teoria_del_big_bang

The celestron 7Ah will certainly not run all your gear for any meaningful length of time.

There are so many threads on SGL alone about remote site supplies so well worth a search on here.
It is also a tricky subject and one that does not come cheap (well not very cheap).

By the sounds of it you only need 12V and not 5V as well (many need 5V for their RPi if running Astroberry, or Stellarmate etc on a Rpi) which makes things easier.
Also when people need to power a laptop as well also becomes more difficult as they normally need around 19V and also consume a fair bit of power, but I assume you are using your phone or tablet maybe to communicate with Asair ???

With what you have listed I am assuming the following: 
ZWO focus motor - may take around 1A
2 dew heaters (8” Astrozap and 3” Lynx) - probably around 1.5 A between them maximum
ZWO Vonet wifi extender - It says typically 5V at 2A but I would be surprised if more than 1A
ASIAIR Pro - normally a RPi is 5V 3A but this runs on 12V so I would guess will take around 2A.
EQ6-R - Requirement is 4A but again probably will not take much over 2 to 3A and then only whilst slewing to target, when tracking probably more like 0.5 to 1A.

Now a lot of assumptions because difficult to determine the actual power needed without actually measuring consumption current. Focus motor in essence will take practically nothing when not focussing and that does't happen all the session, mount only takes a high current when slewing to target, and again this doesn't normally happen often, but some nights may be more than others, dew heaters, Asair and wifi extender will be fairly constant but difficult to say exactly how much they will take.

So a very round about guess is you will take around an average of 5A for your setup.
So 5A at 12V is 60 Watts (Watts = power).
So for a 4 hour session you need a 12V capable of 4 x 60 = 240 W h (Watt Hours). Which is actually a fair bit of power. Again I may have well over estimated this and you would have to measure the current drawn but is going to be between 3 and 5A average I am sure. (After I wrote this I see you said around 3A measured when tracking - so for safety say 4A average)

So if it is 12V only at 4A you basically have a few choices. Each has their advantages and draw backs.

1.  Some form of 12V leisure like battery set into a box with connectors to suit your requirements.  Advantage is that this is probably the cheapest option, disadvantage is they are heavy and need looking after. You cannot run them right down otherwise they will not recharge properly and will be permanently damaged. So you need a supply capable of a higher Wh than needed and you must keep them charged so when not in use you need to get them out and charge them say once a month or leave on trickle charge. So something like This Battery Box , This battery and a Charger
2. You can buy a car jump starter pack similar to This . This is just a lead acid type batter with some jump leads and in essence similar to option but a smaller battery and will come with a trickle charger. So same issues with it needing kept charged and often difficult to determine what the Wh actually is as many give misleading specifications stating only the maximum current they deliver. Some are only 7.2 Ah batteries and most will be no more than 20Wh. So I do not recommend this option, but many do use these or some form of them that are not necessarily made to start cars with dead batteries such as This  but at 17 Ah you cannot get all that 17Ah out of it without damaging it so say 12Ah is may last you 3 at 4A hours but I would say count on 3 hours not 4. 
3. A lithium power pack. Much lighter than the leisure battery option, also no issues with damaging them with leaving discharged and can use the full available powr without damaging them. Disadvantages are the price as these are not cheap. This is a good one. and although only 13.2 Ah (less than the 17Ah above) you should get all of that if fully charged so would get a similar time out of it to the one above at 3 to 4 hours. But as £260 is a major investment.

If on a budget I would suggest maybe the celestron 17 Ah powertank and then use your 7 Ah Powertank as well. Run your mount from the smaller one and the rest from the bigger one. You should get a good 4 hours from them, maybe a bit more, just be careful with making sure you do not drain them fully in a session and then keep them topped up when at home.

Steve

2 minutes ago, StuartT said:

sorry, supplementary question.. most people seem to shoot video and stack the frames (rather than shot individual RAW files like I've been doing so far). So is it possible to do that with a DSLR also? i.e. use canon's native video format in something like Deep Sky Stacker?

 

For DSO images I have always used stacked still frames, even on DSLR.

Stacking video is more for planetary and lunar imaging I think,

Steve

15 minutes ago, iapa said:

This was from Modded 600D, 50mm f.14 lens

Mount would have been Celestron AVX.

Over at least 3 nights I expect.

110 x 120s @ ISO 800

38 x 60s @ ISO 800

22 x 30s @ ISO 800

Yes well I think @alacant has demonstrated the data is good data and capable of bringing more out of the galaxies without bloating the stars.
Which is why I was sort of saying take my thoughts with a pinch of salt as this is why peoples experience in processing is so important and like many I am still learning all this 🙂 

Steve

@alacant Wow,that image does have a fair bit of detail in the galaxies and nice looking stars, so I was wrong it was not a lack of data in the subs but all in the processing. 🙂 

Steve

On 02/05/2021 at 09:25, Dean Hale said:

Arrived yesterday however i was at the Pub after a long absence. ASIAIR dovetail clamp and a power cable. The clamp is well made but i feel a tad overpriced by ZWO. 

22 hours ago, callisto said:

Snap!..I got the power cable earlier this week...you can't go wrong with Lynx products 

21 hours ago, Dean Hale said:

Yes it's really nice product, so nice i'm going to buy another. Didn't think i'd ever type words expressing awe for a cable .

These cables are not exactly cheap but recently I too have bought two of them and they are great.
So nice in the colder months that they are still as flexible as ever and they just ooze quality.

Steve

As Peter says depends on your budget.

Also I guess what you want to image. I am sort of guessing DSO's.
The thing with modified DSLR's is that you get a lot for your money, bigger chip.

But , for me at least ,changing to a dedicated mono camera changed my imaging no end, but it wasn't without considerable cost.

I guess you have 3 main choices:

1. Modified DSLR - cost £200 to £600 depending on camera type and age of camera. You may well get one under £200 if bought 2nd hand already modified.
2. Dedicated OSC - cost £600 to £2000 (obviously can be much more but assume you are not going all out)
3. Dedicated Mono  + FW and Filters - cost £1000 to £3000 (same caveat as above)

The costs are very rounded figures, especially for mono and will vary depending on 2nd hand or new and what camera you get. Also it really depends on the makes of filters you get, and generally with filters you get what you pay so the mono route cost can vary hugely.
But, also the dedicated mono route is the most versatile and in areas of bad LP or when moon is near full then NB filters can be a huge advantage.

There are NB filter options for colour cameras too but not so versatile as the mono option.

So if like most of us you are limited by your budget I would say what that budget is and then see what that will buy you for each option.

Steve

Bloated - yes to an extent, but I think they are pretty round.

I am probably not knowledgeable enough to say what , if anything, is wrong with this image.
But I do not think there is too much wrong with it.

Stars are pretty round, maybe in corners a little elongated but not by much.
I do not think they are too far out of focus but you would have to look through all the frames rather than the final stacked image as if you are auto focusing at regular intervals then maybe some are pinpoint focus and others not so.
Not sure what software you are using, or were using in 2017 but as I have found out lately auto focus can be tricky to get just right.
Also again would need to see some raw images as bloating will probably be from the processing and nothing to do with the acquisition.

What are the individual frame exposure details ?

As I say I probably am not advanced enough to help anyway but I think more details of how the images were acquired and the software used to process would help.

But, and it is a big but, from a novice perspective, I would say that maybe the galaxies need more data (more frames or longer exposures, or both) so that you do not have to be so aggressive in the processing as unless you do something like removing the stars with Starnet (or using star masks)  partway through the processing so you can further stretch the galaxies without bloating the stars and creating the magenta halos, and then re-introduce the stars this effect on the stars will happen.

Also depending on the processing software you are using there are ways to remove magenta halos (or at least reduce them) .

Steve

Very nice build.

That must be Thunderbird 8 then is it ?

Steve

1 minute ago, Dave61 said:

Funny thing is, when ever I buy a camera or new lens the weather goes to pot.

And whats funny about that ?

All perfectly normal, FLO even put a "May contain clouds" warning label on the box 🙂 
 

Steve

1 minute ago, ollypenrice said:

I stopped learning anything about image acquisition years ago. Processing, though, is a never ending... er... process!

lly

Whilsts I am not in that position just yet I do now realise how true that statement is 🤣

Steve

27 minutes ago, Astro Noodles said:

Northern England is not great for cloudless nights.

Well that's an understatement if I ever heard one, 🙂 
I think 2nd half of last year and beginning of this was worse than normal.

But just have to make best of what we have, that's why I wish I had an obsy to make the most of any odd hour of clear sky, whereas now if I think it wont be clear most of night I just don't get the gear out as it is quite a heavy setup. If I had the obsy then just open the roof and go for it.

Steve

3rd and final attempt.
Only thing I was not keen on in 1st attempt was the bloated stars and the halos on the stars, on 2nd attempt I did not like the colours in the Nebula. Also I felt the amount of stars tended to overpower the target in both images.
So had a final try removing stars part way through processing to keep the stars small and before the halos developed. 

And before the stars were put back

Dynamic crop of LRGB
RGB Combo
DBE on Lum
ColorCalibration
HistogramTransformation RGB
HistogramTransformation  Lum
HDRMultiscaleTransform
LRGB Combo
SCNR
Starnet to remove stars
HistogramTransformation LRGB
CurvesTransformation to deepen the blue colour
Final Histogram transformation
Pixelmath to add stars back in

Steve

17 minutes ago, blameTECHIE said:

And an Amazon purchase of an external wifi dongle so I can get my RPI/Astroberry working from the very top of the garden with a bit more signal strength/stability, thanks to @Stuart1971 & @teoria_del_big_bang for their comments on an astroberry network problem post (I've gone full "belt & braces")

I really hope it works for you, it did wonders for me 🙂 

Steve

1 minute ago, rsarwar said:

The P2 filter will definately reduce your NB photons due to transmission loses. so it depends if you want to count every possible photon or happy with a 5-8 % loss.

I must admit I always intended to test it with and without and maybe it is not doing me any favours.
Unfortunately not a lot of NB targets about now and astro darkness fading but definitely need to try without when I can.

Steve

1 hour ago, rsarwar said:

Is it worth while putting a IDAS P2 filter in front of the LRGB filters? not sure how to address the light pollution for LRGB subs

1 hour ago, SyedT said:

wouldn't add any more glass into your imaging train; IMO the less material between the sensor and the scope the better for image quality. Most streetlights nowadays are LED which are broadband (as opposed to the old sodium vapour lights which could be filtered out), and so can't be blocked out as easily without having a knock on effect on your image quality. One way to tackle LP is using shorter subs, so-called "lucky imaging". It has the added benefit of requiring not-so-good guiding, and is exactly where CMOS cameras excel.

These two comments have got me thinking now.

Most of my recent imaging has been NB and for a long while now I have always had a 2" IDAS P2 permanantly in the image train (inside the flattener).
My thinking that it will not affect the NB imaging in anyway as the utra NB filters wavelength is outside that the IDAS filter removes anyway and that it would only help the small amount of LRGB imaging I do (only in current galaxy season when moon is not near full).

But maybe it is not helping my LRGB ?
I still assume it has little effect if any on the NB stuff.
I always intended to do some testing with it in and with it out but never got on with that.

Steve
 

8 minutes ago, iapa said:

If you want sleep - change your hobby

Ha Ha Ha, best advice so far - but who wants sleep 🙂 

Steve

So wheres all the awful images you didn't want to post ?

Only joking. 🙂 
There are some good images there, okay the one of the pinwheel has trailing stars and we have all been there and I certainly still get them sometimes for whatever reason.

So do not be so hard on yourself, for early images I am well impressed, yes you have a way to go to improve on them but that's where we all started and most of us still improving. I now think I produce some reasonably good images, and for sure miles way better than I thought I would ever do 3 years or so ago when just starting out.
But still when I see some of the images produced by the better imagers on SGL ,or other websites, by our members I realise I am a long way off their standard and I put some of it down to their equipment, but in many instances it is comparable, or in some ways inferior equipment to mine (or considered inferior)  and that is down to their experience and practice and most of all dedication.

Will I ever be that good ?
Who knows, I guess maybe but maybe not, but I am really not too bothered.
I stick my tripod and rig outside my house on my patio, with security lights coming on all around the other houses and car headlights passing but still produce reasonable images, in focus, no star trails that years ago would be impossible and I feel proud of what I have achieved.
And most of all, the important thing is I enjoy it 🙂   (Most of the time!)

Steve

Even the M101 is recognizable, some star trails which we all suffer from time to time and often when starting out.

I would agree, certainly no shame in that image of Orion Nebula,at all and I would say better than my first few attempts.
Stars are a bit bloated with halos but I think probably due to the processing and maybe having to over-stretch the image to see the DSO, but they look pretty round and I think pretty much in focus. Colours look good, all in all I think a good image.

And as Scotty points out it would not have been best time of year to capture this as it would have been low down and probably disappeared early on in the night.

So I certainly would be proud of that.

Steve

23 minutes ago, Astro Noodles said:

Thanks Scotty. That's far better than anything that I have managed so far. I am trying to concentrate on focus, polar alignment and finding subjects at the moment. Also processing, exposure length and iso settings are proving difficult. 

May I enquire what sort of kit you are using? 

Same sort of things I went trough for sure, even polar alignment had me baffled for a month or two and could just not understand how to do it perfectly, I was getting somewhere near but never great alignment but after asking on SGL it eventually fell into place, and then became pretty much a 5 to 10 minute thing at the start of a session.

Focus again takes a bit of getting just right and in very basic terms approximate focus can be done just by trying to get stars as small as possible, focus in a direction that reduces the blur and as they become smaller and smaller eventually if you keep going the same direction with focus they start to get bigger again.
Often for early images that is sufficient but for better focus you are in no doubt about you need a Bahtinov Focusing Mask.

Exposure length and ISO should be relatively easy and advice will be given on SGL to your best settings if you ask.
Really the exposure length depends on how good your equipment follows the target. Without guiding I think you may have to limit to 30 seconds, but then you still need the mount to track accurately, so good polar alignment and a reasonable mount is still required.
Also unfortunately for DSO's in UK it is not the best time of year and for starting off it is best to choose something relatively bright, most Nebulas are very low down at least until after midnight and on top of that nights are getting short so it is probably the most difficult time of year to start out.
Maybe pick some star clusters to image as they are generally reasonably bright, but pretty small, but good to practice as the idea is to get images without stars trailing and it all helps.

Maybe start off listing the equipment you are using and any of your recent images, no matter how naff you think they are, would be a good start for people to give you some help.

Steve

If you take a minute and think about what you are trying to do it is a wonder any one without £10,000's of money to throw at it get any sort of image.

You are trying to train your scope an an ever so tiny piece of sky and collect photons on a cameras sensor that have been travelling through space for Thousands of years and there are so few of these photons that you would struggle to see all but the brightest of them at all by eye even through a telescope.

So in actual fact any sort of image is an achievement, especially without all the more refined equipment.

I too when I started was a bit worried about putting my early images on SGL as so many were unbelievably good but don't.
People on here accept there is both a learning curve and an equipment gathering curve to get to a decent level of imaging.
But still putting those first images up can help you tremendously as people will offer really good advice on how to improve those images with what you have, maybe suggest what equipment to invest in next if some of it is not ideal.

Believe me nobody will say anything discouraging and any criticism will only be done to help you advance your own skills.

Often people post images of a nebula that just looks like a load of stars with no recognizable image of a DSO and others can take that and do some further processing that brings out a feint image of what they were trying to image and explain what they have done, and that really encourages you as you obviously then had done something right but were just unable to process the images correctly.

Regarding how long it takes, well unfortunately that's fairly difficult to answer.
A lot of it is good equipment that helps, but a lot is practice and knowledge so getting out there on any clear(ish) night and giving it a go, but then post the images to get advice and help you with the processing side - and read up on it, lots in books or on line.

I have been into AP now around 3 years and I did have some recognisable images after around 3  months (only with help from SGL!) but not what I would call good images, now with some more equipment the images are getting better but I think it is something that improves with time and great images can take many years.
But also I see many fantastic images with fairly basic DSLR cameras and basic tracking mounts so not all people spend £1000's.

Steve

A 2nd attempt all in PI. Similar process to before but I used Starnet to remove stars for some of the processing to stop them getting bloated.

Dynamic crop of LRGB
RGB Combo
DBE on Lum
ColorCalibration
HistogramTransformation RGB
HistogramTransformation  Lum
Starnet on both RGB and Lum to remove stars and keep stars seperated for now
HDRMultiscaleTransform
LRGB Combo
SCNR
HistogramTransformation LRGB
CurvesTransformation
Pixelmath to combine LRGB and Stars

Steve

Great images 🙂 

Steve

1 minute ago, JamesF said:

You mean you haven't been wearing your pants outside your trousers all day?!

James

Working from home, who wears pants anymore 🙂 

Steve

Yes very well deserved, I bet you are  over the moon 🙂 

Steve