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Hi All,

im totally new to this and have been getting setup over the past 3 months. I’ve purchased a Skywatcher 150P on a EQ3 Pro mount. 
 

I have a 2x and 3x Barlow with 10x and 20x eyepieces. I’m trying to view and photograph Mars as it’s so bright at present and easy to see however I’m really struggling to see anything more than a bright ball when viewing and when photographing it’s just a blurry ball. 
 

I have a canon 700d DSLR with t ring and adaptors  

can folk suggest what combination of Barlow / eyepiece would be required to view Mars in all its glory and possibly lens and iso/exposure settings to get some nice shots too please. I’m aware I may need to stack and am tech savvy so this bit should be ok. I just can’t seem to get anything at present to process.

help!! 

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I don't know if my situation will apply, photographically, but I have a 150mm f/5 Newtonian myself.  During Mars last opposition, I had to use a variable-polariser, to reduce the flares from the telescope's spider-vanes, and to enable the planet's features to be seen more easily...

WJYLBRu.jpg

That's exactly how Mars appeared through my own, before and after the variable-polariser.  You do retain the resolution afforded by the 150mm aperture, but the light-gathering capability of same is not our friend when viewing the brighter of planets, at least among apertures at 150mm and somewhat smaller.  With the larger apertures, higher magnifications are possible, well over 200x, and that will dim the objects and vanes suitably in addition.

Edited by Alan64
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Hi,

If you have a 150mm/5" telescope, double the diameter of the telescope to find the most you can get out of your telescope which is 300x. Divide the focal length (it should say on your telescope or your manual) of the telescope by the number it says on your eyepiece (you have 10mm and 20mm). For Barlow lenses multiply your focal length by 2x or 3x and then divide by your eyepiece number (focal length of eyepiece). If the magnification is above 300x then you will get a blurry image.

 

 

Edited by Spacecake2
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10 minutes ago, Spacecake2 said:

I can help you if you know your telescope diameter in inch or millimetres. 😀

 

The Skywatcher 150p has a primary mirror 150mm in diameter.

With that scope I think I would be using the 10mm eyepiece with the 2x barlow to get 150x magnification. Allow the scope to cool down to outside temperature, focus carefully and give your eye time to adjust to the brightness of Mars and you will start to see darker markings and maybe the tiny south polar cap. South is at the top with the newtonian scope view.

I don't image so I can't help you there.

 

 

Edited by John
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Well, you could try the 10mm eyepiece and the x3 barlow together.

If your scope focal length is 750mm, then the magnification will be :

Mag=(750x3)/10 

Mag=(2250)/10

Mag=225

Which is a good power for Mars.

Cool the scope well before viewing.

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If I'm correct, the 150P is F5, so has a focal length of 750mm. If you divide the focal length of your scope by that of the eyepiece you're using you'll get your magnification. Eg. 750÷10 = 75X. A 2X barlow will then give you 150X and a 3X barlow 225X. Both are good powers for Mars, but your scope needs to be perfectly colimated and thermally stable. Also, the local seeing conditions need to be good with little or no turbulence.  A misty night may give better results than a truly clear night. Accurate focus needs to be maintained too, and you'll need to study the tiny disk carefully for 10 or 15 mins before all the subtle detail shows itself. Sometimes an orange filter will bring out dark markings while a light blue will show ice caps, clouds and mists.

Edited by mikeDnight
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Your scope is certainly capable of showing detail on Mars. I have a Heritage 150p which is essentially the same scope but in a collapsible tube with a plastic helical focuser.

Some weeks back I was able to see the polar cap and dark markings on the surface, powers of up to over x300 were useable but x220 ish was best.

Conditions play a large part in what you see, and I understand the Jetstream is overhead currently which can obscure the detail. The only answer here is to observe as often as possible and spend time at the eyepiece in order to pull the detail out. Make sure the scope is cooled and collimated well.

This is an iPhone shot through the scope; the views were better than this. The second one has been processed and is nearer the detail level I was seen.

CC53FE26-F38F-4AF7-8114-07FEDBBF8DB4.jpeg

69872D56-C07D-48C4-97E5-47A6260D1A50.jpeg

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Last night I used a Neutral Density (or Moon) filter on Mars, it reduced the glare just enough to enable some decent surface detail to be seen.  I haven't tried my 150P on Mars yet but I intend to before it zooms away too far, but right now the brightness will wash out some of the detail.  You could even try keeping the main end cap on the telescope and just open the small cap (if your telescope has this option), this should reduce the brightness quite a bit but higher magnifications might not be usable.  Sometimes better detail can be seen on a smaller disc, you just need to find the best balance of size vs sharpness.  You may even find that you get better visual views as Mars dims over the next few weeks, though it won't look as big in the eyepiece.

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9 hours ago, Stu said:

Your scope is certainly capable of showing detail on Mars. I have a Heritage 150p which is essentially the same scope but in a collapsible tube with a plastic helical focuser.

Some weeks back I was able to see the polar cap and dark markings on the surface, powers of up to over x300 were useable but x220 ish was best.

Conditions play a large part in what you see, and I understand the Jetstream is overhead currently which can obscure the detail. The only answer here is to observe as often as possible and spend time at the eyepiece in order to pull the detail out. Make sure the scope is cooled and collimated well.

This is an iPhone shot through the scope; the views were better than this. The second one has been processed and is nearer the detail level I was seen.

CC53FE26-F38F-4AF7-8114-07FEDBBF8DB4.jpeg

69872D56-C07D-48C4-97E5-47A6260D1A50.jpeg

Hi there, I assume you have just 'blown' the images up a bit here and these are not the actual sizes taken with a camera?

 

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Hi All, I'd just like to say thanks for all those that have commented.  It's a tad confusing when getting started as you'll all probably remember but the advice has been clear and easy to follow.  

It seems like I now understand regards to the usable magnification and how to calculate this given the kit I have.  If I have then I will try again tonight (weather permitting) by placing my scope outside for a couple of hours and using a 10x eyepiece with a 3x barlow as my scope has a focal length of 750mm which if my calculations are correct works out to 225x magnification?

Then on to working out how I can photograph this with the Canon 700D....

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48 minutes ago, Hoopla said:

Hi All, I'd just like to say thanks for all those that have commented.  It's a tad confusing when getting started as you'll all probably remember but the advice has been clear and easy to follow.  

It seems like I now understand regards to the usable magnification and how to calculate this given the kit I have.  If I have then I will try again tonight (weather permitting) by placing my scope outside for a couple of hours and using a 10x eyepiece with a 3x barlow as my scope has a focal length of 750mm which if my calculations are correct works out to 225x magnification?

Then on to working out how I can photograph this with the Canon 700D....

Hi,

The numbers on the eyepieces are their focal lengths in mm so it is 10mm rather than 10x. To get the magnification that a certain eyepiece gives you divide the focal length of the telescope (750mm in your case) by the eyepiece focal length so using a 10mm eyepiece gives you 75x in your scope. Using a 2x barlow doubles the effective focal length of the scope so you then get 150x when using the 10mm eyepiece with the 2x barlow lens. If you use a 3x barlow then it's 225x as you have worked out.

Maximum useful magnification depends on lots of factors including the size and optical quality of the primary mirror or objective lens in the scope, the seeing conditions on that occasion (the main factor really) the state of cooling and collimation of the optics in the scope scope and the target being observed.

In reality much of the observing through telescopes is done at low or medium magnifications so using very high magnifications is not really the be all and end all. On the planets and double stars and often the moon, higher magnifications (say 130x - 250x with your scope) are very useful but for galaxies, clusters and nebulae low to medium magnifications (say 30x - 100x with your scope) are often much more effective.

In theory a 150mm aperture scope should have a maximum useful magnification of 300x or so but that assumes that all the many factors involved come together perfectly and that the target object is suitable. This is only very rarely the case which is why the highest useful magnifications are usually quite a bit lower than the theoretical maximum.

Hope that helps a bit :smiley:

 

Edited by John
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Imaging planets is something of an art.  You can get an image with your telescope, but you need a Barlow lens to increase the image scale, and a camera capable of taking a video. A single shot is guaranteed to look distorted and blurry, because of the 'seeing'. You can try using a DSLR, but it is better to use a dedicated planetary camera, capable of taking several thousand frames of video at up to 200 frames/sec, and with a cropped region-of-interest to speed things up and save on storage. And then process the result.  With good seeing you should be able to get a decent result.  Have a look in the Planetary Imaging thread here to see what others have achieved (and with what kit).

You also need a mount that will at least track, but it seems you have that.  And a good RACI finder to re-find Mars should it wander out of shot.

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11 hours ago, Hoopla said:

Hi All, I'd just like to say thanks for all those that have commented.  It's a tad confusing when getting started as you'll all probably remember but the advice has been clear and easy to follow.  

It seems like I now understand regards to the usable magnification and how to calculate this given the kit I have.  If I have then I will try again tonight (weather permitting) by placing my scope outside for a couple of hours and using a 10x eyepiece with a 3x barlow as my scope has a focal length of 750mm which if my calculations are correct works out to 225x magnification?

Then on to working out how I can photograph this with the Canon 700D....

My 150/750 is on a manual mount, therefore maxing out the aperture is more difficult.  750mm is a bit short for a 150mm aperture.  For the higher powers, I use a 2.8x and 3x barlows with a 12mm 60° eyepiece, and for effective 4.3mm(174x) and 4mm(188x) eyepieces, respectively.  I've had great success in that.  But you also have the option of sourcing a dedicated 4mm wider-angle eyepiece, with a larger eye-lens and greater eye-relief.  Same goes for a 6mm, then to barlow that with a 2x, and for an effective 3mm(250x).   

Then, as you go up in power, the telescope, and anything else present within the light-path, must work harder to produce sharp, pleasing images.  The atmosphere plays its part in that as well.  Equipment-wise, collimation of the Newtonian must be spot-on, and the eyepieces and accessories of a quality to complement.  But the latter doesn't necessarily require "breaking the bank".  Careful consideration when purchasing the other half of a telescope(eyepieces, et al) will go a long way in ensuring a successful experience.

For it is the higher and highest powers where exclamations of "Wow!" and "Look at that!" are emitted.

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6 hours ago, Hoopla said:

thanks for the advice. I assume the EQ3 Pro can track Mars though or am I wishful thinking? 

You have the Eq3 pro Synscan? If you set it up properly, it will track Mars as well as the starry sky. All GoTo mounts will track planets once set up. The default siderial rate will track Mars. Yes, Mars does move across the sky, but not fast enough to matter in an hour or two.

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