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Cheapest 'ED APO' yet? (Barska Magnus)

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#76 calypsob

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Posted 04 September 2013 - 04:38 AM

No, no agena adapter. I think I am going to drill a hole in the center of my orion adapter and mount it on the focuser with an m4 screw. It looks a million times better now, here is a quick video http://www.youtube.c...h?v=EeWZcUNtmb0

#77 PeterR280

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Posted 04 September 2013 - 08:52 AM

I was going to drill a hole in my generic adapter too but got lazy. Look at the instruction for the finder mount adapter on the Agena web site. It shows what hole to use on the focuser.

The telescope looks great. Congratulations.

#78 calypsob

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Posted 04 September 2013 - 01:53 PM

Thanks it works great. In regards to the gt102 c80 and barska 80 i believe 2 achromats are being compared to a triplet. If this is the case the triplet will always win in color accuracy against any doublet, especially at f7. Each element in the triplrt brings RGB to focus on a separate element while a doublet usually focuses red and attempts to combine green and blue on the second element, the blue that falls out of the spectral capabilities of the second element go out of focus on the image plane thus creating blue chromatic abberations. The c80ed may be a great deal but its expensive for a doublet. The barska magnus 66 ed and 80mm ed are the cheapest apochromatic triplets on the market.

#79 Scottxray

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Posted 05 September 2013 - 12:28 PM

Peter,

I also picked up a Barska 80 and was wondering about the total change in distance of focuser travel after mounting the GSO and C80 adapter?

The original Barska focuser looks to have 3.1 inches of travel ( just like the GSO ) but the adapter rings and two focusers have somewhat different lengths? I would assume
that there is somewhat more IN focus travel, but less out?

I don't want to get in a position of having to use a 2" diagonal with a camera or have the focuser racked nearly all the way out to achieve focus. Have you found any problem achieving proper focus with a camera?

#80 PeterR280

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Posted 05 September 2013 - 06:58 PM

I am not using a camera yet. Only visual so for. I will probably set up a camera at some point.

It looks like you lose about .75 inches on the focuser itself. It is sitting closer to the tube. Travel on the GSO is 2.8 inches.

#81 calypsob

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Posted 05 September 2013 - 07:24 PM

Scott, I will let you know if the camera has issues. It should not have issues however because with the magnus focuser I could focus on stars when the tube was about 2.5" out of the focuser, the GSO goes out at least 5" so there should be plenty of room.

#82 PeterR280

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Posted 05 September 2013 - 09:53 PM

i'm using a 1" extension for my Nikon. it gives plenty of room without diagonal.

#83 calypsob

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Posted 07 September 2013 - 05:00 AM

Scott, The barska will bring stars to focus at the 6 cm mark on the focuser scale when in use with the 80mm magnus, I confirmed this tonight with my t2i.

#84 Scottxray

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Posted 12 September 2013 - 08:29 PM

Thanks. After a careful cleaning of the Barska focuser it is working well for astrophotos. It is holding focus perfectly, even at straight up views. Although it feels a little rough it is perfectly functional, especially since photos are set with a Bahtinov mask. I have not had any focus changes on any of many sets I've taken, even over hours.

What I DO need is a good field flattener, slight reducer.
My outer edge stars are showing nice little oblong donuts at all four corners, (just as they should without correction). I tried a meade F6.3 but it overcorrects the flat field and I get ovals that are at 90 degrees to the donuts angles ( when no flattener is used) at the field edges. It also vignettes too much.

Anyone know of a great flattener for the Barska?

#85 jag767

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Posted 13 September 2013 - 03:39 PM

Maybe I missed it, but did anyone try the 65mm Version of this scope?

#86 PeterR280

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Posted 14 September 2013 - 08:12 AM

I just got the first look at Jupiter this morning with the 80mm Barska. Highest magnification was with a 4.7mm ES. I have to say seeing is amazing that early in the morning. The atmosphere is very calm. You could see the banding quite sharply. The telescope shows no color fringing on Jupiter.

#87 calypsob

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Posted 10 October 2013 - 01:35 PM

Thanks. After a careful cleaning of the Barska focuser it is working well for astrophotos. It is holding focus perfectly, even at straight up views. Although it feels a little rough it is perfectly functional, especially since photos are set with a Bahtinov mask. I have not had any focus changes on any of many sets I've taken, even over hours.

What I DO need is a good field flattener, slight reducer.
My outer edge stars are showing nice little oblong donuts at all four corners, (just as they should without correction). I tried a meade F6.3 but it overcorrects the flat field and I get ovals that are at 90 degrees to the donuts angles ( when no flattener is used) at the field edges. It also vignettes too much.

Anyone know of a great flattener for the Barska?


Hey sorry I missed this, the Hotech SCA field flattener works great for the magnus, you just need to get one that is designed for an F7, the Hotech fits the bill. Also, how did you get the barska focuser to work so well? I could back the image into focus but I was never able to get it to pull the weight of the camera back into the tube. It really is a nice focuser build wise, internally baffled and very tight tolerances which prevent any shift from locking it up whatsoever, but I hated that I could not get it to focus smoothly. I get a little bit of shift with the new GSO focuser but it is silky smooth.

#88 calypsob

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Posted 10 October 2013 - 01:38 PM

Maybe I missed it, but did anyone try the 65mm Version of this scope?


No but I have been curious about it. The AT65 ed would be its biggest competitor, and for a $150 field flattener I would probably roll with the At65 instead

#89 calypsob

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Posted 10 October 2013 - 01:42 PM

Oh and here is a short video of the GSO focuser on the magnus http://www.youtube.c...h?v=EeWZcUNtmb0

#90 calypsob

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Posted 10 October 2013 - 01:47 PM

As for chromatic abberations, My astrophotography skills are not that great, and my mount does not guide perfect, but the scope delivers fringe free images Posted Image
veil 2 by LMNO Sunset Deluxe, on Flickr

#91 jag767

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Posted 10 October 2013 - 01:52 PM

Maybe I missed it, but did anyone try the 65mm Version of this scope?


No but I have been curious about it. The AT65 ed would be its biggest competitor, and for a $150 field flattener I would probably roll with the At65 instead


best buy has it for 349, and I have a friend who works there can probably get at least $50 off of that. So for 299 I'm thinking super finder/travel scope?

#92 PeterR280

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Posted 10 October 2013 - 02:07 PM

Great photo Calypsob

#93 calypsob

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Posted 10 October 2013 - 09:13 PM

Maybe I missed it, but did anyone try the 65mm Version of this scope?


No but I have been curious about it. The AT65 ed would be its biggest competitor, and for a $150 field flattener I would probably roll with the At65 instead


best buy has it for 349, and I have a friend who works there can probably get at least $50 off of that. So for 299 I'm thinking super finder/travel scope?


Yea it would be crazy to pass up.

#94 calypsob

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Posted 10 October 2013 - 09:14 PM

Great photo Calypsob


Thanks man, more to come if skies permit.

#95 jag767

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Posted 11 October 2013 - 08:07 AM

Maybe I missed it, but did anyone try the 65mm Version of this scope?


No but I have been curious about it. The AT65 ed would be its biggest competitor, and for a $150 field flattener I would probably roll with the At65 instead


best buy has it for 349, and I have a friend who works there can probably get at least $50 off of that. So for 299 I'm thinking super finder/travel scope?


Yea it would be crazy to pass up.


You guys are a bad influence! Got the 65mm for 296 no tax free shipping with 2 eps, diagonal, and case.

#96 PeterR280

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Posted 11 October 2013 - 12:32 PM

I got my Barska 80mm for $349. earlier this year. There was a few weeks where Amazon dropped the price, then they increased it.

#97 jag767

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Posted 12 October 2013 - 06:18 AM

Alright 65mm is on its way. Only problem I potentially see is if I decide it's a keeper but hate the focuser what I can do in terms of replacing it. I have a feeling my only option will be a custom flange from moonlite, and oh yea, doubling my cost by having to buy a moonlite :bawling:

I didnt realize how butt ugly the finish on these are until it already shipped, so if the lens fit what I want for a super finder and travel scope, its getting fully dismantled and redone. Perhaps a pearl cream or metallic blue.

#98 PeterR280

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Posted 12 October 2013 - 08:09 AM

I put the GSO focuser on my 80mm.

#99 jag767

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Posted 12 October 2013 - 08:15 AM

I put the GSO focuser on my 80mm.



I had hopes to do the same, but I'm thinking there's a good chance there's no flange small enough....

#100 calypsob

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Posted 17 October 2013 - 01:57 PM

GSO makes an 86mm flange, you will have to measure it when it arrives. Moonlight will make you a custom adapter, as would most any machine shop. It is just going to be a threaded step up adapter, one side threade, the otherside would be a male flange fitting for the female flange coupling on the GSO, or whatever you decide to go with.






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