Posts Made By: Rick Baumhauer

Took delivery of my ETX-125EC UHTC a little over a week ago - after much research, decided it presented the best combination of portability, aperture, and features for me. First night's viewing, hand/eye guiding to Orion Nebula, Jupiter, Pleiades, went well, but the included 26mm Plossl is impossible to use with glasses on (much preferred), and only barely useable with them off - must be replaced!

Thus it begins! First, I have a Celestron Ultima Barlow on the way. Second, acquired a lovely TV 32mm Plossl that I haven't had a chance to use yet, and may end up selling (explained below). Third, picking up a Mead 24.5 SWA, making the TV32 redundant as they have very similar FOV (but will use the TV until the Meade arrives, then compare).

So, what next? Since the ETX-125 is a modest aperture, "slow" scope, FOV is an issue, particularly with Autostar, which I attempted (unsuccessfully) to set up on my second night out. Small FOV and nasty eye relief from the Meade Plossl had me sighting along the barrel with my glasses on to see if the scope was in the neighborhood of the alignment stars, then taking off the glasses and slewing about trying to get the star into view. So, I've decided that I'm only really interested in Wide Field EPs for now, in spite of the cost. (Also, I should note that the short days and lousy weather in New England made the finderscope alignment less-than-good - will be remedied this weekend.)

Continued..........

Pondering getting the 14mm, and somebody brought up the size issue - does anybody have experiencs with the XLs in an ETX scope? How do they fit? I think they should be okay, but wanted to be sure.

Thanks for any info!

Rick Baumhauer
Chicopee, MA, USA

I have an ETX-125, and I'm looking for the best "finder" eyepiece for it - that is, the eyepiece that will give the widest true field.

I currently have a TV 32mm Plossl that I'm pretty happy with, but recent discussions on Usenet have pointed me toward the Celestron Ultima/Parks Gold/Orion Ultrascopic 35mm, which would (theoretically) have a wider FOV. However, I know that actual FOV is dependent on the field stop, and most manufacturers don't actually provide that info.

Along the same lines, I did some checking on the UO 32mm Konig, which (they claim) has a 34mm "clear aperture" and a 52* FOV. Not sure how "clear aperture" relates to field stop, but again, this EP would theoretically give a slightly wider field than the TV. Where can I get a decent price on UO EPs, by the way?

I'm primarily trying to minimize the inherently narrow FOV of the ETX by getting the widest field possible out of my EPs (I have a Pentax 14mm, working on getting a 21mm). Eye relief is also an issue, since I do wear glasses. The TV works pretty well with the eyecup folded down, and I know from comments on Excelsis that the eye relief on the 35mm is perhaps too long for people who don't wear glasses, but seems quite nice for those that do. The UO Konig is supposed to have decent ER as well, from what I've read.

Any info, clarifications, or recommendations gladly accepted - while the TV is nice, I've only really compared it to a Meade 24.5 SWA, which didn't have enough eye relief for me.

Continuing from my question yesterday about widest true field, the answers to which prompted even more questions:

Most importantly, given the the way the calculation for Actual FOV works, I don't understand how "Wide Field" EPs actually give you a wider field. Going by the equation from Televue's website, it's clear that Actual FOV is determined solely by the size of the field stop. How does a Pentax XL/Meade SWA/UWA/Nagler/etc actually give you a wider field than what that equation seems to dictate?

It's my birthday, and I'm thinking about the above item. I'm very happy with the ETX so far (about 4 months on), but would like to get a bit more TFOV for clusters, etc. My current setup includes the UO Konig 32mm, Pentax XL21 and XL14, and the Celestron Ultima Barlow.

My main concern is vignetting, particularly with the low-power EPs (since that's where the wide field would be needed, typically). Somewhat concerned about the extra stuff hanging off the back of the ETX, not for balance reasons (since the scope's nose-heavy), but for reasons of clearance with the base and difficulty viewing near zenith.

Does anybody have any experience with the above setup, or any advice? The cost is fairly reasonable (about $130 with the required visual back), but I don't want to spend the money just to find out that the views are wider, but visually poor.

Long story short - I've owned the above scope (4.5" Newtonian) since about 1985, but it's such a pain to setup and use, I never took it out much. Broke down and bought an ETX-125 setup late last year, and did more observing in the last six months than in the previous 17 years (even with the horrific winter and spring here in New England).

However, I mentioned to my mom that I was going to donate the old scope to a charity, and she decided that she wanted it. She's going to be travelling here from the midwest in about 5 weeks, and will be able to take the scope home with her.

I'd really like to take care of some of the better upgrades for her - upgrade to 1.25", a couple decent Plossls, maybe a reasonable finder - so that she might actually get some use out of it. However, I'm not the most mechanically-inclined guy - I'm capable enough, but I don't have a lot of tools or any place to really work on something over a period of time (live in a 2nd floor apt with 3 cats). Most of the reviews at Excelsis claim that the basic optics of the scope are decent, and while I won't be able to do much for the subpar mount, I'd like to make the scope more useable/pleasureable.

I don't have a lot of money to spend, but I'm willing to invest a bit if necessary. So, where should I start looking for a focuser, finder, etc. that will be as close to a "bolt-on" job as possible?

Thanks for any and all pointers!

Because of the scope's 125mm diameter and 1900mm focal length, I figure that 250-300x is about the useful limit, so don't really need to go lower than 13/14mm (+barlow) to get there. Between the 24.5 SWA and 13/14mm, I have a few choices.

First, I know I can go with the Orion Expanse series for a good price, but after receiving my TV32mm, the Expanse seems decidedly, well, *un-sexy*. Shopped around, read every review I could think of on Excelsis, read this board, and decided that I feel a great deal of flat-out lust for both the Pentax XL series and the Vixen/Orion Lanthanum wide-field EPs.

I'd like to cover the ground below 24.5 down to 13/14 with 2 EPs, and from the reading I've done, it looks like I should try to hit about 16/17mm with one, and 12/13mm with the other. I'd like to pick up one each of the XLs and Lanthanums, primarily to compare them, but the Pentax focal lengths come in a bit high for each of my optimal calculations, with the Lanthanums almost perfect.

Nevertheless, I'm leaning toward the Vixen/Orion 17mm and the Pentax 14mm - I figure I can add a higher power EP down the road if I find these, combined with the 24.5, don't quite cover everything adequately. Have also considered the Meade 14mm UWA, but it's very pricey, and haven't had any luck on the used market so far.

Any and all advice gratefully accepted - I'm really enjoying getting back into astronomy, but I'm discovering that you can easily drive yourself completely insane poring over statistics and reviews trying to make the "best" decision.

Very nice image!

I happened upon the same combination last night with my ETX-125, completely by chance. The weather here had been horrific (either cloudy or bone-chillingly cold) for two months, but it was reasonably clear last night until about 11pm, so decided to break out the scope.

Since I was only able to find a site with a clear view to the west, I couldn't get the scope to align with any of the stars that were visible, so I ended up taking a look at Jupiter manually, tracking with the handbox. When I looked through the finder to get Jupiter centered, I saw a small group of stars very nearby, and spent some time panning back and forth between the two objects, primarily using my 32mm UO Konig.

Mind you, I had no idea what cluster I was looking at, but I looked it up this morning and discovered that it was M44. What a nice way to get back into observing after such a long break.