fifeskies

Now you have a permanent home for your scope and are not setting up each night, if you intend to use more than 1 scope then it makes it easier to swap over systems if you mount the control equipment off the OTA.

The other advantage is that the reduction in weight should improve tracking.

Downside is that a little more care needs to be taken over cable management.

(There is an advantage of having everything on the OTA if you are having to cart it outside and place it on a mount and tripod each time.)

16 minutes ago, Elp said:

... what's happening with the 8 then.

It will soon be for sale (with reducer and dewshield), but want to check out the 9.25 on a few targets first.

8 minutes ago, Simon Pepper said:

Thanks and point noted thankfully I do use an OAG so hopefully shouldn’t be too difficult to transition. Was lucky enough to get the reducer as well so will keep that on as you say not enough clear nights at f10! Decent comparison image above as well it does look quite a lot larger that the 8! 

I started of with the 290mm in my OAG , but it was a struggle esp at f10 to find enough guidestars. I changed over to the 174mm and now never have any issues.

3 minutes ago, Simon Pepper said:

Makes sense. I don’t have a permanent setup yet but I am working on that. It will be my first SCT though so lots to learn I am sure after the initial excitement. Do you image with the reducer or use it at native? Thanks 

I actually image both native and with the reducer depending on target.

That said f10 imaging will take you a long time to get enough data , especially when you dont get a lot of good clear nights.

Going forward I dont see me imaging at f10 very often except on the moon. I use a 2x Powermate to image bright planets at f20.

If your new to SCT , I highly recommend using an OAG not a guidescope. The Celeston OAG has a nice large prism compared to others.

9 minutes ago, Simon Pepper said:

I have a 9.25 on the way and I am so excited. Will you use bobs knobs or do they hold colimation well? Thanks 

Its new to me so cant say how they hold collimation , however I have a set of Bob's Knobs to fit to it just in case.

My 8 never drifted so I guess they are fine , tho mine lived in a dome on a permanent mount which no doubt helps it stay good as its not ever moved about.

12 hours ago, Stu said:

As I recall, the 925 uses an f2.5 primary vs f2 for the rest of the range, that’s why it is so much longer than you expect it should be.

The f2.5 primary (and so the longer OTA) has a particular benefit for this system when loaded with an OAG and ZWO camera train.

I no longer need as much front counterbalance weight for the system.

I was using 2kg front weight on my EdgeHD 8 to get it to balance.

The Edge HD 9.25 imaging system can balance  without any front weight, as long as it sits towards the rear of the Losmandy. (with metal dewshield added.)

This means the overall mount load for the HD 9.25 is actually only around 1.5kg heavier than for the HD 8, even though the OTA itself is 3kg heavier.

It is around 14.5Kg all in (with 2nd Losmandy on top and a telrad).

(The top losmandy provides adequate front counterweight).

1 hour ago, Elp said:

But how much more effort it is to put the larger one on the mount unaided?

This will live on a permanent pier in a dome so it's not such an issue for me. 

Would not want to be setting this up and taking it down each time.

I am swapping over from an 8 inch EdgeHD to a 9.25 inch EdgeHD.

I carefully researched to check sizes and weights, but there were few comparison photos about.

Here are the 2 mid transition.

8 on the way out 9.25 on the way in.

There is a big step up in overall size with the 9.25 despite it only being a little bigger on aperture.

I use a big linear power supply that gives plenty output to power everything and never dips voltage even with the mount slewing both motors at once. 

Multiple outputs, some to run dew heaters that I leave on if it's a damp cold night, (In my dome), to ensure my scope stays dry.

It also runs my LED based lighting both low level marker lights and bright lights when I need them. This includes external path lights.

I found mine used , they come up fairly often.

Very reliable.

EQ6-R (on pier) works very well with an Edge HD8 SCT with OAG and large ZWO camera train. (about 14KG). Guiding is around 0.5 arcseconds on a good night.

(You will probably need a 3rd counterweight)

I piggyback my smaller solar imaging scope on top and that works just as well (solar uses video capture) , that takes it up to around 17.5kg.

I dont try to image with the Edge while the solar gear is piggybacked.

A well known object NGC2237 , or more commonly called "The Rosette Nebula"

Well placed above Fife in Jan 2024 , and we got a rare couple of clear nights so had the chance to collect around 90 subs of 300sec.

GT81 (with 0.8 reducer) and 2600mc camera.

Used PixInsight to bring out the detail of the gas and dust clouds that surround the Orion Nebula.

Taken from above Fife on a rare couple of clear nights in Jan 2024.

GT81 (with 0.8 reducer) and 2600mc camera.

It has been a poor season so far , storm after storm ruining imaging possibilities.

A few clear nights in January however allowed some time with my new 2600mc and GT81 (with 0.8 reducer).

A wide-ish view of the Veil Nebula

Microsoft Word - Top10_NightSky_Objects.doc (rochesterskies.org)

Handy beginers guide of top 10 easy objects to look at.

I have an older AZ-EQ6 without a dedicated USB on board so use the FTDI eqmod cable.

I also have a newer EQ6-R with the onboard USB , so just use that direct with a usb cable.

Can't see any difference in the 2 systems , both work well.

Using both Galilean Moons of Jupiter (shallowsky.com) and Stellarium which does simulate shadow transits if you zoom in , I get a different time for these transits

December 23rd

double shadow begins at 19:09

According to the graphical simulation in Stellarium , the shadow of Ganymede is unfortunately very close to the pole and will be difficult to make out aginst the dark clouds being rather elongated into an elipse.

The shadow of Europa however should be nice and clear much closer to the middle of the disk., and is against a lighter cloud region so stands out better.

Jupiter is around 45 degree altitude for the event (for me) so higher up in less wobbly air for most of the UK.

and for the 30th December

Double shadow begins at 21:45

Again there is one shadow close to the pole against darker cloud , and the second shadow (Europa) will show against lighter cloud bands.

This event happens while Jupiter is at a lowish altitude when viewed from UK (alt 35 degree for me).

This means the clarity will be poorer than for the 23rd event which is when Jupiter is  higher in the sky and so should be in clearer air.

Just need those pesky clouds to stay away.

Below is an image I took of 1st December 2023 of a shadow transit (Io)

Seeing was poor but you can make out the shadow , the red spot to the right of it , and the moon just exiting from the transit across the face of Jupiter to the right of that.

Seeing wasn't great and Jupiter was also still very low from my location, but managed to view the shadow move rapidly across the disk.

From the clear sky over Fife tonight.

Edge HD8 (reduced).

and a later image (lower in wobbly air) , this time HD8 with 2x Powermate

Simple answer is yes.

Anything that can move position will cause errors , always make sure everything is well tightened up , not to the point of damage , but should have no movement.

That said I dont expect a short time like 2 minutes would be likely to move the mount enough for the bar to suddenly slip position , not on every sub at least, more likely to only cause a shift every so often.

To see a drift after only 15 seconds suggests there may be some othe cause.

What method were you using to polar align?

I dont set up each day as I now have a mount on a pier , but in the past I have misidentified an alignment star and so had a lot of drift after alignment.

My error made the mount think it was well aligned when it fact it was nowhere near the celestial pole.

Does that mean you can't rotate the camera though?

In one sense yes, the camera becomes fixed.

However you can actually rotate the wedge diagonal round in the scope focuser , which effectively rotates the image orientation round on the sensor.

I removed the clicklock when connecting direct to my camera (ZWO).

The adapter need is this one.

Baader #27 to fit DSLR to Herschel or Maxbright Diagonal | First Light Optics

this significantly reduces the backfocus used up by the wedge system and allowed me to get to focus with several of my scopes that would not work with the clicklock in place.

(Note currently out of stock at FLO)

Best 100 frames from 3000

Captured with

127mm triplet refractor 950mm, Baader Coolceramic Herschel, and baader continuum filter. ZWO ASI585mc and 2x Powermate

50 best frames from 10,000 , an indication of just how bad the seeing is since the rest were rubbish.

Even so there is still a stacking artifact in the middle

Out of 10,000 frames taken I only stacked 14 of them for this image. Usually I stack 200 but the conditions were awful.