Owmuchonomy

1 hour ago, Ouroboros said:

How significant is field rotation over a minute or so?

Would using a CMOS camera with their short exposures of 60s or so allow you to get away with it?

Also for planetary and lunar imaging, do the various processing apps compensate for field rotation? 

Autostakkert can compensate for field rotation. All my solar and lunar images are taken in AltAz mode. Obviously, one has to crop out for missing corners but it’s not much.

Hi.  I have the same mount and it is usually very reliable.  I will mention the most common cause in my view which is poor power supply.  What are you using for your power?  Another possibility that I admit to encountering myself is to mount the OTA the wrong way round.  This can produce the effect you describe. On my set up and software version it is critical that the OTA is inserted a particular way into the mount dovetail.  My understanding is that later versions of the software circumvented this. On my version the objective needs to face away from the 'FREEDOM FIND' lettering on the mount body.

It’s some time since I battled with this problem but a radial elongation in each corner is generally considered to be a spacing issue. Is the set up you have specified to fill your chip with a flat field? If not it could also be field curvature.

As above plus with some phones you will have to ‘force’ it to focus, i.e., with an iPhone touch the screen where the bright image is to focus and also bring up the exposure control.

Neither mount will be sturdy until one upgrades the tripod.  I run my AZ-Gti on an old EQ6 tripod.  That's sturdy!  I use all sorts of scopes on it, ED80, Lunt solar scope, SW 150 Mak, WO Megrez 90 etc.  No AA battery mount in my experience will run or track reliably until the power supply is upgraded. I use my Dewalt cordless drill battery (with its USB charging hood) stepped up from 5V to 12V using an adapter cable.  The cable can take 800mA which is more than enough for the mount.  One battery will last two nights between charging. Alignment? It's a doddle using the Synscan App on an iPhone. You can choose various options for that like Brightest Object, North level etc.  I often use the setup for Solar imaging and it tracks fine all day.

My 7.5 to 21mm zoom earns its living when solar viewing.  It's an excellent device for defeating seeing issues during daytime viewing.  Small adjustments can help get round the ever changing solar view affected by the elements.  Dark sky observing for me requires a handful of fixed focal length EPs, I don't get an advantage with my Lunt zoom.  The other slight problem with the zoom EPs I have owned (particularly Baader) is the poor eye relief.  The best investment I made was in the TV Delite options; marvellous EPs if you have the budget.

Work backwards from the planetary cam you wish to use to ensure you match the scope to that. You may be better with one of the big SCT options.

Unfortunately the lead time on these is long but in your shoes (I use similar when in the caravan) I would go for this option. Portable and Easily used remotely via a smartphone and you will get pretty decent views. Attach a smartphone with a neat EP holder and you can get great Moon shots. For the price it’s excellent. You will have to pay a lot more to go APO so a little CA will be apparent. 
https://www.firstlightoptics.com/startravel/sky-watcher-startravel-102-az-gte.html

4 hours ago, SStanford said:

Thanks @Owmuchonomy, 

Have you found 2-Star alignment is sufficient for this process? I thought you needed at least 3 for adequate alignment error...

If 2-star works then that's perfect.  I using the Crosshairs shown on liveview via APT and zooming in to increase accuracy.  Can you see any issues using this method rather than an EP?

For imaging one should use a 2 star alignment using 2 stars on the same side of the meridian as your imaging target. A 3 star alignment adjusts for cone error in your set up so it’s more of a compromise. So yes, a 2 star alignment is more appropriate. I use mk 1 eyeball so can’t comment on using APT software.

If you have a Synscan handset then it is all in there. Do a 2 star alignment then use the polar alignment routine option built into the Synscan menu. No need for Polaris or a polarscope but use a relatively high power EP. It will probably take 2 or 3 iterations to get it close enough for imaging.

Great advice above on the book. Don’t be hasty to move on the ED150. If you want to image galaxies it will be spectacular.

Great results are obtainable with an ED80.  It has a long pedigree at an affordable price particularly with those starting out in deep sky astrophotography and is perfectly suited to your HEQ5. Have you got some examples of the images you have captured so far that you could share?

Perhaps you could tell us a bit more about the types of targets you wish to capture with your future set up.  In that way we can advise you accordingly.  Many thanks.

Newtonians on EQ mounts can present uncomfortable eyepiece positions for the observer, necessitating tube rotation within the rings when moving around the night sky.  If you can live with that then an 8" Newtonian gives pretty good views (ignore the hype in the Ad).  I have no experience of the GoTo software on that mount so cannot comment on accuracy, software support etc. 

4 minutes ago, AlanP_ said:

Oh, well that may change my plan on using that so. I seen this one in one of the threads @teoria_del_big_bang linked. Its a bit out of my budget, but would it be a good option for me?

Quite possibly.  I know someone in the Dales who runs his Meade SCT and mount with one of those and swears by it.

I have personal experience of 'Powertanks' whether SW or otherwise and I was very disappointed.  They both lasted a few months and gave me 30 minutes maximum when plugged into my HEQ5 Pro.  I would concur with that said above and go for a leisure battery option.

2 hours ago, varius21 said:

Thank you everyone for your tips.  ❤️
With everything everyone is saying in here I am leaning towards Asi224mc

am I right in doing so? 

If you want to do colour planetary imaging then yes.  However, two more things to consider:

1) With the exception of Mars (which is getting much smaller by the day) the other juicy targets are not very well placed at all.  So the opportunities to image are somewhat limited for a few years.  Jupiter improves gradually over the next 3 years.

2) Your Dob is about f/6 I believe.  If so, you will need at least a 2.5x Powermate or decent Barlow to get the required image scale.  A rough approximation is to multiply the pixel size of the camera by 4 or 5 to see what f/ you will require.

Regarding DSLRs the advice above is very good.  The correct parameters are hard to find; i.e., fast video frame rate and true video crop mode (1:1).  A 550D does it or a 60D too.  In your shoes I would get an ASI 290 mono camera and play with imaging the Moon or Venus to get used to planetary imaging.  If you can get one pre-loved, all the better.  They retain their value too.  Your biggest problem will be finding and staying on the target.

My first ever astrophotography effort was using a Canon 600D, an EF300mm f/4 lens and an HEQ5 pro mount. I personally wouldn't go heavier than an HEQ5 pro until you have a permanent set up.  I built an obsy and installed an AZ EQ6 GT.

Excellent topic and presentation.  I really must dig out my SA100!

Looking at your subs, the whole frame is suffering with oval stars to a point so I guess the tracking/guiding is not optimum.  Regarding the corners is it worse on the chip that is the largest?

A lot of hard work has gone into creating one of the largest dark sky areas in Europe (3,600 sq km).  It's a great result and well done to all who made it happen.  I'll be up at Sutton Bank later to face the press.

https://www.darksky.org/uk-dark-sky-reserve/?fbclid=IwAR291jgzyvTEY71ctxV5lDqvmkX9RjbNikRK-rbHSbb181LQ15cCpgNJrjo

I was up at the Obsy waiting for materials for the Planetarium dome on Wednesday and the sky miraculously cleared about 1pm.  So I set up the Lunt and took a few full disk clips with the ASI174MM.  The seeing was shocking; I don't think I have tried imaging the Sun so low in altitude (I can't do that from home).  Anyway, here are the results.

Hi Richard and welcome. Polar alignment is not necessary with that scope or type of mount.

Fantastic images!

Post a photo please of how you have set it up for eyepiece viewing and we can supply a possible remedy.  Daft question, but are you using a mirror diagonal?