Kon

5 hours ago, neiil phillips said:

Good to see you doing some lunar imaging kostas. Some subtle mineral color coming through.

Good to see you back at SGL. I hope to do some close up imaging soon.

18 minutes ago, Flame Nebula said:

Thanks Kon, 

Would the 715mc be useful for dso with an Ed80, (at F6)? 

Thanks 

Mark 

Sorry Mark, but I do not know as I do not do DSO imaging. You might want to ask the DSO experts.

What Geof said above (it was me who suggested the 715mc on the other post; you are looking 5x the pixel size of the camera and your telescope is f10 so the 715 will not need a barlow to get the correct sampling). You will also need an ADC as Saturn is fairly low in UK to cut through the atmosphere. Yes the camera will be good for all the planets (and moon) not just Saturn.

For the price of a powermate, I would get a 715mc as you will be at the correct sampling without  the need for a barlow.

I think your setup is fine. You want to be at 5x the pixel size, so for your camera around f19 so the 2x barlow is right (your 8" SCT is f10).  An ADC will also help with targets that are low. Jupiter and Mars are ok without one for the next apparition assuming you capture when they are high up.

In most cases, it is down to the seeing. The 224 is an excellent camera and the barlow is fine too. The barlow coatings might make a difference when you start doing UV imaging.

If seeing is good, it is worth getting as many videos as you can and derotate them in winjupos as it will help with noise. If seeing is bad, you will not be able to save the session and it will always be a soft image. Collimation is also key to pull the fine details.

Not the best seeing last night despite the clear skies. Waxing Gibbous at 97% illumination. Stacked 40 images and pushed the saturation a bit to reveal the mineral colours. 8" Skywatcher 200P Dob, Nikon D3200.

Another set of excellent images Mike. I really enjoy your images with their very natural appearance.

Great images. You have done an excellent job under the conditions as you have resolved the small craterlets very nicely. Nice delicate colours too.

6 minutes ago, Flame Nebula said:

Hi Kon, 

I didn't recognise the name, but as soon as I saw his profile picture, I knew exactly how good his images are. Absolutely top drawer! However, for me the resolution of a 16" dobsonian is beyond my plans. But sure does put a C14 to shame! 

Yes hard to miss his images. From what we discussed offline and what you want to do, the seeing will be your major limitation. A summer house in Barbados or Spain will give you the weather you need 😜.

I am not a DSO imager, but have you seen the posts/discoveries from Bray Falls of filamentous like structures (nor sure if it is in the same area)? Could it be something similar? He seems to be going quite deep with his imaging.

Fantastic images by the way.

4 minutes ago, Flame Nebula said:

Thanks Kon,

Very impressive photos by the way! 👍

My intention wasn't to be unfair🙂, but rather that I hadn't found any that I liked yet. I was looking for very specific things too, so perhaps I should have made that clear, as I did see lots of good photos taken with dobs, just not within the criteria I was searching for. 

I'll have a look at Tom's photos. 

I would love to see what you can do with that 12 incher! 

Mark

 

What will limit you in UK in terms of imaging is the weather and location as planets do not rise high very often. I am envious of friends from mainland Europe with constant good seeing.

Some short of tracking will make your life easier.

Nice images. It seems you had better seeing for your colour capture as it is sharper. Lovely subtle mineral colours.

Nice images. You have resolved the craterlets and rilles very nicely on the close ups.

11 hours ago, Elp said:

You need to speak to @Kon

Although I do not have a VX 10 or 12, I have been extremely happy with my Skywatcher 200P (8") Dob. It is hard work and at time frustrating but you can push it to its limits. These are a few of my manual captures on Jupiter, Saturn, Venus and ISS. I have recently got a 12" GoTo but I have not had good weather to test it properly but I love the fact it keeps the planets at the centre of the camera without nudging it every so often. And, yes it is big compared to my 8".

13 hours ago, Flame Nebula said:

but I've not found any images I really like that used dobs.

Have a look for Tom Williams at Astrobin, possibly one of the best planetary imagers. He is using a 16" GoTo Dob. Loads of good examples in SGL too with Dobs (most GoTo) so it is a bit unfair to say this. Have a look at the planetary imaging section at SGL from @Space Cowboy who is using a Skywatcher 10" GoTo.

This is my first ISS with the new 12" Dob. I do not have tracking ISS with the GoTo yet but a friend is helping me out. Awful seeing with a 5 min break between clouds. I focused on the moon and even with the IR filter it was boiling. Only 7 frames were of decent quality to stack. Several modules are visible, SpaceX Dragon, Progress and Soyuz. 12" FlexTube GoTo, asi462mm, 2.5x TV powermate, IR 685 pass filter.

14 minutes ago, orion25 said:

Bravo, Kostas! 🚀

Thanks Reggie. I can't wait for the planets to be back again.

You are aiming for 5x the pixel size of the camera. The less elements between the camera and telescope the better.

I never found benefit from binning but you can try during the processing.

I am not a DSO imager but I recently got a second hand 12" Dob and I was getting flaring in Jupiter's moons. I thought it was collimation but in the end I had some pinched optics; is it likely to be after you cleaned the mirror that you may have tightened the clips around the mirror a bit tighter? Just a thought.

Great first effort! I am sorry you are hooked into imaging 🤑.....I am glad I got into planetary than DSO as it seems to be a much more expensive part of the hobby. Enjoy and looking forward to more of your posts.

2 hours ago, bosun21 said:

Excellent image Kostas. I will have to try Uranus myself before it's gone. How do you add the colour when using a mono camera? I guess that's going to be another thing to learn. I recently acquired a 462MC so I'm now wondering whether it's worthwhile adding the mono version for IR filter captures. The collimation doesn't look that far off in this image.

Thanks Ian. Yes give it a try; I captured this one jsut after sunset, it does not need to be dark as long as you can find it. I love my 462; I have both the c and m versions. Both are excellent in IR sensitivity so you can use your c for IR captures. The only reason I bought the m was for Venus due to its sensitivity in UV. I used the m last night as it already had the filter on it. Your c with an IR pass filter is effectively becoming mono.

I added the colour in Gimp (or whatever software you use for editing) by colourising the planet layer only. 

Regarding collimation, the moons are not perfect and you can see why I keep pushing to get it to work, but I found the problem and resolved it, most likely pinched optics (see my other long thread).

I think I have a solution. It was probably pinched optics; I took the primary out and although the retaining clips where loose (credit card could fit), it was the side nylon screws between the retaining ring and mirror that I had tightened quite a bit. Collimation and star test revealed nice concentric rings and no flaring at the stars. Out of focus star (the infocus was awful to make any judgments).

5 hours ago, Ratlet said:

What angle do you have the scope at when you collimate?  I made the mistake of collimating with it flat when I tilted it up to observe the mirror would shift slightly and affect the collimation.  Now I collimate at 45°.

I'm not doubting Mr Spock's diagnosis (he knows far more than me) and is probably correct, it's just afaik there is nothing to be done about astigmatism, so I'm grasping at straws.  Also I think the GIFs you post have a fair bit of seeing going on and there are bits in the second gif that makes the star look out of alignment from the diffraction rings.

Not flat but at a high angle. My issue is flaring on Jupiter's moons thus my concern something is not quite right.

5 hours ago, Mr Spock said:

What you should do is repeat the test with better seeing to see if the distortion is consistent. If it is, -

First thing to check is if it is the primary or secondary. If it is the primary, the oval shape should change direction if you rotate the primary cell.

If it is the primary, check to see if the mirror is being distorted by being held too tight.

Same if it's the secondary - it's probably miss-mounted or being gripped too tight in the cell.

If either of the mirrors is astigmatic themselves and it's not mechanical, then the only cure is refiguring 

I will give it a try with rotating the primary. Regarding the secondary, there is no cell just the glue at the back on the he holder, the standard skywatcher setup. I will rotate the primary and if it persists in the same direction, is it likely to be secondary?

4 hours ago, bosun21 said:

Looks like a case of bad seeing and atmospheric turbulence to me. I have saw similar images while attempting a star test under such poor conditions only for them to resolve on a subsequent night with decent seeing. I would definitely wait for a better nights seeing before exploring the dodgy mirrors avenue. You said that the mirror clips are loose, but just how loose? They should still be able to hold the primary in position albeit without placing any undue pressure on the mirror surface.

I agree seeing is not great but stars at the eyepiece are not pinpoint but have a bit of flaring. The clips are not touching the mirror as far as I can tell, but I can do the credit card check. There are 3 nylon screws between the retaining ring of the cell and primary that I have quite tight, these are on the side. Could that be it? I will loosen them and check.

1 hour ago, Pete Presland said:

Excellent captured and processing. The Moons have come out really well, what was the method used to expose the Moons. Some sort of layering technique?

Thanks Pete. Yes the moons were added as another layer; they are from the same capture and popped by stretching the image.

26 minutes ago, Mr Spock said:

The oval shape is a sign of astigmatism.

 

if so, what's the remedy? Or nothing it can be done? But I wonder how much it is bad seeing. I need t orepeat the star test with my camera. Unless the primary had not cooled down although it was out for a good 3 hours when I did the star test.