Posts Made By: Donald Durbin

Well so far I can say that I am very pleased with the 45 Elites. As you can see from the image, I have a Williams Optic crayford focuser with a Williams Optic 2" diagonal. When you add in the 45mm Elites that is an awful lot of extra length but the Celestron 9.25 can still focus.

I was beginning to think it would be another wasted night when I got a peek at the moon. Once I started tracking it I was able to keep viewing without too much problem.

It did actually clear off for a short period. The clouds have rolled back in now. I am hoping for a look at M42 later tonight.

The detail through the 45mm Elites is amazing. Near the south pole of the Moon is a peak that is almost always in light. It looks like a little light house because it sticks up out of the dark terminator. I always look for that. Below the light house there are a few medium sized craters. I know they all have names and I do not know which is which. In one of the craters I could see some small impact craters with the 45 Elites. When I pulled out the binoviewer and put in a single eyepiece I could not see them. Switching back to the binoviewer the small craterlets where still apparent. I did this 3 or 4 times. I could definitely see more detail with the binoviewers. It must be the increased size that a binoview gives you. A binoviewer cannot give you any more resolution over a single eyepiece. However, after this experiment, I can definitely say I cannot see where I am loosing any resolution with the binoviewer.

My Orion 32mm Optiluxe eyepieces were a little disappointing. They have a kidney bean effect that seems a little worse with the binoviewer. I could use them but I had to hold the tops of the eyepieces and touch my forehead to maintain the perfect distance. The older shorter Orion Optiuxe eyepieces do not seem to have as much of a problem as the newer ones. I have one 40mm and one 32mm of the older type. I like them much better. I even put them both in at once and I was able to merge the images. How weird is that??? It is not something that I would recommend for extended viewing.

The Clouds are clearing off again. Hopefully I will get my view of M42 tonight.

Don

I finally got some decent sunlight and I thought people might be interested in this.

Using the method invented by Tom Hole I measured the clear aperture of the 45mm Elites. I taped paper over the eyepiece holders and held the binoviewer up to the Sun while holding a digital caliper in the other hand and measuring the illuminated circle on the paper. This circle measured between 38mm and 39mm. This indicates that somewhere in the binoviewer the Clear Aperture is being cut down a little from the 45mm clear aperture at the base of the binoviewer. I measured my original Black Nights using the same method and got between 21mm and 22mm.

This is still the largest Clear Aperture of any Binoviewer recorded to date that I have heard of.

Don Durbin

Hi All,

I bought a Digitec star collimator and Artificial Star to help me
align my Meade 152ED.

I find that I get a nice set of diffraction rings in one direction
and a fuzzy blob in the other direction. Does anyone know why this
would be? Is this something that I can correct?

Thanks
Don

There is more than cost to consider when contemplating the purchase of a 2" binoviewer. You should also consider weight.

The standard 1 1/4" Black Night binoviewer with diopters weigh 22.2 Oz. The 45mm Elites with diopters weigh 35.4 Oz.

Since an SCT needs no OCA to get either of these units to work, lets say we decide to use a pair of 26mm EPs in our SCT. If we are going with 1 1/4" Black Nights(22.2) and a pair of Meade Super Plossls (8.4) we have a total weight of 30.6 Oz. at the end of out telescope.

If we go with the 2" 45mm Elites(35.4) and a pair of Celestron E-LUX 2" 26mm(23.2) we now have a total weight of 58.6 Ox. on the end of our telescope.

I also checked my Nagler 12mm Type 2 Eyepieces. The pair of them weighed in at 34.2 Oz. To protect the optical window at the base of the eyepiece holder when using these or other eyepieces that fit both 1 1/4" & 2" holders you should add in the weight of an adapter. Sieberts has some nice ones that only weigh 1.5 Oz. each. That makes the total for the 12mm T2 Naglers, adapters, and 2" 45mm Elites a hefty 72.6 Oz.

I also had some lighter weight and less expensive eyepieces made by Gary Russell. The pair of 19mm SWA Konigs weigh 10.6 Oz. and my 16.8mm SWA Konigs weigh 10.2 Oz. I will say that I have been happy enough with these EPs that I contacted Gary and ordered a pair of 11mm and 22mm EPs from him. He is going to match them for binoviewing for me. At less than half the weight of the E_LUX and a third the weight of the Naglers, these EPs are something to consider. The price is also very reasonable.

You are probably going to have a diagonal on the back of your SCT anyway, but, I was in a weighing mode. I checked 4 different brands of 2" diagonals I had on hand. I found my William Optics diagonal had a weight of 14.4 Oz. and was the lightest diagonal I checked. The Antares 2" diagonal weighed 18.4 Oz. and was the heaviest I had. A standard Meade 2" diagonal weighed 16.4 and a Generic Japanese no name weighed in at 16.8 Oz.

When using the 45mm Elites the other night I found that my C9.25 tracked very well on my SkyView Pro Mount. I also do not expect any trouble with my Meade 152ED on my LXD-750 mount.

I am not trying to scare anyone out of buying a 2" binoviewer, I am just trying to get some numbers out there so you can make an informed decision.

Don Durbin

Some of us are aware of the ability to reach focus with a binoviewer without the use of an OCA/OCS and diagonal. The binoviewer is inserted directly into the refractors visual back. This is only possible with some refractors. My Stellarvue AT1010 will reach focus with a 1/4" to spare for terrestrial viewing when using my original Black Night binoviewers. Focusing on Astronomical object requires more in travel and will not work even with the short length of the original Black Nights. I could not reach focus on terrestrial objects using the 45mm Elites with this method.

I used the same 1 1/4 eyepieces in the 45mm Elites as I used in the original Black Nights for these tests.

If I add in a diagonal and place an UltraBarlow on the binoviewer,(This is similar to a powermate in design) I can focus on terrestrial objects with the original Black Nights with an 1/8" of in-travel to spare. The 45mm Elites still do not reach focus.

If I place the UltraBarlow directly into the telescope and then add the diagonal, both the original Black Nights and the 45mm Elites come to focus at the end of the focusers travel. A Stellarvue AT1010 focuser has 4 inches of travel. At least that is what I measured on mine. Since Astronomical objects require more in-travel this arrangement will work for planetary and deep space viewing.

Interestingly if I use a two inch extension in back of the UltraBarlow before the diagonal it does not change the point of focus on either the original Black Night or the 45mm Elites. If I place the two inch extension first followed by the UltraBarlow and then the diagonal I end up with the terrestrial focus point for both the original Black Night or the 45mm Elites a full 2" in or dead center in my focusers range.

Another very good reason to place a barlow or powermate before the diagonal is that it puts less stress on the diagonal and less weight on the extended moment arm.

I am sure I am not the only person who has seen a diagonal or the visual back on the scope slip or unscrew and watched as my binoviewers and eyepieces flipped upside down. Not a good thing to see on a full stomach.

In my next post I will add the Sieberts focal reducers into the mix. I need to go out and buy a pair of yard sticks so I can show magnification factors.

Hi all,

This morning I got up a little before 7:00 am here in Ohio. I stuck my head out the door to see how the skies were. It was crystal clear and I had a easy view of Venus Jupiter and a half moon.

I had left my Skyview Pro mount outside last night after using it with my C9.25 and the 2" Binoviewer. (Just the mount head and the tripod. All the electronics except the motors came in for the night.) I grabbed my Stellarvue AT1010 and a 15mm plossl and headed out the door.

I was able to setup quickly and I got a nice Cyclops view of Jupiter. I immediately went back inside and grabbed my 22mm Black Nights, a pair of 15mm Televue plossls, and a Sieberts 1.3X OCA I keep a Lumicon diagonal attached to. I also had a two inch moon filter on the other end of the OCA. It seemed to help darken the field of view.

I popped the OCA with diagonal into the Stellarvue and attached my Black Nights. I really could have wished for a lot more power but the view was pretty nice and even through it was almost dawn some bands on Jupiter were clearly visible. I decided against running back in the house for more EPs. It was really getting lighter by the second. As the detail of Jupiter faded I switch over to a nice full view of the half moon. I was glad I had the moon filter on the OCA.

This is definitely a case where I wish Harry Siebert had my Zoom OCA ready. I could have fine tuned the power to the perfect setting.

All in all it was a good but short session. The sky got bright very quick and I was suddenly away of how cold I was. I took everything back inside and checked the outside temperature. It read 23 degrees.
8O
Don Durbin

Hi all,

I have not yet put the 45mm Elites to the test on my half of the Orion XT10 I own with my nephew, but as of tonight I have used the 45mm Elites with my Orion Atlas 8". I have this scope on a Talscope pier. I got the last one of these before Talscopes in Canada stopped selling them.

I have now used my 45mm Elites on my C9.25, my Meade 152ED, my Stellarvue AT1010, my pseudo Meade 90mm refractor, and my Orion Atlas 8".

The C9.25 is easy, you just plug the 45mm Elites into the scope and focus. The other scopes need a little help and that is where the Sieberts Multimag comes in. It can be configured to work with a refractor or a Newtonian reflector. I have it configured in the Newtonian mode right now for the Atlas 8".

The Multimag comes with a 1.2x and a 2.0x power lens that can be combined for a higher power. Each of these combinations can be used with the focal reducer giving you a wide range of combinations.

So far I have only used the 1.2X with and without the focal reducer configured for both refractors and Newtonian reflectors.

The Multimag is a complex unit. I have my crossed yard sticks ala Tom Hole and I plan to do some real magnification measurements sometime soon.

The biggest draw back that I can see with the Multimag is that it is not something that you can easily reconfigure in the dark.

Don Durbin

Hi All,

If you look at the subject line there are 10 exclamation points in the title. The reason is this news is a definite '10'

On the Binoviewers-And-Eyepieces-Unlimited group Harry Siebert announced that he is actively working with Russ at Denkmeier to develop a version of the Denkmeier Power Switch Diagonal for use with Siebert 2" Binoviewers. 8O

Below is the link. 8)

http://groups.yahoo.com/group/Binoviewers-And-Eyepieces-Unlimited/message/253

The postmaster kicked back two separate emails that I attempted to send to BuyTelescope.com. Other recipients received the email.

I know your not officially BuyTelescope.com but I thought I would mention the email problem anyway.


Don Durbin

Just thought I would give a first impression of the 2" Denkmeier Power Switch diagonal. So far I have only used it for terrestrial viewing.
Let me also say the Denkmeier site specifically says, "Allows 3 Magnifications With Any Single Eyepiece". It makes no mention of use with a binoviewer. My attempts to use a binoviewer are outside the intended scope of the device.

This device is made for use with an SCT so I checked it out with my Celestron 9.25. I use a Williams Optic crayford focuser with that scope and a Williams Optic 2" diagonal.

For the first test I replaced the diagonal with the Power Switch Diagonal. I started out with a 40mm Optiluxe. That seemed to work pretty well in the X2 mode and in the focal reducer mode except for the secondary shadow. ( I later found that going much over 30mm with the focal reducer resulted in a very visible secondary shadow.) After using the 40mm in Cyclops mode I put in the 2" binoviewers. They worked with the X2 mode but it was probably more like an X3 or X4 mode with the added length of the binoviewer. The focal reducer mode could not reach focus.

The Power Switch ships with a 2" compression ring visual back that is pretty nice. This is a compression ring 2" visual back with dual tension screws for a very stable grip. I decided I would remove the crayford focuser and try the power switch with just the 2" visual back that came with it. Once again the single eyepiece worked fine but was really limited to 30mm or less when working in the focal reducer mode. The 2" binoviewer would not focus in focal reducer mode. I switched to the older shorter 1 1/4" BlackNight binoviewer. The result was the same. I could not reach focus in focal reducer mode. I was really hoping to use the F/6.6 focal reduction with the binoviewer. The 1 1/4" Blacknight has a very short light path so this device as it was shipped to me would probably not reach focus in focal reducer mode with any binoviewer currently on the market.

Even though the focal reducer mode does not work with my binoviewers, I am still looking forward to work with the switch in its original configuration using my Meade DSI camera.

The bottom line is that the Denkmeier Power switch works as advertised with a single eyepiece and it is handy having three powers with the same eyepiece by throwing a switch and doing a little refocusing. The amount of refocusing was less than I expected. When switching from plain mode to X2 or to focal reducer mode the target I was using was still visible. I think I turned the focus knob about three rotations in either direction. The 30mm limit on the eyepiece was a bit of a surprise, I was hoping for much wider views. I would like to try this device on the my clubs 16" SCT and see what power can be used in an F17.5 scope.

The device is a well made optical quality unit and it a great addition for your SCT when used with a single eyepiece with 30mm or less focal length. Comparing it to my Williams Optic diagonal it is extremely similar in appearance. You might also notice that the 1/10th wave 97% reflectivity is also identical in both units

If and when the temperature ever come up above freezing I will use my yardstick target to determine the actual powers of magnification with this device.

Don Durbin