ONIKKINEN

Could be an internal reflection of some sort, but a more pressing issue would be focus. Zoom in and you see stars have hollow and dark cores which means you were out of focus when imaging, so best to fix that first.

1 hour ago, Richard_ said:

Yeah that's right. Good thing you built it then though, imagine trying to buy a good graphics card today! 

My GTX1080 proved to be a great value purchase in 2016. I think it will stay in its socket until it bursts into flames 👍.

13 hours ago, Leonard Abu-Saa said:

Thanks Malcolm  So first step is learn to align properly  

My first attempt on Orion Nebula and Orion's Belt with Sony a6600 + Samyang 135mm + Start Adventurer. 30x15" lights f4, iso 1000; 100 bias; 40 darks. Stacked in DSS and processed in LR + PS.

I live in bortle 6 area, between flats so I can't see Polaris and align properly. I used an app 'PS Align Pro', but with more than 15 seconds exposure I already got trails which tells me that my alignment was extremely poor. Also my editing skills are not that good but I want to improve. If anyone wants to try and get more out of the .tiff file, I can provide a link  

 

This looks great for a first try.

46 minutes ago, Richard_ said:

Of course, it only takes one incident to cause shortages. Back in circa 2012 some fab(s) in Thailand flooded which shut the fab down. This caused a shortage in hard drives / SD cards which is turn ramped the prices up temporarily. We're seeing a similar thing here, but on a global scale.

I remember this as i had just built a gaming PC for myself before this happened. If i recall correctly the prices at least doubled and stayed higher than the before normal pricing for years afterwards.

Depends on the type of astrophotography targets in mind and how much you are willing to compromise in quality and ease of capture on the final images, but yes if the goal is to get any picture of the sky, then a DSLR and a wide lens will do the trick for a lot cheaper than a mount + telescope. Cooled camera + lens + cheap mount would probably be cheaper, though not that much and you get i believe far less for your money.

But how much cheaper really? Not that much cheaper IMO.

Good lenses are more expensive than cheap telescopes, like the 200P. The 200P is actually very aggressively priced, and you cant really find a decent lens around the same price so the difference is waning already (i think a better choice would be the smaller 130 or 150). Then lets say the cheap mount you get is either a star adventurer or an EQ3. Maybe you can get rid of them with a little loss on value after using them for a while, but many people probably still hang on to theirs and cant really get rid of them. This means the price of the HEQ5 will be the price of the HEQ5 AND the cheap mount.

I also think that lens astrophotography is more of an experts choice for someone who already knows what they are doing and knows what they want. Beginners almost always want to do a bit of everything since they really dont know what they are going to be doing yet, so a lens will prove disappointing since you really cant do planetary, Lunar or smaller DSOs. You can churn out mediocre pictures with a cheap newtonian or an 80mm ED refractor much faster than with the lens and learn as you go so i think the HEQ5 + some scope is pretty good advice.

I as a beginner would have never agreed with using just a lens as i wanted to image galaxies mostly. After M31 and maybe M33 the list of shootable targets just ends with the typical camera+lens combination. Most beginners always state the same things: i want to do Lunar, planetary, DSO both big and small and i would prefer to also be able to do visual, and it needs to be cheap. Impossible of course but when you balance the scales and forget about a few or more requirements, you end up with a telescope on a mount 9 times out of 10.

2 hours ago, maw lod qan said:

Just look at all of them you see in the movies standing in the background!

Newtonians are usually upside down though, this one without counterweights too... The Expanse is a fairly high budget series as well so it is quite surprising nobody bothered to do the little research it takes to point the telescope the right way up.

I do wonder what purpose the mount would serve as i dont think there is enough room between an EQ3 and an EQ5 to fit a mount.

Maybe a sort of alt-az/EQ hybrid that also works manually and doesnt cost an arm and a leg like the AZEQ5/6? I reckon that kind of mount would find buyers quickly.

19 minutes ago, michael8554 said:

Well I suppose if the vignetting at the bottom of the Flat isn't apparent on the Lights, you may be right.

But I'd say its vignetting by the bottom of the shutter box, or the step between the circular lens mount and the sensor.

Michael

3 minutes ago, alacant said:

The shadow of the mirror. 

HTH

Could have been any of these actually. Went away with a change of camera into one that has none of the above.

1 minute ago, michael8554 said:

That's not shutter shadow.

1/25s = 0.04s

Michael

Hmm, that went away as soon as i changed to a shutterless camera, so what was it then?

1 minute ago, vlaiv said:

I was just amused by strange wording of image being pixelated and all of that ...

You are right - sub is low SNR in part due to resolution it was taken at. Binning will help with that of course (your calculation on equivalent exposure is right, but not really important here - because when we bin this image it will have equivalent signal as 180s taken with binned pixels or large pixels).

 

My brain is in Monday mode...

1 minute ago, vlaiv said:

How can image be "pixelated" because "pixels are starved for light"?

The image looks noisy because it is noisy?

I dont think im conpletely off the rails here by saying that the image has quite low SNR due to the resolution.

Just now, vlaiv said:

What?

4x4 bin is 16x faster than 1x1 bin?

180/16 is 11,25. So if the image was taken with a 1.2 arcsec/pixel resolution with the same aperture the same SNR would be reached in 16th the time?

33 minutes ago, recceranger said:

Bit of an update. Sadly, the suggested methods didn't bare fruit. I even tried converting from FITS to TIFF to try using Sequator. However, the TIFF images were coming out as well underexposed. I uploaded a TIFF to Ps and using camera raw filter maxed the exposure (PSA image) and it was well under. Not sure why? My ASI533 was set at Gain 100 and these are 180sec frames?

Many thanks for the advise folks. Well appreciated. 

Exposure time alone is just part of the equation and goes hand in hand with resolution. If you did not use the reducer i believe your resolution is somewhere around 0.3 arcsec/pixel so about a quarter of what would probably be recommended. The reason why reducers make telescopes "faster" is they spread out the light to cover fewer pixels so signal to noise ratio improves.

That would mean a 4x4 binned ideal(?) exposure would reach this result in 11,25 seconds = 180/ (4x4) so this exposure is actually very short (ignoring read noise and OSC here, its not quite that straightforward..). This is i believe also why it looks so pixelated because your pixels are just starved for light.

Not sure how i would batch bin subs though. I split my images after calibration to 1R, 1B, 2G subs without debayering so the resulting mono images are half the resolution. That might makr them stackable but still far from ideal.

I had shutter shadow visible in 30s exposures on my lights, so with my 550D i dont think there is a point trying to increase flats exposure time since it will be an issue anyway. In theory though if i somehow managed to take 30s flats it would probably go away, but way too much effort.

Mine were apparently 1/25s or 0.025s and looked like below. Histogram stretched monochrome and a false colour rendering to show the whole flat dynamic range better. The dark patch on the bottom would be the shutter shadow.

14 hours ago, Ronclarke said:

Not the same time but the same set up..

Was the camera removed?

If the camera is removed or something else is changed in the optical system, its almost certain you dont get perfect flats afterwards. If you image with a mirrored system its also possible something moves that shouldnt when the scope is just left doing nothing and flats would also not work. The remedy would be to take flats immediately after imaging, or even before imaging if you intend to leave the scope running overnight while you sleep. If the flats still dont work there are some mechanical issues that need tending because your optics change during the session.

If im not mistaken your Omegon 130/650 has a 1.25 inch focuser? If thats the case its not that well suited for astrophotography since coma correctors require a 2 inch focuser, and vignetting would be an unnecessarily big issue if you use your DSLR.

HEQ5 is most commonly recommended for a good entry level astrophotography mount and fits your budget nicely and leaves some money left for necessary accessories. Dont skimp on the mount, so try to resist the temptation to buy a cheaper mount to leave money for other things, the mount is the heart of the operation!

So an HEQ5 + Skywatcher 130PDS + TSGPU coma corrector (https://www.teleskop-express.de/shop/product_info.php/info/p6706_TS-Optics-NEWTON-Coma-Corrector-1-0x-TSGPU-Superflat---4-element---2--connection.html) would be around 1800e. There is a very long thread here on SGL where people image with this kind of setup and many pictures turn out fantastic:

Without guiding you will be limited in the exposure time you can use, and there will be other nuisances you will have to tend to manually like dithering, framing, finding the target etc. All doable but much easier with guiding in the mix. But this would definitely get you started nicely and get good results already.

For guiding there are options depending on whether you have some of the stuff already. If you have a laptop you could use with the scope you will save a fair bit of money, if not you will go over budget for now. If you do have a laptop you only need a guide cam and a guide scope.

Something like the very simple but effective ZWO 120MM. This is conveniently sold as a package with a simple 50mm guidescope: https://www.teleskop-express.de/shop/product_info.php/info/p10396_TS-Optics-Guiding-Set-50-mm-Mini-Guide-Scope-and-ASI120MM-Mini-guiding-camera.html

Guide scopes can vary in price but the differences are in the focusing mechanism. The above model focuses by rotating the lens cell, which could be annoying to do. More expensive models have a non rotating focuser. But focusing a guidescope is not really that important, it just needs to be good enough and you may find it doesn't bother you.

If you dont have a laptop you can spare, you would need to have some kind of computer on the scopeside. Either a used laptop which can be very cheap, a ZWO ASIAIR which is expensive and only allows you to use ZWO products and some DSLRs, a Raspberry PI running stellarmate software, a stellarmate (same as previous), or the best combination of all of these: a windows 10 mini-pc. Prices with these vary but expect to spend around 300 euros or more.

Without the computer you would be right around your budget with the HEQ5+130PDS+TSGPU+120MMguider package, but there will be additional costs, there always is. You'll need an adapter or two for the coma corrector, you would probably want to invest in some collimation equipment like a TS concenter eyepiece, you might need to buy a power adapter or if imaging in a remote location a battery of sorts to power everything. So maybe drop the guiding for now and stay within budget would be a good route to go.

There are quite a few very obvious hot pixels in the screenshot, although its hard to tell without seeing the actual frame itself if its an issue or not. DSS is not quite scrolled far enough right to see the important parts of the frames = FWHM and number of stars. If all frames have a similar amount of stars it should be stackable, but if all frames have a very low FWHM im willing to bet DSS is counting your hot pixels as stars instead of the actual stars. This would lead to the images being un-alignable and so DSS will only stack 1 frame. You can check what DSS considers as stars by clicking the "edit stars" button.

Just thinking aloud, but If you used the C9.25 and the 533 for the image, which seems likely based on the scale of M51 on the screen and the square format, you would be oversampling by at least a factor of 2, probably 3 or more. This makes the hot pixels look more like stars to DSS than the actual very spread out low SNR stars in the image. If this is the case im not sure how to fix it. If you have AHD interpolation on in the RAW/FITS settings in DSS try setting it to Bilinear or super pixel and see if things change. I dont find it that odd that there would be only 16 stars in the image though, since its such a small field of view.

1 minute ago, dazzystar said:

Thanks for the reply. Not sure what to do now!

 

From the device manager screenshot it looks like everything is as it should be.

So just to reiterate: USB to MC, HC not plugged in. From EQMOD select the HEQ5 option (no EQ3 option available) and set its COM port to 4. This may be auto detected as well. Try a BAUD of 115200 and 9600. One of them should work.

16 minutes ago, dazzystar said:

am I meant to have the Synscan controller plugged in to the motor control box and the USB cable connected to the hand controller too...don't want that. Just want usb to control box.

Options:

USB to HC, No EQMOD

USB to MC, no HC, Yes EQMOD

FDTI serial cable to the HC port on the MC, no HC, no USB, yes EQMOD.

4 minutes ago, dazzystar said:

 

Click on the properties and see if there is an error. This looks correct by the way and it seems you have the GL chip that needs the newer drivers.

And looks like you have them or it wouldnt be recognized.

I would recommend this for secondary collimation: https://www.firstlightoptics.com/other-collimation-tools/ts-concenter-2-adjustment-eyepiece-for-newtonian-telescopes.html

Very easy to use and you can immediately see where the problem is.

You dont mention what telescope it is, or what focuser you have (if you changed it) but if its a stock newtonian and not of a premium quality the focuser is probably not perfect. If you have any slop in your focuser it wont matter how much you collimate the scope because the camera position is not reproducible and so collimation changes depending on where you point in the sky or some other trivial reason.

You also dont mention what camera you have as there could be another reason for it, like shutter shadow if using a DSLR with a physical shutter. Unless you post a raw flat these are just guesses, but collimation is a pretty good guess whether related to actual collimation or focuser slop.

Can you post a raw flat frame, rotated and not?

Not sure i understand the issue but would like to have a look if possible.

Just now, dazzystar said:

Yes I have all the drivers downloaded (probably installed those more than once in frustration!). This is so annoying....

Try the other Prolific driver?

4 minutes ago, dazzystar said:

OK. I'm still having problems. Let me explain what I've tried tonight.

Removed the Synscan hand controller completely and connected the usb cable from my pc to the usb port on the motor control box. Made sure the COM port speed was 115600. Turned on the motor control box and went into the ASCOM diagnostics software, chose  Skywatcher Telescope, clicked on properties then got a big error starting with Failed to load driver: "ASCOM.SkyWatcher.Telescope. 

I then tried connecting the handset back in and the usb cable to the handset and got basically the same error message.

What can I be doing or having done that's wrong people?

 

Have you downloaded and installed the drivers? The lower one in this page(not the synscan app one). I think you have since you have the Skywatcher telescope option in the diagnostics tool but just checking.

https://skywatcher.com/download/software/ascom-driver/

Also the Prolific USB-to serial drivers. (The second download here)

https://skywatcher.com/download/software/accessories/

But could be that your unit needs different drivers. I actually recently received a brand new Skywatcher mount (AZ-EQ6) that did not work with the above prolific drivers. No matter what i did the mount USB or handset USB was not detected by any piece of software and i had no control. It was visible as a COM port but just not functional. Looks like Skywatcher have started using a new version of the prolific serial chip somewhere on the mount and have just not updated their own site. I downloaded drivers here: http://www.prolific.com.tw/US/ShowProduct.aspx?p_id=225&pcid=41 and now USB control methods work just fine. Maybe give it a try?

Its really strange that some mounts work with some drivers and some mounts work with others, kinda embarrassing how bad the situation in something as simple and crucial as a cable connection can be...

Lots of good tips here already, but ill throw my 2 cents on the computer control subject.

Mini-PC running windows 10 is the best deal. You get all the bonuses of running a windows machine on the field but none of the negatives from laptops (bulk, battery life). Any gear you have is guaranteed to be compatible, not just a select few models (like with the ASIAIR) or a select few pieces of software (raspberry). You can run NINA/APT, sharpcap, firecapture, full version of PHD2, proprietary brand specific capture software. You could even process quickly on the go with DSS/Siril and see what youre getting after some subs have rolled in. 

This is also probably cheaper than the ASIAIR.

Negatives: preferably controlled with a tablet. Phone control possible but annoying. Some tinkering and initial setup required so not for complete tech-allergic people.

The way you have the scope set up now is called the "home position" of an equatorial mount. RA (Right ascension) axis and with it the counterweight shaft at its lowest position and the other axis, DEC (Declination) axis at its highest position.

With the mounts axis at this position, try to get Polaris to the center of the eyepiece. Do not touch either of the axis, but do left-right movements by rotating the entire mount on the tripod (have the bolt a bit loose) and adjusting the up-down axis with the latitude adjustment screw. The latitude gauge should be initially at your locations latitude but dont be surprised if you still need adjusting afterwards. When Polaris is centered, tighten the tripod bolt. Once done, do not move the tripod or rotate the mount on the tripod anymore, all movements with the mount will happen with the RA/DEC slow motion controls or by loosening the clutches and manually pointing the scope.

This mount has no polarscope so the polar alignment routine is quite basic and inaccurate. Dont worry about it too much, just get it thereabouts correct.

I usually did not bother trying to get Polaris in the eyepiece but just pointed the mount towards Polaris and set the latitude to my sites latitude, but it will be easier to point the scope afterwards if you do it more accurately.

Now finding objects will be a bit tricky with this kind of mount but the way i did it was to manually point the scope to a bright star (using the red dot) near the object i tried to find and then by using the slow control knobs moved the scope bit by bit until i found it. It will be confusing because left-right in real life is not necessarily left-right in the eyepiece because the view is mirrored and could be at an odd angle.

And of coursr how would you know where anything is? For that i would recommend a planetarium app like Stellarium. In stellarium you can toggle on the setting to "show equatorial grid" (one of the buttons) to get an idea how the movements of your RA or DEC axis move along the sky. 

@vlaivs suggestions are sound IMO. The skywatcher 130PDS is perhaps the cheapest entry level scope to buy and mount that has use both visually and photographically. I think you could mount one on an EQ3 but it wont be fun and you will want to upgrade the mount soon. I would aim for the EQ5 myself.

The best option, one that you wouldnt have to regret later would in my opinion to save up first instead of buying lacking gear now and then saving.

But for visual only you can get a nice scope for around 500. The heritage 150P, a dobsonian is a popular first scope for 320e : https://www.teleskop-express.de/shop/product_info.php/info/p12279_Skywatcher-Dobson-Telescope-Heritage-150P-Flextube---150-mm-Aperture.html

That leaves some money for upgraded eyepieces and extra trinkets. Dobsonians are manual mount/telescope combos in one so tracked long exposure will not be happening with one, but you could image the Moon with it.