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Old 06-10-2020, 08:10 PM
Spacepirate (Adam)
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My first noobtacular question: zoomification

Good evening folks.

I am completely new to astronomy and astrophotography. My better looking half bought me a nice shiny telescope (https://www.celestron.com/products/n...on-8-telescope), with a few eyepieces (6mm, 13mm, and 40mm).

Finding Mars is easy enough. But all I see is a bright white dot, with any of those eyepieces, even when I get the sharpest focus.

Am I doing something obviously wrong?
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Old 06-10-2020, 08:26 PM
sunslayr (David)
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Mars is quite small you might need at least a 2x Barlow with your highest magnification eyepiece (6mm) to see detail, take at peek at Jupiter or Saturn in the early evening, it should give you better view if planets is what you're after.
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Old 06-10-2020, 08:39 PM
raymo
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Are you sure that you are looking at Mars? With a focal length of 2032mm
your 6mm eyepiece will give a mag of 338x, more than enough to see it as
a small disc, and it should have an orangey tint.
raymo
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Old 06-10-2020, 08:47 PM
astro744
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Mars should be a distinctly orange disk even with the 13mm eyepiece. The 6mm on your telescope requires exceptional seeing which with current weather on the east coast is not happening. You also need to allow the telescope to come to ambient temperature.

If you’re seeing a white dot it could be another target although I have heard many a beginner describe Mars as a white blob. Colours are subtle but Mars is definitely orange. Try the other planets two bright planets directly overhead early evening, namely Jupiter and Saturn.
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Old 07-10-2020, 01:25 PM
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mental4astro (Alexander)
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Hello Adam,

to IIS!

As has been mentioned, Mars, all the planets for that matter, are always going to appear like a small dot. Never will they appear as a big round ball like the Moon - they are just too far away. This is often a big trap for newcomers to astro who have no experience with telescopes other than what they see on the TV.

However! The same amount of detail can be seen through an eyepiece, but it means giving your eyes a little time to adjust to looking through an astronomical telescope. We are all accustomed to using our eyes in bright light, but using an astronomical telescope is a totally different proposition, and we actually need to learn how to see again! And with the planets, because they are bright & small, and set upon an ink-black background the image is a high contrast one, the details on the planets are low in contrast, and we just need to be patient with our eyes so they can come to terms with the new situation.

I have started a thread that talks about how to view the Moon and planets, giving tips and pointers on how to make the best use of our HUMAN eyes and do's & don'ts in making the most of your scope - and there are a lot of conditions that affect how the image appears through the scope, many of which are totally out of our hands to control:

Observing the Moon and planets - the good juice and cheats

I have also started another thread specifically about nebulae, but what it discusses applies to all other deep sky objects:

Understanding nebulae - what it is you are looking at

And a third thread aimed specifically at the bane of all newcomers to astronomy, galaxies:

Observing galaxies - where are they??? A how and why guide

Adam, you have a very capable scope and mount set up. The challenge for you is learning how to see again! So just be patient with the scope AND yourself. The details are all there.

Alex.
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Old 07-10-2020, 01:43 PM
Spacepirate (Adam)
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Thanks for the replies. It's refreshing to find an internet forum with helpful people and not snarky punks.

Yes, it's definitely Mars. Easy to find as it's near our moon.

I didn't leave the telescope outside to cool down. I'll leave it out for a while before I use it again, when this weather clears. Thanks for that suggestion.

I have a 2x Barlow, so I'll see how that affects things.

My next task is setting up tracking, software, and my camera. I'll read around the threads here first.

Thanks folks.
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Old 07-10-2020, 01:47 PM
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mental4astro (Alexander)
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Adam,

With the 6mm eyepiece you have, forget about the barlow. That eyepiece will pretty much give you the maximum practical magnification your 8" scope can give you before the image starts to degrade, and the barlow will not help you at all. I suggest you read that first link I posted to observing the Moon and planets, especially its first two entries - it will explain why.

Alex.
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Old 07-10-2020, 02:12 PM
astro744
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Note Mars was near the Moon a few days ago but the Moon has moved quite a bit in its orbit since then. Get your self Stellarium for the PC (free) or the basic Sky Safari app (purple not red is free) and you can see what is up where and when. Enjoy!
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Old 11-10-2020, 04:06 PM
Renato1 (Renato)
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Firstly - let your telescope cool down outside for half an hour - can make a big difference to sharpness.


Secondly - make sure you aren't looking over someone's house with lots of heating going on in it. If necessary, wait several hours till Mars moves further along the sky. Similarly, if stars are twinkling a lot, don't expect sharp views.

Thirdly - use a red filter, or put red cellophane over your eyepiece. Markings on Mars easily show up. Then - strangely - after awhile you may find like I did that I could spot the markings on what previously looked like a white blob.

Some years there are dust storms on Mars, and you can't see anything much no matter what you do.

Good luck.
Regards,
Renato
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Old 13-10-2020, 05:56 PM
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mental4astro (Alexander)
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Quote:
Originally Posted by Renato1 View Post
Firstly - let your telescope cool down outside for half an hour - can make a big difference to sharpness.
There is a different take on this today when it comes to SCT's and Maks.

Instead of having the scope cool down, DON'T let it cool down!

The problem of heat in an SCT and Mak is the metal or carbon fibre tube cools down quickly, but there is a big thermal mass inside the OTA - the glass mirror and baffle tube. So what happens when the tube cools, a heat plume is generated inside the OTA. This means that if you want to use your scope after setting up, you may need to wait anywhere from an hour to several hours depending on the temperature differential between the scope and night time temperature, and also the size of the scope.

By not letting the scope cool it is done by insulating the OTA. Insulating the OTA, the heat plume is prevented from being generated, meaning that the there is no need for a cooling period for the scope and it can be used at high magnification as soon as it is set up. Of course, the scope is still cooling down, but it is the rate of cool which has been dramatically altered, there by preventing the heat plume to develop.

I have been insulating my SCT's and Maks for several years now. I use these scope from home where I don't have time to set up and wait for two to three hours for the scope to cool down. I will typically only have two to three hours with a scope, and pulling one out is next to always a spare of the moment decision. Then certainly there is no time for waiting for the scope to cool down. Yet by insulating these closed tube instruments, I can crank them up to 400X as soon as it is set up - the only caveat is the prevailing seeing conditions - and no time lost to a cooling period.

There is an added bonus to insulating an SCT or Mak - it helps keep the corrector plate dry from dew for longer.

Insulating the OTA won't necessarily prevent the corrector from dewing up, particularly an SCT corrector as it has so little mass to it. My backyard sees more nights with heavy dew than dry nights. I have had both my insulated SCT's and Maks dew up on some night when conditions were especially heavy. I have also come up with a way of keeping my SCT's and Maks dry regardless of dew - by installing a small 12V fan into the side of the dewshield end of the insulating wrap. No need to use heating straps for dew control as heating straps add the very thing we have been striving to avoid - heat.

You will find more information on insulating SCT's and Maks and the use of a fan here:

SCT & Mak total dew control without heat - a solution!

The first pic below shows the insulating wrap I made from an old yoga mat for an SCT. The second pic shows a naked 7" Mak, then the same Mak with its wrap made from Coreflute. The last pics show the small 40mm fan installed into the side of the dewshield end of the wrap.

Alex.
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Last edited by mental4astro; 13-10-2020 at 06:11 PM.
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Old 13-10-2020, 11:50 PM
Renato1 (Renato)
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Quote:
Originally Posted by mental4astro View Post
There is a different take on this today when it comes to SCT's and Maks.

Instead of having the scope cool down, DON'T let it cool down!

The problem of heat in an SCT and Mak is the metal or carbon fibre tube cools down quickly, but there is a big thermal mass inside the OTA - the glass mirror and baffle tube. So what happens when the tube cools, a heat plume is generated inside the OTA. This means that if you want to use your scope after setting up, you may need to wait anywhere from an hour to several hours depending on the temperature differential between the scope and night time temperature, and also the size of the scope.

By not letting the scope cool it is done by insulating the OTA. Insulating the OTA, the heat plume is prevented from being generated, meaning that the there is no need for a cooling period for the scope and it can be used at high magnification as soon as it is set up. Of course, the scope is still cooling down, but it is the rate of cool which has been dramatically altered, there by preventing the heat plume to develop.

I have been insulating my SCT's and Maks for several years now. I use these scope from home where I don't have time to set up and wait for two to three hours for the scope to cool down. I will typically only have two to three hours with a scope, and pulling one out is next to always a spare of the moment decision. Then certainly there is no time for waiting for the scope to cool down. Yet by insulating these closed tube instruments, I can crank them up to 400X as soon as it is set up - the only caveat is the prevailing seeing conditions - and no time lost to a cooling period.

There is an added bonus to insulating an SCT or Mak - it helps keep the corrector plate dry from dew for longer.

Insulating the OTA won't necessarily prevent the corrector from dewing up, particularly an SCT corrector as it has so little mass to it. My backyard sees more nights with heavy dew than dry nights. I have had both my insulated SCT's and Maks dew up on some night when conditions were especially heavy. I have also come up with a way of keeping my SCT's and Maks dry regardless of dew - by installing a small 12V fan into the side of the dewshield end of the insulating wrap. No need to use heating straps for dew control as heating straps add the very thing we have been striving to avoid - heat.

You will find more information on insulating SCT's and Maks and the use of a fan here:

SCT & Mak total dew control without heat - a solution!

The first pic below shows the insulating wrap I made from an old yoga mat for an SCT. The second pic shows a naked 7" Mak, then the same Mak with its wrap made from Coreflute. The last pics show the small 40mm fan installed into the side of the dewshield end of the wrap.

Alex.
Thanks Alex.
Getting 400X straight away is very impressive indeed.
A bit problematic with the tube rings on my MAK, but doable on my SCT.

I tend to just put the MAK or SCT in my carport hours before using it in early hours of the evening - then having dinner, watching news and current affairs - before finally getting around to viewing many hours later (or cursing because it's gone cloudy in the meantime.)

Cheers,
Renato
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Old 14-10-2020, 08:31 AM
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mental4astro (Alexander)
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Renato,

Not difficult to insulate a scope with tube rings. The wrap can be made in sections with Velcro to attach each piece around the OTA. Wavytone does this with his 10" Mak. The pic below shows his Mak as he was setting it up. He keeps the middle section of the insulating wrap on the scope, and then pops on the two other sections. Takes all of 30 seconds to attach the two other parts.

It's not just the elimination of the cooling period, it also extends the dew-free period for the corrector. How long though depends on the prevailing conditions of any given night. For me often I have no dew issues with the Mak, and the small fan takes care of things when dew starts to form. With an SCT, because the corrector is so thin the insulation won't totally prevent it from dewing up, but markedly extends how long it stays dry.

Alex.
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Old 15-10-2020, 05:15 AM
Renato1 (Renato)
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Quote:
Originally Posted by mental4astro View Post
Renato,

Not difficult to insulate a scope with tube rings. The wrap can be made in sections with Velcro to attach each piece around the OTA. Wavytone does this with his 10" Mak. The pic below shows his Mak as he was setting it up. He keeps the middle section of the insulating wrap on the scope, and then pops on the two other sections. Takes all of 30 seconds to attach the two other parts.

It's not just the elimination of the cooling period, it also extends the dew-free period for the corrector. How long though depends on the prevailing conditions of any given night. For me often I have no dew issues with the Mak, and the small fan takes care of things when dew starts to form. With an SCT, because the corrector is so thin the insulation won't totally prevent it from dewing up, but markedly extends how long it stays dry.

Alex.
Thanks Alex,
My tube rings are closer together than in the 10"Mak, which would make it more fiddly. But on the other hand, I do have a 5" MAK without tube rings, where insulation could be applied more easily.

I keep wondering if the OP ever got a decent view of Mars.
I hope our digression on his thread hasn't annoyed him.
Regards,
Renato
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