Imaging rig

[Jpr78]

Meade LXD55 SN10. Original GEM is far off from being able to support imaging. I am absolutely married to the idea of using this scope for imagine (can’t go wrong with all of that light gathering capability on top of being f4). So here is my dilemma, my budget is about $2500 and this GEM needs to be rock solid. I will be using a D750 for imaging, no guide scope (I’m a rebel).

[johninderby]

The SN10 OTA is about 15kg and  940mm long so is going to require a substantal mount for imaging. 

[Jpr78]

13 minutes ago, johninderby said:

The SN10 OTA is about 15kg and  940mm long so is going to require a substantal mount for imaging. 

I will assume something with at least 90lb payload? I am starting to think a whole new imaging setup (mount, refractor, filters etc. etc.) will still be much less expensive than just the mount to support the OTA I already have. Any recommendations for a mount for it? I looked at the LXD850 mount and 7k is a massive stretch.

Edited May 20, 2020 by Jpr78

[wimvb]

Does it have to be Meade? Capacity wuse an eq8 or maybe even an eq6R could do the job for substantially less money. 

[Jpr78]

1 hour ago, wimvb said:

Does it have to be Meade? Capacity wuse an eq8 or maybe even an eq6R could do the job for substantially less money. 

It does not have to be Meade.

[Knight of Clear Skies]

4 hours ago, Jpr78 said:

Meade LXD55 SN10. Original GEM is far off from being able to support imaging. I am absolutely married to the idea of using this scope for imagine (can’t go wrong with all of that light gathering capability on top of being f4). So here is my dilemma, my budget is about $2500 and this GEM needs to be rock solid. I will be using a D750 for imaging, no guide scope (I’m a rebel).

I'd suggest taking a step back and thinking again, given your budget its highly probable you could achieve far more with a smaller scope. Starting with too big a scope is a common regret for people looking to get into imaging. Searching on Astrobin there are very few images on there taken with an LXD55 SN10.

I'd recommend having a quick browse of this thread, the 130pds is designed as an imaging scope. Despite its small size and low cost it's more focal length than many people would want to take on. In the right hands it's capable of taking truly great images.

4 hours ago, Jpr78 said:

can’t go wrong with all of that light gathering capability on top of being f4

It sounds good in theory but without accurate guiding it's highly unlikely you'd be able to make full use of the focal length on offer. Also, does the LXD55 image circle cover a full frame camera? (Does it reach infinity focus without modification? Many scopes don't.)

I had a go at unguided imaging with a reduced ED120 (765mm focal length) the other night, before a battery problem cut my session short. Even with 15 second subs it looks like I'd be throwing away quite a lot of data. But mostly I've been imaging with camera lenses, for example this is Simeis 147 with a 135mm lens. Long focal length isn't required for many targets.

Hope that's some help anyway.

Edited May 20, 2020 by Knight of Clear Skies

[happy-kat]

Is the area you intend to image from exposed, if so you may find too many of any images taken unusable due to having movement. The telescope has the potential to be a big wind sail putting more strain on everything having to be rock solid.

[Jpr78]

I will have to rethink this whole plan. You have all contributed valuable knowledge and experience. Perhaps I’ll keep the sn10 for observing and place my money on something smaller and better suited to not throw disappointment my way. This Lunar shot was taken with the sn10 and a D750. 

[johninderby]

Sounds like a good plan. The SN10 is a nice scope but it’s size and weight means it isn’t ideal for AP with a reasonably priced mount.

Here is a lunar shot taken with an 80mm refractor and smartphone. With a proper astro camera could do a lot better of course.

Edited May 20, 2020 by johninderby

[Knight of Clear Skies]

51 minutes ago, Jpr78 said:

I will have to rethink this whole plan. You have all contributed valuable knowledge and experience. Perhaps I’ll keep the sn10 for observing and place my money on something smaller and better suited to not throw disappointment my way. This Lunar shot was taken with the sn10 and a D750. 

Think that's a good plan. Do you have any lenses for the D750? If your existing mount is motorised you might find they work well with it up to about 200-300mm focal length. Many camera lenses need stopping down a bit (50mm are generally good about f4), but focusing on a star a third of the way in from the edge of frame gives better focus than using one in the centre.

I like the lunar shot, nice detail, contrast and crisp without being over-sharpened. Is that from a stack of images or is it a single frame?

Edited May 20, 2020 by Knight of Clear Skies

[Jpr78]

31 minutes ago, Knight of Clear Skies said:

Think that's a good plan. Do you have any lenses for the D750? If your existing mount is motorised you might find they work well with it up to about 200-300mm focal length. many camera lenses need stopping down a bit (50mm are generally good about f4), but focusing on a star a third of the way in from the edge of frame gives better focus than one in the centre.

I like the lunar shot, nice detail, contrast and crisp without being over-sharpened. Is that from a stack of images or is it a single frame?

I have a 200mm f4 prime , 14-24mm f2.8, and a 50mm f1.8. I also have a celestron C8 w/ SB coating I was thinking of deforking and getting a rail to use on the LXD55 GEM. Perhaps that is a better option for imaging? This is a not so great first attempt at M42 with the 200mm prime. I believe it consisted of 30 images stacked in registax and processed in LR. I have a lot of learning to do about processing and workflow. Also the lunar shot was shot bracketed (5 shots) then HDR merged and processed in LR.

Edited May 20, 2020 by Jpr78

[ollypenrice]

11 hours ago, Jpr78 said:

Meade LXD55 SN10. Original GEM is far off from being able to support imaging. I am absolutely married to the idea of using this scope for imagine (can’t go wrong with all of that light gathering capability on top of being f4). So here is my dilemma, my budget is about $2500 and this GEM needs to be rock solid. I will be using a D750 for imaging, no guide scope (I’m a rebel).

Ooh, careful!  If there is one phrase which will never, ever, apply to astrophotography it is this one. It is an activity in which the main endeavour is stopping things from going wrong!  It is also a very counter intuitive activity in which what one might reasonably think to be the case is not the case...

Olly

Edited May 20, 2020 by ollypenrice
typo

[Knight of Clear Skies]

21 hours ago, Jpr78 said:

This is a not so great first attempt at M42 with the 200mm prime. I believe it consisted of 30 images stacked in registax and processed in LR.

That's a good start on M42, what was the exposure time please? I'd recommend Deep Sky Stacker, Regisax is more geared up towards planetary imaging.

21 hours ago, Jpr78 said:

I also have a celestron C8 w/ SB coating I was thinking of deforking and getting a rail to use on the LXD55 GEM. Perhaps that is a better option for imaging?

At 2,000mm focal length or 1,260mm with the reducer it would be very challenging without a beefy mount and well-tuned guiding.

This event on Sunday might interest you. The presenter is Steve Richard, his book on imaging is often recommended by forum members. 

Edited May 21, 2020 by Knight of Clear Skies