LaurenceT

3 minutes ago, paulastro said:

Five minutes from an hour is a poor return.  Was it a little windy, or perhaps cloud interfering or even an obstruction?  I've noticed  that they are much better at reacting to conditions than I am. Usually when I hadn't noticed  that cloud is increasing or there is some wind.  Mine doesn't usually go below at least a 2/3 success rate.  It did once stop for about  fifteen minutes and I thought it had frozen somehow or had broken down.  Re- booting it didn't work - and then I noticed it had completely clouded over where the object was!  🤔

You could be right about the conditions but it didn't seem to affect my other setup. One thing that has baffled me is that the subs were labelled IRCUT files so I obviously failed to switch to the dual band filter, I had thought it was automatic when selecting a DSO, obviously not so no nebulosity!

I'm still having a struggle with my new Seestar, last night when I suddenly realized there were stars to be seen I had a go at the Flame Nebula.

I imaged for 1 hour but had so many rejections due to star trailing that I've only finished up with 5 minutes of subs.

Just to make an unfair comparison I also quickly set up my lightweight wide field kit and got an hour on the same target losing only 2 frames due to clouds. I'll do some processing later.

I haven't yet watched the video, maybe he mentions it but I've read that the sync button has disappeared because it's now being done automatically.

Edit: yep, it's in the video! 😳

First clear night at about 23.00 so I chanced my luck and tried some lunar. I've only had the Seestar a few days and managed to image the sun within a few hours of opening the box without problems. Last night was a different matter however, it simply couldn't find the moon even after levelling and compass calibration.

So I tried selecting some random nebula which it slewed to immediately and did a 3 star calibration. I backed out of that and tried the moon and it found it perfectly so I took a few videos during which it tracked perfectly. I still have to work out the finer details of AF when the green box is not on the moon. The sky looks clear right now so I might try some more solar.

Image is a 1 minute video processed in Pipp, AutoStakkert and Dxo Photolab 3. It had a green tinge so I converted it to mono in Nik.

Looking at the specs of the Celestron I'm sure it would be a  fantastic instrument.

4 minutes ago, Beardy30 said:

Sorry I meant price aside capabilities wise and quality wise obviously- be interested to see if it’s worth the upgrade 

I think I'd be more inclined to buy 6 Seestars for that money and establish The Large Back Garden Seestar Array.

Edit: Actually I wouldn't 😄

First image, took all of 2 minutes after unboxing, clouds and sunspots are included apparently.

It arrived this afternoon and it hasn't stopped talking to me! Took all of 2 minutes after unpacking to take this shot of the sun, clouds and sunspots included.

21 minutes ago, LDW1 said:

If it is only arriving today you may change your mind about how and how much you will use it once you do !

I hope to use the Seestar to it's fullest capacity.

4 minutes ago, StevieDvd said:

That's possible under certain scenarios:

• The images are heavily cropped, rotation artefacts are in the four corners.
• The post processing is heavy and the corners artefacts processed out
• The 2 hours are comprised of several nights imaging with short exposures 
• The final image is sharing data from several peoples sessions
• It's Facebook so must be true🙄

Yep, that makes sense, particularly the last bit🤣. Thanks.

2 hours ago, Geoff Lister said:

I too, have not had significant problems with field rotation effects on the Seestar images; but I have noticed it more with my Dwarf II. If you are going to be spending hours gathering FIT files for off-line processing, you are, perhaps, missing the point of these lovely little 'scopes. They both work at their best, capturing for a few minutes, with a "Live" display on your tablet's screen, and a download of a nice JPEG image for your records, - then a quick slew to the next interesting target, and start "Viewing" again.

I found a very good web site that explains field rotation with an Az/Alt mount.

https://calgary.rasc.ca/field_rotation.htm

About 2-thirds through the document, there is a very nice 3D graph showing field rotation with respect to the target's azimuth and elevation. As far as I could conclude, for minimum rotation select targets near the horizon, and towards the east or west. Anything close to the zenith is bad for field rotation, (and anyway would be challenging for any Az/Alt mount).

Geoff

What initially drew me to the Seestar was as an EAA replacement for my existing mini setup. I had been using the Evoguide 50ED EAA setup as described by Cuiv on YT. It was very quick and simple. All you needed was a mount like the Az GTi, an Evoguide 50ED and a Raspberry Pi with Stellarmate, I already had all these. All you had to do was level the scope and point north and away you went doing easy EAA. That was the theory anyway. To paraphrase Longfellow, when it was good it was very good, when it was bad it was horrid. So horrid in fact that after using it for the best part of last year I tore down the setup and gave up EAA, at least temporarily.

The Seestar will do all of that for me with the additional bonus of taking reference images as you point out or if so inclined go the whole hog and do serious post processing. I've been referring to Telescopius in the past couple of days and realise the shortcomings of  the Seestar scope FOV (it's essentially an Evoguide 50ED anyway) and realise that for different targets I will still rely on my other imaging scopes which is fine.

My Seestar is arriving today 🙂.

4 minutes ago, DaveL59 said:

A search back on the thread would find posts about mounting the S50 on a wedge arrangement and using the advanced features to handle star alignment. This would reduce/eliminate field rotation tho at the expense of some loss to how low you can target IIRC. Not tried it myself yet but others here have.

The use of an equatorial wedge was denied by the Seestar users on Facebook that were claiming zero field rotation in integration times of 2 hours plus.

I've been getting this a bit wrong, surprise surprise! It wasn't a single exposure at all but 2hrs 35mins of 369 stacked images but even so I would expect considerable field rotation seeing that reviewers have suggested less than 1 hour on any single subject to avoid rotation. Have I got the concept of Seestar field rotation wrong?

8 minutes ago, happy-kat said:

East and West up to 50 degrees or so northern hemisphere would show little to none the lower the altitude and plus being portrait helps not exaggerate it

Many thanks for that Kat

7 minutes ago, happy-kat said:

The orientation of the S50 is portrait and exposure length short individual frames wouldn't show field rotation that obvious though target direction influenced. A stack would through I expect from first to last frame. If you had 300 frames and stacked just one every 50 frames you might see the rotation by the way the frame edges where outlined on the stack

Thanks, so would a single unstacked exposure of 2.5 hours show field rotation?

1 minute ago, Elp said:

If you register and stack the individual images on a computer afterwards you definitely shouldn't see field rotation as it's no different from "normal AP", I would have thought the in built stacking works the same but a user can confirm this.

I would have thought that the fact it is an alt az mount is the biggest factor in it's field rotation which makes it different from 'normal AP' which is done with an EQ mount.

The Facebook comments seemed to suggest that ZWO have introduced something into the firmware which corrects for this.

I've been thinking about getting one of these for a little while and I've been watching many YT videos. I've also joined a couple of Facebook user groups to read more. I've been aware of the problem of field rotation and had read in many reviews that because of this integration time of over an hour was not recommended.

Yesterday I saw a Facebook post claiming 2.5 hours of integration time without field rotation. When I commented about field rotation I received these replies:

"Seestar uses a Plate Solution to align and register the stars. Once aligned it adds the result to the stack. At least that is my understanding and it seems to work well over the 2 or 3 hour time span"

 "The SeeStar will automatically align the rotation of each image as it is stacked. The outcome will have a fully register object but the outside edges of the image will show skewing. It is more apparent when using the individual images and stacking them on a computer."

Is this now the experience of other users?

Anyway, I ordered one yesterday (not based on this information), hopefully will arrive tomorrow. 

Thanks for the replies everyone and apologies for not responding sooner but I've been in Devon for a friends funeral.

I'll spend tomorrow reading and digesting all that's been written here.

I discovered the disadvantage of a square sensor, no matter how I rotated the camera I couldn't get it to fit and then I had to crop it a small amount. I really should have used my Askar FMA 180 and got the Soul nebula as well.

It was a first for me as I took some flats as well, don't know of they made any difference. Also I failed yet again in setting up guiding, seems to be a blank spot for me so all subs unguided. Also I never quite know how set the red colour, sometimes too light other times too intense!

WO ZS61ii, SA GTi mount, Asiair Plus, L-Enhance filter, 150x60 second subs. Astropixelprocessor, Photoshop, Gimp.

Well done Lee, it's a lovely image. By coincidence tonight was the first time since coming to this hobby that I took the plunge and took my first flat frames!😀

Brilliant use of a vintage lens! What lens were you using? I've got a couple of older Canon FD lenses, my favourite being the 135mm F2.8. I know I could use this for astrophotography but because I already have an Askar FMA180 it doesn't seem worth it.

However, having seen what you are doing has made me think again. All it needs is a few adapters (famous last words!).

Excellent image,  I like the detail in the core not being blown out.

3 minutes ago, mikeDnight said:

I could, but my granny told me "Neither a lender nor a borrower be"! There you go, I've saved you from being enslaved to debt! 😊

Kind of you but I've got a dead cert bet on Villa on Saturday. honest Guv.

All this talk about community and helping each other has  given me the courage to ask one question.

Can someone lend me a fiver until Saturday....................................?

🤣

Thanks for the replies but I've put the tube on my mount and although the total weight of the tube, camera, Asiair and guidescope/camera is within the 5KG limit I cannot balance it in the RA axis with the supplied counterweights. Rather than put strain on the mount I think I'll abandon the project and stick with my WO ZS61 as largest imaging scope.

Once again thanks for the replies.