Embarrassing Jupiters webcam clinic

[Space Cowboy]

OK, so here are my latest Jupiters. I think over processed, but I'd welcome comments on how to improve with my set-up. Captured using Sharp-Cap, seeing moderate, transparency poorish. I don't have an IR filter on my SPC880 and I hear that this can cause focussing probs. Should I get one and is there much difference if I spend a tenner or 30 quid?

Thanks in advance!

All images - Resolution=640x480; Frame Rate (fps)=5.00; Colour Space / Compression=YUY2; Brightness=52; Contrast=32; Saturation=69

First image:

Exposure=-10

Gamma=0

Gain=44

Next two:

Exposure=-8

Gamma=7

Gain=23

Next one:

Exposure=-6

Gamma=0

Gain=24

Final two:

Exposure=-8

Gamma=0

Gain=23

1 is too dark. 2 and 3 have good luminance but 2 is a little too noisy and 3 too soft so you want something in between those two. 4 is too soft, 5 is over processed and 6 is too dark.

They are all good images I'm just nit picking What scope did you use?

[x6gas]

1 is too dark. 2 and 3 have good luminance but 2 is a little too noisy and 3 too soft so you want something in between those two. 4 is too soft, 5 is over processed and 6 is too dark.

They are all good images I'm just nit picking What scope did you use?

Thanks - I know this is a 'tough love' forum which is why I posted them in here and this is exactly the kind of feedback I am looking for.

They are with my 11" Edge HD - and I am expecting much from this scope! Really want to get to the limit of what can be achieved with a webcam before upgrading to a dedicated planetary cam. Would an IR filter help do you think?

Wish I'd had longer to see if I could have captured anything at a higher frame rate... the seeing wasn't great but I am sure there was more to be had.

[Space Cowboy]

You've certainly go an outstanding scope there and with some extra focal length and an IR filter (I'm no expert on IR filters so can't say whether an expensive one is going to make much differance over a cheap one).

You need to be using 10fps or even 15fps. I did try 20fps but had bad video compression artefacts with the spc 880/900.

A 3-4 min avi will get the most out of your webcam. Ideally you want to be stacking at least 500-1000 frames.

Did you use a barlow i'm guessing not? f25-30 is where you want to be with focal length to maximise the detail.

[x6gas]

Yes, no barlow on these. I literally managed 4 captures (90 seconds and 3 x 180 seconds) before the cloud rolled in - very frustrating! I think I was stacking the best 5% of frames IIRC...

[dag123]

Hi,

Finally a break in the clouds.

Now suitable armed with a motor-drive for my scope I was able to take longer captures (upto 1000 frames). Although it was still a tad tricky to get the motor to the correct tracking speed. The slight inaccuracy of my polar alignment showed as it was the changes in declination that caused me to stop most captures.

I stil had issues with the settings, trying to match some of the settings suggested

After a lot of messing about these seemed to give the best results: brightness: 29, gam: 0, gain: 15, shutter: 1/33, fps: 10

If I increased the gain any higher the image on screen was washed out white!

If I increased the brightness any higher I seemed to loose the colour and the images looked black and white.

Please find attached two images from my first capture (about 700 frames). Both have been through Castrator to isolate the planet.

The first is the output of registax after accepting all the default settings, the second after messing about with the wavelet settings.

I am very pleased that I now seem to have colour in my images.

I have a number of other AVIs to play with and will see how I get on with those.

I was using my Celetron barlow x2 for these captures. Am I right in thinking that this changes my f5 (AstroMaster 130EQ) to f10?

I have read that a higher f-number is better for imaging, does that mean I could consider a more powerful barlow, or is that pushing the limits of my scope?

dag123

[DrRobin]

Hi Dag,

They are both very good images, looks like you have cracked the colour issue. Don't get too hung up on matching exact brightness and gain settings, it all depends on the seeing, how bright the object is and the speed (F ratio) of your set up. I would say you have got it bang on there.

Perhaps the next thing to look at is the tracking, get that right and you can then stack more frames and it allows you to fiddle with your camera settings more, without worrying about having to re-centre all of the time.

The F ratio is derived by dividing the focal length of the scope by the diameter. I am interested to see that the 130 is F5, most scope of that size are often F10. The lower the F number the faster the scope, so the less light is needed and hence the shorter exposure, that's is why you can get fast shutter speeds on the SPC.

You are correct, using a 2x barlow makes your set up F10. I am not sure that a higher F number is better for imaging, actually I would have thought it was the reverse. My old scope was F11 and I used a 2x barlow to take it to F22. My current scope is also F5 and a 3x takes it to F15, a 5x (which I find too powerfull) takes it to F25.

Some people use up to F30, but in my experience everything has to be perfect to get reasonable images.

A higher F number is usually the result of a big barlow on a long focal scope and goes hand in hand with high magnification, trying to get a big image.

If I buy a telephoto lens of 300mm focal distance at F5 for my camera it costs about £300. If I buy a 300m lens at F2.8 for the same camera, it's about 3 times as big, weighs a tonne and costs about £1500, so a lower F number is the thing to go for.

Hope this helps.

[Daz1974]

This is my 2nd ever attempt and would appreciate those who are more experienced to comment.

I have a Skywatcher 130p Goto, and used a SPC880/900 webcam with the bundled skywatcher 2x barlow. Captured using Sharpcap, and manipulated in Registax 5. I didnt record the settings used but this image was taken from a 2 minute AVI at 10fps

[superjody]

here is another attemp but still not too good, i have the equipment but cant get the quality of images that others are getting.

I live near manchester so would the orange skies not be helping??

Object_20111114_2012_571.jpg

[x6gas]

here is another attemp but still not too good, i have the equipment but cant get the quality of images that others are getting.

I live near manchester so would the orange skies not be helping??

Object_20111114_2012_571.jpg

What kit and camera settings are you using? I'm no expert but it looks to me as if the saturation is a bit over-done on this one...

[DrRobin]

Hi Superjody,

Another good image with quite a lot of detail. I don't thing light pollution makes that much difference on bright objects like Jupiter, it's so bright so as long as it's not terrible and I am guessing it isn't for you as your background is pretty black, then it probably isn't a problem.

You could try an light pollution filter, but I doubt it would make much difference.

[malc-c]

Well I had another try this evening, slightly better results, although when uploded to the forum the image has a blue tinge which isn't present on the original here.

Settings:

[Philips SPC 900NC PC Camera]

Resolution=640x480

Frame Rate (fps)=15.00

Colour Space / Compression=YUY2

Exposure=-5

Brightness=51

Contrast=35

Saturation=-11

Gamma=2

ColorEnable=255

BacklightCompensation=0

Gain=58

Best of 3000 frames capture stacked and then wavelets used to bring out the detail. Hardly any onion rings, well not as prominent, but still a work in progress

200P, with two 2x barlow stacked - approx f20

[DrRobin]

Nice one Malc,

I have had a night out and it's fairly misty/damp here so no imaging for me tonight. Nice image, great detail and colour. I am just hing for clear skies tomorrow night.

[superjody]

What kit and camera settings are you using? I'm no expert but it looks to me as if the saturation is a bit over-done on this one...

Im using a skywatcher 250 and an spc880. the settings were 10fps, about 56 gain and possibly turned up the brightness. I might have gone a bit overboard withthe colours in registax

Hi Superjody,

Another good image with quite a lot of detail. I don't thing light pollution makes that much difference on bright objects like Jupiter, it's so bright so as long as it's not terrible and I am guessing it isn't for you as your background is pretty black, then it probably isn't a problem.

You could try an light pollution filter, but I doubt it would make much difference.

thanks, Im guessing light pollution wont show as im using a fairly fast shutter speed, it shows up if i try any long exposure things

[DrRobin]

Hi,

Yes a light polution filter will be required for longer exposures. I have a Lumicon Deep Sky filter, they seem good for colour CCDs, due to the passbands at all the right frequencies, whilst blocking all of the street lights. They are moderately priced and performance is probably close to filters costing 2x as much.

The only filter I use for the planets is a cheap (Morgan) IR filter, seems to do the job.

I hope it's going to stay clear tonight.

[x6gas]

This is a great thread BTW!

[DrRobin]

Hi,

Space Cowboy started a great thread and Jupiter is such a good target. I was all set to have another imaging session with my new DFK tonight only to see the mist come over and end that idea.

Of course it's clear now, but after a couple of glasses of wine it's too late and there is cloud on the horizon.

[Space Cowboy]

Hi Dag,

They are both very good images, looks like you have cracked the colour issue. Don't get too hung up on matching exact brightness and gain settings, it all depends on the seeing, how bright the object is and the speed (F ratio) of your set up. I would say you have got it bang on there.

Perhaps the next thing to look at is the tracking, get that right and you can then stack more frames and it allows you to fiddle with your camera settings more, without worrying about having to re-centre all of the time.

The F ratio is derived by dividing the focal length of the scope by the diameter. I am interested to see that the 130 is F5, most scope of that size are often F10. The lower the F number the faster the scope, so the less light is needed and hence the shorter exposure, that's is why you can get fast shutter speeds on the SPC.

You are correct, using a 2x barlow makes your set up F10. I am not sure that a higher F number is better for imaging, actually I would have thought it was the reverse. My old scope was F11 and I used a 2x barlow to take it to F22. My current scope is also F5 and a 3x takes it to F15, a 5x (which I find too powerfull) takes it to F25.

Some people use up to F30, but in my experience everything has to be perfect to get reasonable images.

A higher F number is usually the result of a big barlow on a long focal scope and goes hand in hand with high magnification, trying to get a big image.

If I buy a telephoto lens of 300mm focal distance at F5 for my camera it costs about £300. If I buy a 300m lens at F2.8 for the same camera, it's about 3 times as big, weighs a tonne and costs about £1500, so a lower F number is the thing to go for.

Hope this helps.

For a beginner f30 is tough going but this is the way to go if we want the most detail from an image. I would say a 3x barlow with an f5 scope giving f15 is a good place to start.

Dag123 has a 2x barlow so if the lens will unscrew this could be used as an extension tube with a 3x barlow giving him the option of f25+.

Robin your powermate will be producing more than f25. On the tv website it quotes a figure of 7.7x when used with a CCD camera although for me it is producing 6x so f30.

[Space Cowboy]

Well I had another try this evening, slightly better results, although when uploded to the forum the image has a blue tinge which isn't present on the original here.

Settings:

[Philips SPC 900NC PC Camera]

Resolution=640x480

Frame Rate (fps)=15.00

Colour Space / Compression=YUY2

Exposure=-5

Brightness=51

Contrast=35

Saturation=-11

Gamma=2

ColorEnable=255

BacklightCompensation=0

Gain=58

Best of 3000 frames capture stacked and then wavelets used to bring out the detail. Hardly any onion rings, well not as prominent, but still a work in progress

200P, with two 2x barlow stacked - approx f20

Very good image Malcolm just needs the blue channel easing back. Be careful using 15fps as there are some video compression ring artifacts on your image. I always stick to 10fps at least then I can sharpen the image more without fear of the dreaded rings.

[tonyowen]

Help, if it is possible.

My efforts are resulting in less and less satisfactory results.

I have a small obj hand guided telescope (75mm, fl 1200mm, f16) and I focus using Jupiter's moons as discrete points(??).

I use a spc880nc webcam (from Morgans) with a uvir filter fitted and run it without modification on a vista computer.

I'm using SharpCap and no barlow (using a 2x barlow makes focusing, locating and holding Jupiter extremely difficult)

My usage of both Registax 5 & 6 do not greatly improve the avi images.

I've used castrator and VirtualDub on the avi's but again nothing extraordinary results.

I've taken note of all of the suggestions and stated thoughts on this thread, but am either missing something important or expecting more than is reasonable from my setup.

Is there a way and offer for a more experienced imager to take 'my best ' avi circa 0.75GB and process it so I could see what could be produced??

I guess I trying to determine what could be expected from my setup.

regards

Tony

[Space Cowboy]

If you know how to transfer such a large file I will certainly have a play with it Tony. What kind of images are you getting? Your scope is very small but you should be able to capture the 2 main bands of Jupiter at least.

[tonyowen]

If you know how to transfer such a large file I will certainly have a play with it Tony. What kind of images are you getting? Your scope is very small but you should be able to capture the 2 main bands of Jupiter at least.

Thanks Stuart

Attached are two registaxed images from the same avi.

using wavelet has not 'apparent' effect

If I expand them, in for instance, Photoshop I lose all detail.

Any info comments welcome

regards

Tony

reg01Capture 19_11_2011 18_39_40.tif

reg501Capture 19_11_2011 18_39_40.tif

[dag123]

Hi everyone, I managed to spend quite some time over the weekend with my scope pointed at Jupiter. With the new motor-drive I am consistantly able to get captures of 1000-frames, which from what I have read is enough for stacking.

I have attached what I think are the best reults. I took 22 AVIs in total. I played about with the gain and brightness mostly. These seem to make the most difference. As before I was using wxAstrocapture. Focus was achieved with the fully-automatic settings trying to get the 4-moons as in-focus as possible.

The settings that seemed to produce the best images from registax were: brightness: 50, gam: 0, gain: 5-10, shutter: 1/33, fps: 10

Knocking the brightness down to about 30 also worked if the gain was increased to about 15.

With brightness greater than 50 and/or gain greater than 15 then the white band in the middle of jupiter was too bright or ended up with a purple splodge!

As a bit of an asside, but also quite cool and a surprise for me.

I took my 22 AVIs over a 90minute period, 1000-frame-captures more-or-less evenly spread out. I put each through Castrator and the Registax with the default settings. Some were quite poor due to my playing-about with the settings, but if I flipped between the resulting images I could actually see Jupiter rotating! This was something I had not expected to see. A quick Google told me that the rotation is about 10hours and so I am pretty sure this is what I was seeing.

SpaceCowboy, am I right in thinking you are suggesting I could get a 3xbarlow and then put this inline with my 2xbarlow to get x5? I'm just wondering if that is a little too much for my scope. Certainly the tracking would be much harder.

dag123

[DrRobin]

Hi Dag,

I would try the 3x and if it is going well try both, but as you say tracking (and focus) will be hard.

Great set of photos and yes Jupiter's rotation is seen. You can theoretically see half of the surface, but if you exclude the edges where no detail is seen (it's seen side on) then I reckon you can see about 1/4 of the disc, so features are going to move across in about 2.5 hours. You can see in the features move in your 90 minute time frame.

Stuart, I think the 5x Power Mate does give a little more than 5x, I measured it as 5.27 with the Lifecam and 5.63 with an SPC. I haven't repeated the test with the DFK. This was measured in daylight by measuring the size of a brick in pixels of a nearby building. The same resolution was used for all tests.

[Space Cowboy]

Very nice images Dag you are doing great! A 3x barlow with your 2x barlow tube would give you the option of bumping up to 5x (f25) which is no big deal for that size of scope. My first scope was the skymax 127 (5") and a 2x barlow with that scope is roughly f25. I actually imaged Jupiter at f40+ with good results (not that i'd recommend that in most conditions).

[Space Cowboy]

Thanks Stuart

Attached are two registaxed images from the same avi.

using wavelet has not 'apparent' effect

If I expand them, in for instance, Photoshop I lose all detail.

Any info comments welcome

regards

Tony

Tony these are good images especially the first one. Your processing looks ok though maybe lacking a little saturation. That first image does look nice upscaled 200%.

For the size of scope you have that is an excellent result. I'm afraid the only way to produce images with more detail is to get a larger scope