Improved planet view

[10-7]

I could use some advise on how to improve my planet viewing my scope is a 10" dob , 1250 mm focal length. I have a 30mm, 17 mm and a 9mm eyepieces and a 2.5x Barlow. I was hoping  for a larger visual and a little more detail. I am such a rookie and accept all advise 

 

thanks Ken

Edited September 8, 2020 by 10-7
Missing lettr

[CraigT82]

The 17mm eyepiece with the 2.5x barlow will give you 183x magnification which is a really nice place to be for planetary viewing.

Is the scope collimated? And is it allowed to cool down before observing (if taken out from indoors)? 

Sometimes you're first views can be underwhelming but that could just be poor seeing (assuming scope is collimated and cooled), once you get a night of good seeing you'll really see what the scope can do and the image will be beautifully sharp and steady... got to get out there often enough to catch that good seeing!

[vlaiv]

Get sharp eyepiece at about 5-6mm mark.

Most nights you want to be around x200 with ability to go to x250 or even x300 on the best nights, so you should have suitable eyepiece.

If your x2.5 barlow is GSO tripled triplet lens barlow - it is closer to x2.2 magnification and that will give you about 7.7mm from 17mm eyepiece - not entirely unusable but very close to 9mm that you have.

Here is the list of things to watch out for:

1. Make sure your scope has reached ambient temperature - this means leaving it outside at least one hour prior to observing. Uncap the scope and point it slightly towards the sky to let hot trapped air escape the OTA. 10" is a large mirror and it might not reach thermal equilibrium on nights when it gets cold quickly - so watch out the forecast for those nights that don't have large temperature drops

2. Place your scope on the grass - not on pavement or concrete or anything that might soak up the heat during the day.

3. Make sure you are not observing in direction of houses, large bodies of water, roads - anything that will soak up heat during the day and then radiate it back creating turbulent air. Best is grass and parks / forests.

4. Keep an eye on jet stream and seeing forecasts:

https://www.netweather.tv/charts-and-data/global-jetstream#2020/09/08/1200Z/jetstream/surface/level/overlay=jetstream/orthographic=-6.72,57.59,712

and

https://www.meteoblue.com/en/weather/outdoorsports/seeing/michigan_united-states-of-america_5060420

5. Don't get fully dark adapted for planets - keep a light on next to you so you don't get fully dark adapted. Dark adaptation is good for observing objects of deep sky but not good for planets as you loose ability to resolve and your color perception is lowered - both help see details on planets

6. Wait until targets are highest in the sky - then you observe thru the least of atmosphere. Wait until target is close to opposition - Jupiter and Saturn are now past opposition so they are getting smaller, but Mars is nearing opposition - it will be particularly interesting around first week of October

7. Sometimes seeing is good right after sunset - see if you can observe your target then. This is most useful for the Moon, but sometimes one can have very good images of Jupiter this way as well

Edited September 8, 2020 by vlaiv

[Starwatcher2001]

Currently Jupiter and Saturn are not very well placed in the sky for good viewing. The inclination of their orbit places them quite low in the sky for those in the Northern hemisphere. Therefore you're looking at them through a lot of atmosphere which spoils the view somewhat. As you might gather, the general state of the atmosphere can affect the view as well - often termed "seeing".  If you observe the same object for a while, there may be periods when the atmosphere settles down for a short while and the image will suddenly improve. One night can be glorious and the next poor.  On nights that seem poor it's worth looking for different targets like double stars, especially towards the zenith where the atmosphere is thinner.

What you'll also find is that the more experienced you become with observing objects, the more you'll see - "getting your eye in", if you will. Some people find sketching what they see sharpens their observing skills and helps them see more. I find that describing the detail into a voice recorder helps me.

Something else that will help is sitting down to observe. It's a lot more comfortable, helps you keep your head in just the right spot, and encourages you to linger longer on each object. I also understand it helps put less strain on the visual system.

Finally, if you can avoid observing objects directly over houses or other concrete buildings, it helps. Buildings are prone to obsorbing heat during the day, which they radiate out at night disturbing the air - kinda like looking over a camp fire.

[John]

Currently there are a lot of issues conspiring against getting good views of the planets because they lie low in the sky from the UK and these are not really related to the scope.

With Jupiter I'm finding that 100x - 150x is delivering the crispest views and sometimes even those are not that sharp. With Saturn and Mars you can push things on to 200x or perhaps a bit more (Mars being higher in the sky helps).

I have to say that my smaller aperture refractors are making a better job of handling the adverse positioning of the planets than my 12 inch dobsonian is.

 

[Starwatcher2001]

 

Quote

5. Don't get fully dark adapted for planets - keep a light on next to you so you don't get fully dark adapted. Dark adaptation is good for observing objects of deep sky but not good for planets as you loose ability to resolve and your color perception is lowered - both help see details on planets

That's a good tip Vlaiv, I've never come across that before. Thanks.

[John]

Some of my best views of the planets have come when observing them against a sky which still had quite a lot of light in it. Dark adaptation is just not needed and actually hinders seeing the more subtle detail.

 

[Pixies]

Yes - deffo agree with the dark adaption tip. The last time I was observing Mars, it was hard not too, since the moon was so bright. I actually had the kitchen lights on.

@10-7 it's worth persevering with Mars just now. It's approaching opposition in a few weeks and won't be this large in the sky for 15 years! I have just been learning good planetary viewing practise, and it takes some effort, but totally worth it.

Here are some general tips:

Here's my recent observation report:

 

 

Lots of tips in the Observing - Planetary section

[dweller25]

In addition to the good tips above I would suggest buying a neutral density 96-03 (50% transmission) filter to dim the views a little. A 10” Newt catches a lot of light and can wash detail away on the planets.

[johninderby]

A filter is a good idea but prefer a variable polarising filter. Really helps on  Venus as well.

https://www.firstlightoptics.com/moon-neutral-density-filters/astro-essentials-variable-polarising-moon-filter.html

 

Edited September 8, 2020 by johninderby

[AstroTim]

I tried a neodymium moon and sky glow filter on Mars a couple of nights ago, when the moon was particularly bright and close by, and it seemed to improve the amount of detail visible, more so than when I’ve previously tried it on Jupiter. It seemed to cut down some of the reflection/glare around the perimeter of the planet, making the polar cap stand out more clearly, as well as a little more surface colouration. It also improved the views of the Moon by removing a bit of the glare and allowing the features to stand out (possibly the best view of the Mons Hadley area I’ve had to date). I don’t know how the improvements compare to those using a neutral density filter as mentioned above, but if you have a neodymium filter it might be worth giving it a try.

Tim

[Stardaze]

20 hours ago, johninderby said:

A filter is a good idea but prefer a variable polarising filter. Really helps on  Venus as well.

https://www.firstlightoptics.com/moon-neutral-density-filters/astro-essentials-variable-polarising-moon-filter.html

 

I can relate to these on a camera lens John, you have to twist them to obtain the best polarisation. How would that work on an eye piece? Would you need to twist it, reseat, and keep doing so until the optimum level is achieved? Have you the 1.25" version? I have been toying with something to reduce the moons glare, whilst also thinking about the something for planetary, seems a good starter.

Edited September 9, 2020 by Stardaze

[johninderby]

Just putting the variable filter on the eyepiece nosepiece is the easiest way. Then just pull out the eyepiece and rotate the filter. Usually only takes two or three times to get it adjusted right. 

Another way is to use two single polarising filters. One on the eyepiece and one on the 1.25” to 2 adapter. Then simply rotate the eyepiece to adjust. I have a 2” variable polarising filter which I removed one of filter elements to make it into a single filter. I already had a single 1.25” filter that I use with my solar wedge.. 🙂

For some reason single filters aren’t cheap and many of the variable filters can't be seperated into two singles. .

Edited September 9, 2020 by johninderby

[Stardaze]

16 minutes ago, johninderby said:

Just putting the variable filter on the eyepiece nosepiece is the easiest way. Then just pull out the eyepiece and rotate the filter. Usually only takes two or three times to get it adjusted right. 

Another way is to use two single polarising filters. One on the eyepiece and one on the 1.25” to 2 adapter. Then simply rotate the eyepiece to adjust. I have a 2” variable polarising filter which I removed one of filter elements to make it into a single filter. I already had a single 1.25” filter that I use with my solar wedge.. 🙂

For some reason single filters aren’t cheap and many of the variable filters can't be seperated into two singles. .

Thanks for this. Are polarisers your go-to for planets? Do you use anything else? 

[RT65CB-SWL]

Hi @10-7 / Ken and welcome to SGL.

I am another that uses a variable polarising filter. I have 1.25" & 2".

I also use a 1.25" neodymium as well. I like to think of it as my'Swiss-Army knife' filter.

For viewing Venus and detecting the cloud detail/structure, then you can use a #47 (violet).

Edited September 9, 2020 by Philip R

[johninderby]

The Baader Neodymium filter is the one I use on all the planets.  Find the polariser does help sometimes when used as well as the neodynium. 

[johninderby]

6 minutes ago, Philip R said:

 

I also use a 1.25" neodymium as well. I like to think of it as my'Swiss-Army knife' filter.

 

He he 😁

[Stardaze]

5 minutes ago, johninderby said:

The Baader Neodymium filter is the one I use on all the planets.  Find the polariser does help sometimes when used as well as the neodynium. 

Interesting that the neodymium crops up again. Some love them, whilst others don't seem to. Might add one at the end of the month to the collection in readiness for October. Need to slow down on purchases 😂 The XW 5mm turned up today... How have you found yours?

[johninderby]

My XW 5mm hasn’t had a lot of use lately. Seems all right but wish it had a wider fov.

 

[AstroTim]

9 minutes ago, Stardaze said:

Interesting that the neodymium crops up again. Some love them, whilst others don't seem to. Might add one at the end of the month to the collection in readiness for October. Need to slow down on purchases 😂 The XW 5mm turned up today... How have you found yours?

Until a few nights back (see my post above), I had been a little disappointed with mine, as it didn’t seem to be making any difference to the views I was getting (mainly viewing Jupiter and Saturn). Maybe the seeing conditions on those other nights caused there to be little or no benefit from using the filter, or maybe you get more of a benefit on Mars than Jupiter (although I am sure I read that they are particularly good for Jupiter).

Tim

[johninderby]

I think the better the seeing conditions the better the neodynium filter works. When seeing is poor no filter is really going to help.

Edited September 9, 2020 by johninderby

[10-7]

Thanks all for the advice ! I learned a few things. Unfortunately it's been crap seeing for the past 3 day and it's going to continue until Monday here I mid michigan