Electronic Dry Cabinet for Nexstar 8SE OTA

[byang]

Hi, does anyone know which brand and model of electronic dry cabinet that can house an Nexstar 8SE OTA lying on its side (with red dot finder scope mounted)? I have searched many but most of them are the vertical types which are not suitable as the OTA will be required to rest at its end ("standing") in the cabinet. Thanks in advance!

[Sam Lee]

Previously my C8 OTA is housed in this.
http://www.reddotphoto.com.sg/ecommerce ... 22&catid=5

You can doublecheck the dimension again.

Cheers

[byang]

Hi Sam, thanks for the reply! When putting in and taking out your C8, do u have enough room to move as the internal dimension will be slightly smaller than the stated (external) dimension?

When the glass door is closed, does the lock itself interfere with the scope? I am also concerned about the space taken up by the dehumidifier unit and the adjustment knob. Hopefully there is still reasonable space to house and move the scope after taking all these into consideration. Thanks again!

Previously my C8 OTA is housed in this.
http://www.reddotphoto.com.sg/ecommerce ... 22&catid=5

You can doublecheck the dimension again.

Cheers

[Mariner]

Why insist on storing it vertically?

FYI, Celestron recommends orientating the tube vertically upwards puts the least long-term stress on the focusing mechanism from the mirror’s weight.

http://www.celestron.com/c3/support3/in ... cleid=1979

Having said that, SCTs in the forkmount confiurations (Nexstars, CPCs) are often stored by most amateurs in a vertically downward position in their mounts with no issues.

[byang]

Thanks Mariner, so when it was mentioned that "Orienting the tube vertically upwards puts the least long-term stress on the focusing mechanism from the mirror’s weight.", it means it is better to store with the corrector plate end facing vertically upward?

[Sam Lee]

???
i thought byang is asking for advise in storing the C8 horizontally?
The link to the dry cabinet is for housing a C8 horizontally.

byang, height and depth wise i don't think you will have any issues. the Fitting is not tight in these domain.
For width wise i had to remove the visual extender for it to go in nicely.
You can always measure your OTA first. The outer vs inner dimension dont really differ by too much. Minus off 2-3CMs?

After my C8 went in, i can still lock the door with plenty of allowance.

[Gary]

Why insist on storing it vertically?

FYI, Celestron recommends orientating the tube vertically upwards puts the least long-term stress on the focusing mechanism from the mirror’s weight.

http://www.celestron.com/c3/support3/in ... cleid=1979

Having said that, SCTs in the forkmount confiurations (Nexstars, CPCs) are often stored by most amateurs in a vertically downward position in their mounts with no issues.

@Mariner - Thanks for the link. Interesting read. I lol'ed at "insect invasion"!

[starfinder]

Hi Byang, Mariner:

That's an interesting article by Celestron! I didn't know there was any significance in the orientation of the OTA when storing it. I've been storing my C-5 OTA horizontally in the dry cabinet since getting it new in 1998: almost 15 years! I've brought it on obs trips to Johor and Australia; it's still pristine and works very well.

Having said that, the C-8's mirror is larger and heavier, so perhaps there's a difference.

A point of note, though: Celestron recommends storing the OTA vertically pointing upwards ("Orienting the tube vertically upwards puts the least long-term stress on the focusing mechanism from the mirror’s weight."), i.e. mirror below and corrector plate on top. I think it may be a bit tricky storing the OTA alone in the dry cabinet that way since it means that you would have to balance and rest the focuser end on the floor of the cabinet... be careful not to let it topple over!

My 12 year old Meade LX-90 has been kept mounted on the tripod all these years, with the 8" SCT OTA attached to the fork arms and pointing downwards, i.e. corrector plate below. It still works well.

Do also note the other recommendation of Celestron in that webpage: "Racking the mirror all the way to the back of the tube (clockwise or near-focus) puts the least stress on the baffle-spindle that supports the mirror's weight."

In summary, I think it's fine storing the OTA horizontally or vertically (pointing up or down); perhaps just rack the mirror in.

[byang]

Actually I m still a little confused! If the scope is stored with the corrector plate facing up, wouldn't the focusing mechanism be taking the full weight of the mirror? Or perhaps this orientation of storing is recommended if the scope is kept mounted? If the scope is not mounted then it is fine to store horizontally or vertically with corrector plate facing down.

I am not quite sure if anyone would want to store with the corrector plate facing up as this in a state of inequilibrium. But maybe this is possible with the use of the packing foam but nothing was mentioned about using the foam for this purpose I believed?

And whats the meaning of racking the mirror in? Sorry for my poor english!

[starfinder]

Hi Byang, as I said, it would indeed be tricky trying to store the OTA alone with the corrector plate facing up. So I think don't bother doing so, and in fact there is a large risk of it toppling over if stored that way.

Based on my own experience with both Celestron and Meade SCTs (5", 6" and 8"), there shouldn't be any problems with storing OTAs of these sizes in any orientation. I suspect Celestron's advice is more pertinent to the larger OTAs such as 11", 14" etc, where the mirror is much more massive.

Fyi, Celestron explains racking the mirror in as "Racking the mirror all the way to the back of the tube (clockwise or near-focus)...", i.e. turn the focuser in the clockwise direction. However, I've also not racked the mirror in all these years when storing, with no issues, so I think, don't even need to bother about that.