AstroZap Dew Heaters at First Light Optics

[FLO]

First Light Optics has become the UK importer of the US manufactured AstroZap range of accessories

Like most American companies, AstroZap have a passion and enthusiasm for their product, service and communication.

Their range of accessories neatly fills several gaps in FLO's product range:

Today I have added their Flexible Dew Heater Strips. In use, they are wrapped around the telescope tube, near the optics, and secured with velcro/elastic. A gentle and even heat is then transferred to the optics until the temperature is slightly warmer than the dew-point. Printed circuit technology ensures even heat distribution and low power consumption. Each strip is supplied with a standard six-foot cord and phono-plug connector for 12-volt operation.

FLO's prices are based on the US selling price plus UK VAT/Duty. This makes them competitive in a market currently dominated by Kendrick and DewNot.

For example, an 8" Heater Strip for a Celestron/Meade SCT would cost (3rd May '07):

Astrozap: £29.50 before SGL discount

Kendrick: £29.80

DewNot: £35

AstroZap are also well known for their range of Flexible and solid Dew Shields (including one that combines a Dew Heater), light-shrouds for the Meade LightBridge Truss Dobsonian, Solar Filters and metal Eyepiece Trays. These will all be added to FLO's website soon and announced here.

SGL Discount will apply to the entire range 8)

Thanks for looking.

[Ant]

Hi Steve,

These look GREAT!

How much current do they draw.

I was thinking about the 1.25" & finder and then maybe a 2" EP one for the camera lense (will have to measure first).

I run a 5amp supply to the mount. So really need to know how much they draw!

Ant

[James]

This is good news - I can retire my well used 12v hairdryers which aggravate the neighbours and nearby campers if I'm camping!

[FLO]

Thanks chaps

Should have technical specs soon Ant.

[daz]

Steve

I notice there is no secondary mirror heater. Do they do one or planning to??

[Ant]

Sorry Steve, what would the lead time be?

[FLO]

Daz, will look into the secondary heater in the morning.

Ant, initially it will take approx 1 week for delivery. However, I shall be holding stock of the more popular products/sizes, which can then be dispatched same-day.

[Jamie]

Nice one Steve.

Sounds like another winner for FLO...

[Ant]

I think that these are going to be really good.

Especially with delivery that quick, and prices that good.

I think that I'll need at least 2, no make that three. 50mm Finder, 2" EP for camera and 3" one for the refractor.

Ant

[daz]

Thanks Steve

[FLO]

Here y'go Ant:

1.25” eyepieces and 50mm finder:

6.5” (16.5cm) length, 3.1 Watts, 0.25 Amps @ 12V

2” eyepieces:

9” (22.9cm) length, 4.2 Watts, 0.35 Amps @ 12V

3” telescopes:

13” (33cm) length, 6.0 Watts, 0.50 Amps @ 12V

[dogfish]

Hi Steve

This may be a dim question, but if I'm only running one of these, do I need the controller? I've seen claims that the DewNot tapes can work without one, but I'm a bit suspicious of this as I can't understand what's controlling the temperature/thermostat range (assuming that's one of the jobs that the controller does).

Cheers, Martin

[James]

Martin posted just as I was about to post the same question...

[FLO]

Its a good question. Ideally, the heat should be controlled otherwise you could waste energy. In practise, you switch the controller to half-way and leave it a while to see how much dew is removed, if there is still a patch in the centre of the optic you increase the heat until it is gone. This way your battery lasts longer and the optic is only as warm as it needs to be (slightly above dew-point). There are a number of Dew Controllers and FLO will be putting some into stock very soon. AstroZap Dew Heater Strips are compatible with all good controllers including Revelation, Kendrick and Thousand Oaks.

Some do use the the purpose-made 12V DC Lead to connect the tape directly to the power-pack. In doing so, the tape is running on full-power. This won't harm the tape (can't vouch for other brands) but it might result in the optic being warmer than necessary which might effect the view and will waste energy.

UPDATE: Astrozap and Kendrick Dew Controllers now in stock

[dogfish]

Hi Steve

Thanks for the info. I take your point about getting the scope too warm (introduce air currents?), but the controllers I've seen on other sites seem pretty pricey. I wonder if you could unplug it for ten minutes or so, every half hour, or would this just make things worse (temperature yo-yoing up and down)? I'm less worried about power consumption (apart from the effect on the environment), as the 12v 55ah leisure battery that I have seems to run for days on end without re-charging.

Martin

[FLO]

Thanks for the info. I take your point about getting the scope too warm (introduce air currents?)

Thats the theory but in practise, it doesn't appear happen (?).

In normal use, the heater raises the optics temperature to 1° - 2° above the ambient air temperature, which is definitely not enough to effect seeing.

I wonder if you could unplug it for ten minutes or so, every half hour, or would this just make things worse (temperature yo-yoing up and down)?

That's how some controllers work, by switching the power on/off/on/off. Though I am guessing the delay between switching is less than half-hour.

[dogfish]

Thanks again Steve. Expect a call after payday

[FLO]

I notice there is no secondary mirror heater. Do they do one or planning to??

Daz, there are no plans for a secondary heater.