ONIKKINEN

I dont think your Jupiter is bad at all. Considering the equipment used its pretty good to my eyes. I also shot Jupiter earlier this year with similar equipment and a similar result.

I used this: https://www.teleskop-express.de/shop/product_info.php/info/p55_TS-Optics-Optics-TSB251-2-5x-Barlow-Lens--1-25-inch---apochromatic-triplet-design.html

and a Celestron t-adapter 2x barlow which is probably very similar to the astro essentials 2x.

The TS2.5x barlow is very good for the money. Visually it is noticeably better than the cheap Celestron. 

Jupiter is getting pretty low in the sky right now which will rapidly reduce image quality the lower it gets. How high was it? I doubt it was much higher than 20 degrees if you shot from the UK. Could also be you had poor seeing that night? Collimation should also be as perfect as possible with planetary. I dont think a bahtinov mask will help with planetary captures, its probably better to just visually focus with live view. Its difficult but looking at the edge of the planetary disk is a good method. When the edge is well defined and sharp you are in good focus. Jupiters atmospheric bands might also be a good visual focus target.

3 minutes is perhaps a bit too much for a single capture as Jupiter rotates very quickly. Try shooting a bunch of 60-120s captures and hope one of them hits good focus and good seeing? You could also try to stack with stricter settings, maybe a 10% stack or similar. With 120fps you have lots of frames to spare.

This is what my try in July looks like, a mostly blurry disk. This is 15minutes of rotation which is shockingly short for such an obvious movement and the reason 3min might be too much. I took 90s recordings and stacked best 35% but only because my framerate was only 38fps.

On 19/10/2021 at 20:25, wimvb said:

Rule of thumb and experience from an earlier life in the semiconductor industry. So far, I haven't seen linearity diagrams for sony cmos sensors.

Doesn't sharpcap sensor analysis measure this or is this some other number?

Not the same camera, or sensor but from the same Sony Exmor lineage of sensors so could be similar. Mine shows sensor linearity to 99,3%. Does this mean the last 0,7% experiences a nonlinear response, or that its overall 0,7%? Never really understood what that number stood for.

I think i have some issues with light panel flats aswell, but unsure if its related to anything discussed here.

On 27/09/2021 at 11:44, vlaiv said:

Flat panels work well with baffled and flocked scopes. Some scopes can't cope with that much light hitting inside of the scope at different angles. Newtonians are prime candidate for this sort of behavior.

I think my issues lie here, i am flocking my tube to see if my flats improve.

4 hours ago, edjrgibbs said:

Calibration succeeded, I used 60s exposure, mount is well balanced and the fl is set correctly as far as I can tell. Odd that it tracks well without guiding but when guiding goes haywire!

I meant the guide camera exposure, too short and youre chasing seeing = good guiding impossible  too long and there is not enough time for corrections. I would recommend  2s exposure at minimum to even out seeing, but not much longer.

You see these errors while guiding because unguided your DEC axis does nothing at all and with a decent polar alignment it does not move. RA is only tracking and experiencing periodic error, which can have a small or an unnoticeable effect on 60s 135mm fl subs. Guiding attempts to correct for periodic error and DEC drift because of polar misalignment etc.

I think i remember seeing that the AZ-GTI needs a firmware update to work in EQ mode properly. You are running in EQ mode with a wedge and counterweights? Because that is a must.

The DEC axis is having trouble with backlash, it looks like. That unresponsive series of corrections and then a sudden jerk that overcorrects is what happens when your worm gear has cleared backlash. This jerky movement could also affect RA if its too aggressive. The RA error could indicate bad guide settings, mechanical issues, balance issues, calibration issues or just be a side effect of a weak DEC axis.

I can think of multiple issues and fixes that i have also come across but really there are too many unknowns to give good advice.

Did calibration succeed, what exposure time are you using, how is your mount balanced, is the guider focal length set correctly etc?

I have the TS 60m f/4 guidescope, which looks like it might be the same as yours but in a different package. Stars are awful, even with a UV/IR cut filter.

But it doesnt seem to matter at all. Focus can be quite a lot out before i notice anything. I typically dont refocus after setup. 

If the Orion 60mm is like the TS, you want to buy an extender (20mm probably fine) for the camera because the focal point is pretty far behind the scope.

20 minutes ago, Astro_Nic said:

Sorry your scope isn't perfect....makes me think maybe it does need some extra support....but £450 for a piece of steel? 

Its a minor inconvenience at best  and only because i image with mine. The VX series is not meant to be perfect, its meant to be nice optics in a good enough package around them. Very appropriately priced in my opinion.

Edit: not the extra bit that is, i wouldnt dream of paying that much for a support piece.

I have the VX8, also an aluminum tube. I dont know if people are not entirely honest, if it doesnt affect visual, or i got a weaker than average model but the tube is by far the weakest part of the VX series.

Mine is (and always was) noticeably not round. The secondary mirror supports are very weak and have to be tightened quite a bit to be stable. They are tight and it is stable, end of story? Not quite, they have dented the front into a square shape. The rear is aldo dented to a triangular shape because of the 3 point attachment of the mirror cell to the tube walls. The denting means diffraction spikes are not symmetrical because the tube is not round, but other than that just cosmetic damage.

For what its worth i have never noticed these in visual use.

1 hour ago, AstroMuni said:

It should take the same amount of space as when doing via Siril directly. After all it creates a script which then executes in Siril. You can configure it to do processing in 16bit as that would help.

It does take the same amount, i have hundreds or thousands of 50mb files per stack. Doing background extraction and cosmetic correction (not sure if necessary) will add another set of subs to be saved when stacking. Of course i can use DSS which is less hungry in terms of space but the results are worse.

I dont think 16bit is enough, i am shooting short exposures and the difference in background and signal can be only 0.1 ADUs in the 32bit stack. This would drown in noise with 16bit, unless i am completely wrong on how it works.

For a comparison, the 550D on raw video movie crop mode will write at 21mb/s regardless of card (camera limitation), so i would assume your write speed is good enough.

51 minutes ago, parallaxerr said:

Excellent, thanks Geoff! So that's 17.5MB/s transfer rate, something solid to work with.

If I extrapolate out your quoted resolution vs what I intend to run with my intended camera, I get 280MB/s @130FPS.

I do wonder why you have the need for increased resolution if this is the limiting factor? ADC bitrate also plays a large part in file size, you can lower this in many cameras to increase framerates. 

Really what concerns me is the capabilities of the laptop, it might not be able to handle high framerate video of really any resolution.

1 hour ago, nfotis said:

Had ordered a laser pointer via Ebay, but it doesn't operate when I installed fresh batteries in it (I suppose that a 5 USD price was too good to be true...).

This looks exactly like these: https://www.amazon.com/3Pcs-Interactive-Cat-Kitten-Dogs/dp/B09228WSL8/ref=sr_1_1

 

Any suggestions? I am thinking about outreach mostly (to show constellations etc to others)

N.F.

 

Cheap laser pointers like this are an extreme eye-hazard, be VERY careful when using laser pointers from sketchy sources!

Very often these no-brand chinese lasers are nowhere near their rated safe(ish) power of 1-5mW and instead can be in the 50-100mW range. These are built to such a low price that there is probably no quality assurance of any kind. A typical 5mW laser pointer is still dangerous, mind you but not the instant irreparable eye-damage levels of the more powerful ones. Not a thing i would personally want to save any money on.

If this ToupTek manufactured camera follows the same logic as my RisingCam (ToupTek manufactured) the conversion factor would be a factor of 100. My model goes from 1-100 in ASCOM and 100-10 000 in the ToupTek driver.

The 1-100 ASCOM value corresdponds directly to the relative gain value (not db).

Whether it was necessary or not to play with rice, all the gear appears to work as intended. The wire going from my power supply to the integrated cooling fan on the VX8 mirror assembly had blown a fuse but works after a new one, but other than that everything appears undamaged. Really quite surprised the PC boots up as i saw water dripping directly inside the case, and where i assume the motherboard to be. Opened up the case a bit to maybe improve air circulation (put it in front of a fan for a while) so i don't think anything is damaged.

8 hours ago, The Lazy Astronomer said:

Actually, I think it does work (in that rice will absorb moisture), albeit not that well, so really it should really be thought of as a poor man's dessicant sachet.

Speaking of desiccant sachets, buying some reusable silica gel and putting moist electronics in a box with it might be a good idea in the future if the weather forecast  when the weather forecast does a 180 suddenly.

2 hours ago, Xiga said:

How do people find StarXterminator's handling of Newtonian diffraction spikes? 

Only just recently started experimenting with starnet and StarXterminator but i would slightly favour the latter with my tries so far.

Bright stars still have spikes, especially if the star is close to any nebulosity, but it looks like there are fewer remaining artifacts compared to starnet++.

1 hour ago, waroffice said:

The rice thing is a myth by the way, it doesn't do anything

Care to link somewhere that explains this?

Not for many years. No reason to upgrade from WIN10 and there are no guarantees the new version is any better. In my opinion the first few years after a new OS gets released is just unofficial beta testing from early adopters. Im in no rush as WIN10 will still be supported for 4 years.

Also, the strangely strict hardware limitations will turn just about 90% of the existing desktop PC crowd away from the upgrade, including me. In 4 years i might retire my I7 6700K/GTX1080 combo, which is still top tier stuff after years of use. I find that hardware hasn't really improved all that much in the recent years, so why upgrade?

15 hours ago, MHaneferd said:

Thanks again. I’ll buy two strips to be at safer side and just see. Hopefully it manage the winter here..

For me here, last winter was easier in terms of dew than current conditions. Relative humidity of 99% in -20 is still less water in the air than a humidity of 50% at +10. It will work out great.

1 hour ago, Chefgage said:

Avoid the rice idea, bit of a myth type thing anyway. A nice warm room will be better. The thing with rice is you risk getting small particles/rice dust onto your optics.

Im not worried abot the telescope, being a newtonian its exposed to weather, dew and frost all the time. My mini-pc is what took a beating there, being made for normal inside use it is not designed to be in rained on.

Ill have to come up with some sort of shield on it to prevent this kind of thing again.

1 hour ago, Alien 13 said:

No astro gear I know of is designed to be waterproof weatherproof but perhaps damp proof so its best to dry each item as best you can and leave then somewhere warm and dry, sensitive electronics can be placed in a container of uncooked rice if its realy wet.

Alan

Yeah, the mini-pc might have died as it rained directly inside it through the vent holes on top 😭. My tube orientation was such that the camera and the various usb and power ports were also exposed to rain for a bit...

Well ill throw them in a rice bath and hope they didn't mind an unscheduled wash.

As the title suggests, i got caught mid imaging with a quick but strong shower. It took me a while to pull all electronics out and cover the scope.

Is astro imaging gear sensitive to rain, and if so whats the next step?

A simple usb powered dew heater kept my guidescope clear at -20 last winter. Everything else was covered in frost though.

There is probably a "release shutter without lens" option in the settings that you have to enable. 

Thought i would report that i am experiencing something pretty much exactly like this, a colour gradient across the image.

Started noticing this after changing my usual imaging spot of B6-7 to a 6, maybe 5 on the best of days. On the new imaging spot there is an extreme gradient as most targets just skim the edge of a B8 light dome.

Also, there is a baader UV/IR cut filter in front of my camera. 

I am wrestling with IFN at the moment and there is a fine line between fixing the gradient and nuking the nebulosity, but so far has worked out.

10 minutes ago, Dazzyt66 said:

it usually works by the time I get to 100 - I don't think I've ever gone over 200 with it as it washes stuff out.

This sounds like the complete opposite of me. I always crank it all the way right, to 1000. Still the image looks mostly black with some of the brighter stars visible. Probably because all of my signal is within the first 200ADUs or so.

1 hour ago, Tiny Clanger said:

As condensation occurs when moist air comes into contact with a surface that is good at conducting heat (like glass or steel) , I'd guess that flocking would act as an insulating layer, and actually decrease the chances of the sides of the secondary dewing up . As the back of the secondary is facing space, and losing heat , it is going to be colder, and more prone to dew than the front of the secondary.

Heather

Didnt think about that at all. The flocking material is the exact opposite of a reflective glass mirror, so will probably be dryer than any metal/glass parts. Radiation of heat will probably have a lesser effect too when the insides are completely flocked all the way to the top of a dew shield.

1 hour ago, Nyctimene said:

Painting the secondary edge with a black felt tip or paint will still leave some reflexivity, esp. when light hits the mirror under grazing angles. I preferred to flock the secondary's edge (only half of it's circumference can be seen from the focuser) with self-adhesive velour flocking material (D-C-Fix here in Germany). Working in small pieces, I started with making a trapezoidal paper template for the part of the secondary, that points directly at the sky ( - the region of the major axis' exit) and cut it with fine scissors to the correct size and shape. I then transferred the template's outlines with a fine pencil on the velour's paper side, and cut out the part. A small pincette was used to put it into place. The same somewhat fiddly procedure followed with four more pieces (but you have to measure and cut only two templates, that are used back-to-front). The result is shown here with my Skywatcher Heritage 130 P Flextube:

You don't have to work with extreme precision - the main point is just to get most of the stray light absorbed.

Stephan

This looks pretty nice too. I do wonder whether the fibers would attract dew/frost and just bring it closer to the mirror. The backside of my secondary is sometimes wet/frozen, but so far the mirror side has been mostly dry.

I have 2 rolls of flocking and some paint coming soon so plenty of extra material to test and play with.