Thalestris24

Most stars aren't exactly black bodies cf spectrometry. I feel the pursuit of some sort of 'accurate' colour rendering in astrophotography is a neverending minefield - perhaps akin to a Mandelbrot Set!! Don't forget to take into account atmospheric extinction, monitor calibration, ambient light, and what your eyes actually see (how are you going to know for sure?). Surely a simple, approximately accurate but satisfying, pretty, coloured picture will do the job? Will anybody really care that much otherwise? Me, I mostly stick to monochrome/luminance these days - so much easier, especially when life is so short! Louise

I'm afraid mine's been put to one side for the moment. Louise

Hi again LOL221 You may also find this thread of interest Louise

Hi LOL221 The multispectral filter you mentioned would do if that's the only one you can get to fit your camera. I don't have a Nikon but I think I've seen clip filters for them - Astronomik, STC? However, I think you'll struggle with your alt-az setup. You're going to be limited to ~30s exposures. I think you'll have to take a lot of 30s exposures... Do post some of your images Louise

Oh ok - sorry, I should have read it more carefully...

I got this from the apt forum "If Settings->CCD->Manage Gain is unchecked APT will not touch the gain value and will leave the ASCOM driver to take care. If the option is checked then APT will use the gain values in Settings->Filter Wheel and Camera tab if they are not empty and if the ASCOM driver accepts setting gain value from APT." So looks like it's normally set in the Ascom driver

But maybe the ambient temperature dropped rapidly? If it's a biggish triplet it can still take a while to stabilise. Louise ps this is just an idea - I don't have any great expertise 🙂

Hi Have you got the 'manage gain' option checked under settings->ccd ?

Looks a bit like thermals to me - was the scope temperature stabilised? Louise

Some lovely and recent images of Jupiter from Juno Mission: https://www.space.com/stunning-image-of-jupiter-from-nasa-juno.html?fbclid=IwAR3OJ3gln5LPVzZHbN1c8r6_ivt4f0z97dJi9LAyEzdoIbAZtc2Ainv7fvU Louise

Unfortunately, it hasn't affected the cloud 😞 Sigh. Louise

Doubtful, unfortunately, but can enjoy the lower air pollution here in the city, while it lasts! Louise

I noticed that the floodlit sports complex near me turned the lights off early. When I checked it out online it closed at 8pm until further notice. As it normally lights up the sky for miles around from dusk until around 10:30pm, it's a positive side effect for me, arising from the current anti Covid-19 measures. Perhaps other people are also experiencing some positive side effects? Louise

FWIW, I aimed to get my spacing to align close to the mid-point of where the focuser puts the lens. That gave me focusing leeway. Of course, it all changed when I swapped my camera... Louise

Maybe not far off focus. The focal length is determined by the Lowspec camera lens. I got mine close to focus by measuring from the lens to the sensor plane to get the right T2 tubes between the camera and the Lowspec body. I've not found my Lowspec focuser easy to use - my one tends to be a bit stiff 😞 Oh, I added a rotator to get the camera sensor horizontal. Louise

Ok, so, if I got one, I would just connect it back to front from normal. Not sure when/if I'll get one as Western Europe is shutting down at the moment 😞 Ta! Louise

Hi Ken I just re-read your reply and bit unsure now. Would the Vixen flip mirror let me select inputs i.e. the telescope or the calibration source? So the flip mirror would be connected to the scope and lowspec T2 scope connector? I was a bit confused by the mention of 'guide port' as that's separate and 'standalone'? Cheers Louise

Yes! I wanted to easily be able to use the nitrogen spectrum lamp. I thought the Vixen version might be reversible but wasn't sure. Thanks! Louise

Anyone know if there's a cheaper equivalent of the Baader Flip Mirror II to work with a spectrograph i.e. handles two inputs rather than just two outputs. Thanks for any input Louise

Yep. Don't worry, with a bit of practice you'll be fine. Once you have focus on a star or the Moon, you probably won't have to focus again. Good luck Louise

The camera is very sensitive. Focus can be difficult to find. So best set up during the day with qhy's EZPlanet software. You need a very short exposure - perhaps just a few ms, you have to adjust the exposure so it's nether a bright white field or a pitch black one. Once you have a reasonable exposure then you can try and focus on a distant object e.g. a pylon or church spire that is several km away. The focus point is quite critical. Louise

What scope have you attached it to? It helps to use a very short exposure and focus during the day on a distant object. Louise

Had the nitrogen spectrum tube running. I connected it up to a '400kV' 'Step-Up Boost Power Module' I got off Ebay. Input voltage was from a 12V battery via a variable DC-DC converter. The Boost module is supposed to run from a 18650 4.2V battery but I don't have anything that will properly control the 18650 voltage. Anyway, are a couple of YouTube videos I made: 1. Using a minimum voltage from the DC-DC converter: 2. Using a slightly higher input voltage: Now I just need to get the Lowspec up and running again (I still have a problem with the guide platform 😞 I've reprinted it yet again but need to tap the holes and clean it up in order to get all the parts to fit together. Louise

Well the EL Panel inverter powers the little EL panel I bought 🙂 It does just power the starter bulb but maybe not quite bright enough. I'm not sure whether that's a current limitation or a voltage one. The inverter can also give an electric shock... 😛 Panel: Starter Bulb: As I have two of the EL inverters, I might try connecting them in parallel to see if it's a current problem. On the other hand, at 120V the bimetallic contacts don't switch on and off. I'll try out the EHT source plus a power controller with the nitrogen spectrum tube tomorrow. I know the EHT source outputs a very high voltage... Louise

If you can find the data sheet for the particular starter bulb you have it will quote a non-reclosure voltage. For a Philips S10 'Ecoclick' 4-65W that voltage is 140V. So below that it shouldn't close the bimetallic contacts. I've bought a couple of EL power supplies which output 120V. I was hoping to use them without a resistor. However, I've not got around to trying them yet - they were very cheap so no great loss if they don't work. I also bought a white EL panel to maybe use for flats. I've also bought a nitrogen spectrum tube which might be better than a starter bulb as it has a limited spectrum but covers the visible range. I haven't got it working yet - I have to sort out a power supply that works. I think the tube needs around 2kV to strike. I have some power supplies (CCFL) and an alternative EHT one to try. Hopefully, will get around to trying them out soon 🙂. Louise