made from quartz will improve my lot in life?
Is a 500 dollar eyepiece going to significantly improve my views ? Inquiring minds want to know...

Why did you choose an alt-azimuth mount rather than a equatorial mount? Are Equatorial mounts becoming obsolete? Thanks to you all.

Beginners Forum / 6" or 8" newtoanian ?
« on: January 01, 2018, 12:24:06 AM »
Hi Everyone,

I have a Celestron CG5 Advanced GT mount.

I currently have a 100mm F6 Orion refractor with a focal length of 600mm. I am thinking of buying an 8" or 6" newtonian OTA for visual use, mainly to get some nice view of planets, and hopefully some bright DSO's. I live next to a city, so I have a significant amount of light pollution.

Do you think it is worth going with an 8" OTA for my needs? I am not sure how much difference there would be viewing in a 6" vs. 8" newtonian.

Any thoughts or suggestions would be greatly appreciated!
Or,, should I go nuts and buy a 10" ? haha

Reflectors Telescopes Forum / Thinking about explore scientific 16 dob
« on: December 31, 2017, 07:48:27 AM »
How is the mirror cell, and does it properly support the mirror?
How do you like the front primary collimation knobs and tool?
Does the scope hold collimation well when moving the scope from horrizontal to vertical? 
Does the focuser handle heavy eyepieces and/or paracorr without sagging? I would also be getting the counterweighg set.
How is the secondary holder and side adjustment system? Does it pinch the secondary? Is it simple to adjust for collimation?
Any issues with the scopes I should be aware of? I know the initial run had problems but I have read that they fixed them. They look like an awesome scope for the money, and I understand they wont be perfect without any flaws in this price range. My main concern is how the structure performs.

Northeast Astronomy Forum April 9 & 10, 2016

I am about 8 months into this hobby so everything is new to me. What can you tell me about NEAF? I live on Long Island. Thisappears to be about a 60 miles away which is very workable. I have read the web site and this looks pretty interesting but I am interested in hearing from people who have gone to this event in the past to hear about what you thought.

What did you really like?

If I were to go, what do I want to be sure not to miss?

What to avoid?

Should I bring a telescope with me?

Is this kid friendly?

Bargains galore?

Should I plan to stay over for night time activities?

My wife is not interested in astronomy. Is there anything for her to do at the event or in the area?

Inquiring minds want to know.


I'm brand new to amateur astronomy, having just acquired my first scope - an 8", f6 dob (XT8 Plus, specifically). I've taken it out every clear night and I'm already sure that this will be a hobby I will be investing some time (and money) in. I've spent some time reading through these forums, and have read through two highly recommended books ("Nightwatch" & "Turn Left at Orion"), but there are some things I could use some further advice on:

1. Light pollution: I live in an urban environment (Alameda, CA - basically downtown Oakland) and the light pollution is awful. I have 3 young kids, include a 1 month old, so my ability to get away from home to seek out dark skies will be limited for the foreseeable future. I understand that many deep sky objects will remain out of reach from my location, but I still want to seek out all the open clusters and multi star systems and any other bright objects that I can from my own backyard. Considering my gear, and that I have no GoTo technology, I'm reliant on star hopping to find my targets, which is quite difficult with my severe light pollution.I had considered getting an extreme wide angle eyepiece at low power with which to break through the pollution to navigate the skies for star hopping purposes.Is this a feasible solution? Perhaps coupled with a broadband filter?Any other advice on star hopping in severe light pollution without GoTo technology? Also, can you please recommend a resource for light pollution maps?

2. Filters:I'm considering purchasing two different filters, a broadband filter to dampen light pollution (noted above - although I question how helpful it will be), and a narrowband filter for nebula viewing from home and on rare occasions when I can get away from the city. Regarding the narrowband, I've read great reviews on the DGM NPB, so that's currently at the top of my list. With that in mind, I'd rather not pay the full $150, so I'm mulling the idea of getting the "cosmetic 2nd" discounted piece from Amazon (, but I'm concerned about the fact that the flaws include "cosmetic flaws, such as pinholes, sleeks, or light scratches". Are these flaws significant when it comes to filters?Or should I trust DGM when they say "flaws which have zero impact on optical performance. Spectral characteristics are the same high quality as our first quality filters and side by side performance is indistinguishable."

3. Eyepieces:There's so much information out there on eyepieces, it's difficult to settle on which eyepieces to target next. The XT8 Plus comes with an Orion 10mm plossl and 28mm "Deep View". The plossl seems well enough for now, but I don't feel that the Deep View provides enough FOV for a lower power eyepiece, so I think a low power, wide angle eyepiece will be my next purchase.With that in mind, any recommendations on the ideal "True FOV" to shoot for low power viewing? I know 2"+ will be necessary to take in all of thePleiades and Andromeda (for example), but is 2" considered overkill, or is this a good TFOV to shoot for? Any other eyepiece advice you can provide regarding building a strong initial eyepiece set would be helpful as well (considering mid to high-tier options).

Thanks a lot!

Mounts Questions & Expirience / CDK 24" - 10Micron 4000HPS?
« on: December 26, 2017, 09:31:31 AM »
Fantastic morning,

An observatory question:

I would love to ask the most experimented with all the 10 Micron mounts when the 4000HPS german mount would be able to carry a CDK 24" with a few additional gear: a Takahashi TOA 130, 2 CCD's, filter wheels...

The OTA (CDK24) is about 109kg.

What are your thoughts?

Thanks so far.

Light Pollution Topics / Outdoor lighting war
« on: December 24, 2017, 08:03:34 PM »
Are there any lawyers on CN that enjoy astronomy.  I've got a neighbor that has gone berserk with brilliant outdoor lighting.  I asked him if he'd turn off the spotlights and he put up more and aimed them in my property.

I thought a lawyer would have some successful legal precedents they may share.  Thanks, Alan

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