pipnina

2 hours ago, Pitch Black Skies said:

That sealed the deal for me, thanks.

I hope you enjoy your new cam and filter set!

1 hour ago, iapa said:

Have you checked that the laser itself is collimated? 

I just gave it my best shot at testing it. I locked the collimator in place, took a reading, then rotated it 90 degrees. So now I have 4 pictures at 12, 3, 6, and 9 oclock.

It can be a bit fiddly and I think one of the rotations I may have not seated it properly, since it's the only one that appears to disagree with the other readings. Is this a good test? What do you think of it?

17 minutes ago, Ratlet said:

Not sure about the technique, but on the silicone front, you probably want to use a neutral (also known as alkoxy) silicone.  The other type (which is most common) release acetic acid when they set and will smell similar to vinegar.  The neutral stuff is meant to stick better to certain plastics and glass.  It's the same stuff as you'd use in the bathroom, but will normally say on it if it is a neutral silicone.

I do recall the sealant I used having an odd smell to it, so I think it's probably not neutral. Does it cause the stickiness to lessen over time or does it just not smell pleasant?

I gave my 130P-DS a sniff since it had already been sealed, but the smell seems to have dissipated by now.

@alacant You've suggested to me in the past using a silicone sealant to hold the primary mirror, is the type of sealant used for putting around bath and shower edges in the bathroom appropriate? I have a tube for sealing plastic bits of showers against tiles and glass. I used it on my 130P-DS, but while that allowed me to remove the mirror clips, I didn't notice any difference in how it held collimation (maybe because my 130P-DS held quite well even before, at least by my standards).

Do you recommend using the sealant in only certain places (i.e. for the 130P-DS, the mirror sat on 3 cork pads, would you recommend a line of sealant at the outer edge of the pads or a covering?

Cheers.

1 hour ago, Elp said:

It's all about the processing and removing LP gradients, with narrowband images are much cleaner and easier to process I find, each sub however needs to be exposed for longer in NB I tend to use 2-3 minutes typically, sometimes 5 minutes at f6.

Narrowband sure does reject a lot of light. I've done 10 min subs and my signal is barely above the noise floor of the camera (no light pollution in individual subs though!)

But because the optical contrast is so high, those 10 min subs are almost usable as pictures as-is, as long as you don't zoom in!

Can you show a stretched individual subframe? If the banding doesn't show (or doesn't show in the same pattern) there, then you could have issues with the stacking algorithm.

Which program are you stacking with? DSS, Siril, PixInsight?

8 hours ago, Pitch Black Skies said:

Looks great 👍

I wonder if something similar would be possible from Bortle 8/9.

I had given up on the idea of LRGB but maybe there's still hope.

https://www.cloudynights.com/topic/662843-galaxy-imaging-from-bortle-89-skies/

Seems like people here can still get great results. No doubt it relies somewhat on local air turbulence from the city and sky transparency due to atmospheric pollution etc, but while light pollution makes images noisier, it doesn't make imaging impossible thankfully!

8 hours ago, Pitch Black Skies said:

Okay, I'm almost there.

So I will be imaging from Bortle 8/9.

Is it even be possible to image LRGB from a heavily light polluted city with mono?

I'm trying to decide on whether to buy a set of LRGB with a filter wheel, or simply just buy a single Ha instead and add an Oiii and Sii later down the road.

Not quite bortle 8/9. But I took this recently in twilight (no astro dark that night) and near the most light polluted part of my bortle 6 sky. One 10 minute sub of red green and blue, processed in pixinsight. No flats or anything.

So 30 minutes of RGB total with my f4 200mm reflector, and there's already signs of integrated flux nebula on the right.

Light pollution makes things slower and a bit more awkward but it doesn't make it impossible. I could have taken 30 minute subs and still had room for more exposure (7000 ADU peak in the nebula, out of 65000)

My equipment still needs a lot of work to make me happy with it all, but the results it can put out in terms of speed are still surprising. Not regretting the mono switch so far.

(edit, I accidentally claimed to have a 200mm refractor... I am not actually made of money haha. Also I said the IFN was on the left, but it's on the right edge of the image. I am a bit tired)

3 minutes ago, DaveS said:

I run a set of 2" Chromas in the ODK (Bought before they became stupidly expensive) and did a trial to determine filter offsets for the autofocus, but when I found that the difference between RGB was less than the difference between runs of the same filter didn't bother going further.

If your equipment in your signature is accurate to when you took the readings, that would be consistent with my findings between my f4 and f5 scope. If you have a slower scope the chromas are parfocal in practice... Just not when you get down to f4. Your f6.8 and f7 scopes would be very tolerant of focus position. That said, the difference between the focus position of the LRGB set and the narrowbands (and between each narrowband) was quite considerable, enough to move the middle line out of the bahtinov pattern from an LRGB to my OIII filter.

My 36mm chromas (LRGBSHO) are great but I have no context for whether they're worth the extra £££ or not! They gave me a very detailed optical density scan (broad 300-1100nm, all filters) and narrow (e.g. 645-665nm for the H of my SHO). I don't know if other's do that. I have heard that Chroma and Astrodon are the only brands that totally avoid halos around bright stars with all 3 major narrowband filters, but when I point towards a bright star using my hydrogen filter i can see odd reflections regardless of filter orientation, so they aren't impervious (maybe this is a result of using an f4 scope, since dichroics change their bandpass when you drift out of their designed working angle, f4 is their lower limit advertised and I suppose any reflections from the corrector will have more eccentric angles perhaps)

Unfortunately, even my LRGB set which was made from the same pane of glass in theory, are not perfectly parfocal. The shift is small but on my f4 scope it's noticable (wasn't so much on my f5, it was tolerable there). So I'd say an autofocuser is a must if you don't have one already.

If you do have an auto focuser however, then mixing brands won't hurt you. You could buy a cheaper LRGB brand (afaik they're most tolerant) and then put the big £££ towards Chromas or Astrodons when it comes to narrowband later on.

Just steer clear of optolong, I have not seen much good from them personally...

I didn't know these products existed! I knew that professional observatories use systems like this all the time (such as the large binocular telescope's adaptive optics system that splits the sodium line from the image into the AO wavefront sensor), so they might not get that pending patent approved unless the patent system is as broken as I suspect it is.

I had thought of an idea where using three dichroics and the right arrangement of angles for the cameras, three mono cams could be used to create "one" shot RGB or SHO, allowing a single telescope to collect colour images at full efficiency. Seemingly based on this the camera behind a filter would sadly see astigmatism, so perhaps it can't work out.

It would also be interesting if this kind of system can work well, if a full-frame sensor could be used at video speed in combination with one of those tip/tilt adaptive optics systems available to us. Since getting stars from within the field would improve their function and help us get tighter stars in our images.

37 minutes ago, Clarkey said:

I had a quick look at some of you images and there is definitely something going on. In terms of the reflections they are odd. Looking at the size they look like they should be from the filters - the same problem I had with my F4 newtonian as shown below. However, the reflections are very different in location. Also looking at one or two of the other images suggests the collimation may be out in addition to some tilt. There is also a weird diagonal on the Baader Lum focus test?

Even though I had no problems with the F5 newt, I did find getting the F4 Photon right was a real pain. I ended up buying a concentre and a new laser collimator (after new focuser and CC) just to get it somewhere close. Not sure this really helps you, other than to say the TS F4's are not easy to work with.

Indeed my collimation may be beginning to slip a little and I'll be breaking the laser out and the . At the next opportunity I will try testing my Ha filter without a corrector in place to see if it remains. These filters are quoted to work at f4 and chroma is supposed to be top-shelf so I wouldn't expect the filters to be at fault- but it can't hurt to check!

The diagonal in the baader (and the halo around the star) are likely because in my attempts to clean it, I had made things worse. I only have normal glasses cleaning spray and a soft kitchen towel (not micro fiber, very soft however, I keep buying microfiber cloth and it keeps disappearing!). When it comes to equipment that's currently in-use, my approach to cleanliness is to stop it getting dirty in the first place if I can help it, but I thought I was finished with the baader so I toyed around with it a bit (took it apart after noticing a threaded insert in the scope end).

I also agree that this f4 scope is definitely a handful. I have a cocenter which seems to show the secondary having been central and in the correct tilt from the factory, and a baader laser collimator which agrees with that assessment. The laser's dot appears near the edge of the ring on the primary mirror, which seems like it's probably in tolerance to me, unless others know better? I do know that on the laser's own marker, the dot does move from one side of the central hole to the other as I slew the telescope over on dec, but I have collimated it when it is upright so the total movement is not that considerable... Unless even that small movement is enough to upset my images. I'll try and get some pics of the collimation tomorrow.

I have done various tests now with a bunch of hardware combinations.

Hydrogen alpha reflections:

All I've tried so far is switching the CC out for my old Baader MPCC. This showed the same pattern and intensity, so I think if changing the corrector is going to solve anything, it's changing a corrector that I don't own... Didn't get to test it without a corrector that night because it had already reached nearly 1PM and I was coming down with a nasty flu that I'm only just recovering from now.

Vignetting:

The vignetting issue seems a little more interesting. I tried my astrocam with the GPU and the Baader CC and it seems as if the GPU MAY be causing greater vignetting (33% compared to 25%?) But I also noticed that when I tested vignetting with NO corrector on my DSLR and astrocam, that the vignetting pattern changes to be off center. I suspect this might be because of the reflection off of the edge of the secondary mirror.

I also checked my astrocam without corrector and without filters (so the only things in the light path were the bare telescope, bare camera and the focuser barrel. This produced the same vignette pattern as with filters, so I don't think the filters are the cause.

Tilt:

Sadly my focus tests for tilt weren't very effective, since I didn't turn on guiding and the stars trailed.  I do notice however that the diffraction spikes in the up-down direction (i.e. the direction the focuser would be tilting in, in theory) are split on both correctors, but not on the left-right direction, where the spikes remain singular/intact.

I have some raw files I took if anyone wants to try drawing their own conclusions: https://drive.google.com/drive/folders/17_3ZrMSXAWTfo7O-aUCVFx9kAmT-84GM?usp=sharing

I got my scope set up last night and, while waiting for it to get a little darker before switching to my main target for the night, decided to try out a single-frame of S H and O on the elephant's trunk- just to have a hubble pallet image under my belt as the last 3 nights have had their own issues which again perpetuated into last night.

This represents only 10 minutes per colour, single images.

I'm quite pleased with the result, despite the very low SNR. I even made an alternate version where I swapped S and H around to make a HSO version, which came out purple.

As for the issue... I noticed my images getting darker and darker through the night, for the last 3 sessions. Tonight I went out to have a closer look inside the tube to find that the secondary AND primary mirror were both totally frosted-over. It was surprising I could get ANY image from it given how bad it was. The outside of the telescope was practically dripping, and I was surprised my laptop still worked, it was absolutely soaked!

I definitely need to find a solution to this dewing issue if I want to continue imaging in summer. Does the fan at the back of the scope (my TS Photon) prevent dew or is it just for getting the scope down to outdoor temps faster? I have seen some secondary-mirror straps which I could get from FLO but don't know what would be most appropriate for the primary mirror.

After identifying that my new scope (TS-Photon) which is supposed to have a 25mm 100% illuminated zone and a 38mm 90% zone, actually has (based on putting the properties I've measured into newt-for-the-web) a 0mm 100% zone (diagonal too small) as well as focuser vignetting on account of the camera being too far away (flats show 33% loss of brightness at 31mm diagonal sensor), I have considered how far further out different coma correctors REALLY move the focal point.

The TS-GPU in use on the TS-Photon at present claims only 20mm, but this cannot be true as (based again on newt for the web) I would need to move the camera at least 80mm closer to the secondary mirror in order to achieve the 100% zone claimed by the manufacturer.

I have just been at the dining table with my 130-PDS and my nikon, to do some basic tests on my old setup when pointed at something some considerable distance away (order of 7 miles).

I first affixed my camera to the scope using a blank M42-focuser adapter, so no lenses involved, only mirrors. I then focused on this radio tower about 7 ish miles away, measured (as best as possible given the odd shape of a DSLR) the distance between the focuser knob and the camera lens flange. About 33mm give or take. Then I did the same but with the Baader MPCC MK3 I had left over. This pushed it out to about 42mm, so with my error in measurement that's a 1cm outward movement of the focal plane.

I am yet to test if the effect differs for my f4 newt in the shed, as tonight I am planning to collect some O3 data and don't want to disturb the camera's rotation. But I intend to do the same test on the f4 scope and also include the TS GPU cc that I have and see how they all differ.

Does anyone else have any correctors to test? I have heard that Wynne-style correctors produce a VERY well corrected image but push the focal plane a very considerable ways out.

I second the above comment, it sounds interesting!

I would guess that beyond the red part, we'd see some purple. There is a lot of NIR floating around in daylight so it may be hard to discern from the background purple-ness that induces in full-spectrum DSLRs however.

For UV I have a harder time guessing. I think our CMOS sensors are typically only sensitive about 50-100NM below the visible spectrum on that end because there is a harsher dropoff.

58 minutes ago, alacant said:

Hi

Can you simplify this? Fighting a monochrome setup is, well...

Borrow a DSLR or osc and get the rest of the hardware working first perhaps?

A few bits to try.

-To begin with, give yourself a chance: go with a powerful Ubuntu LTS gaming box.

-Get a proper GPU cc. These leave the focus position unaltered and come with a graph and chart giving the correct spacing wrt focal length.

-Get the latest indi/ekos/kstars from the repositories. We'd also recommend building the latest versions from git. Try that too.

Cheers 

The only cc I can find is the TS GPU, which is the one I am using at the moment, but claims to push focus out by 20mm https://www.teleskop-express.de/shop/product_info.php/language/en/info/p6706_TS-Optics-NEWTON-Coma-Corrector-1-0x-GPU-Superflat---4-element---2--connection.html

After making this thread I decided to do as you say: I used my laptop (Ubuntu 20.04, i7-6700HQ / 16GB ram, high enough end to have a USB C port back in 2016 when I bought it) in place of the raspberry pi, and had it only hosting the indi server and running PHD, while my desktop used Kstars to remote control the PHD2 app and indi drivers. That much seemed to solve the computer issues, though I think I will have to get a mini PC of some sort as, despite leaving so many thousands of £ out overnight already, that laptop is quite expensive and also needs to be used for work quite often.

I avoided using it in favour of the raspberry pi originally as the RPI was cheap and many had claimed it to be effective for the purpose, and my laptop had some issues with kstars which have been resolved with recent updates (such as crashing on platesolve and failing to move the mount during the polar align routine).

11 minutes ago, Clarkey said:

I ended up using the SW Aplanatic but it does stick out. I used a parfocal ring to hold it in the right place. With the Baader ST focuser it did not give any tilt issues. However, putting the ST on a 6" scope was a bit of a challenge.

Hmm, in theory the SW Aplanatic is the same as the one I am using (TS-GPU), just rebranded GSO stuff.

What kind of parfocal ring were you using?

Also: I think with our focal point so far out on these scopes, we might be inherently vignetted by the focuser. I put the properties of the 8 inch photon into this site and it shows a pretty grim story:

https://stellafane.org/tm/newt-web/newt-web.html

25 minutes ago, Clarkey said:

From my rather rusty quantum theory, it must be the same photon for two reasons:

Firstly got the atom to emit energy it needs electrons to move from one specific energy state to another and will only emit certain wavelengths. Given this is not the case, it cannot be happening. (Hence the ability to look at emission spectra).

Secondly, if the photon was to be absorbed and re-emitted it would be in a random direction.

As for the reflection mechanism itself...🤔

Going back to the OP, I only have experience of the F4 TS scopes. In the case of my 6" version I had to replace the focuser, flock the tube and buy a new CC to get reasonable results. Also, I had horrendous reflections that were impossible to filter out. I  going to try it with a OSC camera later to see if this helps.

Unfortunately AP is a frustrating hobby with all its quirks. I have missed countless imaging sessions due to something not working. As stated above, gradually get rid of the problem kit and work methodically. When you get that one excellent result the pain goes away. (Well, mostly). I wish you luck.

 

Which CC worked for you in the end, and what focuser did you use to replace the default one?

Also yes, when things are working it does make it all feel worth it again.

I got this as a little test when I got stuff working reliably on the computer side, and just about got the telescope OTA to look collimated and mostly untilted. Quick 10-min sub in Ha on the elephant's trunk. I'm honestly surprised that I got so much in so little time.

arcturus ha test - filter facing scope.fitsarcturus ha test 2 - filter facing scope.fitsarcturus lum test.fits

27 minutes ago, Ratlet said:

I've never been more annoyed with my own ignorance than I am right now.  I feel for you buddy and I really hope that someone will be able to help.

Do the reflections persist even with no filter in the train?  I'm just thinking the issue might be internal reflections in the tube rather than the filter themselves.  Perhaps the lrgb have lower enough transmission to prevent the reflection being visible whilst your higher spec chromas are allowing the reflection through.  If they persist without the filters then you know it's not the filter.

If it's the tube then flocking might be a solution.

 

Luminance filter seems clear of it (I forgot to turn my light panel off so it has a gradient however. These three show luminance filter, and hydrogen alpha with the coated side facing the camera, then facing the telescope.

EDIT: This person has a similar issue, but I don't see if they have chromas too or another brand, but they do have another reflecting scope: https://www.cloudynights.com/topic/731527-first-light-zwo-asi294mm-pro-mono-edgehd-11/

1 hour ago, Rallemikken said:

Many things here, I'll focus on the "Raspberry PI 4". I don't trust theese small gadgets to run a full KStars/Ekos/INDI session, if that's what you are doing. To many toss away KStars and Ekos because troubles like those you describe, common for them all is that they try to run their rig from a PI, either a homebrewed setup or commercial.

How many run their gear with a grown-up laptop or computer, with KStars/Ekos/INDI under it's native OS, Linux? Well, there must be more than just me....  How many of us bring all kinds of frustrations to this table, trying to sort out all kinds of weird behavior and bugs? None. as far as I know, but I'm kind of new on this forum.

I'm a newbie, I fired up my rig for the first time on the 14. sept. and closed the season on the 8. april. On 64 degrees, to light summer. My log for my first year has 39 entries, and my harddisk has 45 new datasets. Not a single crash or hangup, not a single instance of "weird" behavior. Once the initial settings was sorted out, things just worked. The only thing I will continue to tinker a bit with is the guiding, but that's a thing we never settle on...

My rig is run by a HP EliteDesk 800 with Linux Mint 20.3 _64-bits. If you can't take your computer out, or the evenings gets to cold, consider running a PI on your rig as a pure headless INDI-server, and connect it to your computer that runs Linux/KStars/Ekos/INDI with an ethernet cable. Takes some effort and skills, but it's the nest best. I set up a PI3 B+ as an exercise and did a test with my Canon 600D connected. It was impossible to get the PI to consume more  than 152 mb of the PI's 1 gb, and the CPU-usage never got over 7,5%.

Btw, don't put anything between a camera sensor and the secondary mirror in a reflector. Period.

I can try running it using my laptop tonight, so try and eliminate the RPI as the issue.

My laptop and desktop are on Linux (laptop is on Ubuntu 20.04 Gnome, PC on Manjaro KDE), but my laptop has had its own quirks with Kstars/Ekos, namely it crashed when trying to platesolve, and wasn't able to use the polar alignment feature either.

Not sure why you think nothing can go between the secondary and the sensor when a key part of all reflector imaging trains (unless planetary imaging, but then barlows are common) is a coma corrector or field flattener etc. Plus many professional observatories have very complex optical systems with numerous mirrors, filters etc. Maybe the stuff I have between my secondary and sensor aren't right for my scope, but I don't see what's wrong with the concept.

When I first computerised my mount I expected this hobby to become a bit easier, and certainly for the level of automation to make me able to image more frequently and collect more & better data when I did. Sadly since I made the move to a cooled mono cam with this computerised setup my imaging life has been anything but stress-free.

Has the quality of my images gone up? Certainly. Has it introduced numerous independent problems that make me generally unsatisfied with my equipment, even though it has more than tripled in cost relative to last year? Unfortunately...

Whether it be poor flat frame calibration (neither 130-PDS nor TS-Photon 200/800 are free from this...) tracking/guiding woes, collimation challenges, suspicious levels of vignetting, filter reflections, computer errors, heavy mono cam & filters sagging the focuser or plain not sitting straight, the TS telescope not actually being compatible with their own coma corrector... It's all left me very sad and frustrated and with far less imaging time and lower-quality images than I expected if these problems did not exist.

When I finally got fed up with trying to tinker with my 130P-DS, and went for the only real option in my budget at the moment without sliding backwards in aprture and focal length (TS-Photon F4) I realised that while this scope solved one issue (PDS compression-fittingless focuser and barrel intrusion) it introduced several more such as the coma corrector pushing focus so far out, that the tube can't extend far enough and the corrector has to sit about 3-4cm pulled out, meaning from the stock of the focuser to the flange of my camera I now have a whopping 12cm gap, which is just ludicrous and creating a massive torque on the tube and focuser when my 1.5kg of camera, filters and CC are sitting in it parallel to the ground. This shows in my images as well as stars change shape throughout.

Then the filters, I adopted the "buy once cry once" approach and bought chroma 36mm, which are supposed to be an ideal fit for APS-C sized cameras. But while the LRGB filters seem to be working fine, the even more expensive narrowbands produce horrible reflections around bright stars, no matter the orientation:

As you can see the reflections are present in this 3nm Ha filter whether the coated side is facing the camera or the telescope (I flipped the filter wheel around). This is only a 60s exposure of arcturus. I guess my hopes of a good narrowband session near orion's belt are shattered now! This pattern doesn't show up in lum, so it's definitely something to do with the narrowband filters.

Then there's the suspicious vignetting (ADU in a flat or the background of a luminance frame) of about 50%! This scope advertises it's "90% illuminated zone" at being far larger than the diagonal of my camera... And I have already reduced the distance between my sensor and the filters as much as the 17.5mm backspacing built into my cam allows.

And perhaps most frustrating of all, my mount wants to just... turn itself off randomly as of late. Sometimes the INDI control panel says it's outside of its alt-az limits (even if I turn those limits off in EQmod, it still does it), sometimes it claims it wants a meridian flip, sometimes, just nothing at all. All I have to do is press the button in ekos to start tracking again but not having to babysit the scope was meant to be an advantage of computerising it! Plus the drift it causes means I have to re-create the framing all over again.

At this point I just don't know where to go with this hobby. It's so so good when things are running well, but oh so horrifying when getting death by a thousand cuts when so many thousands of pounds turns out to be not so well spent as expected... What do I do!? Where do I best direct my current astro-savings project money to?! So many problems and (after the computer and camera upgrades) not enough money to just splash out and hope high end gear will fix it.

If anyone has any ideas I'll gladly hear them, because this is getting ridiculous : (

I am not entirely sure 36mm is quite enough, although its very close. I have a fairly considerable drop in ADU in my flats even after getting the cam as close as possible to the filters (20mm or so? Backfocus built into cam plus filter wheel internals) On a scope (TS Photon F4) that's meant to still be above 90% illumination at the edges of an APS-C sized cam.

The asi EFW retaining rings for the filters does trim a mm or so at least off of the edges of the filter diameter, maybe it has something to do with that.

3 minutes ago, vineyard said:

Do you recalibrate the mount model every time?  I used to have this - I think its something to do with the mount model vs the EKOS model.  When I started basically re-calibrating the mount model at the start of every session (even though it was on a pier so thankfully no PA required every time) it got better.

Maybe also trying posting a query on indilib.org?

Recalibrate? I'm not sure what you mean by that as I thought the mount "forgot" everything when it powered down, and assumed it was in the park position at switch-on?

Is there a specific routine I need to run?

I noticed this once or twice before, where I'd wake up having set the rig to work, and realise half my subs were just star trails as tracking had turned off randomly. When I most recently set up my kit, it did this while I was setting up and trying to set the focus on the scope and saw the star drift out of my zoomed in live feed.

Not only that, but once I got it taking pictures, it would randomly decide to perform a meridian flip (seen in Ekos' EQMod log), (pointed at Sadr, so absolutely no need for one) and the first I would notice was PHD telling me it was "insufficient to correct". Not sure if it succeeded at moving the mount for one or not because PHD stopped looping at that error message. I'd park the mount and try again, and sure as the sun rises it happened again. Does the HEQ5 circuity have any of this logic built in or will it ONLY perform movements when instructed by the handset or EQMod driver PC? If the latter, then I can rule out hardware issues and blame either my Raspberry Pi or Ekos for whatever is going on.

I've intentionally avoided system updates to avoid regressions or software bugs being introduced, and it wasn't doing this until recently.

I checked the system time, which was correct, and the slew accuracy and using EQMod control panel to slew to RA/DEC coords sent me to the right places, so time should be right. I added my GPS to 3 decimals taken from google maps in Kstars so in theory that's fine too... Ekos has been a good software setup and IMO more intuitive than N.I.N.A, but it has been riddled with bugs too, anyone else experienced this one?