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Hole Inside Eyepiece Holder of Mark V

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#1 Kent10

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Posted 06 April 2013 - 05:01 PM

Hi:

I have been using my Mark V Binoviewer with my Lunt solar scope. I noticed a glint when using my Leica ASPH Zooms. It is in the right eyepiece only. I looked inside the eyepiece holder with the eyepiece removed and there is a hole on the upper left. This is letting in light. The 1.25" adapter to my Leica is very short and so light is getting inside the lens and reflecting. I'm not sure why that hole is there and I am wondering if someone else could check to see if you have a hole inside the eyepiece holder on the right side only. There is no hole on the left side. Thanks! Kent

#2 Kent10

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Posted 06 April 2013 - 05:09 PM

Here is a pic I found. I guess the hole should be there but you lose contrast with light getting in if the eyepiece doesn't extend past that hole.

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#3 Kent10

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Posted 06 April 2013 - 05:31 PM

I may have to get the Starlight 2" adapter and then this 1.25" to add on. I will have to be sure it is long enough so light doesn't come inside.

http://www.adorama.c...CFW7hQgodOx8AWA

http://starlightinst.../product&pro...

#4 Mark9473

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Posted 06 April 2013 - 05:41 PM

Why don't you just add on a 1.25" extension? Something like this.

#5 Kent10

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Posted 06 April 2013 - 05:49 PM

Thanks Mark. That may work. The Leicas already need a lot of in focus though so if I push them out more I wonder if I will be able to focus. The one you linked might be a little long so I will have to check but if I can buy these instead of the adapters that will be a lot less. Thanks very much.

I also am thinking about stuffing something in the hole. I have a Baader Vip Modular Barlow and it has the 1.25" adapter that I linked to above. It is long enough but since I can see through the top easily, I can see light still gets in. It is less light but I wonder if this will solve the problem.

#6 Mark9473

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Posted 06 April 2013 - 05:59 PM

An alternative is that you ask APM to make you a set of slightly longer 1.25" adapters to replace the ones you now have on your eyepieces.

#7 Kent10

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Posted 06 April 2013 - 06:07 PM

Thanks again Mark. I just measured and the APM 1.25 extension on the Leica is almost 18mm so adding the 2nd 18mm extension would make it a few mm too long. Still it might work. And also asking APM to make new ones would work too. Thanks for the suggestion. I know they will custom build those adapters. Actually I would need just one longer one for the right side :) Maybe APM can make an add on piece shorter than 18mm. I will also keep searching to see if I can find one a little shorter than 18mm and if I could purchase it in the US that would be convenient too.

#8 Kent10

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Posted 06 April 2013 - 07:57 PM

With the help of Rex I found a 1.25 extension at Scopestuff. I measured and it will probably be only about 1mm too long and that should work so I ordered it.

#9 DaveJ

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Posted 07 April 2013 - 07:23 AM

With the help of Rex I found a 1.25 extension at Scopestuff. I measured and it will probably be only about 1mm too long and that should work so I ordered it.


Hi Kent,

I looked at what was available at Scopestuff. I decided to check AgenaAstro as well and found 1.25" extensions in these lengths: 1", .75", .5" and .25" and all are in stock. Page showing all of them is here.

#10 Kent10

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Posted 07 April 2013 - 09:07 AM

Thanks very much Dave. Good to know. I can't wait to try the extensions out and I hope it eliminates the terrible glare. It is extreme.

BTW did you ever get your 2.6 GPC to work in the proper orientation in your Herschel Wedge? You may recall this thread.

http://www.cloudynig...5230304/Main...

Thanks again.

#11 DaveJ

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Posted 07 April 2013 - 11:52 AM

BTW did you ever get your 2.6 GPC to work in the proper orientation in your Herschel Wedge? You may recall http://www.cloudynig...5230304/Main....


Hi Kent,

Yes, I did get it figured out, but wasn't totally happy with the whole way of doing it. Let me explain... As we all know, the 2.6GPC must not be screwed into the MarkV as the 1.25 & 1.7 GPCs are, but, rather, turned around and screwed into the top of the diagonal followed by the quick-change adapter. This won't work for the Herschel Wedge since it doesn't have sufficient clearance due to the position of the ND3 & Solar Continuum filter. I continue to consider disassembling the 2.6 GPC and reversing the lenses so that it would have the same orientation as the 1.25 & 1.7 GPCs as was shown in this thread. Here's why I haven't done this yet - it seems like such a simple thing to do, so why didn't Roland Christen design it that way? One has to wonder. Perhaps the spacing of the lens elements require it to be that increased distance from the prisms. Who knows!? I plan to ask when I see him at NEAF in two weeks. So, where was I? Oh yeah. Trying to fit the 2.6 GPC in the correct/approved orientation with the MarkV & Herschel Wedge given the space restrictions. I called George at Astro-Physics and he said to acquire this SCT Gender Changer from AgenaAstro. Using that new part plus the original SCT male threaded adapter that came with the Herschel Wedge winds up giving the additional 7mm space required to keep the 2.6GPC from hitting the filters. You then need to screw on this part (which I already had), drop the 2.6GPC nose-down into this part and screw on the quick-change female adapter. I discovered right away that you had to place a tight-fitting spacer that comes with the GPCs to use when placing the GPCs in the nose of the diagonal. As you'll recall, the GPCs don't screw into the nose, but rather are placed into the diagonal and held in place by the nose - but require the spacer to keep the GPC centered in the front of the diagonal. Why am I not totally happy with this arrangement? I would much prefer that Baader had provided a screw-in arrangement so that the 2.6GPC could be securely attached without messing with that plastic/fiber spacer to keep it centered. Yeah, I know - I'm picky - but this arrangement just seems a little Micky Mouse given the high quality and versatility of the rest of the gear. OK, let the questions begin... :imawake:

#12 Kent10

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Posted 07 April 2013 - 12:08 PM

Thanks for explaining this, Dave. At least you got it working. The other alternative would be to use shorter focal length EPs in the bino with the 1.7 GPC which also is not recommended but some do it successfully I have heard. I have the same problem with installing the 2.6 GPC in my Lunt LS100 solar refractor. You can't put it in the Lunt diagonal so I have been using it positioned in the same way as the 1.7. I haven't done a critical analysis and I am not that experienced but it worked for high magnification views of prominences. You mention the thread with the disassembled 2.6. Coincidence that I just bought that reversed 2.6 GPC from George. Just this morning! So I wonder the same thing about why they made it that way and if it will be as good but I am going to try it and compare with the one I have. Maybe they made it for the Maxbright. Don't the GPCs work differently in those binos. Not sure. I seem to remember reading that they do and I also thought I remember reading that Baader was considering making a different version of the 2.6. I am not sure in what way. Anyway, all very interesting. Thanks for your explanation.

#13 DaveJ

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Posted 07 April 2013 - 12:42 PM

Thanks for explaining this, Dave. At least you got it working. The other alternative would be to use shorter focal length EPs in the bino with the 1.7 GPC which also is not recommended but some do it successfully I have heard. I have the same problem with installing the 2.6 GPC in my Lunt LS100 solar refractor. You can't put it in the Lunt diagonal so I have been using it positioned in the same way as the 1.7. I haven't done a critical analysis and I am not that experienced but it worked for high magnification views of prominences. You mention the thread with the disassembled 2.6. Coincidence that I just bought that reversed 2.6 GPC from George. Just this morning! So I wonder the same thing about why they made it that way and if it will be as good but I am going to try it and compare with the one I have. Maybe they made it for the Maxbright. Don't the GPCs work differently in those binos. Not sure. I seem to remember reading that they do and I also thought I remember reading that Baader was considering making a different version of the 2.6. I am not sure in what way. Anyway, all very interesting. Thanks for your explanation.


The GPCs in the Maxbright binoviewers ALL fit the wrong way for us with the MarkVs (see ad here). Apparently, the 1.25 & 1.7 GPCs are assembled with a reversed-lens arrangement for the Maxbrights compared to those for use with our MarkVs. If that's the case, then why, oh why, is the 2.6 assembled the way it is? I really want this question answered!! Is it something that Baader does just to be ornery? or is there a spacing issue as I mentioned before? I sure hope to find out from Roland in 13 days. Congrats on getting that 2.6 from George. I was thinking of contacting him to see if he'd perform the reversal service for me. I'm anxious to hear your opinion of the views. The reason I was so anxious to get the 2.6 GPC to work with the Herschel Wedge was because I often grab an 80mm Apo for a quick solar fix. This scope won't reach focus with the Herschel + MkVs without the 2.6 GPC. The 102mm and 140mm Apos I use normally can be used with no GPC at all, or any of the three, so that's not normally a problem - only with the 80mm for quick views.

#14 Moonglum

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Posted 07 April 2013 - 01:34 PM

The threaded spacers do not solve the problem entirely, although they will reduce the glare, they will not eliminate it. All of my planetary pairs of eyepieces do not reach the bottom of the holders just as you describe, and I too see the glare on the right side during the day. All of my pairs that is, except my RGO 7mm's. These orthos have extra long barrels and "bottom out" in my Mark V's. There is less glare with this pair, but I see no glare on any eyepiece in the right side at night. I believe it to be ambient light reflecting off the white paint on the Mark V's. The problem is the "hole" as your picture shows, actually wraps around the corner of the eyepiece holder. Now that I think about it, perhaps a black rubber o-ring inserted just inside the end of the eyepiece barrel would help...

#15 Kent10

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Posted 07 April 2013 - 01:39 PM

Thanks Moon. You are right. I used a barlow that did go all the way to the bottom and you could still see a small amount of white light. But I am hoping it will greatly improve what I was seeing which made the Leica EP unusable. It did change as I zoomed so I think it depends where the glass is. I was also thinking about blacking that part out on the paint or inserting some sort of dark material in there but I haven't given it too much thought. I will try the extender first and see how that works.

#16 Kent10

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Posted 07 April 2013 - 03:24 PM

I sure hope to find out from Roland in 13 days.


That will be very interesting. I hope he has an explanation.

#17 Moonglum

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Posted 09 April 2013 - 06:32 PM

Well a black rubber O-ring didn't help at all. I'm surprised this issue hasn't been discussed til now. This seriously hampers the Mark V's value for daytime use.

#18 Kent10

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Posted 09 April 2013 - 06:49 PM

Thanks Moon for the update. I know. I was really surprised when I found the hole. I wonder if something can be stuffed in there or if painting it black would help. Stuffing something might be difficult because then changing the distance between sides might not work so well.

#19 Kent10

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Posted 10 April 2013 - 04:51 PM

I received my extensions today and only had a short viewing session of the sun but I think the extensions solved the problem. It is a lot better and usable now. When I have more time I will check things out a little closer. Thanks everyone!

#20 Moonglum

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Posted 10 April 2013 - 06:19 PM

Great news, but surprising. As I said I still had the reflection with eyepiece barrels sunk right to the bottom. I hope you are right...but I'm gonna need a lot of those extentions. Please continue to update. We need to solve this problem.

#21 Kent10

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Posted 10 April 2013 - 07:14 PM

I just had a quick view so it is possible there was a little light getting in but certainly it wasn't like before where I couldn't view at all.

#22 Moonglum

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Posted 10 April 2013 - 09:06 PM

Daytime I assume?

#23 Kent10

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Posted 10 April 2013 - 11:55 PM

Yes I tested while viewing the sun in the day :)

#24 Moonglum

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Posted 12 April 2013 - 08:53 AM

I am now almost certain this effect in my refractors only occurs with the 2.6X in it's position after the diagonal. With the 2.6X before the diagonal(3.4X), the 1.3 and 1.7X placed anywhere, and the Barcon placed before the diagonal, there are no unwanted reflections. I should be able to test and confirm this sometime this weekend.

#25 Kent10

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Posted 12 April 2013 - 10:19 AM

I was also using the 2.6X GPC but in the bino. I know that is the incorrect way of using it but it is the only way to use it for my Lunt LS100 solar scope as far as I know. It seems to work fine except for the bright reflections.






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