Posts Made By: Greg Shaffer

Exported the pptx file as a jpg....should be able to upload the specs now....

Have heard back from 6 requests for a quote now, one turned it down and 5 are working it up. Going to be interesting to see how much variation there is in the quotes.

So the 1st of 3 known to be willing to quote (based on communications) out of about 9 houses came in today, about 5 or 6 turned it down or have not responded.

I know I am getting quotes from 3 sources so far, Esco Optics, R L Cumberland and United Lens not in order of quoting.

The 1st quote is $1150.00 uncoated $1910 coated. Obviously coating is quoted based on a solo run and I have inquired about waiting on them to do a production run to lower the cost....another $150 for interferometer testing.

Leaving out the coating cost this is actually a little better than I was expecting so it looks like this is going to happen

I may actually forgo coating since I am mounting the window at about a 3 degree angle to the light path ghosting wont be a factor and I doubt a 3% gain in light transmission would even be noticeable.

Just heard back from a 4th company LaCroix Optical out of AR today that they will be providing a quote next week so that's one in and three more potentials so far.

As John pointed out it was high time I updated this thread....

After discovering that the lenses were reversed and sending it off for interferometer testing and discovering it was badly spaced on top of being reversed we made a new spacer for between the lenses out of ABS and finished the physical build of the scope. Have been using it for a few months now and it performs even better than I hoped it would.

After all the measuring for testing and validating the design, two different sources confirmed that spacing the lenses to .664 would cure its issue with excessive blue fringing,it was caused by an issue with R3 not being to design spec on the radius.

We made the spacer out of a block of ABS on the lathe....Once we got it under the stars we knew right away that the issues were over. Both sources (Nu-Tek and Mike Jones a optical engineer with Lockheed-Martin) were in agreement the change should make it perform per Remer's original prescription and they were spot on, I really don't believe it could be any better. Saturn and Jupiter are just flat out amazing in it with no perceptible fringing at all when using binoviewers and just the barest hit of blue fringe with single EP's on Jupiter.

The R3 radius by design was supposed to be 43.0" and it was actually 42.040" for a deviation of 0.960" which is significant as it represents a 2.23% variation from the design spec and was resulting in a lot of visible blue fringing. The new spacing cleared that up nicely.

Pic of ABS spacer....we cut baffling ridges into the ID of 0.035" deep and 0.050" wide given the distance between the lenses is now over 1/2" I was concerned with reflections.....it musta worked

Greg Shaffer said:

Been gathering up the parts for sometime now and have everything on hand now except for 9" tube itself.

Been thinking on the best way to construct the baffle system and it hit me like a ton of bricks yesterday.....

Use carbon graphite arrow shafts cut to the proper lengths to space out the baffles properly, can cut them to lenght, glue in the inserts, drill holes in the baffels and simply insert them sandwiched between the shafts, three shafts per section, ending up with an all in one assembly that I have just slide into the tube and anchor at each end of the assembly.....super lightweight, strong and already black.....


Based on my calculations I will end up with 5 baffels.....using thin aluminum sheet for the baffels themselves.....I dont see any reason it wouldnt work and work well.....any thoughts?

Thanks
Greg

Ernie Spragg said:

hi - is there anything in the Astromart rules that limits the contents of the statement on our profile page? Are we free to make political / religious statements there - statements that have nothing to do with amateur astronomy - that might offend other Astromarters who are not of the same faith / political persuasion / opinion, or who feel that those opinions are better expressed in the forums, if they must be expressed here? Ernie Spragg

Have a look at the rules http://www.astromart.com/aboutus/terms.asp

Of course we are all here under the auspices of Herb's ability to put up with us. If he doesn't like it the answer would be no regardless of what the rules say because he can change them

Marcelo Barbosa said:

Ok. We have all seen and read the 2 or 3 reviews on this scope. I'm about to take the plunge and would be interested to hear any final and additional opinions on the rig. I've owned the following: Tasco 60MM refractor (yeah, I know, had to get something for Haley in 1986...), Meade 8"SCT, Celestron 9 1/2 Equatorial, 11" CPC, and now am ready to go BIG.
Yes, I've had a few scopes. I need more aperture and although I have light polluted skies (red-orange), I am not willing to carry 140lbs to my outreach events. I do have access to a dark site 25 mins away, so portability helps. As far as mirror quality, I can compromise some as long the requirements above are met (aperture, weight).
Lightbridges and skyquests are nice, but bulky. Explore Scientific's light dob has been in the works forever and I can't seem to get a lot of feedback on it. Obsessions's UC at $5K+ are prohibitive, at least at my budget.
So, is the UL 16 at $2k a good choice?

Marcelo.

I wouldn't go there myself.....but that's me. I would however recommend you give a hard look at something along the following lines.

For a mirror deals on the meade 16" f/4.5's pop up on AM from time to time either original like this one http://www.astromart.com/classifieds/details.asp?classified_id=881403 $600 to $800 or refigured as this one may be. http://www.astromart.com/classifieds/details.asp?classified_id=887299 at $1250

Then for something to put it in one of the DobStuff kits available at various stages of completion. It would run you a bit more though not terribly much....See here http://www.dobstuff.com/pricing.htm

It wont be instant gratification like the UL16 would be....but over the long run I think you would be happier with the end product. Check out the pics of his truss style scopes....they are indeed still light and I have used one of them and found it to be in great in use and design.....

Dwain Mayer said:

Hi,
I've renewed my subscription (twice, I think) but I still get:

Your support has expired or your current support level does not allow you to get classified emails. Only supporters can get classified ads emailed to them.

Can someone tell me what I'm doing wrong please?
Thanks
Dwain

Not positive but I believe just renewing your yearly $15 member fee does not get you access to that....that is only for supporters and the time it gives you that access is based on what level of support you choose. Though if I recall correctly a new sign up who only joins with the $15 yearly fee does get 30 days access to new ads by emails as a promotion. Pretty sure about the 1st part but I could definitely be wrong about the 2nd part.

Bert Katzung said:

I tried to post an ad in the classifieds today but it won't let me list my email address or links to the websites with images. Most of the images I would post are on my hard drive and I would like to upload those. How do I do that and how get my email contact info in the ad?
Thanks,
Bert

It is not allowed to put personal contact info in an ad, including email addresses. If someone is interested in buying they reply to the ad via astromart and you are sent an email via the email address you have on your AM account. Once you have received it when you reply it will go directly to them and then you can converse via each others own emails. The 1st communication must however go thru the AM system.

As for uploading images you are prompted to upload them as you enter the ad as the other guy described. Putting links to another site as you described is also not allowed. If you don't have a copy of the pics on your own computer simply get them off the other site so you can directly upload them off your computer during the ad entry process. Also note there is a per image limit on filesize, I believe it tells you during the process what that is....if they are over the limit it wont accept them.

Russ Carroll said:

http://nypost.com/2016/05/05/playing-the-press-and-the-public-for-chumps-to-sell-the-iran-deal/

I'd rather have the destruction of the Republican party on my hands than the Iran deal, so at least Ted has that going for him.

(I just CAN'T stop jabbing Lyin' Ted 8) )

Obviously....kicking a man when he is down is always great fun right?

Ted Clutter said:

I am new to Astromart. I posted an ad for my pair of 8x30 CL Swavorski binoculars, then receive a threatening and lengthy email telling me I am in violation. What is this? The binoculars are mine. I posted a brief description and a purchase price. How am I in violation of anything?????? Then I look, and my ad has been taken down. So I repost it. Then I am threatened with being kicked out of Astromart. No explanation why. WHAT IS GOING ON? [SIZE="Large"][/SIZE][COLOR="Blue"][/COLOR]

A "lengthy" email? I am reasonably confident Herb has never sent a lengthy email in his life LOL

There are a number of reasons for which an ad will be taken down. 1. You posted personal contact info in the ad. 2. You stated you were selling them for someone else. 3. You are running the ad simultaneously on another site (particularly ebay). Those are just the three that come to mind right off....

You might refer to the terms of service (TOS) and make sure your ad doesnt violate any of the conditions set forth therein... http://www.astromart.com/aboutus/terms.asp then repost it.