Posts Made By: Tom Masterson

Larry,

I know its been done. I think even one of the magazines did comparison testing a while back. I've searched around, and for the life of me I can't find any one spot with complete information. I found some limted comparisons by typing in "Nebula filter comparison" to my search engine. From what I've read over the years, everyone uses Lumicon as the filter to compare against and its the name most often heard at starparties. I think most reports say the differencs are subtle and can only be noticed in side by side comparisons. I've been happy with the Orion Skyglow and Ultrablock filters although I use the Ultrabock much more than the Skyglow. I also own an Omega OIII which works well too. Take my opinion with a grain of salt though because I'm a "casual" filter user. I'm sure others will offer more info.

Micheal,

I picked up a used 30mm Meade UWA for my 12" SCT and really like the eyepiece. It's a BEAST though. Size is about the same as the Nagler, maybe shorter, but it is heavier. A friend has the 31 Nagler and I found the Meade performs just as well as the Nagler in my scope.

I made up an Excel spread sheet for my scopes which lists all the details of my eyepieces such as magnification, true field, and exit pupil. When shopping for a new eyepiece I plug its specs into the spread sheet, to see how it fits. Several people suggested I try a 35 Pan as an alternative. It was a nice sharp eyepiece but I wanted the larger apparent field of view.

Steve,

I'd stick with a mono camera since you are imaging in a single wavelength. As for chip sizes, a smaller chip makes imaging smaller scale features easier since the chip gives you a higher effective magnification. I prefer a larger chip because I can always barlow for higher magnification and with a reducer you can take full or near full disk images.

The Lumenera cameras work well for h-alpha work and you can use the live preview screen for group viewing. I've never used one, but I'm sure the software has this feature. Many solar imagers use these cameras.

I've used several models of cameras from Adirondack Astronomy's line. Currently, I'm using a OEM version of thier "Voyager" USB camera. It runs off USB power from my laptop so no extra power supply is needed. One drawback with some of these cameras is that they are 8 bit so they don't have the dynamic range to capture prominences and disk features in one image. I understand a 16 bit camera is better for this. I just combine two different exposures in Photoshop. I'm looking at a program that combines three exposure into one high dymanic range image. Software like this was featured in one of the astronomy magazines last year.

A third option for you would be to buy a regular CCD camera. As long as you stick with monochrome camera that has a high shutter speed capability you'll be fine for h-alpha. You could use it for solar imaging as well as deep sky imaging too.

I second Steve's vote to go with the larger aperture.

John,

I haven't heard any report to this effect. There have been some issues with a few of the blocking filters failing much like the problem with some of the PST objectives. My filter was built in the Isle of Man which makes it one of the very early filters and it still works like new.

I go back and forth on this one. I went to a club meeting a year ago - I had not been going for quite a while and I was shocked. I walked into the room and saw a small group of "old people" sitting around talking astronomy and UFOs. Then Then realized I was one of those old people. I went away bummed out thinking the same thing - that the hobby was dying. Then I remembered a similar moment 35 years ago when I walked into my very first club meeting. Same demographics then except I was the 20 year old walking into the room of old people. They were SO excited to see someone young and I was elected president in the next elections - NEW LIFE for the club!!! Within a couple of years we had attracted new younger member - not because of me - but from public starparties and Astronomy days at a local mall - which is how I found the club. So.... big circle here. I attend a large summer starparty here in the Pacific Northwest and I see a lot of young people attending so there is hope. I bet the old people from 35 years ago were blaming TV the same way we blame the internet, cell phones and videos games for the "death" of the hobby.

Food for thought. Great question though!

Edwin,

I can't think of any reason why a barlow would compromise safety when used as you suggest. The vast majority of energy rejection is done up front in the etalon.

One issue to be aware of is using a barlow increases the size of the Sun's disk as it passes through the blocking filter. Using a 2x barlow effectivly doubles you scope's focal length, so if your scope has a 700mm focal length and the blocking filter is sized for a maximum 750mm focal length, it will now be dealing with a virtual l400mm scope which will cause vignetting.

One physical work-around is to purchase a shorty barlow so the camera doesn't sit so high above the diagonal. One device I've found handy is a multi power barlow wheel made by Seibert Optics - http://www.siebertoptics.com/SiebertOptics-barlows.html#Power Mag Wheel Barlow.

Mine gives me three different powers so I can experiment with which one works best without having to remove the camera. It's handy for night work too.

Back to your origonal question, go ahead and try your barlow ahead of your blocking filter and see how it works. It certainly won't hurt anything.

Just for giggles here's my origonal promenence image. I had the camera set to "reverse" and found I could see more detail in the image than a direct shot. I inverted the image "back" in final processing.

John,

Does the fuse/cap blow as soon as power is applied or does it take a while for them to fail? If it takes a while you might have a motor that drawing too much because something is binding up.

I can't give you any direct answers but I'll tell you a few things to try. First, look over the components very carefully in strong light using something to magnify the view. A long focal length eyepiece used backwards can be used as a loupe. Look for any bulging, blistering or discoloration of components. Also carefully look over all the small wires to be sure you don't have something pinched. There have been cases of wires being pinched on assembly only to short out sometime later.

If all looks ok, replace the fuse and cap but don't apply power just yet.

Using a flashlight unplug your dec cable and hand controller cable and check the pins in the socket to make sure they aren't bent and shorted. Just for the heck of it open the hand controller and check to see if the cap in there is blown too.

Unplug the power board from the motherboard BEFORE applying power. If nothing blows this should tell you the power panel is fine. Then try again with the motherboard plugged in but the motors unplugged from the motherboard. Then try it again plugging one motor in at a time.

Be gentle and careful with unplugging and replugging things as there are some fine wires involved.

Let us know what you find.

Go here too for tons of helpfull info on the LX200 Classics: http://www.mapug-astronomy.net/AstroDesigns/MAPUG/ArhvList.htm

Magnus,

Solar and night time observing follow the same rule. Larger aperture is better. More light = higher top magnification and larger aperture = higher resolution.

Except for cost I doubt anyone has regretted going with the larger filter.

You'll love h-alpha. It effectively doubles your observing opportunities. I'll warn you though it can interfere with houshold chores like lawn mowing.