ONIKKINEN

9 minutes ago, Jonk said:

I thought exactly the same, a good run of clear nights at the worst time of the year for astro-darkness.

But, there's plenty to observe / image in the summer, even with the very short nights, it's not all about long exposure DSOs.

True, Planets and the Moon i did manage to see/image during summer. Jupiter was surprisingly good on one night (just that night) during summer so not entirely wasted.

As someone living at 60 degrees north, i have 4 months offseason every year at 2 months either side of midsummer. Looks like the summer months were not that bad, is there any astronomical darkness at that time of year for you?

As a bad joke, we too have most of our clear nights during summer in which astronomical darkness is physically impossible...

On 31/12/2021 at 21:14, ollypenrice said:

My imaging rig priority order is, without any doubt whatever, mount-camera-optics.

Olly

I ignored the mount part when building my setup and hate myself for it. I thought "well the manufacturer says 10kg is fine so why would a 0.1kg telescope be any better than a 9.9kg one". Well its not that simple and that's the markets fault for accepting the blatant lies from manufacturers. We really do need manufacturers to state AT WHAT FORM do the payload limits and FOR WHAT USAGE they apply. For imaging and for long OTAs, like long refractors and especially Newtonians the limits are probably closer to 50% of the stated "max payload". Shame it has to be this way really as i believe the overwhelming majority of the userbase is budget limited and must choose which evils to pick from, and the mount should absolutely not be one of them.

If i had a time machine i would go back in time and pour almost all of my budget in the mount. Nothing else in the setup matters at all if the mount underperforms.

18 minutes ago, alacant said:

So, plug and socket on each;)

In this game, especially at 03:00 when you're half asleep and the dew has had chance to work its magic, you need the fewest possible bits to check. Believe me!

Cheers

Thats why i go to sleep at 05:00

But yeah, less things to break is generally better for reliability. I used to be a car mechanic and my favourite vehicle was the Suzuki PV (a moped). Do you know why?

There are basically 2 cables in the entire vehicle that go to 3 places. 1 connection to the rear light and 1 to the switch to control low beam/high beam and from there to the front light (no other electric appliances). Either the alternator is broken, the light bulb is burnt or the cable is disconnected somewhere so very easy to fix 😂.

A customer bringing in a car that sometimes has an electrical problem with nothing in the diagnostic computer is a NIGHTMARE. Never doing that again unless forced.

25 minutes ago, alacant said:

We connect via eqmod, sometimes remotely. Quite often I'm the guy on the ground at the telescope end...

Speaking from bitter experience, they're cheap items and for us at least,  replacing three pieces of hardware (eight mating surfaces to go wrong) with just a single cable makes for far fewer sleepless nights!

Cheers

8 surfaces?

HC to cable, cable to mount, HC to USB-cable, USB-cable to PC. 4 connections?

But i do understand in that case. If you cannot physically access the setup the thing with least possible points of failure would probably be desirable. But also i cant really see how the HC somehow unplugs itself with the self locking connectors, but i dont have to care for unattended mounts so it could happen for all i know.

6 minutes ago, malc-c said:

It was noted in a recent post on the EQMOD user group then when the handset is connected to the mount that has a USB port, and a USB cable is also used between the handset / mount, it's easy to end up screwing up the positioning (such as goto) when driving the mount via the PC if the handset is first used to polar align / or any function that requires the mount to move as EQMOD loses positioning data and then has no means of knowing the true position of the scope.  IMO it is therefor better to use either just the handset for control and remove the PC connection, or if PC control of any sort is used (plate solving / guiding / alignment etc) then just use the PC and associated applications to do so.  This way each application knows where the mount is pointing as they all communicate via ASCOM / INDI.

If EQMOD is used with the USB plugged to the mount but not the HC, the HC must not be used as the HC and EQMOD do not communicate directly and yes you do lose positioning information. But the idea of using the USB to HC connection is to not have to use EQMOD as it is not necessary (IMO, dont shoot me). USB to HC connection means EQMOD does not work. So in this way yes it is correct that the worst possible way is to use a USB cable plugged to the mount and running EQMOD but still doing GO-TO/slewing with the HC. In that case you must ditch the HC as it is nothing but trouble.

With USB to HC connection you do not, and can not use EQMOD. But both the HC and PC are fully aware at all times of the position the mount is in. You cannot slew in one with the other being out of touch and losing the position. I can slew to M51 with the HC and NINA agrees of the coordinates. Likewise i can do it the other way around, slew in NINA and the show position utility function confirms the coordinates as M51's coordinates.

19 minutes ago, alacant said:

Perhaps the main disadvantage is that one still needs the hand controller in the mix.

Depends on the user. For me it is an advantage as i do not have to use stellarium or CdC with a remote desktop connected tablet (pain in the backside) and can do some things with the HC. For people who can abandon their setup overnight running in their backyard and do everything remotely with a proper PC, maybe a disadvantage as it is one more trinket to connect and carry outside. But also why buy an extra Serial chipped cable when the handset will act as one? Some like, some do not.

20 minutes ago, alacant said:

Is it possible to use EQmOD without PC-Direct?

Not through the HC. Without? Its a tricky question since you have no way to set PC-direct mode without the HC so i think the answer is no you cannot.

1 hour ago, alacant said:

1. USB cable from PC to hand controller (HC). The hand controller runs normally, you do polar alignment and 3-star alignment from the hand controller. Kstars/Stellarium/cartes du ciel etc can send commands to the mount to tell it where to go. AFAICT, on-camera  st-4 guiding (phone cord from camera to mount) is the only way of guiding with this configuration.

2. USB cable from PC to HC, just like (1),but set the HC to PC-DIRECT. You no longer need to do a 3-star alignment from the HC. Install INDI or  ASCOM on your PC. It allows the PC to take the place of the HC. This makes things like plate solving possible, which greatly simplifies life (once you get plate solving configured and working). on-camera or pulse guiding are possible, the former being preferred. It also eliminates the need of that phone cord from camera to mount. Anything for fewer cables;)

1) HC does work normally, but wasting time with star alignment is not necessary. Also ST-4 guiding is not necessary. Full PHD2 pulse guiding works just as well. The USB port in the HC is a Serial to USB chip in disguise as a normal USB port, which is why the prolific drivers are needed. You have full control of all mount features with both the HC and the PC this way. Both can initiate GO-TOs, slew manually etc.

2) PC-direct mode is only used for certain types of firmware updates and never in "daily use" like this.

This only applies for the latest version of Synscan where both the HC and mount have USB-ports somewhere, but this version has been sold at least since 2018 so most units are like this. I believe method 1 is the ideal way as you do not need to buy the extra Serial to USB cable and still have all features available.

Live video coverage with decent cameras and multiple angles is a fairly recent thing from SpaceX i think. Since they are a commercial launch company they literally make their money on public relations, like pretty videos from space.

JWST has been in development for longer than the concept of HD-video has been available (not kidding!) so this was probably not even considered in the design phase. Obviously they could add cameras later but this just adds complexity, mass and has no real mission benefit. Im sure there is a sensor for everything that could go wrong already in place and a camera would just be redundant. Also i think JWST is such a big thing now because it has been delayed for an eternity. Had it launched in 2018 as intended i dont think there would have been such a fanfare surrounding this and the public coverage would have been a lot smaller.

2 hours ago, BuUsef said:

Hello everyone,

How is your experience with the eqm35 going? Unfortunately there isn't much information shared about it online.

Do you think it can handle 6" SCT with asi294mm pro?

How long exposures do you get?

Please dont do this! Terrible mount, lots of unfixable issues. Some people claim pretend their mount works OK, but i suspect that is due to a) not wanting to admit to yourself that the money was spent wrong, b) using a very lightweight and forgiving setup, like an 80mm refractor and so just not being aware of the issues.

Its just a tiny bit cheaper than the EQ5 but much closer in comparison to the EQ-3 which is in a class of terrible on its own. If you plan on shooting unguided you could probably get 5s exposures to be consistently decent but not much longer than that. Guided performance depends a lot on the mount in question as these apparently have quality control issues, and also on which part of the sky you point at. Closer to the poles you can get decent performance because the sky moves slow. Closer to the celestial equator you will not be getting the performance you are looking for. But the EQ5 costs the same and does everything better.

Since you already have a proper astronomy camera in the form of the 294MM that costs a fair bit of money, why not spend money on the most important part of the setup: The mount. The telescope and camera are second after the mount that drives them. If the mount underperforms your telescope and camera are basically wasted away to poorly tracked shots. I would recommend staying away from this price class of mounts and getting an HEQ-5 or better for astrophotography.

Sorry for the rant, i feel strongly about this as i made the same mistakes as a beginner buying equipment. Oh, and welcome to SGL!

24 minutes ago, StevieDvd said:

Sounds like the co-ordinate system between the platesolve and NINA/APT could be set differently J2000 or JNOW (or one is metric the other imperial 😗)

Not my area but just applying simple logic.

Actually think you might be correct. NINA sometimes gives a notification that goes something along the lines of: Mount coordinate system B1950 was converted to J2000, or something like that. Cant remember exactly how the error went but i have definitely seen this one.

B1950 is also an old sky coordinate system, could be that Skywatcher mounts follow this system for some reason?

1 hour ago, david_taurus83 said:

Thanks for this. I will look into it. Just to be clear, is this the Skywatcher Synscan Pro app in Windows you use or just a widget that pops up like Eqmod?

Eqmod usually doesn't sync platesolved coords for me despite NINA getting a target bang on centre. It's not bothered me too much but I always wonder if this is why I have struggled with meridian flips. Both my first and current AZEQ6 always rejected syncing.

Its not the app, its just a tiny 100px widget that has the directional keys. Never used that either actually.

Im not sure my platesolve syncs work since there is no error message telling me that they were rejected. ASTAP always finds the target after 1 re-slew but to hit my tolerance of 30arcsec will take several retries. After a GO-TO to another part of the sky it will again be about 2 degrees off on the first one, so i think mine rejects the sync too but EQMOD is not there telling me about that.

42 minutes ago, malc-c said:

In addition to the info Steve posted above, the issue with Prolific drivers required for most (if not all) Skywatcher mounts with USB connectivity is that when Microsoft was developing windows 10 Prolific did not want to comply with the licencing agreement to have their drivers included as standard with windows 10 installation.  So Microsoft didn't include them as a native driver in its build.  Hence why 3rd party devices the use the chipset for USB to TTL serial (PL2302 normally) such as Skywatcher provide the last know version (normally windows 7) of the driver on their sites.

This might explain why my desktop PC recognized my handset as COM4 as soon as i plugged it in the first time but my mini-pc did not and had to install the drivers manually.

44 minutes ago, malc-c said:

Well that's interesting....   Just spent a while doing a test.  It look longer than I thought as the graphics card in the observatory PC was playing up (it's not been used for some time) but anyway I downloaded NINA, installed and launched the application.  I hadn't configured anything and prior to this had restored the machine back to a pre NINA config after the previous time it was installed, so no previous settings from the last time I messed about with NINA existed on the PC.

I selected the Telescope section, it had HEQ5 displayed in the options... clicked Connect and it launched EQMOD.  !!!!!!!

EQMOD still works with USB only control, but doesn't have to be used. I think it was a "skywatcher mount" or similar option in NINA that does not launch EQMOD.

1 hour ago, david_taurus83 said:

That's interesting. So you don't use Eqmod at all? It doesn't get called up when you connect the mount? 

No EQMOD at all, correct. There is a small skywatcher widget on desktop after connecting though. It has N/S, E/W and slew speed buttons and nothing more.

But its not necessary since NINA and PHD2 (and the handcontroller) have full control of the mount.

15 minutes ago, Ags said:

Desturation. I like it, sounds very Star Trek. I suppose it means spinning faster and faster with no way to slow down ( without making JWST spin in the opposite direction)?

Yes, and the wheels can be allowed to spin only so fast without risk of damage. At some point all the wheels are spinning so fast that any changes in orientation take ages to do and they must be de-spun to maintain control. If you just let the wheels de-spin unpowered JWST would be doing cartwheels as the force has to go somewhere, which is why some form of external torque is needed (usually reaction control thrusters).

Sensitivity is the same with all ISO settings. How much the captured light is "boosted" and how bright it is interpreted in the image will change, but you cannot change the sensitivity.

29 minutes ago, kirkster501 said:

The positioning itself is still done by small thrusts of rocket engine lighting.  The gyroscopes - and these are much more reliable than the HST's -  provide the reference for a 3-D model of the sky that is constantly calibrated by the alignment of Canopus and Vega.  What the JWST team do not want to be doing is slewing all over the sky between research projects. i.e M82 and then M42 and then M87, for example.  The projects are scheduled scope time dependent on proximity to each other in the sky as a major factor, amongst some other things, to minimise fuel consumption.

Isnt it reaction wheels doing the fine pointing and gyroscopes "guiding" or making sure the orientation is correct?

Reaction wheels saturate if left running and need to be de-spun with external forces. Propellant is used for this most of the time, but the HST uses magnetorquers that somehow utilize the Earths magnetic field to provide the de-spin torque (no idea how). I guess L2 is far enough out that its not an option?

Also, light pressure will probably be considerable since JWST is basically a sail with the fully extended bits so reaction wheels probably need more desaturation.

1 hour ago, scotty38 said:

I actually used that on my old laptop along with all the other stuff. On this new pc I didn't install it and, as far as I can tell, NINA and everything else works exactly the same as it used to do but who knows what gremlin awaits....

 

Don't know if it's relevant but the SW prolific driver is from 2018, I guess it's possible the other stuff has moved on?????

Well i sure hope the whole serial faff is left behind soon. Would believe it if the driver was from 2008 as i dont remember the last time serial cables were really a thing outside mounts...

3 minutes ago, Stu said:

Isn’t that the point, it has a certain lifetime governed by the amount of fuel available for the course corrections required to keep it in orbit around the L2 point? It is not a stable orbit so needs to be maintained.

The good thing is that they have more fuel than they hoped, so the lifetime (assuming everything goes smoothly from here) should be longer than 10 years.

Yes, some lagrange points are not very stable and need regular maintenance to stay there. Which is why we dont see L2 orbiting asteroids.

L4 and L5 are stable though and in the case of Jupiter-Sun Lagrange points are full of asteroids in the form of Trojans and Greeks.

5 hours ago, Rusted said:

Thanks. Unfortunately Brexit has made it all but impossible to deal with the UK from the EU.
Even with forward VAT payment we recently ended up paying £40 extra on top of our £60 purchase + £25 for delivery.

I find this to be not true for many products. Small purchases probably not worth it but FLOs pricing is very aggressive for many other products.

Recent example: Astroshop sold Pentax XW series eyepieces at 369e and then had a "sale" for 369e from 399e. Thing is they were 399e for no time at all or just a while for legal purposes. Meanwhile the same sale over on FLO was an actual 20% off sale and cost me 280e including 24% VAT and 4,2% customs for telescopes and their parts and delivery on top. Many other products are also competitively priced, like mounts where the extra delivery cost sinks easily to the price of the product.

Yes dealing with customs is annoying and takes time but everything is out of stock everywhere anyway so rarely matters.

You need to download and install the prolific USB to serial drivers from Skywatcher even with the USB cable.

By the way EQMOD is not necessary then. At least NINA works with the native skywatcher driver just fine.

The left-right axis in all graphs here is the Gain value. Gain is like ISO for normal cameras, increasing the value will make the image brighter.

Top graph is full well depth of a pixel in electrons. The 533 has a fullwell of 50 000 electrons at the minimum gain value. Electrons are created when light hits the sensor so the camera measures these in the form of voltage instead of measuring photons directly.

Second graph is the relation of gain to e(lectrons)/ADU. ADU is the pixel value. This one being a 14 bit camera will record values between 0 and 16384. Different gain values change how many electrons does it take to gain ADUs. The marked spot of gain 100 has a 1e/ADU gain so every electron results in 1 ADU increase of a pixel value.

Third graph is dynamic range in stops. Mostly irrelevant for astrophotography, but this camera has a very high DR. Dynamic range is the difference between read noise and full well depth.

Fourth graph is read noise in electrons and is the most important graph to look at in this case. Notice that at gain 100 the read noise drops dramatically, but does not really decrease all that much after. With this particular camera a gain value of 100 is the best for almost all applications. Read noise is noise created by the camera every time an exposure is read from the sensor, so this is the same for a 3s and 300s exposure. Read noise of 1.5e is very low and allows short exposures to be completely sky noise (light pollution etc) limited.

Take away from this: Gain 100 is the best for thia model.

13 hours ago, Gonariu said:

In fact, with the temperatures you have in Finland in the cold season, you need to have a lot of courage to go outside. If there are + 3° outside at Orotelli I do not have the courage to take out the telescope or I make a hit and run observation (I must say that I have a slight chronic pharyngitis that does not encourage me to go out on too cold nights, at least according to the concept of "cold" that we have here in Sardinia). In Cagliari which is on the sea and has a subtropical climate "I dare" more .....

Its not that bad if i just wear proper layered clothing. 1 or 2 base layers of merino wool and then whatever on top of that + a ski jacket is already good enough for down to -20 for a while. It will still be cold though if im standing still at the eyepiece, but a short hop into somewhere warm for a while or do some jumping jacks and its warm again 👍.

Mine would be a good power station, this one: https://ecoflow.com/products/ecoflow-river-portable-power-station

I had a smaller celestron battery pack and a car battery jumper pack at first and it was never really reliable for long and dropped below 12V faster than i expected. Also had a 12V cable going out of my car door with the engine running when it was very cold outside 😆. Buying this power station just made all the problems go away in an instant. Has never run out mid session or dropped to voltages low enough to cause problems as it is regulated. Well worth the mone and a true worry free replacement for all the possible ways you could power a full photography rig 👍.

I would point out a few things that came to mind. How quickly do you want to get results? What types of targets do you have in mind? How much do you want to tinker or "lose time" with the setup?

I image with a 200mm newtonian and a poor quality mount and its been mostly trouble the whole time, so i would advice against that. Newtonian with a good mount? Dont know, as i do not have a good mount yet but im hoping my upcoming AZ-EQ6 will be up to the task. But here's the thing: I want to image galaxies, most of which are dim and smaller than nebulae, do not benefit from light pollution blocking filters, and i want to do this kind of imaging quickly as i cannot control the weather. I am also not made of money so a newtonian was really the only option for me. Large aperture compared to price and a very convenient focal length that is not too large really fits my use case perfectly.

But if i had more money i would definitely want an APO in the 130mm and up range to do the same job. Also, if you are already considering the HEQ-5 which is a fair bit of money why not go for the bigger EQ6R-PRO? I really do hate my mount and wish that nobody would try to undermount their telescopes so if i had a time machine i would put almost all of my budget into the mount.

13 minutes ago, Swillis said:

From what I understand ISO shouldn't matter for signal(?) As it effectively multiplies the signal, same number of photons reaching the detector. But also read noise goes down at higher ISO?  So we should use highest possible ISO

Thats pretty much it, but with a few caveats. Read noise goes down as ISO increases, but for most models only to a point. Once at that point there is little to gain from pumping up the ISO, but there is detail to lose in the form of overexposed pixels. Fully saturated pixels no longer contain useful information so this should be avoided, if possible.

Where this sweet spot lies depends on the model of camera in question, but according to some sources the 350D sweet spot would be at around ISO400. For my 550D it is around 800 and that's what i used for all shots when using the camera. http://dslr-astrophotography.com/iso-values-canon-cameras/    https://astrophotography.app/EOS.php