Author Topic: Short FL eyepieces - advice  (Read 364 times)

arovuzar

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Re: Short FL eyepieces - advice
« Reply #15 on: January 26, 2018, 04:04:04 AM »
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I borrowed a 5mm AT paradigm eyepiece and tested in my AT115. Optically, I was pleased for the most part... when I could get it focused - lol. The big problem was my mount - I will post a new thread in the mounts forum. My TWII mount just could not seem to handle the AT115 at powers over 100. Well maybe... but I didn't have a 6mm to test only an 8mm and 5mm. Settle times are unacceptable and focusing is a nightmare. Not sure what the problem was but it was NOT acceptable.  We even barlowed the 5mm to 2.5mm and it was impossible to focus due to shakes. The 5/2x combo worked perfect on ED80 with AVX mount. Settle times 4-5 seconds on TWII and less than a second on AVX/ED80. So I won't be buying anything until I get my mount issues sorted out.

A few thoughts... Jupiter moved by quick even with 60 AFOV - I did look at M40 I think the cluster in Canus Major - whatever one it is - it was nice even with the moon out and we were in some light pollution too in the city. So I can see where the darn 4.7 Ethos would be great in the AT115 - HAVASMAN. I have not looked through a Nagler T6 only the T4s. How is the eye relief in 5T6 compared to ES4.7 ? - I had the ES4.7 and 6.7 and they were tight and uncomfortable for me. I sold them. The 15mm eye relief on Ethos feels like it was made for me. I would definitely consider 5T6 and 3.5 combo if they were a bit easier to look through then the ES. If not it's Pentax XWs or more Ethos for me.

But I won't be getting crap until I figure out why my mount sucked tonight. I have never went above 100 power (8E) in the AT115 before until tonight. Really bummed about it. I even put my ED80 on the other side to balance it out and it still had the shakes. Mount is fine at 100 x and below.

oh well thanks everyone for the comments and replies

k

I was there for the AT Paradigm test in three different scopes. My 114 Reflector, Kris ED80 on my AVX Mount and Kris's AT115 on his TWII mount. The views were the best in the AT115 the 114 Reflector and the ED 80 were comparable. The focus times on the ED 80 with the 5mm were one second or less and no problem. The Reflector on the GT Mount with 8 to 10 seconds of settle time were really difficult and the TWII was probably 4 or 5 seconds. The AT Focuser works great but as Kris says the TWII had problems with the AT, at high power. At lower magnifications the AT was not problem. Once we did get the telescopes focused the views were rather good. Jupiter in the ED80 at 240X was surprisingly good at 10pm. The Paradigm 5mm really is worth the $60 it sells for new. 13mm eye relief was not bad either. I am also going to help Kris to figure out the TWII issue at high power. for anything 8mm and lower it did work very well.

David

Mario Carpenter

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Re: Short FL eyepieces - advice
« Reply #16 on: January 26, 2018, 07:34:23 AM »
I hate to say it, but when it comes to mounts...ES...half the mount at full price. I've also met a couple of folks who had problems with theT2 az motion becoming sluggish in one or two areas as they moved the scope. The T1 should be listed as 10lb max load, not 18.

Seth Mamidi

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Re: Short FL eyepieces - advice
« Reply #17 on: January 30, 2018, 04:45:43 AM »
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So I won't be buying anything until I get my mount issues sorted out.

k


Anthony Graham

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Re: Short FL eyepieces - advice
« Reply #18 on: January 30, 2018, 04:58:21 AM »
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I hate to say it, but when it comes to mounts...ES...half the mount at full price.  I've also met a couple of folks who had problems with theT2 az motion becoming sluggish in one or two areas as they moved the scope.  The T1 should be listed as 10lb max load, not 18.

I posted a thread in the mounts forum for help but going to consider a new mount.  Maybe an M2 or AZ8.  I don't really need a dual saddle mount though.  The M2 would be perfect but it looks like it uses the same tripod as my TWII.  I'm pretty lost as far as mounts go... the UA unistar business I read is being shut down no more made and I don't want to wait 3 months for a Dsv3.
I know this scope is solid on an AVX but even if I went that route I would still want a manual altaz at some point.  Really stinks but at least I not shell out $$$ on eyepieces only to find out later about mount.

Maurice Deuschle

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Re: Short FL eyepieces - advice
« Reply #19 on: January 31, 2018, 04:16:42 AM »
Friend of mine's got his SW 102 refractor on an M2 - very nice and steady. He has the post/extender between the mount & tripod. I didn't really expect it to be as solid as it is but I'd never seen one. It holds his scope as well as my UniStar Deluxe holds mine. His scope may be a bit lighter but it's longer and presents a very similar load.

ovhercayvic

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Re: Short FL eyepieces - advice
« Reply #20 on: January 31, 2018, 05:38:52 AM »
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Friend of mine's got his SW 102 refractor on an M2 - very nice and steady. He has the post/extender between the mount & tripod. I didn't really expect it to be as solid as it is but I'd never seen one. It holds his scope as well as my UniStar Deluxe holds mine. His scope may be a bit lighter but it's longer and presents a very similar load.ever g

If you wouldn't mind maybe you could try your AT115 on friends M2 for me?? I am going to play around with some recommendations I got for TWII but NOT going to go crazy dumping much $$$ in to the TWII.  I have been eyeballing the AZ8 since they forever. Their is another thread where someone purchased one and also has a TWII and there are pictures. The TWII looks so much more beefier then the AZ8 but the Losmandy has to be better given reputation.

I mean there is nothing mechanically wrong with my TWII, I think it's just putting that AT115 on one side without counter balance - it's just too big a scope to use on those dual clamp mount without another scope. I don't really need the dual clamps as it's impractical to have 2 scopes pointed in the same spot anyway. Last star party at my farm house someone borrowed my TWII and had 2 100mm refractors on it and it was solid - they were both 900mm with a 5mm eyepiece too so even higher magnification then what I was using. However, I bet my AT115 weighs as much or more than the 2 ED100s on 1 clutch where as he had the weight distributed evenly. Oh well... I figure something out. Need to play with it a bit more too.

noerivatat

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Re: Short FL eyepieces - advice
« Reply #21 on: January 31, 2018, 05:49:52 AM »
I can't know when that might be likely to happen but if the opportunity arises then we'll take a shot at it and I'll let you know how it comes out. But I don't recommend you wait to hear from that chance.

safrioheartli

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Re: Short FL eyepieces - advice
« Reply #22 on: January 31, 2018, 07:02:54 AM »
There are many good alt-az mounts. None of them is really light in weight.
A good rule of thumb is to cut every "manufacturer's quoted weight carrying limit" by 50% to yield a stable mount for high powered observing.
That weight limit will include your OTA with all accessories including rings.
Knowing what load you'll put on the mount will help.

Tim Jauregui

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Re: Short FL eyepieces - advice
« Reply #23 on: February 08, 2018, 06:31:28 PM »
My advice--consider a 2.5X Powermate. Your 13mm and 8mm Ethoi would become effectively become a 5.2mm (155X) Ethos and a 3.2mm Ethos (252X). The Celestron Luminos 2.5X Barlow is another barlow to consider if you're worried about a giant Ethos eyepiece sticking out of a Powermate with a 1.25"-barrel.
Another possibility is get a 2X and 4X Powermate (both 2") and you'll have 100° focal lengths at 21mm, 13mm, 10.5mm (not sure you REALLY want to barlow a 21mm Ethos...but you COULD), 8mm, 6.5mm, 5.25mm (21E + 4X-PM) 4mm, 3.25mm and 2.0mm.
And yet another possibility is get a 2.5X Powermate and a Baader Zoom. The 24mm setting would probably have too small a field of view for your tastes, but it's about 60-70° at the 12mm and 8mm settings (effectively 4.8mm to 3.2mm w/2.5X Powermate). The advantage here is that you could fine-tune between the click-stops to get the optimal magnification.
Just my 1.4-cents' worth. It was worth 2 cents, but that was before taxes.

Clear Skies,
Phil

nalchsilnighnul

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Re: Short FL eyepieces - advice
« Reply #24 on: February 08, 2018, 07:08:01 PM »
I've read the Tw ll mount works smoother when counterbalanced especially
with a heavier scope on one end. Maybe experiment by hanging some weight
off it.