Mar's Digital Photos (was Re: 900 GTO Initial Report.)


Jun 21, 2001

 


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#2857 Jun 21, 2001

Last weekend I took the 900 GTO out for it's first spin. It's carrying a

130EDT vintage 1993. Picture of it and my hand held afocal mars images are

here:

www.fototime.com/inv/466AE460997F4E5



Setup went very smoothly. I also received a polar scope. What a PITA it's

reticle was to align! Adjusting it is easy enough. I mean once the dang

thing is in the RA axis... 'hello!' :) The RA axis is pointed at the sky! :)

Getting some distant telephone pole in the center to align the reticle took

disassembling the altitude adjuster bracket as well as putting two concrete

block under the SE and SW portable pier legs. All this to tilt the thing far

enough to the horizon to get the reticule on a distant marker. I'm sure I am

stupid and just missed some easier way (in the field?). Okay. All that

worked once I did the tilt thing.



Then I thought I had all the cords I'd need to run the mount. Uh oh... The

AP 12vdc cord uses a female cig lighter connector.... hmmmmm... and I have

what to connect that to my 7amp power supply? Nothing? Great! =:0 Well all

is well that ends well, as I had a cord with battery clips on one end and

the AP mount jack on the other. The jack was a little loose and had no

locking collar like APs But it worked. And yes once during the night I

kicked the cord off the power supply since it was secured only by the clamps

clamped onto the supply's output lugs, but it got me through the night.



No lockups. None. No overloads. None. In fact even with the 18 pound counter

weight all the way up the shaft, it's was still slightly out of balance. But

if I understand correctly, you want the RA slightly out of balance to

maintain the gear/worm contact at all times anyways.



The pier was easy enough to set up and more importantly at 2:30am in the

morning, take down and pack back in it's box. I am going to create some

bubble pack 'socks' for the pier legs using the copious amounts of bubble

pack the mount came with. Then I can put each leg in a sock, put them in the

middle of the pier, and the pier in the box. Until I figure out something

better, I'll reinforce the pier shipping box and use it to carry the pier

and legs.



The mount was a no brainer to setup other than the above mentioned polar

scope reticule alignment contortions. And the Pelican 1650 case worked fine.

I had another small 'camera' style metal case with dividers that held all

the other various cords, mounting plate screw packets, and controller. The

lid held the manuals (which I read several times).



Using the Polar scope tracking _visually_ was fine. Pointing? So-so. A few

iterations of the N. Polar Alignment really didn't help. But using the 2

star alignment did. However a slew to say M15 on the eastern horizon,

followed by a slew to Mar's on the western side of the meridian, did not

place Mars in the 1/4 of a degree FOV of a high power eyepiece. But well

within a 1 degree FOV of a low power ocular. I'm sure it's just a alignment

error on my part. I'll have it out again Saturday (6/23/2001) and try the

Goto assisted drift alignment. I understand it's a fast procedure once you

get used to it.



Otherwise, what's to say? Oh, I know. Funny but the rap test? It's takes a

long time to settle down 7 or 8 seconds. BUT it's rock solid focusing and

such. I suspect all that metal 'rings' when rapped hard. But it takes a good

knock to get it moving in the first place. Know what I mean?



Ok. OTHER than that. It's works as advertised. I had a couple a folks joke

about how it was such a waste to use the mount "visually". :) Oh well. If

Roland ever calls me to pay for my 10" Mak-Cass, I'll consider imaging with

the EDT (is there a focal reducer for it?). Until that happens I am looking

forward to using the built-in tours as an observing program.



Clear skies,

Jeff



----------------------------

#2858 Jun 21, 2001

In a message dated 6/21/2001 12:44:05 PM Pacific Daylight Time,

jgortatows@... writes:



> All this to tilt the thing far

> enough to the horizon to get the reticule on a distant marker



It doesn't have to be distant. It can be the eaves of your neighbor's house.



Roland Christen





[Non-text portions of this message have been removed]



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#2859 Jun 21, 2001

In a message dated 6/21/2001 12:44:05 PM Pacific Daylight Time,

jgortatows@... writes:



> . A few

> iterations of the N. Polar Alignment really didn't help. But using the 2

> star alignment did. However a slew to say M15 on the eastern horizon,

> followed by a slew to Mar's on the western side of the meridian, did not

> place Mars in the 1/4 of a degree FOV of a high power eyepiece. But well

> within a 1 degree FOV of a low power ocular.



This tells me that you are off in scope orthogonality by about 1/2 degree.

Therefore, when you switch sides, the scope will be pointing off by twice

that error. The mount is pointing correctly. In order to compensate for this,

when switching sides, point it first to a bright known star, then center and

recal.



Roland Christen





[Non-text portions of this message have been removed]







----------------------------

#2860 Jun 21, 2001

I still found it not easy at all.... Would be great if it was done from

factory.... Just an idea!



At 04:09 PM 6/21/01 -0400, you wrote: >In a message dated 6/21/2001 12:44:05 PM Pacific Daylight Time,

>jgortatows@... writes:

>

>

> > All this to tilt the thing far

> > enough to the horizon to get the reticule on a distant marker

>

>It doesn't have to be distant. It can be the eaves of your neighbor's house.

>

>Roland Christen

>

>

>[Non-text portions of this message have been removed]

>

>

>

>To UNSUBSCRIBE, or for general information on the ap-gto list

>see groups.yahoo.com/group/ap-gto

>

>Your use of Yahoo! Groups is subject to docs.yahoo.com/info/terms/



----------------------------

#2861 Jun 21, 2001

From: chris1011@...> > This tells me that you are off in scope orthogonality by about 1/2 degree.

> Therefore, when you switch sides, the scope will be pointing off by twice

> that error. The mount is pointing correctly. In order to compensate for

this, > when switching sides, point it first to a bright known star, then center

and > recal.

>

> Roland Christen



Hi Roland,



Understood. And if I get lazy and don't want to do proper shimming I'll do

as you say, pointing at a bright star. NBD.



I'll buy a large thin washer or three, or cut some tin or aluminum squares

Saturday morning and bring them with me. Then I'll check the orthogonality

per the manual or your instructions I saved from this group and try a shim

or two. NBD. I just never removed the high power eyepiece so I started

noticing the error.



Now about that 10" Mak-Cass.... :)

Jeff



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#2862 Jun 21, 2001

In a message dated 6/21/01 2:44:39 PM, jgortatows@... writes:

>Setup went very smoothly. I also received a polar scope. What a PITA it's

>reticle was to align! Adjusting it is easy enough. I mean once the dang

>thing is in the RA axis... 'hello!' :) The RA axis is pointed at the sky!

>:)

>Getting some distant telephone pole in the center to align the reticle

>took

>disassembling the altitude adjuster bracket as well as putting two concrete

>block under the SE and SW portable pier legs. All this to tilt the thing

>far

>enough to the horizon to get the reticule on a distant marker. I'm sure

>I am

>stupid and just missed some easier way (in the field?). Okay. All that

>worked once I did the tilt thing.





Jeff:

To "calibrate" the polar alignment reticle I did it in my driveway. I

basically built a simple wedge which allowed me to tilt the mount head so the

polar axis was almost horizontal. I mounted the mount head (1200GTO) on a

piece of 16x16 inch plywood using the regular bolt holes in the baseplate

which I then tilted. The mount head was without counterweight shaft, weights

or rings. This allowed me to completely rotate the polar axis and adjust the

reticle so it's center no longer rotated. For a target, I used the top of a

power pole about 1/2 mile away.

Kent Kirkley



----------------------------

#2863 Jun 21, 2001

Hi Jeffrey, Read your initial report, and viewed the pics of the set-up. Very nice indeed! I gather this "Older" AP EDT is an F-8, Correct?



It looks much larger/longer than the newer 130 EDF's that I've seen. Being that this is no doubt a longer, and heavier OTA, I'm still a bit surprised at the long damping times you have found/quoted.



Perhaps this may be caused by you not attaining better balance of the OTA?

Sounds like you need 2-9lb counterweights for a better match, instead of 1-18lb. I would think damping times should be virtually nil with this combo.



I'm sure as time goes by, you'll become more familiar with the set-up, and things will begin to work out better, and better each time you use it.



BTW, That sure looks like one large DOVELM on top of the 900. Was this one of Greg Mueller's Super Adaptoid DOVELM's? (I have 2 Myself!)



----------------------------

#2864 Jun 21, 2001

----- Original Message -----

From: markdambrosio@...>







> Hi Jeffrey, Read your initial report, and viewed the pics of the set-up.

> Very nice indeed! I gather this "Older" AP EDT is an F-8, Correct?



Hi Mark, Thanks very much. Yes, a 1993 F/8.



> It looks much larger/longer than the newer 130 EDF's that I've seen.

Yup this is the size, tho not the glass, Rich N. has been asking Roland to

build again. :)



> Being that this is no doubt a longer, and heavier OTA, I'm still a bit

> surprised at the long damping times you have found/quoted.



Honest to goodness, so was I. This is at high power mind you. Then I

realized, "What is it we are really testing here?" The ability to touch the

scope, usually to focus, without the image shaking. And I assure you the

image is rock solid. Focusing with an overloaded mount is impossible (or

very hard). It's the hard 'rap' to get it moving that's the culprit here. In

other words the mount is _very_ stable in that it takes a lot to cause the

image to become unsteady. However, once that force is applied, it took a bit

of time to steady it out. And as you say, as I become more savvy with

balancing, I may get better results.





> Perhaps this may be caused by you not attaining better balance of the OTA?

> Sounds like you need 2-9lb counterweights for a better match, instead of

1-

> 18lb. I would think damping times should be virtually nil with this

combo.





Yes. But I guess I and Christine didn't catch that when I was ordering. See,

one 6 and one 9 on the 400 GTO was 'just enough'. So I thought one 18 would

be the ticket. And I hope to put a larger APO on it in a month or so. Or, as

I keep hoping, an AP Mak-Cass.





> I'm sure as time goes by, you'll become more familiar with the set-up,

> and things will begin to work out better, and better each time you use it.



Exactly. We tend to think these things should be easier than an LX200 till

we realize they are not Fork Mounts.





> BTW, That sure looks like one large DOVELM on top of the 900. Was

> this one of Greg Mueller's Super Adaptoid DOVELM's? (I have 2 Myself!)



No sir. That's an AP 15" DOVE15 and 15" sliding bar SB1500. I have a

'normal' DOVELM here as well, and a 17" Losmandy plate on order in

anticipation of hopefully have the larger APO here.



Thanks for the help/comments/advice!

Jeff







----------------------------

#2866 Jun 21, 2001

In a message dated 6/21/2001 3:00:36 PM Pacific Daylight Time,

jgortatows@... writes:



> Now about that 10" Mak-Cass.... :)

> Jeff

>

You mean I never sent you one? Shame on me!



Roland Christen









[Non-text portions of this message have been removed]



----------------------------

#2868 Jun 21, 2001

Jeffrey D. Gortatowsky wrote: > Until I figure out something better, I'll reinforce the pier

> shipping box and use it to carry the pier and legs.



A large Tamrac tripod bag holds the pier just fine; the base legs and the

tension rods fit inside the pier. The base center doesn't fit.



Gus



----------------------------

#2869 Jun 21, 2001

Getting some distant telephone pole in the center to align

> the reticle took disassembling the altitude adjuster bracket

> as well as putting two concrete block under the SE and SW

> portable pier legs. All this to tilt the thing far enough to

> the horizon to get the reticule on a distant marker.



I aligned mine on the peak of the next door neighbor's roof. No contortions

needed. :-)



Gus



----------------------------

#2870 Jun 21, 2001

See, one 6 and one 9 on the 400 GTO was 'just enough'. So I thought one

> 18 would be the ticket. And I hope to put a larger APO on it in a month

> or so. Or, as I keep hoping, an AP Mak-Cass.



I needed two 18's for the Mak-Cass, one 18 and one 9 just weren't enough.



Gus



----------------------------

#2871 Jun 21, 2001

In a message dated 6/21/2001 12:44:05 PM Pacific Daylight Time,

jgortatows@... writes:



> Last weekend I took the 900 GTO out for it's first spin. It's carrying a

> 130EDT vintage 1993. Picture of it and my hand held afocal mars images are

> here:

>



Your images hold promise. I'll send you a composite of some of the frames

averaged in Photoshop.



Roland Christen





[Non-text portions of this message have been removed]



----------------------------

#2875 Jun 22, 2001

----- Original Message -----

From: "Steve Leikind" sleikind@...>

> Jeff,

>

> Those images look very good to me; perhaps even excellent. Some

> stacking and further processing might work wonders with these. What

> kind of afocal setup (camera et al.) did you use?





Thanks for the kind words. I'm going to try again tomorrow night with a

tripod instead of hand holding the Nikon CoolPix 950. IIRC, (poor notes)

most of the images were held above a 4.8 Nagler with a TV 1.8x barlow for

385x at my EDT's 1028mm focal length. Others were just the 4.8 alone. My 4mm

and 2.8mm Tak orthos were impossible to get an image from.



The Fototime site shows a thumbnail. When you click on the thumb you get the

slideshow medium size view. If you click on the image then, you get the

original 2.1mp image. Embedded in that image is the Camera Metadata and most

newer picture viewer can display it. (I use ACDSee.) The exposure and f-stop

details, as well as the time and date, are in the Metadata.



I am going to try my hand at stacking one of these days. But for now,

another member of the group here has offered to 'play' with them and see

what details can be coaxed out of them. I'll post the results when I get

them.



And while I'm at it, I'll try and be more specific and 'careful' tomorrow

night about the settling time (and make doubly sure everything is tight).



Clear skies,

Jeff



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