Dear Weixing
Are you going to try it on a slow scope? I wonder if it will have distortions out to the edge....?
Chris
recommended 2" eyepieces to use with f/15 scope
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chris shaw
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wucheeyiun
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I had my 1RPD on a c102 refractor, its consider a slow scope (F9.8)
Infact, to all slow scope owners with 2" focusing tube, i would recommend to change to 2" eyepiece / barlow / diagonal for it is brighter.
It like making the full use of the small aperture. The image is certainly brighter in my case. however, as of current, the better common 1.25" eyepiece resolve image quality better.
My radian 10mm appears dim compared to my 1rpd, but image wise, radian has a better contrast and spread of colours.
I was able to photograph saturn lately with the scopetronix 2x barlow with 2" enhanced diagonal.
But with the 1.25" ultima barlow, its simply too dim. my 2 cents worth.
Infact, to all slow scope owners with 2" focusing tube, i would recommend to change to 2" eyepiece / barlow / diagonal for it is brighter.
It like making the full use of the small aperture. The image is certainly brighter in my case. however, as of current, the better common 1.25" eyepiece resolve image quality better.
My radian 10mm appears dim compared to my 1rpd, but image wise, radian has a better contrast and spread of colours.
I was able to photograph saturn lately with the scopetronix 2x barlow with 2" enhanced diagonal.
But with the 1.25" ultima barlow, its simply too dim. my 2 cents worth.
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weixing
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Hi,
Remember, as magnification increase, image brightness decrease.
Have a nice day.
Your radian 10mm will give you a lots higher magnification than the 1rpd, so it will be a lot dimerMy radian 10mm appears dim compared to my 1rpd
Remember, as magnification increase, image brightness decrease. Have a nice day.
Yang Weixing
"The universe is composed mainly of hydrogen and ignorance."
"The universe is composed mainly of hydrogen and ignorance." I don't think Sam's closing shop, just thinning his accessories stock..will be a pity if he closes.
I did borrow Sam's 1rpd for my f/12 once. I like the eyepiece, great TFOV, but the internal reflections bothered me. There was a spot of light in the fov all the time. That was enough to put me off. I'm no expert & Kayheem probably has a better assessment of this eyepiece.
I did borrow Sam's 1rpd for my f/12 once. I like the eyepiece, great TFOV, but the internal reflections bothered me. There was a spot of light in the fov all the time. That was enough to put me off. I'm no expert & Kayheem probably has a better assessment of this eyepiece.
Debash
Hi Chris,chris shaw wrote:Sam is still selling? I thought he has closed his business down?
Anyone with experience with a 1 rpd on a slow scope?
Chris
I have used it on my 5" SCT F/10, and it was fine almost to the edge. For the price, I don't think it can be beat.
However, you may have more discerning eyes, so your mileage may vary. Offer is still open for you to test drive my 1rpd on your MCT. Let me know.
Kay Heem
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chris shaw
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Point noted. But for star clusters, resolution and contrast should mean little. So how does the 1 rpd compare with the more expensive wide angle eyepieces on a slow scope for looking at star clusters. I would definitely NOT be using the 1 rpd to look at planets! I'm just concerned with distortions at the edge of field on my f/15 scope.
My f/15 scope is considered a very 'SLOW' scope, am I right??
Also, I looked at the astrobuffet website and they were comparing coatings on the 1rpd and the panoptics. They compared coatings - 1 rpd is greenish while the panoptics are violet/bluish. Why did they do that? Whats the diff between greenish coatings and violet?
Using the 1 rpd, did you notice the internal reflection problems at all??
Chris
My f/15 scope is considered a very 'SLOW' scope, am I right??
Also, I looked at the astrobuffet website and they were comparing coatings on the 1rpd and the panoptics. They compared coatings - 1 rpd is greenish while the panoptics are violet/bluish. Why did they do that? Whats the diff between greenish coatings and violet?
Using the 1 rpd, did you notice the internal reflection problems at all??
Chris
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chris shaw
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- Joined: Mon Oct 06, 2003 5:16 pm
- Location: Newton area
Tried out the UO MK70 32mm konig yet
Pretty fair weekend weather wise. Debash, did you try out the UO 35mm MK70 Konig yet? I am deciding between ordering the UO 35mm MK70 Konig or the 1rpd from Astrobuffet or maybe even the Widescan III eyepiece.
Debash, did you have any problems ordering the UO 35mm Konig from University Optics? How did you do it? Also, why did you prefer the UO Konig over the 1rpd.
Chris
Debash, did you have any problems ordering the UO 35mm Konig from University Optics? How did you do it? Also, why did you prefer the UO Konig over the 1rpd.
Chris
Hi Chris,
Yes I tried the 32 mm UO Konig on Saturday night with Weixing & gang. Note that it is the normal 32 mm 2" Konig (60* AFOV, costs US$ 130+ shipping) and not the 32 mm MK-80 (costs US$ 300+shipping from ITE); MK-70's are in 25 mm & 40 mm version. I bought it from Sam (Harlequin Astronomics).
32 mm, 60* AFOV gives me slightly above 1 degree in my scope. Coating looks good (overall greenish pink). We saw M31, M45, M8, plus others. Looking through it I found the objects quite sharp, it was bright and contrast was good. No internal reflection problem, although it does have blackout problem if the eye was not at the right distance from the eyepiece. I'm waiting for a rubber eyeguard for it, that would make placing the eye much easier without touching the lens (which is huge). It did have distortions (seagulls) right at the edge while viewing M45 - guess I can live with it, especially, except for Nagler all other eyepieces will have this problem. Widescan III has a wider field, but it's much expensive and has pin cushion distortion as well
One point to note: it is impossible to find a used 32 mm 2" Konig on Astromart - people don't seem to sell it once they buy. I had to wait for 2 months to get a new stock from UO. It's always difficult to choose between one eyepiece and the other, except when the price is not the consideration, in which case I would go for Nagler. Not sure if you have seen the review on Cloudynights re. "six low cost 2" eyepieces". Here's the link:
http://www.cloudynights.com/eyepieces/S ... t%202.html
Overall I'm happy with the Konig on first night, will need many more nights to appreciate its worth. You can trust UO quality to be good (made in Japan) at slightly higher cost than 1rpd, but lower AFOV. Widescan III costs much higher (30 mm 2" normal price US$ 245+shipping) for similar performance, at least the FOV is bigger (84*).
Hope this helps. Cheers
Yes I tried the 32 mm UO Konig on Saturday night with Weixing & gang. Note that it is the normal 32 mm 2" Konig (60* AFOV, costs US$ 130+ shipping) and not the 32 mm MK-80 (costs US$ 300+shipping from ITE); MK-70's are in 25 mm & 40 mm version. I bought it from Sam (Harlequin Astronomics).
32 mm, 60* AFOV gives me slightly above 1 degree in my scope. Coating looks good (overall greenish pink). We saw M31, M45, M8, plus others. Looking through it I found the objects quite sharp, it was bright and contrast was good. No internal reflection problem, although it does have blackout problem if the eye was not at the right distance from the eyepiece. I'm waiting for a rubber eyeguard for it, that would make placing the eye much easier without touching the lens (which is huge). It did have distortions (seagulls) right at the edge while viewing M45 - guess I can live with it, especially, except for Nagler all other eyepieces will have this problem. Widescan III has a wider field, but it's much expensive and has pin cushion distortion as well
One point to note: it is impossible to find a used 32 mm 2" Konig on Astromart - people don't seem to sell it once they buy. I had to wait for 2 months to get a new stock from UO. It's always difficult to choose between one eyepiece and the other, except when the price is not the consideration, in which case I would go for Nagler. Not sure if you have seen the review on Cloudynights re. "six low cost 2" eyepieces". Here's the link:
http://www.cloudynights.com/eyepieces/S ... t%202.html
Overall I'm happy with the Konig on first night, will need many more nights to appreciate its worth. You can trust UO quality to be good (made in Japan) at slightly higher cost than 1rpd, but lower AFOV. Widescan III costs much higher (30 mm 2" normal price US$ 245+shipping) for similar performance, at least the FOV is bigger (84*).
Hope this helps. Cheers
Debash