Need help with my step by step instructions please

[ianpwilliams]

Regarding your power cables Dave, did you remove the connectors yourself and solder on the XLRs? Because I don't think I would be skilled enough to do that. But I do wonder if I can buy a better cable with good solid XLR connectors or similar?

The ones I got from Maplin have screw terminals, just need to make sure you get live and neutral the right way round.

I can see M31  through the view finder enough to centre it

Davr

e

You must have darker skies than me then!

I think I'll just tape them together for now.

And I've updated my setup guide as well, ready for next time.

HEQ5 Step By Step Imaging Setup Guide.doc

[Yearofthegoat]

Thanks for posting the guide Ian.

[Davey-T]

You must have darker skies than me then!

South East London so not much different to Edinburgh, have you tried through the view finder ? I can't see it in live view.

Dace

[ianpwilliams]

I didn't try through the finderscope, I'll have a look next time (although it may be a different target depending on circumstances).

[ianpwilliams]

I've actually taken three shots of the moon recently, finishing with full moon. So I made a montage of them!

https://flic.kr/p/pnJjMP

[ianpwilliams]

Thanks for posting the guide Ian.

No problem, hope it helps. And it may not be entirely correct, and I'll be happy for people to point out any errors.

[ianpwilliams]

Thinking about it, it would make more sense (in my opinion) to determine the longest available sub length first, and then determine the best ISO setting for that sub length, so I've updated my list a bit to reflect that.

HEQ5 Step By Step Imaging Setup Guide.doc

[Willi1972]

Great thread! On the subject of 12V power, it would be worth looking at batteries on eBay. I picked up a 27Ah for €11. Also for an eq5.

[carastro]

Just a few comments on your "work flow" list:

You say to avoid imaging an overhead target because of dew.  Not sure what scope you are using, but if you have a refractor dew is easily taken care of by the use of dew heaters.  Yes more expense but worth their weight in gold, and of course another item to run off your power supply but they take very little power!!!  for which will also need a power supply splitter.

I am not sure about all this "deciding on which iso to use"  Using anything higher than 800iso normally produces noisier images.  

Bias frames.  These can be taken at any temperature and you can take one batch and re-use them - no need to take them every time.

Dark frames.  These are temperature dependent and with a DSLR should be done during the same session, but I wouldn't waste too much imaging time taking them, they can be done during passing clouds, or a few whilst setting up, or waiting for the clouds to clear.  

Flat frames:  You haven't mentioned these, and these are essential for good results.  They can be difficult to get your head around to start with and maybe you can wait a few sessions to get to grips with your current challenges first.  But they remove dust particles, and vignetting (dark corners and bright centre) of your image by being applied in DSS.  This is an image of your light train only and they need to be done by just imaging the light path.  In some respects this is easy with a DSLR as you can just set you camera to AV and 100iso and point at a not too bright even light source.  I used to do this the following day by putting a sheet of typing paper across the aperture of the scope, and pointing at a dull part of the sky.  Without a permanent set up you have 2 choices.  Provide a light source by using a light box or dim white computer screen (an Ipad might do the job), and it can be dulled down with a number of sheets typing paper.  Or leave the camera attached the the telescope and do them the following day. You do not need to put the scope back on the mount.  I did this once when I realised I had forgotten to take them at camp after I had half de-rigged and so I brought the scope and camera home intact and took them through the bedroom window still using the typing paper over the aperture.  N.B. you must not move the camera or focus before taking flats or the dust won't line up.

As I say, just get used to what you're doing at the moment, but in the meantime have a think about this and how you can best achieve it.  

Sorry to throw yet another spanner (or two) into the works.   

Carole 

[ianpwilliams]

No that's fine, I need to know these things!

So for Bias frames, we are talking telescope cap on, shortest exposure possible, and lots of shots for various ISO levels so that I have a library of them?

And for Flats, I was thinking that maybe I could point my scope at a white dim computer screen (although how would I know how dim or bright to have it?). Would I still then need the piece of paper over the front of the telescope? And would I be taking all shots at 100ISO? And could I take lots of shots for various exposure lengths (30 seconds, 60 seconds, 90 seconds etc), so that I had a library of them too?

And assuming I get some Bias and Flats taken, could I use the ones that match the ISO and sub length (in this case 3200ISO and 30 seconds) of my M31 session the other night, and re-stack everything?

Also, what is AV mode on the camera? I've only ever used fully automatic for daytime shots, or Manual mode so I can set everything. Is AV something in between?

[carastro]

So for Bias frames, we are talking telescope cap on, shortest exposure possible, and lots of shots for various ISO levels so that I have a library of them?

Correct.  I only use one iso so only have one set.

 Would I still then need the piece of paper over the front of the telescope? And would I be taking all shots at 100ISO? 

It's best to have the paper over the scope to diffuse the light.  provided the light is not too bright if you're on AV the DSLR normally adjusts the length of sub to get the correct length, but for info the histogram should be about 1/3 full well, no more than 1/2 full well.  It's better to have the light too dim than too bright, the camera can always take a longer sub if needs be.  I.e. with AV you don't set the length of exposure, just press "shoot".  

And could I take lots of shots for various exposure lengths (30 seconds, 60 seconds, 90 seconds etc), so that I had a library of them too?

No unfortunately that's something you can't do.  You can only re-use flats if you haven't moved the camera or focus.  Also again you don;t set a length for flats, let the AV setting decide.

Also, what is AV mode on the camera?

Hmm, what sort of DSLR do you have Ian, on the Canon camera it is on the settings dial at the top, along with manual auto etc etc.

Carole 

[ianpwilliams]

It's an 1100D. I'm sure it will have AV mode, I've just never used it.

As for flats, it sounds like I'd be best off taking those after the session when back in the house, maybe pointed at the computer screen via a piece of paper, and adjusting the monitor brightness where necessary. I'd just have to make sure that the camera and focuser were untouched, which will be tricky when carrying them up the stairs!

[happy-kat]

Flats idea http://stargazerslounge.com/topic/227341-flower-pot-flats-the-test/?fromsearch=1

[carastro]

This is my flats arrangement:

I bought an EL panel and put it inside a shallow box.  I did actually also put a sheet of opaque perspex over it to keep it rigid.  

I cut a hole the size of my aperture in the lid

This is it mounted on the scope.  

I can add sheets of paper to dim the light inside the box.

It's cardboard but I keep it in a plastic bag and indoors so the damp doesn;t affect it.

I actually use this now for CCD camera imaging, previously with my permanent set up I used to use a DSLR and sky flats.  

[Mick J]

http://stargazerslounge.com/topic/150217-does-my-master-flat-look-ok/

It's possible to use a blank white screen from a computer for flats.

Don't get to involved in changing the power cable just now, tie/tape the cigar things together, sometime you will start to add other items to run off the battery, or even change the battery,  - camera can be run from an external supply, heat is somewhere else, dew heaters, guiding - there are some wonderful homemade power tanks in the diy area.   Coming along well, well done.

[stepping beyond]

I can tell you for a certainty that polar aligning just the mount is the way to go, sure you have to readjust your levelling of the mount and balance the OTA but it's so much easier than to struggle with your OTA mounted. I've got a meade lxd55/ 80mm refractor and it was a real pain until I got it down , now I can view or image within 30 min. Take your time and the more you do it , the easier it gets.

[ianpwilliams]

Flats idea http://stargazerslounge.com/topic/227341-flower-pot-flats-the-test/?fromsearch=1

That seems to be a very good demonstration of how flats would have benefitted my M31 picture, as I have that same issue with all that extra light off to the side.

[ianpwilliams]

I think I'll try the PC screen Flats method after my next session. Your method seems like a lot of time and effort Carole!

When it comes to polar alignment in my case I don't find it too bad polar aligning with the scope on. The issue with the left Az bolt being stiff isn't because of the extra weight, I think it's just a stiff bolt. But with the tripod/weight bar/dovetail marks I have, Polaris is usually reliably in the same place when I set up, and I'm also balanced, so it's all good. I'm also hopefully going to be getting the permission of my landlord to use her shed for my mount (which will be a whole new thread asking about the best way to store it, cover it etc), so if I can do that then it'll be even better, because it would only be one trip up and down the stairs, which no mount!

[ianpwilliams]

And updated version to allow for Flats.

HEQ5 Step By Step Imaging Setup Guide.doc

[carastro]

 I'm also hopefully going to be getting the permission of my landlord to use her shed for my mount (which will be a whole new thread asking about the best way to store it, cover it etc), so if I can do that then it'll be even better, because it would only be one trip up and down the stairs, which no mount!

That would be great.  Don't suppose the shed has power in there, or even if the landlord was willing to have power laid on in there even if it's at your expense, as that would make life a lot easier for you. It would also enable you to have some sort of dehumidifying capacity to keep the mount nice and dry.  

You might even be able to use a laptop then and not have to worry about the SD card getting full.

Carole 

[ianpwilliams]

Damn, clear skies forecast tomorrow night, which means doing it all over again I suppose! Ironically enough it's not the polar alignment that is the daunting bit any more, it's taking subs and checking histograms to find ISO levels, taking lengthening subs and looking for star trails, and taking flats too.

[ianpwilliams]

When it comes to flats, I take it it would cause a problem if the camera rotated to the eyepiece holder when carrying the scope back upstairs? Because sometimes it can be a pain tightening the screws enough to keep it in place, at least when carrying the scope around

[carastro]

Your method seems like a lot of time and effort Carole!

Yes it certainly is Ian, this was set up for CCD imaging where the camera had a shutter and needed longer than 3 sec exposures and I could not do them in the daytime as there was a light leak.

Oh for the days of flats with a DSLR they were so simple then.  Yes I just suggested it as an idea if you were forced to do them in the dark.

Carole 

[carastro]

 I take it it would cause a problem if the camera rotated to the eyepiece holder

You mustn't move the camera at all of the flats won't work properly.

Carole 

[Davey-T]

Damn, clear skies forecast tomorrow night, which means doing it all over again I suppose! Ironically enough it's not the polar alignment that is the daunting bit any more, it's taking subs and checking histograms to find ISO levels, taking lengthening subs and looking for star trails, and taking flats too.

Are you having fun yet 

Dave