How do you stop the dew on a Dobsonian telescope?
To keep something dew free you just need to keep it above the dew point – it doesn’t follow that it has to be warm to the touch. So long as your equipment remains even a few degrees above ambient temperature, it will remain dew free.
Does a Dobsonian need a dew shield?
But again, dew is not the reason to use a “dew shield” with most Dobsonians. It is for ambient light control. We can likely DIY one quite similarly. You just need to find the right material with the proper combination of stiffness and flexibility and then sew on a velcro strip (the sewing is the biggest problem I see).
How do you remove dew from a telescope?
When dew forms on the lens of your telescope, you can try to heat the lens to get it back above the dew point. If you have access to electricity, you can do the job with a gentle flow of warm air from a hair dryer. Repeat when necessary.
How do I stop condensation on my telescope mirror?
To prevent condensation lock the cold outside air in around the primary with some kind of airtight covering before you bring it in. The cold outside air will be much drier than the inside air (warm air holds more moisture). When the mirror has warmed to inside temps, you can remove the covering if you wish.
Do I need a dew shield for my telescope?
Reflector telescopes do not require dew shields because the primary mirror is located at the bottom of the optical tube, and the tube acts as a natural dew shield. Dew Shields essentially extend the tube of the telescope.
Do Newtonian telescopes need dew heaters?
Newtonian Reflectors do not need a heater on the primary mirror but do need a heater on the secondary mirror. Heaters are also needed for the other optics such as eyepiece, finderscope, and Telrad.
What does a telescope dew shield do?
Steve says: “Dew shields are metal or plastic extensions to a telescope’s optical tube. They serve two functions; to stop stray light entering the light path from oblique angles and to help keep dew at bay.
Is dew shield necessary?
As has been pointed out, SCTs and Maks are “dew magnets”, their exposed correctors radiate heat, a dew shield or heater is mandatory.
Why does my telescope fog up?
If your telescope is warm and the air outside is cold, the moisture in the air is going to condense on your telescope, leading to dew and poor seeing. By ensuring your telescope isn’t significantly warmer than the ambient air, you reduce the chances of dew forming.
Does a reflector telescope need a dew heater?
Reflector telescopes do not require dew shields because the primary mirror is located at the bottom of the optical tube, and the tube acts as a natural dew shield.
What does a dew shield do?
Where should a dew heater be placed?
The correct location is around the telescope tube just behind the dew shield. Since the lens cell is mounted to the tube some of the heat will conduct to the lens and the rest of it prevents the tube from being cooled by the night sky and stealing heat from the lens surface inside the tube.
Do you need a dew shield for a reflector telescope?
Why do I need a dew shield?
Using a Dew Shield A dew shield blocks stray light from entering the telescope lens, and can also protect it from any dust and dirt in that is stirred up around the telescope.
Do I need a dew shield?
A dew shield can effectively delay the process of dew forming on your optics, but it won’t stop it completely. It reduces the angular amount of sky seen by the telescope objective and can keep moisture at bay for an extended period of time.
How much power does a dew heater use?
This dew heater is designed to be powered and controlled directly from the EAGLE but it can also be connected to any 12V external power source with RCA connector. Power consumption is 670mA.
Do I need a dew heater controller?
Basically, you’ll need a dew heater band for each telescope, camera lens or eyepiece you want to keep dry, and a controller with a power source to turn them on.
Where should I put my dew heater?
A dew heater band should be wrapped around the base of the objective lens, at the bottom of the dew shield (if applicable). The same applies when using a dew heater strap with a small camera lens.
What is a Dobsonian telescope?
For one, Dobsonians are a type of reflector telescope, meaning they use mirrors to form an image, and these mirrors need to be frequently aligned. This process is known as collimation, and it’s similar to having to tune an instrument before playing it.
How do I choose the best DOB Smithsonian telescope?
Go-To Dobsonian Telescopes are a great choice for those who might be a little daunted by the idea of having to manually point and track the telescope. Most Dobsonians feature an all-manual design, so you have to find objects yourself and keep them centered in the eyepiece by continuously moving the telescope slightly.
Are Dobsonians good for astrophotography?
Second, most Dobsonians are entirely manual, meaning they usually don’t have computers or motorization to point at targets for you automatically. Some Dobsonians have this go-to ability, but come with an added cost. Third, Dobsonians make for below-average telescopes for deep sky astrophotography.
How big is the aperture on a DOB telescope?
It has enough aperture (5 inches) to see brighter galaxies and other deep-sky objects as well as the Moon, Saturn, Jupiter and Mars, and the tube collapses down to shorten it by half. Just set this portable Dob on a picnic table, insert an eyepiece, and gaze at the wonders of the Universe!