Mars just a white disc - can I improve the image?

[piers007]

Hi Guys and Gals, I own an Explorer 200 with EQ5 mount and dual axis drives. I also have 10mm, 25mm eyepieces and a 2x Barlow Lens.

I can get Mars into quite a nice disc in the scope but thats just it, its totally white, no contrast at all. The scope has just been bought through the post so I'm not sure if it needs collimation (I will check tonight). Is there anything I can do?

I have tried to reduce the light coming into the opening with no success and have no filters yet, suggestions appreciated.

Piers.

[themos]

pulls up a chair

[Cloudwatcher]

I can't offer an explanation for what you saw,piers,only confirm that I had a similar view of Mars last night. The planet appeared as a bright but bland,slightly oval,disc. The only 'features' discernable were a slightly darker area to the west in the North Polar region and an even fainter 'band' in the Southern hemisphere above the Pole.

CW

[barkis]

Hi. Piers. A white disc.? Are you sure you have the planet focused properly?. If I was you, I would select a bright star first, using a low power eyepiece, Then gradually build up the magnification on the star until you get to the same combination you used on mars. If the star remains as a point of light, or at least the image you get is indicative of a bright star. If that works out OK,then I am baffled. If you find when you get to the same combo you used on the planet, that the star image is bloated. then it is obviously a focus problem you have.

I can't think of another way to check.

Ron.

[hairymunky]

Thats the way I saw Mars through my 8" dob last night. Just a whitish/yellowy globe.

I just put it down to being still quite low on the east. I was expecting something

with a bit more detail, but.. will try again another night if its clear....

[chuenmanc]

Perhaps you need to check the collimation of your scope.

The night my CPC1100 arrived, I had a look at Mars and it was just a featureless white-ish disc. Last night after re-collimating with Bobs Knobs, I could make out definite surface markings. The seeing may also have been a factor, but it's worth checking your collimation. Failing that perhaps a coloured filter?

[John]

I'm feeling slightly relieved by reading this thread that others are finding Mars challenging at the moment as well. Having been into astronomy for many years I have observed Mars over the years through a variety of scopes and I have to say that this time around I'm finding it harder than ever to make out surface details - despite the fact that my Vixen ED102SS refractor is one of the best scopes optically I've ever owned.

I was wondering if it was my eyes as I'm getting older !.

At the moment through my refractor I can see Mars as a very pale orange disk with, during moments of good seeing, suggestions (no more than that TBH) of darker markings and perhaps a brighter area at one pole.

Looking back through my observing notes I have recorded seeing as much, if not a little more, detail though just a 60mm refractor - but that was years ago.

The 2007/08 approach of Mars is not a very close one compared to previous years - maybe it will be better in a few years time.

Astronomy is often about playing the "long game"

John

[The Warthog]

I haven't had much luck with Mars in the last three approaches. Usually at best I can make out the white button of the pole, and glimpses of surface detail. this year, I haven't had many clear nights since it started to get good.

[Albireo380]

I can't offer an explanation for what you saw,piers,only confirm that I had a similar view of Mars last night. The planet appeared as a bright but bland,slightly oval,disc. The only 'features' discernable were a slightly darker area to the west in the North Polar region and an even fainter 'band' in the Southern hemisphere above the Pole.

CW

I tried Mars on monday evening, with a 10" Slyliner Dob. It is well collimated (recently with a baader laser collimator). I got a very similar view to the one spoken of by CW above. I suspect that we need to wait until Mars is as high in the sky as possible before any significant detail will be seen. Of course, if Mars is experienceing a big sand storm at the moment, no real features would be seen.

Tom

[Stephen Green]

Hi Piers I all so did not get clear image and I treid my two scopes being Celstron Nextstar 6se and then my Mead LX200 10inch

Stephen

EAS East Sussex

[Zeffer]

I had a go on Monday night through the C8 and got a nice orange disc with a hint of paleness at the top but that was all. Seeing seemed very good (the Orion neb was the best I have seen it) but Mars just kept on boiling.

[Rob]

Had my first go last night at midnight with a well cooled C8. Shes very bright, and I think thats half the problem... this is also where filters come into play for scopes 8" and over. The boiling was indeed quite bad.

I could make out detail though in two areas of the disc..

[Trevor]

Piers

When I had my Ex200 for viewing the moon I used to leave the dust cap on the scope and remove the small plastic cover just leaving the small hole about 2 inches in diameter, don’t know how it will work with planets might be worth a try.

Trev.

[John]

Piers

When I had my Ex200 for viewing the moon I used to leave the dust cap on the scope and remove the small plastic cover just leaving the small hole about 2 inches in diameter, don’t know how it will work with planets might be worth a try.

Trev.

It's an idea but you will then be working with a 50mm aperture scope which will seriously compromise the resolution on the planets

John

[piers007]

Thanks guys for all you help on this one being a newcomer to the forums. I had a 10mm with 2x barlow on a Explorer 200 EQ5 and mars is still white but last night i did see a couple of features, some darkening on the disc so I'm pleased with that.

Tested my collimation and thats all fine and dandy.

Last night was great seeing though, especially at around 1am before i went to bed. I got my first look at Andromeda so I was well pleased!

For Mars I guess we will have to wait until its higher in the sky at Xmas time for a good look.

Thanks again,

Piers.

[Pauln]

I am new to this too, but I found that a filter helped. I was using a C6-N with a 6mm eyepiece and a 2x barlow at about 23:30 and then tried red, orange and blue filters and could just about see detail but not a lot.

[chuenmanc]

I tried again last night after having received some coloured filters. Orange #21 helped a little for the surface features, and blue #80A seemed to give a hint at the polar cap. However, a variable polarizing filter gave for me the most pleasing view. It cuts down on the brightness to let you see the surface features more clearly.

[Casus belli]

I believe (and I may be wrong here) that a higher focal length is better for viewing the planets. Lower focal lengths tend to need more accurate collimination. I have seen detail in Mars but I spent a lot of time looking at a featureless blob before it snapped into view for a few seconds.

[asteria]

Hi all - I tried Mars as well last night, using a f12 Maksutov, 150mm aperture. It was quite difficult to focus, especially low in the sky. However, as it rose, the view improved. I could make out dark features on the surface. This was improved with the same filter Chuenmanc used (#21 orange) and also blue (#80A). The ep was a 9mm TMB Planetary giving 200x, probably the outside limit with this scope, in typical seeing conditions.

I also got a nice widefield view with a William Optics WA 15mm, giving a good sense of Mars hanging in space!

I have to say that Mars is a pretty challenging object!

Good luck.

Ed

[The Warthog]

Everyone seems to agree that Mars is always a challenge. Last time around, I was still using a 114mm f/9 scope, and did a sketch, using the rule that if I saw any marking on the surface twice, I would include it in the sketch. I wasn't too happy with the result, but I published it on a forum, and was congratulated on getting that amount of detail! It took about a half hour of staring until my eye went twitchy.

[themos]

I am going to have bash at it tonight, the weather prediction looks good. I'll double up the Barlows (a 3x and a 2.5x) and use the shaky/dodgy EQ1 and the 114mm f/8 reflector with the ToUcam.