My CarbonStar 150 Newt has a (small) flare issue and I need your help!
HTML-код
- Опубликовано: 1 окт 2024
- My Patreon: / cuivlazygeek
My Merch Store: cuiv.myspreads...
To be fair, the flare issue isn't a big deal to me, it's just something I'm wondering about!
Primary Mirror Mask: www.thingivers...
Musou Black Paint: amzn.to/3Xtordw
Amazon affiliate: amzn.to/49XTx01
Agena affiliate: bit.ly/3Om0hNG
High Point Scientific affiliate: bit.ly/3lReu8R
First Light Optics affiliate: tinyurl.com/yx...
All-Star Telescope affiliate: bit.ly/3SCgVbV
Astroshop eu Affiliate: tinyurl.com/2va...
Further Notes!
- The mirror mask is painted with Musou Black Paint
- A lens hood with the inside painted with Musou Black Paint didn't do anything
- The coma corrector doesn't intrude in the light path (it is below the baffles)
- Some Patreon supporters noted that ZWO cameras have screws near the sensor that could reflect light, I'll try painting them black and/or swapping the camera!
- Patreon Supporters also suggested painting the side of the coma corrector that has threads with Musou black paint, I'll try that!
- It's not the OAG/guider prism, since there is none! I'm using the ZWO ASI2600MC Duo!
- Other suggestions welcome!
-----------------------
My equipment
-----------------------
Dwarf III Smart Telescope: bit.ly/3SyChXu
Seestar S50: tinyurl.com/3n...
ZWO ASI2600MC Duo: bit.ly/3M8IkPS (Agena) or bit.ly/3Jti7KQ (HPS)
ZWO ASI585 MC Pro Camera: bit.ly/3Iwo6y8 (Agena) or bit.ly/4cp1Ofn (High Point Scientific)
TOUPTEK IMX571 APS-C Cooled camera: tinyurl.com/mr...
TOUPTEK IMX585 Cooled camera: tinyurl.com/4y...
OGMA versions (use code CUIV on checkout for a small discount!): getogma.com/
CarbonStar 6" Newtonian: bit.ly/3W7ZFiA
Mirror Mask for CarbonStar (designed by me :) ): www.thingivers...
SW Quattro 150P Budget Newt: bit.ly/3BABCxl
Backyard Universe upgrade kit: tinyurl.com/3j...
OCAL Collimator: s.click.aliexp... or s.click.aliexp...
Askar V Modular Telescope: bit.ly/3Imoq2M
or bit.ly/3GLuyR8 or tinyurl.com/2h...
RedCat51: bit.ly/48hyuVx (Agena) or bit.ly/48pTWXW (HPS)
Cable Organizers: www.etsy.com/s...
WarpAstron WD-20 Mount: bit.ly/3wxNbGI
ZWO AM5 Mount: bit.ly/3Qb5xVf or bit.ly/3JeVUkn
ZWO EAF Focuser: bit.ly/45agP0Z (Agena) or bit.ly/4avCIcE (HPS)
Antlia ALP-T highspeed filter: bit.ly/42RBR2e
SVBony Filters: amzn.to/3yBuQZX
Mini Computer (newer version): amzn.to/49XTx01
Flocking paper/Felt paper: amzn.to/3zASgvu or amzn.to/3m94zwa
Follow me!
My Instagram: / cuivlazygeek
My Facebook page: / cuivlazygeek
My Patreon: www.patreon.com/cuivlazygeek
To be fair, the flare issue isn't a big deal to me, it's just something I'm wondering about!
Further Notes based on my Patreon Members feedback (since they B5+ had access to the video early and without adds)
- The mirror mask is painted with Musou Black Paint
- A lens hood with the inside painted with Musou Black Paint didn't do anything
- The coma corrector doesn't intrude in the light path (it is below the baffles when at best focus)
- Some Patreon supporters noted that ZWO cameras have screws near the sensor that could reflect light, I'll try painting them black and/or swapping the camera!
- Patreon Supporters also suggested painting the side of the coma corrector that has threads with Musou black paint, I'll try that!
- Other suggestions welcome!
Primary Mirror Mask: www.thingiverse.com/thing:6610187
Musou Black Paint: amzn.to/3Xtordw
Amazon affiliate: amzn.to/49XTx01
Agena affiliate: bit.ly/3Om0hNG
High Point Scientific affiliate: bit.ly/3lReu8R
First Light Optics affiliate: tinyurl.com/yxd2jkr2
All-Star Telescope affiliate: bit.ly/3SCgVbV
Astroshop eu Affiliate: tinyurl.com/2vafkax8
check to see if the edges of the secondary mirror are flat and not bevelled
Not just caused by reflections, can be caused by impeded light path - for example the focuser sticking out into light path. But what you are seeing (flare outward towards the edge of image) just looks like not perfectly corrected coma.
Hey Cuiv! :) I think next step should be making some test images with NO coma corrector, sure you'll have horrible stars at the edges but if you don't see the flares and only ablong star shapes, it should point to the coma corrector. Cheers
Agree with this, remove everything, then add back until the flares are visible again.
This what I also thouhght of. And maybe test it wiht another cam, yo have two of the same kind, so maybe swap them? Good luck!
Those are excellent ideas, I will try that - seems the CC is on everyone's minds!
This was my thought as well. Could be a defect in the coma corrector. Either that, or some funky nonuniform deformation in the main mirror
I had a similar issue on my 14" TS-ONTC in combination with a paracorr 3". There were two factors that contributed to the effect.
1.) I had a bad custom adapter: the coma corrector was placed slightly tilted and off centre through this adapter.
2.) the mechanical and optical axis were badly misaligned. I had to tilt the whole focuser (featherthouch) to align the two.
One symptom of this would be, if you need to adjust the secondary, so that the distance of the backplate of the secondary mirror is not evenly spaced to the secondary mirror holder in order to get good collimation.
In essence, both effects had placed my coma corrector at an angle, not perpendicular to the light coming from the secondary.
After correcting both errors the flares were gone.
From Highpoint Scientific (Aug 6 2024) : "On the most recent batch of CarbonStar Newtonians that Apertura has sent us, there have been three main improvements to the scope. These upgrades include a larger locking screw on the focuser, and a primary mirror cell that has been modified to make the optics less sensitive to there being too much pressure on the primary mirror, pressure which may cause odd star shapes in your final images. There has also been a change to the rear light cover and they are now redesigned and made from injection molded plastic which fit better and will last longer."
It's awesome they're making enhancements, and I heard they're also sending stuff to existing customers!
My first thought was focuser protruding into the OTA. The flaring would be more pronounced always on the same side relative to the sky. But I would be looking at your OAG. Try taking it out of the train and do some test shots and see what happens. Also if you can rotate the OAG to your camera and see if the flaring rotates. Blackening the secondary will help but i don't think thats a problem.
One thing i did notice on my newt a while ago, had some strange fine diffraction spikes. Turned out a spider had laid some lovely silken threads inside the scope. A swirl with a soft brush and al, fixed.
Thanks for the tip! The focuser isn't protruding and I'm not using an OAG (using the 2600MC Duo), but I'll check spider webs too :)
Would the primary mirror mask also fit on the Quattro? Asking because i have the skywatcher quattro 150 and was planning on printint a mirror mask😅
I don't know but I suspect not...
given the orientation of the flares (always pointing towards the outer edge of the FOV) my best guess would be the backfocus distance. You can check backfocus distance using the hocus focus plugin in NINA, also check for field tilt on ASTAP. Fast scopes are very sensible to backfocus distance and if you dont get it right you might end up with these kind of issues
Can check that for sure, but that would be a first for me - I've been very loose with backfocus on the other Newt, and I haven't seen that issue there - but I'll check!
I agree it looks like the pattern you can get with the camera too close to a field flattener. Consider adding a millimeter between the comma corrector and camera and see if this improves.
Do you have flare without the coma corrector in place? Of course without the coma corrector, you will observe coma. If so, a fix might be to blacken the edges of the lenses (requires disassembly--not for the faint of heart). Oh, and are the coma corrector optics AR coated?
I'm suspecting the coma corrector!
Have you ruled out minor pinch optics take a long exposure of a really bright star so you can see the diffraction spikes better, I cant imagine that anything is in the way of the imaging trained on this since its seems that they had everything in mind to make it for astrophotography.
I haven't cared enough to investigate more, but I will soon try to switch the CC from the Quattro with the CS and see if it's better! That way the cause could be isolated!
I had the same problem with my GSO 6" F5. I solved it by changing the entire secondary mirror for another one with a slightly larger diameter.
Very interesting!! Were the GSO secondary mirror edges painted black?
What size mirror did your swap it out for? I have the same scope and am very interested as I am having the same issues as Cuiv. I have a primary and secondary mirror mask, flocking, and painted the edges of the secondary and I still get very small spikes like Cuiv. I remember reading on CN that the secondary might be the cause because it is slightly undersized.
@@user-pi5xu7qs7n 54mm. The original size was 52mm.
@@CuivTheLazyGeek no, they are not painted
I would swap out the image train (comma corrector, filters, camera, etc.,) from the Quattro and put it into the CarbonStar. That would eliminate a lot of possibilities very quickly and help you to isolate the problem. (And yes, you absolutely should blacken the spider veins).
Good idea! The spider veins are blackened on the inside, which I think should be enough for now
I have this on my 6" Newt and it's related to your coma corrector and collimation. You could try to make the collimation better, but there is a good chance that it will not going to be fixed perfectly, if at all. It might be the curse of an F4 scope and short focal length and using an APS-C size sensor. It might be the secondary mirror being too small or the coma corrector can't correct for the sensor size, I don't know. Most fast Newtonians struggle with anything bigger than a 4/3rd size sensor.
Thanks! Collimation is fine now, but agree the CC is likely culprit
Cuiv, my train of thought to is that it's possibly a coma corrector issue. Definitely something in the imaging train. Also, double check the the prism in the OAG hasn't drifted slightly into the camera sensor path.
Thanks John! No OAG (ASI Duo) so that's not it, but CC seems a likely culprit!
Hi Cuiv, why do you want to avoid blackening the edges of the secondary mirror? They are painted black on my TS ONTC telescope.
Print a mask (a circle) with a diameter that obscures a bit more than the secondary mirror, put it in front and check
That's a great idea! I'll try that, very easy to put in place!
I second that❤
CC might be intensifying the issue still issue from caused by the spider?
I would play the elimination game to find out what is causing it.
Dang, I will have to wait for the next video to know....good stuff buddy.
I was thinking about buying a CarbonStar and ran across this video. I will wait to buy until I see a resolution to the problem here.
Hey Cuiv,
Just a shot in the dark; but what kind of paint did you use for the back of the spider? Is it by any chance somewhat reflective?
Hello
Checked subs from my Carbonstar and noticed no similar flares….my guess is backfocus or reflections from the secondary
maybe a mirror defect from the secondary or primary, my skywatcher has the same problem,i google searched and found a few owners got a refund and an email qouted from skywatcher that the problem can't be fixed,they didn't say what the issue was . try a even larger mask, see if it's any issue like a turned down edge .
Perhaps you could swap the image train post coma corrector with the SkyWatcher, just to rule out anything specific to that portion of your image train?
What would useful is a front dust cover that doubles as a cover at the other end to prevent light leak. Has anyone tried 3D printing such a thing? Is there some obvious reason why this isn't done that I have missed?
I see something very similar on a rasa 8 (has a diffraction spike mask installed) not as bright and have to pixel peep on some stars but still there. So I would be very interested to find out what is course is in your case is.
Since the flare brightness goes in the *opposite* direction of coma, could it be an issue with coma corrector spacing in the optical train? Perhaps try a different coma corrector....
Hey Cuive hw are you.
Have you thought weather the main mirror is either cut slightly to shallow or to deep as the flaring is fairly symmetrical. l just an idea
Is the focuser axis right on secondary mirror axis, or in other words, is the focuser collimated ?
I am pretty old and I have never seen a spider and ring in such a lovely red colour! All I have ever seen is vanes and rings that are black. Might it be the spider and ring or even the secondary mirror holder? I am used to seeing everything black in the path.
I'd use a lit small white light LED and move it around in front of the spider while running your camera in video mode, and see if you can localise where the reflection/flare is coming from.
Good idea!
since the flares are behaving like in the case of wrong back focus (going outwards) - maybe you should check the reducer/corrector ...
Thanks, seems to be the main suspect indeed!
I guess it may come from secondary miror ... Can you try with the one from your Skywatcher, do see if it make the difference?
Seems like a back focus issue being made worse with possible collimation issues.
Cuiv I feel your pain. I’m desperate to try my 10” Quattro on my WD-20. I’ve never tried a little planetary camera with the Quattro and the coma corrector and it’s give all kids of weird results but 30-60mins before clouds roll in doesn’t give much time to,troubleshoot.
Hope you get it figured out!!
I would take out the primary mirror and do a simple knife edge test to check the figure on it. It might have a very slight astigmatism. A zone mask would be best to reveal if there is a specific zone on the mirror being affected, and might be able to be masked if that is the case. A very technical suggestion, but one that would clearly eliminate the potential of your primary being the source for the flares.
I'll check the coma corrector first since it's an easier (and potentially likelier) suspect!
Like other comments, maybe swap out the corrector with another if you have it and compare both against having none. That will eliminate the corrector as a problem.
Check your back focus, maybe the camera chip is not in the sweet spot. It looks like a slight spherical correction is needed to get a truly flat field.
I also would blacken the secondary and primary. Why the primary? Because coatings always leak a little light and I like to cover all bases.
You showed the update about the hood, which I would keep just because of the light pollution in Tokyo.
You can only test 1 change at a time if you really want to know which thing solves it. Lot of time but... Oh well...That's why we keep throwing wrenches in the machinery, isn't it?
Obviously it is coma. Not ideal comma corrector or some other optical element.
I'm going to start calling you a Pixel Peeper! PS - I'm a Pixel Peeper. Something is obviously going on and you will eventually figure it out.
I'm having severe problems imaging with my Newt without proper dew control. This has me concerned over the Musou Black Paint since it is water soluble, does it come off (re-wet) with dew?
Aaah, because of wind I don't have much dew issues on this balcony, but that's a good point I hadn't thought of... I think it would need to be rubbed to cause issues, but would need to test it out!
Have you tried imaging without the comma corrector? And another idea might be to flock the inside of the OTA. I’ve done my Sky Watcher SkyMax180 and it made a massive difference to contrast in its images.
The inside of the OTA is already well painted and baffled, but the outside threads of the CC aren't, so I'm suspecting this!
I think this looks like the secondary mirror is too small. Of course that sounds silly, but looking at High Point Scientific's page on it, it says it's designed for 'smaller' sensors up to a 4/3. Also, the focal reducer would make that effect worse. I'd bet if you removed the coma corrector, or used one that didn't change the focal ratio, the issue would be reduced. I might also bet that a smaller sensor, like the 533, would show no issue at all. No hard evidence for this. Just a hunch.
Good point there! I'll definitely check on the CC first, and potentially a secondary mirror mask
Hi Cuiv:
Have you tried Hocus Focus in Nina? It highlighted all sorts of problems with my fast Newt.
I'll try it out :)
Maybe you have a pixie fairy living inside the tube and it's flying around creating reflections. But in seriousness spider webs can cause reflections like this and can be nearly impossible to see. Seems unlikely with a new telescope but you never know.
Ok you actually have multiple issues. One is the flaring that follows the outside which seems like a smudge or artifact on your coma corrector try spinning the image rig and see if it moves if so check the c.c. don't use filters in that test, if it doesn't move than I'd say there's still pinching or stigmatism in the main mirror. The next one with the potato or egg effect which might seems as tracking or collimation which it isn't. It is caused from the focuser tube edge slightly impeding the light path. My 8" oouk newt did this exact same thing. Whats going on is that you need to get the focus tube as far out possible but not let light get in through the focus tube area. its bit of a pain because you need the focus tube almost all the way out but enough room for the eaf to do its thing without binding or free spinning the focus nob. Use tape to mark its travel path unless you have measurement markers on the tube. So you have to move the camera, spacers and coma corrector to get this exactly right. On my rig i can't get prime focus if i use a oag or filter wheel/drawer and get rid of the egg shapes, just the c.c. spacers and camera. My c.c. is the baader mk3 so it has a short tube compared to the starzonia. The reason this happens is because the main tube is too close to the main mirror size. On mine it's about a 13mm clearance when it should be about 25mm on each side of the mirror. I hope this helps.
Thanks so much for this! So looking at pictures taken yesterday with the 585 camera and its tiny pixels, I actually see a tiny bit of pinched optics so I'll remedy that first! But I don't think it will fix the issue - I'll exchange the coma correctors from the two scopes to see what happens at some point :)
As for the elongated stars, it was indeed collimation - fixed after a quick collimation session :) the focuser tube itself at best focus is well below the baffle edges inside the tube and doesn't intrude in the light path at all! The Quattro did and I had already done and documented the procedure you describe :)
Thanks so much for taking the time to describe all of this, I love this hobby and the community around it!
I have the same telescope. At first, the images were like yours, a flare at bright stars. After re-collimation, most importantly, secondary mirror height (downward for several turns), the flares were disappear. I uses OCAL for collimation.
That's great to hear! The secondary looks well centered, but I'll have another look!
Hey Cuiv, which free tool did you use to design the mirror mask? I have a new scope coming (ZWO 153F4) and documentation on it is quite sparse, so I may have to do what you did and design my own. Something I've actually never done before!
I simply used Tinkercad, together with trigonometry!
Like someone else said in the comments, I would suggest taking some images without the coma corrector in place. Since the flares change depending on the location in the image, it could be reflections coming from a poorly coated or baffled coma corrector.
Yep, seems the CC is a prime suspect, thanks Dave!
Something I've not seen suggested yet, could it be something to do with the baffles? Maybe there's a slight defect/dent on the edge of one of them.
Is it possible that light is reflecting off the sensors, then off something else and then back again? With the Duo, this could cause uneven flaring since there will be more reflection on one side.
Have a close look at the coma corrector, maybe there's a defect or a bit of hair stuck inside it somewhere.
I know all these are unlikely; I'm just throwing out ideas in the hope that one of them is useful.
Thanks for the ideas! The baffles seem unlikely, but the other stuff are an idea... Swapping the imaging train from the Quattro is a good idea :)
Just a random thought, and probably more trouble than it's worth, but could you swap the mirrors and see how each scope performs? Provided the specs are the same. The primary wouldn't be too difficult to swap, but the secondary could prove to be a can of worms.
Possible, but not for my lazy arse! I'll rather swap the CC/imaging train!
Did you paint the edges of the mirrors black? Protect the mirror reflective surface with cling film before painting the edges. I plan to do this with my Sharpstar 130mm f2.8 HNT. Also check back focus using hocus focus
Thanks! Not yet, but might do that - however I want to do that as last resort!
Hey Cuiv, I'm thinking it's caused by the sides of the spider being painted red. I know you probably don't want to paint them but I would try since spider veins should be flat black on the side that can reflect light along the path to the mirror. BTW, absolutely great videos and have watched and continue to watch all of your videos on RUclips! Keep Looking Up and enjoying the journey ✨️ Cheers!
A lot of people are suspecting the CC, but that's also a possibility, I'll check!
Does it seem like there is a soap solution left after washing the solution off the mirror? I encountered a similar problem on the Quattro 800/200, the solution to which was to light-proof the focuser tube.
Thanks for the tip! The mirrors look clean, but you're right the focuser tube and shiny CC threads could be the issue!
Wow bad issue :/ I may have a solution : buy a refractor 😄😏
Ha! I much prefer the Newts for now, despite this issue :) And refractors aren't free of their own issues either :)
@@CuivTheLazyGeek c’est compréhensible 😁
You're assuming the mirror(s) are correctly shaped/ground.
Always a chance they aren't/it isn't.
True!
Newtonian’s just aren’t worth it. I’m selling my 8” Orion because I’m just not geared to deal with all these little issues.
Nah, I disagree - Newts are in general awesome :)
Use aperture mask to test edges . I had similar issue in my scope , i blocked edges of scope with different sized aperture masks and then finally 3d printed one that eliminated issue . In sct corrector plate ring is not smooth in my case , it might be different case in your scope .
Great idea! I'll look into that!
To me it seems to be something caused by the coma corrector/reducer, maybe its just the design of it that has some flaws, or maybe a faulty unit.
Thats my guess at least, something to do with the focuser/coma corrector/spacer/camera. Could also be the focuser protruding inside the tube, but I dont think it causes that type of issue
The coma like nature of the flare does rather implicate the corrector (inconclusively 🙄)
Thanks! I'll check with another CC, and maybe also flock the threads on the current CC!
Could it be that the edge of the secondary mirror has chamfered edge that was aluminuzed either partially or fully?
Good idea there too, I'll have a look!
If yoy are 1000% sure it is no light leaks or reflections then, I think, the culprit is the coma corrector. Not exactly sure how or why but simoly through the process of elimination. It can't be the camera, reflections or other common issue like the mirror clips.
Perhaps the coma corrector has some bad coatings and is somehow partially reflecting light or is having light reflected onto it? (Highly unlikely as no oag is oresent in the optical train). As someone else has suggested, get rid of the coma corrector or swap it for the quatro cc. While you're at it try changing the camera because you never know in this hobby 😅
I'll try with the Quattro CC! First I'll try to add some flocking to the CC in front of the lens :)
Check your secondary mirror. It is possible to have something in the edge.
Interesting! I'm still waiting for clear nights to test mine but I'll watch out for this and report back. I do have a different camera (Player One 533M) and different coma corrector (Skywatcher quattro).
Trying to paint the secondary outside edge might be a good test but if the paint is washed away by water, dew might make a mess there. Last thing you'd want is that paint dripping down on the primary :)
Eeek, good point on the dew...
My newt does this, but not every time. I found that the mirror can shift/tilt as you slew to your targets, the telescope is now leaning on a different side than when you collimated. The focuser tilt can also exaggerate this or completely eliminate it as it settles into a position.
Your mask reduced it simply because you reduced your light gathering.
I can recommend while you have it collimated with a laser, move scope around to see if the mirror tilts around, or simulate camera weight on the laser and see if it tilts
Thanks for the info! I’ll try that before imaging tonight.
@@aaronwilliams3949 good luck with it. I’ve really leaned into this being the culprit since the flare isn’t always on the same side, and even doesn’t happen at all. I did lagoon recently, and having it point south and only at a 20 degree angle, completely eliminated the flare that I had earlier that night when pointing the opposite direction
Primary mask screw heads reflection? Grasping at straws sorry. Swap them for hex screws see if shape changes, maybe
Others have suggested secondary mask, coma corrector issue, or painting spider sides black, I'll look at these first as more attainable!
POINT to the RedCat ;)
(more seriously: how close to that first baffle height are those focuser screws inside the tube?)
The baffle seems to be fully hiding the screws from the optics so I think it should be fine!
Surprising that Apertura hasn't seen this issue already. What about High Point Scientific? Didn't they work with Apertura in designing this telescope? Have you talked to Hight Point yet?
Yep, I'm checking with them!
Could it be the OAG intruding into the light path?
Thinking the issue could be with your camera. Possibly the gain or sensitivity needs adjustment.
I don't believe so - cameras don't really add such artifacts (except stuff like microlensing on the 1600MM for instance, but that's symmetrical across the field), and I'm using the bog standard unity gain...
Ah oui c’est vrai c’est une Duo j’avais oublié 😂
What’s it like without the coma corrector ? Interesting issue and I hope you get it resolved.
Will try without (or with a swapped) CC!
Is the focuser protruding into the scope? How does the secondary mirror look? Did you blacken the front red outer ring when you blackened the spider veins?
No on the first one, secondary looks fine as far as I can tell, the outer ring is also blackened... :( Bit of a mystery!
I have a carbonStar on order so I hope you find out what this is. From your video,I did see the coma corrected looks very shinny and might need to be painted. Do you also have other set of the Batman Appetizers you can put on it to see if that makes a difference?
Good idea on the coma corrector! Will implement that first :)
I added a mirror clip to mine did you eliminated this completely. Ask Sean from visible dark I used an embroidery hoop... Completely solved it for my Skywatcher 250P
I'll have to look into it!
@@CuivTheLazyGeek it really works fantastic. It did wonders on my fast Newtonian with my nexus corrector. Trevor was having kind of the same problem and I told him about that too. It eliminates those type of flares completely. And the amount of f-stop that you lose? Is minimal.. these Newtonian so fast you don't notice the point 3 decreased in F stop..
Maybe you should defocus bright star and focus it until flares appear, maybe you would see something.
Good point, I can try that!
Make like a black widow and black the spider fully or at least the sides. If you have another black spider that would fit, try swapping it out. I think the spider is the issue. While you have blacked the back of the spider, the sides are still fairly reflective and given the low angle of incidence, its possible light is reflecting off the side of the veins and flaring. If you've blacked all other possible sources of reflection, then what's left must be the culprit.
If you are worried about painting everything, try masking tape/painters tape and then paint the tape black, so if the veins are not the issue you can just pull off the tape. Same thing about the sides of the secondary mirror, mask and paint OR mask, remove, paint, remask OR paint tape and then mask. You like to tinker, so tinker. :)
Thanks mate, good point on the spider sides as well!
Because the flares show up all around the center perimiter, it does seem that the field is not flattened. As you said the mask will remove any issues with the mirror clips. Also I think if you have round stars anywhere on the image, but oblong stars in the center, that is not a tracking issue but an optics issue. Have you performed anything like a focault test? I'm sure as you know, the shorter the focal length, the more perfect optics have to be. That said, collimation may help because it looked like the spikes to the right were worse than the spikes to the left. But still I wouldn't think you would have those erroneous spikes anyway leading to question the quality of the optics.
I now have better collimation, so the stars in the center are nice and round (and even to the edges) - rather than the mirrors, I suspect the CC ..
Quiv, in my experience the secondary mirror may not be in the correct position. Meaning the direction “in”, or “away” from the primary mirror. The position may be off center slightly.
Thanks for the tip! Using the OCAL, I can confirm it's well centered but someone else suggested adding a secondary mask, so that could be it. The main suspect seems to be the CC though
I'm pretty sure it's the focus tube that sticks a little into the light path. it looks like this when you look down the telescope. look through the focus tube and see if you can see a bump on the main mirror when you are not perfectly centric. Even if you don't think it is this, take a look. Look for something that is asymmetrical.
Thanks David! Unfortunately that's not the case - it's fully behind the baffles in the tube!
It almost looks like coma. Maybe backfocus is a bit off or something is off with the coma corrector
I'm suspecting the CC!
Check if your coma corrector is protruding inside the optical path when you are in focus.
I used to screw on filters on the bottom of coma corrector and they were protruding inside light path which caused weird looking artifacts on bright stars
The CC isn't protruding, but could still be the root cause!
Could the flare be coming from your coma corrector????? Think about it.
Looks likely indeed
Hey Cuiv, I have the same scope and coma corrector, I am also using your mirror mask (thank you for this btw!) and I have recent subs from the same target! Let me know if you would like to have a look at them to compare. Anyway, fantastic content as usual! -PF
Oh yes, please let me know if you see anything!
@@CuivTheLazyGeek I am not seeing the same pronounced flaring that you are. I do however have some oblong stars in the center of my image similar to yours. I just got an autocollimator and its showing that my collimation is still slightly off so we will see next imaging session. I posted one of my initial results of the same target on the CN carbonstar thread where your name has come up quite frequently XD
Hi Cuiv, that may be related to reflex in front of the coma corrector. Next time, try to add a short M48 spacer with flocking inside. Helped me a lot.
Thank you! A lot are suspecting the CC, so I'll check that!
I think you answered your own question. "...my collimation is really bad" You certainly should be collimated very well before looking for other problems!
No, as I mention later in the video, the symptom is still there with good collimation :)
I suspect your scope is based on the GSO 150mm. If you have the GSO focuser have a look at the nice shiny rail on the focuser. In my example the focuser tube extended well into the light path.
Good idea! I'll have a look :)
@@CuivTheLazyGeek those mirrors are extremely good, one of the local vendors here in the UK gave me some private test results and they were of a surprisingly good standard... alas the focuser is good but struggled the moment I tried to add a filter wheel... I replaced it with a Baader steeltrak that cost more than the scope... trying to get a focuser to fit the 150mm tube is hard, most are targeted at 200mm tubes.... I have 3d printed a mounting block that should allow any 70mm spaced hole focuser to be mounted.. let me know if you want the .stl ... good luck
Ross
Id paint the sides of the spider and the secondary mirror but my bet is a reflection off the coma corrector. Maybe swap the imagining train from the quattro as mentioned
A lot are mentioning the CC, it's the next one on my list, but also the sides of the spider!
your backfocus is not correct
Hey Cuiv! My friend, these are simply "stab in the dark" suggestions, but have you considered internal reflections coming from the actual Mirrors themselves? Maybe one of the Mirrors has a slight manufacturing defect? Or possibly the Coma Corrector? Apart from that I honestly cannot think what else you could do to rectify the flaring? Hopefully you'll get to the bottom of it at some point! Thanks as always for the great content my friend! Wes.
Thanks for the idea Wes! Seems most are suspecting the CC, so I'll start there!
@@CuivTheLazyGeek ☺👍
Sure the focuser tube is not intruding into the main light path INTO the scope? I had this flare with the 130 PDS right for this reason. Usually does not apply with a 150 but I don't know that scope easy and quick check.
I would also first suggest trying it without the coma corrector and with a different coma corrector. Another thought is that the secondary mirror surface figure is good in the center but worse around the edges. If it is a bit undersized for the camera you're using, this could cause issues at the edges of the field but not the center. Looks to me like diffraction/scattering rather than a stray light issue.
Good points, the CC will be the first test, but the secondary seems a likely second suspect:)
What a weird issue! I would check for a hair or something on the image train, like on the end of your field flattener?
Will check thanks!
Hi Cuiv, sort of the same problem here with the GSO200/800 and Baader coma corrector. It was bad, but almost gone now. (Because of 56mm backfocus instead of 55mm.)
First I noticed I miscalculated the backfocus and was a few mm's off. Secondly I found the secondary mirror off a touch by axial rotation, which solved almost everything. If however the scope is on the other side after the meridian flip, it's a bit more prominent again. Some Tilt I guess?
Hope this helps. Clear skies!
Nice review! I remember that you compared refractor/newton telescopes recently. I know that you have an inclination towards newtons even if, sometimes they are not easy to use. Would be nice to see a comparison about the "difficulties" using two refractors... and see if you are still in favour of newtons telescopes. I am a traveler and I do not want to gamble with newtons issues (collimation issues... and others)... now you know my preference! 😇🕶
I think they're very easy to use! But the initial setup until perfection requires a bit more effort :)
@@CuivTheLazyGeek Perfection with a lot more effort! Too much for me! 😂
Try also to floke the focuser tube and at the same time use a dew shield. Your light polluted skies are a source of light coming from everywhere. If that does not work, I think you have a bad mirror set. Hope this helps
Good idea, will actually try flocking focuser tube and the inside threads of the CC!
I'm not so sure this is necessarily a light leak. Would recommend double checking your back focus and looking for internal reflections in your image train.
I should add that my F4 Skywatcher Quattro 200 is very sensitive to back focus
I think internal reflections in the CC are a likely culprit, I'll check that!
Cuiv, the artifacts you are experiencing remind me a bit of the artifacts one encounters on SCTs that have dew rings attached. Do you have some kind of anti-dew device attached? If so, have you tested imaging with the anti-dew turned off?
I have a similar problem with my sw 200/1000 newt. Solving the problem for me: the primary mirror is stretched.
Pinched optics?
@@CuivTheLazyGeek yes
Hi Cuiv, I've had a similar issue for years but with my old
C100ed R, the spacer between the lenses has an air space spacer with three tabs that stick out into the light path, so annoying as three wierd shafts of shadow come out of brighter stars on my pics, no idea why celestron had let this go, although at 900mm it's not an ideal or fast imaging scope, but I still like it.. I've been toying with removing the cell as there are wipe marks visible with led white light between the lens which have been there after assembly at Celestron!! , so ime getting courage over some years😂 to either cut tabs down on spacing ring or add a thin ring mask on outer lens to cover them. It all means removing separating cleaning, and re mounting accurately etc, whilst maintaining collimation.. I may just leave it, leave it or break it tends to happen in my case... 😁 Atb Tom..
No red surface (or any other colour than mate black) must exist in the telescope, in any direction, inside or outside the scope. You will have to choose. Good looking telescope on outside, or good imaging telescope. And keep in mind that any edge inside will create reflexions, even if is painted black. Think at the photographic lenses diaphragms, which are very thin, but still creates flares. The sides of the mirrors could be painted black also. And a hood will help.
i guess try imaging without the coma corrector and filters - at least you could eliminate that.
Good idea!
Bonjour 😄, je pense aussi que cela peut venir de ton OAG, essaye sans , sait-on jamais ... 🖖
Pas de OAG puisque j'utilise la 2600MC Duo, mais c'était une bonne idée!
Coma corrector internal reflection. I have the same thing on my Quatrro 8.
Seems a lot of people have the same thought, I'll check it!
Hi Cuiv! With no reason in mind, have you tried a dew shield?
Yes! No difference!
hi dony worry to much it is just the remains of a fly caught by spider....or perhaps the eyepiece holder and its tube intruding ?? Good luck Athol Bayne