M81

[alan4908]

I'm currently evaluating CCD Navigator and ACP Expert and so I decided to test the combination on M81. Given that I also need to calibrate my new autofocusing software (FocusMax) and investigate why ACP was giving incorrect Pierside reporting, I decided to accept non ideal imaging conditions (eg moon up). 

Given these limitations, I was quite happy with the result. LIGHTS: 14 x 600s; DARKS: 30; BIAS: 100; FLATS:40 all at -20C.

(For anyone interested, I resolved the ACP incorrect Pierside reporting to a change in EQMOD. To make ACP compatible with EQMOD , in the current EQMOD release (v1.28k) you need to select v1.24g in the driver setup. I suspect that this subtlety will impact other ASCOM based third party applications).

Alan

[laudropb]

Nice image. Thanks for posting.

[alan potts]

A nice image, I saw that small galaxy nearby with my 18 inch last time I looked that way, it is behind the hill now and too low down from here.

[WaveSoarer]

That's excellent.

[michael.h.f.wilkinson]

Very nice result. Not just M81 but M82 and NGC 3077 as well. I have a soft spot for that latter one, as it was my first non-Messier NGC, logged and sketched on October 22, 1979

[pyrasanth]

Nice detail but it looks a bit to red for my liking but opinions may vary. I've not done much colour work but I get a feeling that it is not easy to get a good colour balance.

[alan4908]

Thanks for all your comments. 

Michael - yes, I agree it was good to see NGC3077 in the image as well (along with M82). It is not often you get three for the price of one !

Pyrasanth - I agree with your generic comment on colour balance on astro images, I also find it difficult to achieve.  I'm hoping that the more practice I get, the easier this will become.  

Alan

[Stephen Green]

  Very nice image

Stephen

[chrisshillito]

(For anyone interested, I resolved the ACP incorrect Pierside reporting to a change in EQMOD. To make ACP compatible with EQMOD , in the current EQMOD release (v1.28k) you need to select v1.24g in the driver setup. I suspect that this subtlety will impact other ASCOM based third party applications).

Hi Alan,

For the northern hemisphere the V1.28k "pointing" method for peirside reporting passes both ASCOM official conform test and a dedicated PierSideTest application written by ASCOM developer Chris Rowland. Releases prior to V1.28k did have an issue with that mode but V1.28K was supposed to fix that - and the feedback I've had so far (but from SGP users not ACP users) was that it had. Can you please confirm that there is still an issue with ACP when using the "pointing" mode.

Note that V1.28k does still have an issue with the southern hemisphere ("pointing" returns east and west swapped) but this has been fixed in the EQMOD V1.28m release issued recently to the EQMOD Yahoo group.

Thanks,

Chris.

[alan4908]

Hi Chris

To explain a little more fully: I encountered the Pierside reporting issue whilst using version of EQMOD (v1.27l) with my evaluation copy of ACP. After driving me slightly bonkers for several days, I concluded it was likely that the ACP issue was due to change in EQMOD Pierside reporting, I came to this conclusion since another ACP user had reported everything was OK with  EQMOD v1.24g.  I also discovered that the later versions of EQMOD had implemented an option that allowed users to specifically select the Pierside reporting option of v1.24g.  So, I decided to test my theory by downloading the latest version of EQMOD (v1.28k) and setting the driver option for Pierside reporting to v1.24g.  Since it worked I was happy.  I also concluded that there must be ongoing issues with Pierside reporting in EQMOD, since if everything was resolved then there would not be a need for a driver option to select v1.24g.

Following your suggestion, I've briefly tested  v1.28k with the Pierside driver set at pointing and I seem to get the same results as setting Pierside reporting at v1.24g, eg it appears to work with ACP.  

What I still slightly confused about is this..... if you put the Southern hemisphere issue to one side, if v1.28k with Pierside reporting set to pointing is identical to v1.28k Pierside reporting set to v1.24g, then everything seems to have come full circle - which doesn't seem to make sense.

Alan

PS -  I really like EQMOD and I think you've done a great job in developing it.

[chrisshillito]

What I still slightly confused about is this..... if you put the Southern hemisphere issue to one side, if v1.28k with Pierside reporting set to pointing is identical to v1.28k Pierside reporting set to v1.24g, then everything seems to have come full circle - which doesn't seem to make sense.

Hi Alan,

Yes there is a hint of going round in circles, but actually its more of a helix!

Way back when EQMOD was written the ASCOM SideOfPier property was rather loosely defined. EQMOD came up with its own interpretation of what SideOfPier meant and what you got is essentially the V1.24g type implementation.

Some time later ASCOM decided to firm up the definition of SideOfPier and changed the SideOfPier documentation to specifically refer to "pointing state". This included the  following comment:

"For historical reasons, this property's name does not reflect its true meaning. The name will not be changed (so as to preserve compatibility), but the meaning has since become clear."

This, in combination with another comment in the DestinationSideOfPier documentation that strongly implied there was a change introduced with ASCOM platform 6 , had me convinced that something had fundamentally changed not only in documentation but in implementation. The original SideOfPier code had not been written by me and did not appear to follow precisely the same method that ASCOM had now provided in their development notes. These notes also made a clear distinction between pointing and physical SideOfPier and assuming that physical must be the method that did "reflect the true meaning" of SideOfPier I thought I that to cover all bases I'd code up both.

Unfortunately I messed up the "pointing" method by reporting a swapped state (i.e. east is west, west is east)  and northern hemisphere folks found that SideOfPier was no longer working and requested that the "old" method was reinstated. Not wanting to take a potentially backwards step, and because not everyone was having problems,  I just added V1.24g as an option. I subsequently fixed the "pointing" swap (V1.28k) which made things work for the Northern Hemisphere but broke it for the southern (despite the fact that ASCOM's conform utility assured me all was well).  V1.28m aims to fix things so the "pointing" works correctly for both northern and southern hemisphere

So for the moment you get a choice of four PierSide methods:

None - no PierSide pointing. This is an ASCOM compliant method and forces client apps to work it out for themselves - if they can.

Pointing - ASCOM compliant method  - this is the default aster a clean install.

Physical - An ascom documented, but non compliant, method.

V1.24g - Works for many, most of the time, and has been a useful stopgap workaround whilst issues with the pointing method have been ongoing.

Perhaps in time EQMOD can go back to a single default method that just works, but for the moment the various options remain to provide backwards compatibility for folks who may have written software/scripts based around them.

Chris.

[alan4908]

Chris

Thanks for the clarification, I was curious about the background to all these EQMOD options. As you imply, the desire to maintain backwards compatibility with existing third party applications tends to imply that these options will be around for quite a time.

Alan