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Is it normal to get glare from Jupiter?


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4 minutes ago, stafford_stargazer said:

Viewing Jupiter I get some glare from around the planet when visually viewing.

Is this normal or are my eyepeices rubbish?

Thanks Gary 

Which scope are you using Gary? A reflector will show wide diffraction spikes coming off Jupiter. A slightly dewed up objective or eyepiece can also result in glare around the planet.

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1 minute ago, Stu said:

Which scope are you using Gary? A reflector will show wide diffraction spikes coming off Jupiter. A slightly dewed up objective or eyepiece can also result in glare around the planet.

RVO horizon 72 ED f6  FPL53.

My eyepeices are baader 6mm and tmb 3.2mm.

I think it may be quality of those but not sure.

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11 minutes ago, stafford_stargazer said:

RVO horizon 72 ED f6  FPL53.

My eyepeices are baader 6mm and tmb 3.2mm.

I think it may be quality of those but not sure.

Shouldn’t be too much issue with any of that. Hazy sky can do it too. Don’t worry about your kit, I think it sounds fine. Don’t know much about the TMB, but the Baader should perfectly fine.

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1 hour ago, stafford_stargazer said:

Viewing Jupiter I get some glare from around the planet when visually viewing.

Is this normal or are my eyepeices rubbish?

Thanks Gary 

If its red and blue glare either side of the planet’s edges then it will be atmospheric dispersion. Lower altitudes and bright planets will normally lead to such.

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1 hour ago, IB20 said:

If its red and blue glare either side of the planet’s edges then it will be atmospheric dispersion. Lower altitudes and bright planets will normally lead to such.

No it's a like reflection internally glare, white ish . Thanks 👍

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If it's a diffuse, symmetrical and stationary glow around the planet, it's likely scattered light. Quite what's causing it isn't always easy to tell. The level of polish and quality of eyepiece coatings make a difference, and bright objects are the most challenging. If your Baader 6mm is the BCO, then my experience is that it is sharp, but gives more scatter than, for example, the 10mm BCO. I've not used TMBs, but I have read that there are several makes of the same TMB design, of varying quality. And it might not be down to the optical surfaces at all; moisture in the atmosphere can cause the same effect, as can very small amounts of dew that are not obvious. Try different eyepieces over multiple evenings and look for differences.

There's some discussion here:

https://www.cloudynights.com/topic/569554-reflections-ghosting-glare-scatter-eofb/

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1 hour ago, stafford_stargazer said:

No it's a like reflection internally glare, white ish . Thanks 👍

I had a Celestron Luminos that would ghost Jupiter and cause strange glare at times, but I highly doubt the 6mm BCO would be the issue. I also had a very bad diagonal one time that caused massive scatter- rare but it happens. You could try going " straight through" if you have a means to reach focus.

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3 hours ago, Stu said:

A reflector will show wide diffraction spikes coming off Jupiter.

With Newtonians, I've had a 4.5", 8", two 10" and a 12" and none of them have shown diffraction spikes coming off Jupiter.

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1 hour ago, jetstream said:

I had a Celestron Luminos that would ghost Jupiter and cause strange glare at times, but I highly doubt the 6mm BCO would be the issue. I also had a very bad diagonal one time that caused massive scatter- rare but it happens. You could try going " straight through" if you have a means to reach focus.

Thanks.

I tried straight through but couldn't achieve focus, the diagonal is brand new yesterday William optics Di-electric.. but this also happens on my mak with different diagonal.

👍

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9 hours ago, Mr Spock said:

With Newtonians, I've had a 4.5", 8", two 10" and a 12" and none of them have shown diffraction spikes coming off Jupiter.

I don’t understand that Michael, as all the reflectors I’ve had do. Orion Optics 8” f8, 2 x 10” f6.3, 12” f6 and f5.3 all 1/10th wave or better optics. The two Heritage did too (130 and 150P); the 130 showing a double spike from its single stalk, and the 150 six spikes from the three vanes.

It’s just physics, not something you can avoid so any newt/dob will show them. They show as broad blades of light the width of the planet (or Moon), rather than spikes as such. The 8” Portaball I had was the only one which didn’t, but it had three curved supports so showed a general smearing of diffraction around the planets rather than spikes.

Perhaps you have a built-in Vulcan filter which makes them invisible for you? The scopes will be showing them, that’s for sure.

Some discussion here.

https://www.cloudynights.com/topic/532731-do-you-see-secondary-mirror-diffraction-spikes-on-jupiter/

 

 

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11 minutes ago, Mr Spock said:

All I see is a clean disc.

Well that’s great news for you Michael. Physically it is impossible for there to be no diffraction, as any scope with vanes will generate them. Obviously your eye just isn’t sensitive to them. I assume you see them on brighter stars?

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On 14/02/2023 at 23:07, Mr Spock said:

With Newtonians, I've had a 4.5", 8", two 10" and a 12" and none of them have shown diffraction spikes coming off Jupiter.

I forgot about this, but I get some farily pronounced diffraction spikes on Jupiter with my 130PDS.  Is that likely to be something to do with my eyepiece selection or could it be my spider isn't quite straight with the tube?

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You can imagine Jupiter as an aggregation of bright stars all bunched together to form a bright circle. Each of those quasi-stars will produce its own diffraction spikes. When bunched together, they form not so much a set of diffraction “spikes” off Jupiter, more of a set of wide (the width of the planet) “stripes” streaming off at right angles (if you have 4 vanes). Very pronounced every time I’ve used a newt to observe the planet.

Cheers, Magnus

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6 hours ago, Ratlet said:

I forgot about this, but I get some farily pronounced diffraction spikes on Jupiter with my 130PDS.  Is that likely to be something to do with my eyepiece selection or could it be my spider isn't quite straight with the tube?

Nope, it’s just a fact of life with Newts.

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What the OP is seeing may just be the result of slight fogging or dewing of the eyepiece eye lens. Big problem in winter…. The eyepiece can mist up when you put your warm face next to the cold glass, or maybe breathe on it slightly. Also if it’s left in the scope or in a case for a while pointing upwards it will start to dew up.

When there is even a tiny accumulation of moisture on the eyelens you will get a  glow around bright objects. 

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6 hours ago, Ratlet said:

I forgot about this, but I get some farily pronounced diffraction spikes on Jupiter with my 130PDS.  Is that likely to be something to do with my eyepiece selection or could it be my spider isn't quite straight with the tube?

Yeah same for me in my newts with 4 vanes. At low mags the spikes are obvious but the higher you push the mag the dimmer the spikes get 

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Cheers lads, I understand the concept I was more wondering about Mr Spock not getting them on Jupiter with his wider array of newts.  I assumed it was normal to get them but if he's not it made me question if I have an issue.

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On 15/02/2023 at 01:31, Stu said:

The 8” Portaball I had was the only one which didn’t, but it had three curved supports so showed a general smearing of diffraction around the planets rather than spikes.

Exactly correct Stu, many have played with different sec supports and the curved ones smear the diffraction but thats it. Glad you brought this fact of life to our attention ie diffraction spikes and newts go together, thanks Stu, Gerry

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4 hours ago, Ratlet said:

Cheers lads, I understand the concept I was more wondering about Mr Spock not getting them on Jupiter with his wider array of newts.  I assumed it was normal to get them but if he's not it made me question if I have an issue.

I have never seen spikes on Jupiter either with my 8” dobsonian nor with my new 12”. All I can see is a clear round disc. If the seeing is really poor I sometimes see a slight ghostly halo.

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6 hours ago, bosun21 said:

I have never seen spikes on Jupiter either with my 8” dobsonian nor with my new 12”. All I can see is a clear round disc. If the seeing is really poor I sometimes see a slight ghostly halo.

Have a look at lower powers and see what you see. It seems like it may be an eye sensitivity thing. In terms of physics they are there, but it seems some see them, some don’t. I don’t believe it is the scope making the difference (assuming standard 3 or 4 vane spiders)

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