40 replies to this topic

[Bob S.]

Why, I feel like one of the luckiest people on the planet today. A very nice fellow had what I think is one of the last thin-film I3 image intensifiers made and had only used it x3. It came via the shipper and looks to be new. I have owned three other I3's in the past including two non-thin-film and one thin-film. I missed it so much that I have been looking for a thin-film for a while and up popped this one on the other astro site. I can't wait to look at the Pillars of Creation (M16) and all of those other favorite targets. The I3 is also great for me hunting down faint stuff and aligning so I can use my MallinCam VSS colour astrovideo camera. Happy July 4th to all and what a great country we have. Even with all of the trials/tribulations we are currently enduring. Bob Schilling

[Maureen]

Congratulations Bob! You certainly know what to expect and how to use it since you've owned one before. Looking forward to reading about your observations. What scope(s) are you planning on using it with?
Happy 4th of July to you!
Maureen

[ScottAz]

Congratulations, Bob! Sure sounds like fun. Saw the ad on the other site as well, and I am looking forward to hearing how it compliments your VSS. Oh, and happy 4th to you as well!

[Bob S.]

Maureen, I have three scopes that I will use it with. The two principle scopes are an 18" f/4.2 Pegasus/Stabilite Starmaster with GOTO/Tracking and an 18" f/5 Wessling-mirrored scope. I have a very special focal reducer for my MallinCam that I may try with a Celestron CPC1100 SCT and the I3. The seller sold me an Orion Hydrogen Alpha filter that likely has a passband of 10-12nm which should be about perfect. The only other thing I will probably look for is a Denkmeir StarSweepr which reportedly will give me another f-stop in performance. With my last I3 thin-film and a 20" F/4.3 I had, we viewed 197 galaxies in one mediocre seeing night at Chiefland Astronomy Village. That incredible experience was chronicled in issue #56 of Amateur Astronomy magazine by the Editor/Owner, Charlie Warren. With the help of the Night Sky Observers Guide, he would call out a galaxy, I would punch the numbers into my SkyCommander, hit GOTO and then tell him via the I3 what the morphology of the galaxy was (i.e. spindle, edge-on, spiral, etc.). He would then come over and study it after I had had my peeks. It was an incredible night. People need to know what your IIE and my I3 can do. I think they are absolutely great and understand that if we viewed 3 nights/week for 3 hours/nightly, it would take 21 years to wear the tubes out with their 10K/hour nominal lives. Bob

[Maureen]

Wow Bob what an experience, I'm jealous!
I'm embarrassed to ask, but what exactly is a Denkmeir StarSweeper, how does it work and would it be useful in my dob with the IIE?
And yes I agree with you. People do not realize what the IIE and the BIPH can do especially, if you combine it with the right FR, filters etc.
Maureen

[Bob S.]

The StarSweeper is a focal reducer that Denkmeir came up with for their products and SCT's. However, I just realized that with my MallinCam focal reducer, the SS would likely be redundant. Bob

[Maureen]

I'm sure Doug Baum would have suggested it, if he thought it could help with my setup. He's been so helpful. Am waiting a new shorter nose piece which should get me optimum performance from my IIE which he made.
Maureen

[Bob S.]

Maureen,
We need to get you down to Chiefland Astronomy Village in North/Central Florida. Bring your IIE and I will bring my I3 and we will have some fun! Lots of friendly folks and pretty steady mag 6 skies.

[Maureen]

I went to the WSP in Feb. for the first time and will be going back. It's easy to get club members to agree to go to the FL Keys in the middle of winter. Would love to go to Chiefland but can't do the drive by myself but I'm working on it. At the WSP I had the opportunity to observe with Jack Lowenstein an older gentleman, in the true sense of the word. He had a Collins I3 and gave me lots of ideas about how to baffle, flock etc. my scope to improve the views with the IIE.

It was supposed to be clear tonight and I keep running out to check but there are mostly clouds right now. The forecast looks good for the rest of the weekend though.
Maureen

[Bob S.]

Maureen, I am envious. We have been getting the rain from the hurricane even though we are a thousand miles from Mexico? I took the 18 f/5 out with a few stars showing and tried the I3. Sob, the eyepiece wouldn't quite come to focus. I need about 1/4 of an inch of unavailable infocus. I cranked my collimation screws almost all the way up and still did not have quite enough. This is my lunar/planetary wizard and I don't know if I want to cut the truss poles? I am going to have to look at the situation in the light of day. I would really need to take off about 1/2" to get it working right.I will need a clear night to compare my eyepiece focus point with the I3 to get a sense of what to do. As you know, Jack Lowenstein was the fine gentleman that introduced me to image intensifiers in 2003 at the WSP and I have never looked back<g>. Bob

[Maureen]

Bob now I remember our on line conversation about Jack.
That's too bad about the I3 not coming to focus. I assume, from your post, that it was w/o a FR. One possible solution I had considered when trying to get mine to come to focus using a FR was, to have two sets of poles since, I was reluctant to cut my original set because some of my regular eyepieces wouldn't come to focus with shorter poles.
You might also contact Doug Baum. Can't remember the name of the product but it is made for these situations. I think it actually has a barlow in it - not sure, but I know it works.
Maureen

[Bob S.]

Maureen, Very lucky day for me. A 2" Collins I3 adapter showed up on the other astro site and the seller was kind enough to sell it to me. In the past, whenever I had difficulties with infocus, the 2" adapter did the trick. When this comes in next week, I will report on how the views are in my 18" f/5 scope. My 18" f/4.2 is under repair and when that one gets back on line, it should make the I3 even pop more due to the faster f ratio. Bob

[Maureen]

Great luck and good news. Report back please.
Try a FR with it, if you can get it to come to focus. As Doug Baum said FR= less noise although as he and others have pointed out, too much FR degrades views.
I'm currently waiting for a shorter nose piece which will allow me to achieve greater FR. I'm also considering getting a 14 nm H alpha filter to use, along with my current 9nm H alpha filter. It should also reduce noise.
Maureen

[highfnum]

before you go nuts cutting things
try zero magnification adapter

http://www.siebertop...s Adapters.html

it saved me many times

[Bob S.]

Nice advice/link. The 2" adapter I am getting for the I3 ought to do the trick. I talked with a telescope maker about cutting the truss poles and it is not something I am really excited about doing. I think I would consider the Siebert fix before cutting the poles. I really like how my 18" f/5 performs and I want to do very minimal things to it if any. I did install a Howie Glatter sling that is elegant and some encoders with arms for a DSC. Bob

[Bob S.]

Well, I had a night full of eye candy with my I3, Ha filter and a CPC1100. I know that an 11" f/10 scope is not ideal for the I3 but the views were beautiful. This latest thin-film version quickly lost any greenish hue and the views of globular clusters, nebulas and planetary nebulas were spectacular. The one object that I was hoping for more definition with was M16, The Eagle (The Pillars of Creation). I am not sure if it was the f ratio, bandpass of the Ha or both but the pillars were did not stand out that much. However, M17, M8, M20, etc. were beautiful. As Maureen can probably attest, they will have to pry my cold dead fingers from the image intensifier to get this one<g>. Bob

[highfnum]

Yup I got 3 of them !
You should try to get F/num down a little f/6 or lower

[Maureen]

Bob, my dob is an F5 and I'm using two different FR (not at the same time) to get the scope even lower. There are so many variables (size of scope, type of scope, filters, bandpass and sky conditions) that on two different nights, the same objects can look very different. This was my experience just this past week. The major difference was the transparency.
I absolutely love my IIE and easily spend 70% of my observing time using it. I am working my way through the Sharpless Catalogue.
I've spent a lot of time flocking, baffling and painting my scope. After I've had a chance to give it a good workout with my new shorter nose piece (thank you Doug!) I'll post the results.
Maureen

[highfnum]

Maureen - I bet you never look back at spending that amount
for an eyepiece -- I remember when we first meet at AOS
and you were debating the whole idea. Ive been using II since 2004. It just a whole level above even the best
glass eyepieces like televue or others - except for planets
sun moon

[Maureen]

John, you are so right. The only regret I have is not getting it sooner. It is worth every penny. I really feel like I've double the aperture of my scope. I also consider it a prosthetic device for my older eyes.
Even since I've gotten it, the views have improved because Doug has viewed with it, in my scope and has sent me a new improved nose piece which will eliminate that "space ship" effect. Doug says I will have a flat FOV. He has continued to work with me giving me advice and making suggestions.

Part of the problem was that some of my (not Doug's) extenders, filter etc. did not fit squarely into the IIE and were causing the distorted views around the edges of the FOV. The view at the center was always great.
I'm really looking forward to AOS this weekend to try it out under dark skies.
Maureen

[GlennLeDrew]

I really feel like I've double the aperture of my scope. I also consider it a prosthetic device for my older eyes.

Actually, because the surface brightness is increased to higher than can be seen without intensification, technically there is no aperture that can compete when 'old school' eyepieces are used, particularly for hydrogen emission. (Of course, not all DSOs are enhanced to a similar degree, and so the contrast gain may be slight, or possibly even worse.)

For example, an extremely faint Sharpless nebula may not be visible in any telescope equipped with a 'standard' eyepiece--narrowband visual filters included--because it's so reddened that H-alpha is the only significant emission component. The red sensitivity of the electronic aid allows to detect what is otherwise utterly beyond the capability of the biggest telescope imaginable without such amplification.

So in a very real sense these intensifiers, for certain types of objects, offer an infinite 'aperture gain.'


And I wouldn't restrict the 'prosthetic' attributes of these as being applicable only to older peepers, either!

[highfnum]

good point - never thought about it quite that way

second point - we all get old at some point unless
you know what !

[Maureen]

It's really a shame that more people either don't know about them - especially the BIPH - or have a poor opinion about them. I think it's because folks may not know how to use them optimally. So someone looks through an IIE with no filter, no FR, no light shield, etc. and they think it's not very impressive. It's as if they were listening to a Mozart symphony on AM radio with the volume turned down low. They have no idea what they're missing!
Maureen

[StarStuff1]

Agreed. The university where I work as a lab instructor purchased a new I3 in 2002. The first time I used it was during a deep space object lab. The 8-in f/10 S/C was pointed to M81 in the light glow of a small city of 50,000. Yes the galaxy was brighter but the sky glow background was, too. So much so that the view was horrible. Much better with a LPR filter that cost 1/20th of the I3.

I was turned off. Lindy's article on CN about 3 years ago got me to re-consider. The first time I used my IIE was with a Ha filter on the Winter sky 2 1/2 years ago. Wow! Now after using it IIE with a lot of different scopes and under many different conditions both with and without a Ha filter it still amazes me what it can show. You simply have to learn how to properly use this technology to get the most out of it.

[highfnum]

there is a learning curve with all things like this