I strolled into York Optical (Brisbane) at about 5 minutes to closing yesterday arvo. Went looking for a Barlow and higher powered EP (7-5mm range).
Walked out with 1 Barlow (Optex 2X fully multi-coated) sold at $87 buckaroonies AND an EP ({Tasco}York ED 7.5 fully multi coated) sold at $45 buckaroonies. A $22 discount (VIP card) on combined sale.
Took em out for a test run last night and Saturn was the target. The 7.5 has beautifull eye-relief, is nice and large/heavy, and gives crystal images.
The Barlow is light but the lense is fairly heavy and with my 10mm and 7.5mm gives a close up view of Saturn.
The Barlow does return a larger image but is blurry, dark and no finer detail except fleetingly when the image is sharp (atmospheric abberation probably).The image is a little murky and I understand the filter loss. Is this down to the aberration or possibly poor quality lense? I'm only new to the game so cant really give you technical aspects such as coma and FOV although coma does seem to be slightly evident but not enough to write home about and FOV seems redundant at this kind of Mag.
I've got 1 business week to make up my mind about said EP's. Can any one offer advice etc? "Mental" helped me out with a few choices on the forum thru the week but It was a spur of the moment decision to spend some dollars with York Optical and this "starter set" was value for money . I guess under dark skies these materials would work better away from a city atmosphere.
:ques tion:
Any comments are warmly welcomed,
Cheers, and over to you
John
Last edited by The3rdKind; 17-04-2010 at 03:39 PM.
Reason: add photos
John,
Assuming good collimation, coma is less of an issue at higher power and smaller fields of view.
With 1200mm aperture focal length, the 10mm EP gives a magnification of 120 and the 7.5mm EP a magnification of 160.
With the 2x barlow, the magnifications will bump up to 240 and 320. The 240 will require rather good seeing conditions but the 320 will require excellent seeing, which is rather a rarity. If the image is jittery, sometimes in focus but more often not, then seeing is poor.
The barlow is useful but you will need good seeing conditions.
John,
Assuming good collimation, coma is less of an issue at higher power and smaller fields of view.
With 1200mm aperture focal length, the 10mm EP gives a magnification of 120 and the 7.5mm EP a magnification of 160.
With the 2x barlow, the magnifications will bump up to 240 and 320. The 240 will require rather good seeing conditions but the 320 will require excellent seeing, which is rather a rarity. If the image is jittery, sometimes in focus but more often not, then seeing is poor.
The barlow is useful but you will need good seeing conditions.
Regards, Rob.
Thanks Rob,
I think I need more experience etc but wanted to try out some reasonably cheap versions of EP to give me a feel. I am, overall, really happy with my purchase and from here I can hone in on what "mental" suggested as good EP's without substantial outlay of buckaroonies! Also I not one for picking on other observers at viewing nights and asking for a lone of their equipment.
I don't really know what coma is so I was guessing . Thanks for your comments .
me, if it had Tasco on it and it wasnt made in the early 1960's id keep walking..... and save up for something better.
Gidday torana68,
It didn't have tasco written on their but it had York (as in York Optical line). But going off the docket where it did have tasco written there somewhere I assumed it was. Yeah, I know what you mean bout tasco. I've got a pair of tasco 10x50 binos (chrissy present from my beaut mum in '85). Very good. However the image is bright and clear in this EP. But I think I'll get a 6mm or 5mm sooner rather than later. Its just a ? of buckaroonies.
yeah i dunno just me maybe but some brand names make me nervous, Telstra is another , Id always steer clear of house brand stuff, I prefer the original if its something I want, with the original name on it , does that make me a "brand *****"?
yeah i dunno just me maybe but some brand names make me nervous, Telstra is another ,
Don't start me on Telstra mate. Anywayz TPG is a reasonably safe bet.
I only found out about the whole Tasco swindle after I walked to my car looking at my mint condition docket
But to repeat, it is an OK EP (at least on a par with my 10 & 25 Plossls lumped in when I bought my tube).
Its just that the optex barlow at 320x (with the 7.5mm) does get a little smokey moreso than blurry. I know Sirius optics here in Brissy have them at a similar price. I thought I would get better contrast to make out some planetary detail (ie Saturn's Gassy rings on the planet itself). The 7.5 appears to have a good lens rubber bit (the part yu rest yr eye on) but sadly a bit short on eye relief (downright annoying).
I'm just worried that if I make up my mind to scream refund I might have blown what could arguably be a bargain under really good night viewing circumstances (ie dark sky, winter, after a fresh cold front)
Anyways, not taking them back just yet and my club meeting is on Tuesday night so I'll take them along there to probably add to my confusion. I dunno, it just instinctively felt like a bargain
Anyways, not taking them back just yet and my club meeting is on Tuesday night so I'll take them along there to probably add to my confusion. I dunno, it just instinctively felt like a bargain
Cheers anyway torana,
John
right so was it like the first V8 you drove or more like the feeling French car owners get when the reality of their choice hits home (and they have to spend years extolling the virtues of French engineering to keep face )
Roger
right so was it like the first V8 you drove or more like the feeling French car owners get when the reality of their choice hits home (and they have to spend years extolling the virtues of French engineering to keep face )
Roger
Yeah Roger probably! although I'd like to add laziness uncertainty fear and loathing
The first V8 I drove I nearly wrapped round a tree. My uncle owned a 2nd hand Renault that always seemed to be at the servo's mechanic shop.
Perchance I happened to Barlow down my 7.5 for a moon gawk and it was crystal
The eyepiece and barlow you bought are fine. Remember in a PM I sent you that being able to use anything over 300X for a really good image is very, very rare. What you were seeing through the EP and barlow was the aberration due to atmospheric conditions. It is what Rob described as 'poor seeing'. Winter, as a general rule, gives better seeing conditions than the warmer months as the cooler atmosphere is less turbulant.
You will find that you'll get most practical use out of using the 7.5mm neat. 160X is about as high as the atmosphere normally allows. Your description in the first post pointed that out. As you bumped up the power, you lost image quality, not due to the barlow though.
There is nothing, nothing wrong with the "York" or "Tasco" EP you got. Actually, it is a very good buy. I had also mentioned in a PM that cheap high power EPs are poor. There is a limit to what an inexpensive optical design and inexpensive lens materials will do. The option you've choosen is a very good compromise: a better optical design coupled with improved lens materials to give you a really comfortable, AND practical eyepiece. That is what you want.
If you want to raid the piggy bank, well, go for it. Throwing money at something can help overcome certain obstacles, but not ego for some. I'm an advocate for more clever amateur astronomy, taking into account money, materials, optical principles and human eye physiology. I'm quite happy with a 4 cylinder boxer engine.
Also a little bit of research will help out alot too, as many products are made by the same firm, just rebadged. This will spell out big savings too. When you find out that SkyWatcher, Tasco, Celestron, Synta, and a few others, are really all the ONE company, makes you wonder what you are really getting. And then they also rebadge their stuff for generic brands. See what I mean. This is by no means limited to them, I'm just using this as an example. It is a means for making money. Nothing more. Buyer beware for real value.
The eyepiece and barlow you bought are fine. Remember in a PM I sent you that being able to use anything over 300X for a really good image is very, very rare. What you were seeing through the EP and barlow was the aberration due to atmospheric conditions. It is what Rob described as 'poor seeing'. Winter, as a general rule, gives better seeing conditions than the warmer months as the cooler atmosphere is less turbulant.
You will find that you'll get most practical use out of using the 7.5mm neat. 160X is about as high as the atmosphere normally allows. Your description in the first post pointed that out. As you bumped up the power, you lost image quality, not due to the barlow though.
There is nothing, nothing wrong with the "York" or "Tasco" EP you got. Actually, it is a very good buy. I had also mentioned in a PM that cheap high power EPs are poor. There is a limit to what an inexpensive optical design and inexpensive lens materials will do. The option you've choosen is a very good compromise: a better optical design coupled with improved lens materials to give you a really comfortable, AND practical eyepiece. That is what you want.
If you want to raid the piggy bank, well, go for it. Throwing money at something can help overcome certain obstacles, but not ego for some. I'm an advocate for more clever amateur astronomy, taking into account money, materials, optical principles and human eye physiology. I'm quite happy with a 4 cylinder boxer engine.
Also a little bit of research will help out alot too, as many products are made by the same firm, just rebadged. This will spell out big savings too. When you find out that SkyWatcher, Tasco, Celestron, Synta, and a few others, are really all the ONE company, makes you wonder what you are really getting. And then they also rebadge their stuff for generic brands. See what I mean. This is by no means limited to them, I'm just using this as an example. It is a means for making money. Nothing more. Buyer beware for real value.
Mental.
Thanks Alex,
Yes I do remember your post as I have kept it and am using it as the foundation of my research for EP's. The EP's I bought were spur of the moment but it felt right. I needed some EP's rather quickly. The guy at York Optical here in Brisbane is in my club and he is genuinely interested in customer satisfaction and knows a little about how an amatuers natural EP evolution is going to occur, in general.
Your comments about abberation are exactly what I have experienced and to which yourself and Rob pointed out respectfully. Roger, can you tell me more about your EP's as I think your a bloke who is mindful of ego and value for money as well. Don't know if you guys are ever up this way but would like to have a viewing night with you sometime, if you don't mind me asking 20,000,000 questions??
20,000,000 questions? I think I only have 2 or 3 answers and one of those is "yes dear" so Im probably little help. All id say is choosing by brand name and cost wont give the best choice, its your eye, type and focal length of scope, quality of the telescope (no point putting a $400 eyepiece on a $40 telescope) and what you want to do with all the above. Im into planets with reflectors so its University Optics for me. The difference between these and the widetelepansnobview ones isnt worth the extra money to me, I got bills to pay
[QUOTE=torana68;587791]20,000,000 questions? I think I only have 2 or 3 answers and one of those is "yes dear" so Im probably little help /QUOTE]
No worries! Got the same yes dear thing down myself. I love how they start throwing questions at you during footy and then complain when you don't give in depth answers
Please critique my new EP's
. I guess under dark skies these materials would work better away from a city atmosphere.
. Thanks for your comments 
