James Paulson's roll off roof observatory at the Sunridge Observatory site, taken in the summer of 1986, housing a 10 inch f/5 Cave Astrola Newtonian reflector telescope

Tuesday, September 29, 2009

Basic Piggyback Astrophotography

Here is a photo of my SN6 on the LXD75 mount along with it's custom built accessory bracket shown with my Minolta X-370 35mm SLR mounted on it in piggyback mode. This is my entry level deep sky imaging system.

How often do we read that astrophotography is hard, expensive, and really cannot be mastered without a lot of time and effort. If this was the truth, many people, myself included would have never ventured into attempting it in the first place. Yes astrophotography takes some time to learn, and yes, at the upper end prime focus and afocal methods of imaging, it can become a bit more complex as guiding and mount stability become issues that limit the quality of the images one can produce.

But piggybacking a camera on an equatorial mount is actually a very enjoyable method of learning deep sky imaging, and is neither difficult nor time consuming and can produce some excellent results. Any mount that can track images in a scope fairly accurately will suffice for a setup like the one pictured, which uses a 50mm lens at f/2. Accurate polar alignment is important to avoid field rotation, and with lenses of focal length greater than 200mm, guiding may become an issue as well. But using modern technology, it is possible to simply use the main scope as a guidescope using something like the Meade LPI or DSI (I, II, or III) using PHD guiding if that becomes necessary.

Beginning with a setup like this will deliver you very satisfactory results. I have been using this type of setup for years using high speed film and have produced excellent images of the Milky Way and its structure, and I plan on using the exact same setup with my DSLR to produce similar and better results.

I encourage others who are interested to begin this way and give deep sky imaging a try.

Wednesday, September 23, 2009

Population II Amateur Astronomer

How would you feel if you went to bed one night and woke up the next day in a strange and alien world? All your preconceived notions about gravity, physics, the daily operation of life had suddenly changed?

Recently I got into a debate about focal ratio and I thought I knew what I was talking about. I'm an old school amateur raised on old school ways with lots of formulas and a strict adherence to laws governing systems and how they operate. All of this was predictable.

Well apparently the rules have changed when it comes to light collection technology and focal ratio no longer determines how a CCD collects light. The only thing that matters is aperture and because of the nature of sky glow and the efficiency of detection technology, slower scopes may actually be more efficient because they collect more total photons due to integration time. I find it absolutely mind-boggling that something so rooted and perfect is suddenly tipped upside down and forever destroyed, to be relegated to obsolesence, supplanted by superior advancements in technology.

I know that this may have little impact on your world, and if you are new to this the old ideas may not even be relevant because you have never experienced them. But I somehow can't leave this without taking one last jab at these hot young imaging experts - the real world real dollar value of a 400 lb Astrola mounted 10 inch f/7 Cave just went up fourfold. It's time to dust off the relics because what is old is still what is new.

Wednesday, September 16, 2009

My Road Ahead

I am really wanting to get into doing deep sky photography again. The more I read about imaging, the more confusing it all seems, and in some ways, this is a quantum leap from the grand old days of focus, guide and print. I am wanting to invest in a Canon DSLR and begin simply by doing some widefield imaging piggybacking a camera on the SN6. The basics of it all seem pretty straightforward, but as I read more and more of the technical side of aquiring images, flats, darks, lights, etc, this all looks like a lot of learning with software, and software is something that I really need to spend more time learning.
I'm not one to be intimidated by technical things, but I have to make a beginning somwhere, and this seems like a logical step. And besides, I need a decent digital camera anyways, so this gives me a chance to cover my bases and get back into the things I enjoy.
I really feel that if I can learn this, anyone can.

Monday, September 7, 2009

Your Basic Powertank

Here is the new powertank that I built today. Most commercial units cost about the same but after reading all the stories about the short battery life on them, I decided I would rather make my own. Equipment to make one includes 1 Group 24 Battery Box (Walmart), 1 3 LED Clearance Light (Walmart), 1 inline blade fuse holder (Walmart), 1 toggle switch (Advance Auto), 1 weatherpoof 12 volt receptacle (Parts City), and 2 color coded battery terminals (Advance Auto). I've not put a battery in mine yet but will be choosing the Walmart 75 amp hour deep cycle to install in mine. The light is wired into the toggle switch so it can be turned on and off as needed. The purpose of the light is to provide some visibility to the scope and equipment when people are around or near the telescope, and to assist in setup and teardown. This little unit will give me all the power I need for running the scope, and a dew heater, and I have designed it to allow for additional 12 volt outlets to be added. This unit will be wired into my camper's solar system and kept charged fully at all times. No more trips to the store once a month to buy $10 worth of battery's. And with power to spare, it improves the ability of the slewing motors to perform smoothly in the Winter months.