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Jupiter with C11 + 127Mak SPC 7th Oct


AztecastroMcJ

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Got my first look and captures of Jupiter this season last weekend,

Last image with C11 was back end April and not used 127 Mak since July last year,

so long overdue,

seeing wasn't at its best tho may have improved by end of night say 6- 7/10 at best

1st 2 pics are same only different size taken with C11 + SPC using 2.5x barlow + ext,

this was best of around 8 avi's taken between 1am - 3am, more details see pic

The C11 was dewing and frosting as night went on so images got worse,

so between 3am - 6am i tested out few captures with new mono i-nova cam i purchased recently (still lots to buy and figure out)

for few reasons, i thought i'd try couple of captures with 127Mak + SPC,

1st (3rd pic) was using x3 tal barlow

2nd was with 2.5x revelation barlow

i then 1.5x drizzled 2nd pic, and then reduced slighty for last overcooked version

was using craterlet for capture and as!2 for align, stacking,

reg 6 for wavelets then gimp to finish

more details on pics

hopefully get few more chances before opposition and post up

p.s.anybody have or used the i - nova cams before ?

James

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post-4203-0-63704200-1350403450_thumb.jp

post-4203-0-42059800-1350403489_thumb.jp

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yeh thanks i agree, its just normal Mak not mak newt btw

was quite surprised with Mak's results as avi and live feed wasn't very good also was only 100sec capture @20fps

hopefully get C11 sorted needs another collimation and few tweaks,

and on good night it will beat the Mak

cheers

James

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I prefer the Mak images too. They look very clean.

You seem to be getting a rind artefact on some of the images, similar to that which often happens with Mars. I've noticed it with some of mine, too. I'm wondering if it's an issue with AS!2 because I'm sure I've not noticed it with Registax.

I'd also be tempted to drop down to 10fps. In theory the shorter exposures you'll get at 20fps should give a better image, but the SPC is compressing data quite heavily at 20fps and you're going to lose detail as a result. There's still some compression at 10fps, but it's nowhere near as much.

James

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I prefer the Mak images too. They look very clean.

You seem to be getting a rind artefact on some of the images, similar to that which often happens with Mars. I've noticed it with some of mine, too. I'm wondering if it's an issue with AS!2 because I'm sure I've not noticed it with Registax.

I'd also be tempted to drop down to 10fps. In theory the shorter exposures you'll get at 20fps should give a better image, but the SPC is compressing data quite heavily at 20fps and you're going to lose detail as a result. There's still some compression at 10fps, but it's nowhere near as much.

James

hey James, thx for comments

hadn't noticed rind inside planet,but can see now on 2nd pic ? is that the one u meant ?

def think my collimation is out on C11, so maybe that could be cause of rind on 2nd pic

there are some slight rings around planet that i normally remove by blackening out, cause of this i think is wavelets in reg6

i understand re more compression at 20fps but have done a few tests in past where 20fps was def better result

makes focusing easier aswell so worth doing while focussing imho

both live feeds on laptop were dissapointing so i was surprised with Maks result as seeing could have been better,

i would normally use 3x barlow and ext but after using x3 i swapped to 2.5x to try get more detail so seeing was def off

James

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Hi James With a scope as good as the C11 i would be tempted to get a better camera Seeing issues aside. It looks quite Noisy. I wouldnt trust the 20 fps setting on the spc 900 at all. Especially with the C11 at f30, it does look noisy.

Not sure if your handy at RGB imaging. If not a DBK might be a improvement though i know some are having issues with noise on those.Stuart does well with hes DFK. Then theres the flea 3. the dbk would be the easiest choice. The resason i say all this is, you have a 2 grand scope, and good as the spc is, a cheap camera working with quite a bit of noise.

Personally i would try a dbk at 30 fps imaging with the C11 at focal lengths that would likely tighten and sharpen things up a bit.

I would start at F20 to get tight sharp noise free images, shooting at 30 fps for 3 mins. And build from there once those images were showing signs of real quality.

It doesnt seem right to me that your Mak shots are looking as good or better than your C11 shots. We all have bad seeing. But even my bad seeing shots will not go down too far the quality ladder. The Mak shots look fair for poor seeing. The C11 doesnt seem to be doing very well. It looks quite blurry with heavy sharpening. Heavy sharpening will never bring the quality back. it will infact highlight the problem.

Was it cooled properly and in perfect collimation ? It seems to me theres a few issues going on that is stopping ultimate quality. One of them is the camera. But its more complicated than that, Stuart has shown results with a spc 900 similar to hes DFK. Which is why i am asking those other questions. something is not ringing true here. I am just not sure what it is. Possibly the camera isnt doing too well. The seeing is poor. and for what ever reason the C11 isnt singing. Try not to see my comments as critiscm James. My desire is to tell you how i see it. with no candy coated comments. With an eye on you getting the kind of images i am sure your skill and equipment deserves. Ive seen C11s not perform before. I once had a bad one. where the primary was slipping badly. It produced nothing but blurry images, It was a joy to go back to my Newtonian. If your sure the C11 has no problems. Then i would work on cooldown issues ( you can get fans for C11s ) collimate to a point where you can film a star and see nice concentric circles. infact if you do this and post up the images we could tell a lot from that likely. I hope im helping and not frustrating. Sometimes we have to have some frustration to improve our work though. If that interests you. Planetary imaging done well isnt easy. Or everyone would have images that shone. But its also true, that there is no real secret, its just a set of circumstances that all have to come together to create a whole. When theres weak links it hurts the images

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Good point about imaging an out of focus star. I did it with my 127 Mak after I'd rebuilt it and collimated it:

diff-rings2.png

I think it can be better, but I don't think I can get it better without an artificial star so I decided I could be happy with it for the time being. If the collimation is out it should be fairly obvious and if it's not then you can have the confidence to go looking elsewhere for problems.

James

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Good point about imaging an out of focus star. I did it with my 127 Mak after I'd rebuilt it and collimated it:

diff-rings2.png

I think it can be better, but I don't think I can get it better without an artificial star so I decided I could be happy with it for the time being. If the collimation is out it should be fairly obvious and if it's not then you can have the confidence to go looking elsewhere for problems.

James

Is that the mak or C11 ? It looks textbook perfect. Be careful when you do these tests though. Did you use a barlow ? prime focus will make everything look better than it is. If you used a barlow. Then whatever scope that is, looks spot on.

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hey James, thx for comments

hadn't noticed rind inside planet,but can see now on 2nd pic ? is that the one u meant ?

def think my collimation is out on C11, so maybe that could be cause of rind on 2nd pic

there are some slight rings around planet that i normally remove by blackening out, cause of this i think is wavelets in reg6

i understand re more compression at 20fps but have done a few tests in past where 20fps was def better result

makes focusing easier aswell so worth doing while focussing imho

both live feeds on laptop were dissapointing so i was surprised with Maks result as seeing could have been better,

i would normally use 3x barlow and ext but after using x3 i swapped to 2.5x to try get more detail so seeing was def off

I can see the rind on all the images to be honest. I can see it on all the images I posted yesterday, too. I don't think it's a data quality thing, but it's quite odd. I've not noticed it in previous years, but my images are better and I'm being more critical now. I might have to have a scan through everyone's postings to see if it crops up regularly. You may well be right that it's some sort of wavelets artefact

I'm genuinely surprised that you feel the 20 fps rate gives better images than 10 fps to be honest. I picked apart the Linux driver code for the Philips cameras earlier this year and found that at 640x480 only 5 fps is not compressed. My recollection is that the camera has an adaptive compression algorithm that varies depending on the frame rate and the bandwidth available on the USB bus, but even at the highest possible speed allowed for USB v1.1 it has to start compressing data at 10 fps and throwing some away. At 20 fps it's got to be throwing away a lot of data to be able to keep up the frame rate.

James

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Is that the mak or C11 ? It looks textbook perfect. Be careful when you do these tests though. Did you use a barlow ? prime focus will make everything look better than it is. If you used a barlow. Then whatever scope that is, looks spot on.

That's my 127 Mak. It's the other James that has the C11 :) I can't recall if I used a barlow or not at the time. It's easy enough to repeat though.

James

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there are some slight rings around planet that i normally remove by blackening out, cause of this i think is wavelets in reg6

Just coming back to this for a moment, I think it might be a gain issue. I've noticed that in some circumstances the raw images can have a small amount of "noise" around the edges of the target where the image has "spilled out" a bit. It's hard to describe the effect. You end up with a few pixels outside the edge of the target that are lit up when they shouldn't be. Not enough to soften the edge necessarily and perhaps only visible if you give the histogram a fairly hefty yank in the right direction. Sometimes the stacking process turns those into a slight "halo" that wavelets then make into a faint ring. In my experience it seems to become more noticeable as the gain goes up.

James

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Just coming back to this for a moment, I think it might be a gain issue. I've noticed that in some circumstances the raw images can have a small amount of "noise" around the edges of the target where the image has "spilled out" a bit. It's hard to describe the effect. You end up with a few pixels outside the edge of the target that are lit up when they shouldn't be. Not enough to soften the edge necessarily and perhaps only visible if you give the histogram a fairly hefty yank in the right direction. Sometimes the stacking process turns those into a slight "halo" that wavelets then make into a faint ring. In my experience it seems to become more noticeable as the gain goes up.

James

Yes sorry you posting on this thread. with the same name confused me for a sec there ( its easy done old age ) I am not sure but i think the effect you are seeing is two things. one it can be slight leans in collimation. Two the seeing does indeed pull away from the planet in moments. which gets stacked as a white ring. Infact ive thought of another issue. call this three. focussing not tight on the planet edge can also produce similar. These are the main reasons i think we get this. i get it all the time.

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I thought about using an artificial star since my seeing conditions are never really good enough to collimate on an actual star but you still need to put these things some 60m away from the scope???

And I just don't of the space or line of sign to be able to do it... are well!!!

Hence, I'm just now experimenting with Metaguide which performs some stacking / averaging of the stars centroid (or peak) to allow collimation? I'm just a beginner with this method also looking for further advise but it does seem to work, sort of???

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Good to see you back imaging James!

I'm sure the C11 images are affected by seeing/collimation/dew or cooling issues. Personally I would stick to 10fps and take a 3-4 min avi. The seeing probably improved more than you realised when using the 127 as the smaller aperture would not show up the improved conditions as much.

As Neil mentioned I took Jupiter shots with the spc almost as good as the DFK and just look what Jason (eyepod) captured with the spc and his 8" Dob last month :

http://stargazerslounge.com/topic/160929-jupiter-4th-sept-excellent-seeing-200p-auto-dob-spc900/page__hl__+eyepod#entry1626704

I'm sure with good collimation and seeing you will produce some excellent results.

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Thanks again for comments and tips everyone,

Neil i bought mono i-nova pla mx 618 cam few months ago 2nd hand for £240, took 1 AVI and 2 SER files last time out as quick practice

frame rates didn't seem quite right but dont think my ms/exposure was set right, was still very impressed with it though,

got 30fps with1/30ms exp in ROI 400x400 got 55fps and bin x2 320x240 got 100fps

will practise and read manual some more with it before next use hopefully,and sensor had lots dust marks so will need to clean carefully aswell

so i now need filter wheel and filters aswell as new focusser and dew strap heater for my dew shield

think i order 742 IR (or red filter) this week with dew strap

then add focuser, then add filter wheel and rgb filters

dont think i can buy it all this month so maybe have to wait for filter wheel and other filters

trying to cut cost as much as possible so would u buy ir742 or just red, do you use ir742 much on jupiter ?

could prob afford cheaper baader filters but would prefer to get astronomik, what you think ?

ok so managed to get out last night

so just going to post up result with star test which doesnt look good to my eyes,

i noticed it was out last time which is why i thought i'd try Mak

but find collimation dificult with dew forming on corrector so hopefully try sort next time out,

i know i should be using better camera aswell,

but have seen some great results with 8" Dob + C8+spc so i realise i should be getting much better

cheers Stuart, gud to be back, your getting some great results aswell, i noticed, fancy collimating my C11 for me :grin:

yeh i noticed metaguide thing before on 'net maybe worth downloading and trying aswell thanks

James

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Thanks again for comments and tips everyone,

Neil i bought mono i-nova pla mx 618 cam few months ago 2nd hand for £240, took 1 AVI and 2 SER files last time out as quick practice

frame rates didn't seem quite right but dont think my ms/exposure was set right, was still very impressed with it though,

got 30fps with1/30ms exp in ROI 400x400 got 55fps and bin x2 320x240 got 100fps

will practise and read manual some more with it before next use hopefully,and sensor had lots dust marks so will need to clean carefully aswell

so i now need filter wheel and filters aswell as new focusser and dew strap heater for my dew shield

think i order 742 IR (or red filter) this week with dew strap

then add focuser, then add filter wheel and rgb filters

dont think i can buy it all this month so maybe have to wait for filter wheel and other filters

trying to cut cost as much as possible so would u buy ir742 or just red, do you use ir742 much on jupiter ?

could prob afford cheaper baader filters but would prefer to get astronomik, what you think ?

ok so managed to get out last night

so just going to post up result with star test which doesnt look good to my eyes,

i noticed it was out last time which is why i thought i'd try Mak

but find collimation dificult with dew forming on corrector so hopefully try sort next time out,

i know i should be using better camera aswell,

but have seen some great results with 8" Dob + C8+spc so i realise i should be getting much better

cheers Stuart, gud to be back, your getting some great results aswell, i noticed, fancy collimating my C11 for me :grin:

yeh i noticed metaguide thing before on 'net maybe worth downloading and trying aswell thanks

James

Hi James your thinking in the right direction. Getting that camera is a good step. Its a great ccd chip. My advice on that one is learn to get the best out of it. I would suggest 100 fps might be overkill on a 11" scope. I am not sure because i only have a 9.75 " scope but i find 60 fps is max at the focal lengths i want to work at. low Focal lengths might well be usable at those frame rates ( at 1/100th secs exposure ) which is what you will be at 100 FPS but who wants tiny jupiters at fast frame rates. Not us. so getting 100fps to work well, will likely mean very high gain ( bad idea as it creates noise and dim histograms making the noise even worse )

I would suggest working at 60fps red and green possibly 30fps blue. which is what i am doing. But under good seeing sometimes 30 fps can produce nicer richer and noise free images. So i would be experimenting with those settings in mind. for very smooth rich detailed and healthy ( by healthy i mean good histogram levels ) shots. As far as IR 742 Filters go heres what i think. Its handy to have. it will certainly puil more detail out for sure, and it can be part of the colour mix shot. Like some are doing. But personally i prefer straight RGB work. Its a pure colour consideration. IR will affect the way the colour and balance is percieved to a degree. I think for the most part DP also prefers straight RGB work. So as mentioned its handy to have, it will produce more detail. it will cut through poor seeing better. in a colour mix, it will affect the balance somewhat.

As for cheap filters i am not really sure. But if you want to up your game cutting corners might not always be a best choice. If your going to be doing RGB work then good filters will put you on a good footing. I got my Astronomiks seconhand. And they are excellent Filters. I have not tried others to comment on. Baarder make some. You may want to talk to others about good cheaper alternatives. But parfocal is a must, as continually adjusting all three channel focus. will really slow you down. With telescopes that have a large focussing tolerance. Mine seems to tolerate the slight difference between red and green, and the blue quite well. I find i dont really have to adjust the blue focus. I find if i am in focus on red. blue seems quite close. But faster scopes ( faster than f6.3 ) or different designs ( scts ) may react rather differently. and you might have to tweak blue focus compared to red and green. Even though the Astronomiks are all parfocal. You should post up a star test using a 2 and 3 x barlow if you have them. And check both sides of focus it will tell you more. I hope this info is helping. You could use a COOL blow dryer ( warm at the most ) or heater bands when collimating to get that sorted maybe. Lets not forget cooldown. you can get SCT fans. and personally if i was you i would be doing that no question.

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great thx again Neil, i'll be happy sticking to 30fps and 55fps, once collimation sorted ofcourse

so list is now to buy asap

1.dew heater strip and red astronomik filter

2.focusser

3.filter wheel and G,B astronomik filters,

prob need clear filter aswell i guess to keep dust off ?

i have been putting C11 out at least 3 hrs before use so cooldown shouldn't be far off, cold air blower would be handy next year mayb ?

thanks again

James

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