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Tbear
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I just watched your awesome video tutorial on your software. I'm about to drop a whole bunch of money on a scope and camera to do some deep sky imaging. My research suggests that the Canon 6D Mark ii is a good camera ( in the price range I can afford ). Would you have any hesitation buying this one or would you recommend a different one in the same price range.

I will definitely be buying your software once the camera arrives... 

 

Thanks

 

Ted

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One caution about the 6D Mk II is that it has a full frame sensor and you need to make sure that whatever scope and focuser you purchase can fully illuminate it. A 2" diameter focuser typically won't do that.

No BYE features have disappeared since the video was shot, but many new features have been added and the program screens have changed.

Whatever camera you decide on, be sure that it is in the BYE Supported Cameras table via the link in the page footer of this page. The newest models create .CR3 raw images, so before purchasing the camera be sure that your processing software can handle the newer RAW format.

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If the sole purpose of the Camera will be Astrophotography, then you should be looking at either the "Prosumer"-line of APS-C Mirrorless Cameras.  Being careful to limit yourself to only those Fully Supported by BYE - M6 and M50 and M200.

If, even after taking Rick's warning about Full-Frame Sensors requiring Highest-level Optics, you still want to pursue a Full-Frame Camera then look to the EOS Ra.  The IR-Filter adaptation for better Ha Emission response makes it the Best current Canon Camera for AP Imaging.

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Thanks so much for your advice. On back order is a Celestron CGEM 9.25 scope having 1.25 eyepiece. I purposely wanted a full frame camera but I’m not sure how to access the comment about not filling it’s full frame. How would I go about knowing if this works?

Unfortunately, the EOS Ra and other mirrorless cameras are out of my price range albeit I did look at them and would love to have one. 6d Mark ii is supported by BYE - I checked. 
 

At the moment I don’t have any imaging software except Photoshop Elements from about 10 years ago. I’ll be sure to check compatibility before investing investing in software. 
 

Again, thanks to everyone for their advice. I’m trying to not make any serious blunder as I put this system together. Please expand on my ‘ full frame ‘ question. 
 

Ted
 

 

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I use my C9.25 with my APS-C DSLRs.  There was a minor amount of Vignetting in the very corners.  I never figured out whether this was due to the SCT Camera Back (default is the Celestron #93633) or the T-Ring (Celestron #93419), or the Baffle Tube inside the C9.25.

These parts are here:  https://smile.amazon.com/Celestron-T-Adapter-9-25-Black-93633/dp/B07TMD2CW8/

Scanning Cloudy Nights shows a few threads where users are running Full-Frame Cameras.  They do report some Vignetting, but most address this with Flats.  A few reference using a M48 "Wide" T-Ring, but none explain where they find a M48 version of the SCT Camera Back.

So, it seems "Doable" to use a 6D Full-Frame on your C9.25...

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3 hours ago, Tbear said:

At the moment I don’t have any imaging software except Photoshop Elements from about 10 years ago. I’ll be sure to check compatibility before investing investing in software. 

An old version of PS Elements is unlikely to support the newer CR2 files produced by the 6D mk II.  Adobe might support these CR2 files through the free Adobe Camera RAW app, but you really need to be working (Calibration/Stacking) with original not Debayered RAW Data.  This is actually where DeepSkyStacker comes in - and DSS v4.2.x does support ALL of the CR2 and most CR3 formats.

If it is Planetary and Lunar Video Imaging you wish to do, you will need to use the conversion software that comes with the 6DmkII (ZoomBrowser?) to convert to AVI format before you can feed to AutoStakkert3 or RegiStax6...

And for the Stretching and Saturation done in Post Processing, if your old PS Elements doesn't support 32/16-bit TIFF, then the freeware GIMP v2 supports both the RAW and the TIFF formats and has most the functions and GUI of the full-blown Photoshop.  https://www.gimp.org/downloads/

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Here are some random comments, in no particular order:

I think that perhaps you could benefit from additional price comparison shopping for a camera. The mirrorless M50 ($579)  and M6 MK II ($849) are considerably cheaper than the 6D Mk II ($1400) when purchasing the body only. All prices from Amazon.com.

You should ask reputable telescope vendors about how well a full frame DSLR will work with a C9.25. You could also do some keyword internet searches. Here is a link to a discussion on Cloudy Nights that may be useful --> https://www.cloudynights.com/topic/684351-camera-sensor-sizetelescope-compatibility/

A full frame sensor is 24x36mm. This makes the diagonal size 43mm or 1.7 inches. So if the image circle is much less than 2" you will have noticeable vignetting that you will need to correct in every image! FYI, adding a focal reducer will reduce the image circle further and making the vignetting worse with a full frame sensor size camera.

If your OTA is an EdgeHD, then per Celestron, "The EdgeHD optics are designed to optimize an image circle 21mm in radius from the center of the field of view. Doubling this figure gives an image circle 42mm in diameter. This is big enough to illuminate a 35mm sensor." They also recommend an APS-C sized sensor camera for use with the 9.25" EdgeHD and the 0.7X focal reducer.

You will also need the 2" visual back for the 9.25. You may also find that learning to image with an F/10 scope will be challenging.

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39 minutes ago, astroman133 said:

Here are some random comments, in no particular order:

I think that perhaps you could benefit from additional price comparison shopping for a camera. The mirrorless M50 ($579)  and M6 MK II ($849) are considerably cheaper than the 6D Mk II ($1400) when purchasing the body only. All prices from Amazon.com.

You should ask reputable telescope vendors about how well a full frame DSLR will work with a C9.25. You could also do some keyword internet searches. Here is a link to a discussion on Cloudy Nights that may be useful --> https://www.cloudynights.com/topic/684351-camera-sensor-sizetelescope-compatibility/

A full frame sensor is 24x36mm. This makes the diagonal size 43mm or 1.7 inches. So if the image circle is much less than 2" you will have noticeable vignetting that you will need to correct in every image! FYI, adding a focal reducer will reduce the image circle further and making the vignetting worse with a full frame sensor size camera.

If your OTA is an EdgeHD, then per Celestron, "The EdgeHD optics are designed to optimize an image circle 21mm in radius from the center of the field of view. Doubling this figure gives an image circle 42mm in diameter. This is big enough to illuminate a 35mm sensor." They also recommend an APS-C sized sensor camera for use with the 9.25" EdgeHD and the 0.7X focal reducer.

You will also need the 2" visual back for the 9.25. You may also find that learning to image with an F/10 scope will be challenging.

You know the expression, “ the more you learn, the more you realize how much you don’t know “ - that’s me. I’m a retired engineer, love computers, photography, and looking forward to my new hobby of astrophotography.
 

Understand that my goals and budget will limit the quality of my images and are unlikely to show up in magazines - and that’s ok. However, with guidance from you and others to at least point me in the right direction, I hope to avoid making a serious blunder in my initial investment - and it seems like I might be looking at the wrong camera for my scope ( which is on back order ). 
 

I’m going back to the drawing board on cameras - thanks to all of you. Other recommendations are welcomed and encouraged. 
 


One  more question - you mentioned my needing a “ visual back ‘  for this scope  Are you referring to the need for the eyepieces to be 2 inches instead of 1.25 which is what comes with it? I’m a bit confused on that comment...

By the way - 
The Celestron support site under pros and cons of various kinds of scopes had this to say about SCR  scopes. “ Unlike large APO refractors or EdgeHD scopes, SCTs cannot correct a full-frame-size DSLR or CMOS sensors (43mm diagonal) and are better for APS-C (28mm diagonal) and smaller sensors”  - supporting exactly what you folks are suggesting. 

To be continued...

Thanks again.

Ted

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1 hour ago, s3igell said:

An old version of PS Elements is unlikely to support the newer CR2 files produced by the 6D mk II.  Adobe might support these CR2 files through the free Adobe Camera RAW app, but you really need to be working (Calibration/Stacking) with original not Debayered RAW Data.  This is actually where DeepSkyStacker comes in - and DSS v4.2.x does support ALL of the CR2 and most CR3 formats.

If it is Planetary and Lunar Video Imaging you wish to do, you will need to use the conversion software that comes with the 6DmkII (ZoomBrowser?) to convert to AVI format before you can feed to AutoStakkert3 or RegiStax6...

And for the Stretching and Saturation done in Post Processing, if your old PS Elements doesn't support 32/16-bit TIFF, then the freeware GIMP v2 supports both the RAW and the TIFF formats and has most the functions and GUI of the full-blown Photoshop.  https://www.gimp.org/downloads/

Thanks for the lead on GIMP. I have seen it referenced in things I have read but haven’t looked into it yet. I’ve used AutoStacker and Registax on some iPhone videos taken through a 100mm spotting scope just to familiarize myself with the process but haven’t tried DSS much less PixInsight. 
 

Ted
 

Ted

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No, with regard to my comment about needing a 2" visual back. It has nothing to do with eyepieces.

Typically, you get a diagonal with the SCT that screws onto the rear cell of the scope. With my old EdgeHD 8", that diagonal only takes 1.25" eyepieces, but for photography, you need to remove the diagonal and replace it with a Celestron to 2" adapter. On one end it has threads to screw onto the rear cell of the SCT. The other end accepts a 2"  T2 adapter. Onto the end of the T2 adapter you screw a Canon T-ring that the camera attaches to.

The extra diameter of the 2" adapters allow complete illumination of an APS-C sensor.

If you are going to use the C 9.25 visually, you may want to upgrade the diagonal to a 2" version.

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3 minutes ago, astroman133 said:

No, with regard to my comment about needing a 2" visual back. It has nothing to do with eyepieces.

Typically, you get a diagonal with the SCT that screws onto the rear cell of the scope. With my old EdgeHD 8", that diagonal only takes 1.25" eyepieces, but for photography, you need to remove the diagonal and replace it with a Celestron to 2" adapter. On one end it has threads to screw onto the rear cell of the SCT. The other end accepts a 2"  T2 adapter. Onto the end of the T2 adapter you screw a Canon T-ring that the camera attaches to.

The extra diameter of the 2" adapters allow complete illumination of an APS-C sensor.

If you are going to use the C 9.25 visually, you may want to upgrade the diagonal to a 2" version.

Thanks - That’s what I thought. I actually ordered those pieces yesterday. Another question - i know I’m probably wearing out my welcome - but for planetary use if I wanted to put a Barlow between the scope and camera do I need a 2 inch? Celestron sell one that is 1.25 and is sort of multipurpose. It slides into the 1.25 inch “ eyepiece “ slot on the back of the scope and has the threads on the other end for the camera T- ring. You can also just use it in the diagonal for viewing. I’m not sure from your comment how the Barlow will effect the illumination of the cmos.  Again - I’m so grateful for your guidance. I’m trying to learn as much as I can by myself but sometimes these kind of subtle details are hard to search for...

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I suppose it depends on whether a 2" Barlow breaks your bank. 

I will say that I don't have 1.25" anything. My Barlows, cameras, adapters, and eyepieces are all 2". I would not expect that a Barlow would cause vignetting. In fact it is likely just the opposite.

If you use a BYE with a DSLR for "lucky" planetary imaging, you will want good illumination across the sensor. That will allow you to get the planet in the field of view and adjust the zoom box to the planet rather than getting the planet in the center of the FOV. Then use the 5X zoom to give you a fraction of the field of view at the full resolution of the camera.

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22 hours ago, s3igell said:

An old version of PS Elements is unlikely to support the newer CR2 files produced by the 6D mk II.  Adobe might support these CR2 files through the free Adobe Camera RAW app, but you really need to be working (Calibration/Stacking) with original not Debayered RAW Data.  This is actually where DeepSkyStacker comes in - and DSS v4.2.x does support ALL of the CR2 and most CR3 formats.

If it is Planetary and Lunar Video Imaging you wish to do, you will need to use the conversion software that comes with the 6DmkII (ZoomBrowser?) to convert to AVI format before you can feed to AutoStakkert3 or RegiStax6...

And for the Stretching and Saturation done in Post Processing, if your old PS Elements doesn't support 32/16-bit TIFF, then the freeware GIMP v2 supports both the RAW and the TIFF formats and has most the functions and GUI of the full-blown Photoshop.  https://www.gimp.org/downloads/

Thanks for the lead on GIMP. I have seen it referenced in things I have read but haven’t looked into it yet. I’ve used AutoStacker and Registax on some iPhone videos taken through a 100mm spotting scope just to familiarize myself with the process but haven’t tried DSS much less PixInsight. 
 

Ted
 

On 1/26/2021 at 11:37 AM, s3igell said:

If the sole purpose of the Camera will be Astrophotography, then you should be looking at either the "Prosumer"-line of APS-C Mirrorless Cameras.  Being careful to limit yourself to only those Fully Supported by BYE - M6 and M50 and M200.

If, even after taking Rick's warning about Full-Frame Sensors requiring Highest-level Optics, you still want to pursue a Full-Frame Camera then look to the EOS Ra.  The IR-Filter adaptation for better Ha Emission response makes it the Best current Canon Camera for AP Imaging.

 

On 1/26/2021 at 11:37 AM, s3igell said:

If the sole purpose of the Camera will be Astrophotography, then you should be looking at either the "Prosumer"-line of APS-C Mirrorless Cameras.  Being careful to limit yourself to only those Fully Supported by BYE - M6 and M50 and M200.

If, even after taking Rick's warning about Full-Frame Sensors requiring Highest-level Optics, you still want to pursue a Full-Frame Camera then look to the EOS Ra.  The IR-Filter adaptation for better Ha Emission response makes it the Best current Canon Camera for AP Imaging.

Okay - I know this might be heresy for this site but now that I’m looking at camera options which are in the $1000+ range, why wouldn’t I consider a dedicated deep sky cooled camera such as a ZWO ASI294MC? Could you give me the pros and cons of buying a Canon ( or Nikon ) DSLR vs something like the ZWO dedicated one? I surely would appreciate your expertise as I continue to figure out what is best for me. 

Thanks

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25 minutes ago, Tbear said:

Okay - I know this might be heresy for this site but now that I’m looking at camera options which are in the $1000+ range, why wouldn’t I consider a dedicated deep sky cooled camera such as a ZWO ASI294MC? Could you give me the pros and cons of buying a Canon ( or Nikon ) DSLR vs something like the ZWO dedicated one? I surely would appreciate your expertise as I continue to figure out what is best for me. 

The prime advantages for Dedicated AP Cameras are the addition of the TEC Cooling and the lack of Visual-oriented UV/IR and AA Filters.

The prime advantages for DSLR / MILC Cameras are their Dual-Use capabilities and the vast Selections of Photographic Lenses.

There REALLY isn't much of any difference in capability of the Sensors - all of the current Dedicated AP Cameras are based on Sensors which were featured in or failed as Point-Shoot or Consumer-grade DSLR Cameras.

Of course, you won't find a ready equivalent of BYE/BYN for any of the AP Cameras.  BYE/BYN is almost alone in presentation of such a Clean and Organized GUI.  Most of the AP Camera Capture Programs look more like the Control Panel of a Commercial Airliner or Spacecraft.

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5 minutes ago, s3igell said:

The prime advantages for Dedicated AP Cameras are the addition of the TEC Cooling and the lack of Visual-oriented UV/IR and AA Filters.

The prime advantages for DSLR / MILC Cameras are their Dual-Use capabilities and the vast Selections of Photographic Lenses.

There REALLY isn't much of any difference in capability of the Sensors - all of the current Dedicated AP Cameras are based on Sensors which were featured in or failed as Point-Shoot or Consumer-grade DSLR Cameras.

Of course, you won't find a ready equivalent of BYE/BYN for any of the AP Cameras.  BYE/BYN is almost alone in presentation of such a Clean and Organized GUI.  Most of the AP Camera Capture Programs look more like the Control Panel of a Commercial Airliner or Spacecraft.

Thanks - agree - but had to ask. I’m going to have enough of a learning curve to deal with involving this entire hobby but at least have a comfort level already with DSLRs. I have read elsewhere that unless you go with monochrome and filter wheels, a dedicated AP lower end color camera is likely to be comparable to DSLR. No way I want to get into filter wheels and  more multiple exposures at this time.  I can’t shoot from my house so my field work  is all portable with limited time.  Thanks for your prompt response and continued guidance. 
 

Ted

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Do realize that if you truly get hooked on AP Imaging, there will likely be one (or several) Dedicated AP Cameras in your Future.

But as a Starting Point, DSLRs aren't all that far behind Dedicated AP Cameras in any element except Cooling.  You will learn to respect the need to be aware of Sensor Heating as you progress in this hobby - but it won't need to be an Obsession.

If the concern about Imaging in your own Backyard is Light Pollution, there are a number of LP Filters which can subdue LP to the extent that you can make significant progress before truly needing to head for Dark Skies.  If the concern is Lack of a Yard or Obscuring Trees and Buildings, neither I nor a Filter can help you...

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I know that it may be a budget buster, but why do you think that a single camera is suitable for all your needs, current and future?

Most people think/feel that getting started with astrophotography with a DSLR, that they may already be familiar with, is a good starting point. This is despite the lack of Hydrogen Alpha sensitivity or cooling. I have friends that do amazing imaging with DSLRs. One uses a T5i and the other sold a 7D Mk II to buy an R6.

It is hard to compare say the M6 Mk II to the ASI294. The M6 has way more, smaller pixels than the 294. Whether that is useful or not depends on a comparison between resolution of your imaging system and your typical seeing. If your seeing is habitually poor to OK, the the smaller pixels are probably not buying you anything. But the DSLR is more easily used for other types of imaging, like solar, lunar, or widefield. The tradeoffs are kind of like deciding to buy a table saw and then after you have used it for a while you also see value in having a band saw, a chop saw, and a circular saw, as well, for other cutting tasks.

My point is this...Rather deciding on which of two very different cameras would be the best to purchase, perhaps you should do the same thing with regard to your choice of telescope (as long as it is still backordered). I think that a faster refractor would be easier to image with and initially more satisfying.

Of course the conventional wisdom is that you should always put your money in the mount...decisions decisions.

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Another newbie question. 
 

In anticipation of getting a canon DSLR, ( likely the M6 Mark ii ) I ordered a Celestron T adaptor ( 93633-a ) and the 93914 T- Ring for the camera. The T ring has some internal threads inboard from the bayonet mount. Is that where I would put a 2 inch filter if I were to use one? I can’t seem to get a straight answer from google searches and there is no mention of these threads in the T- Ring description. I don’t have any filters ( yet ) to try it.

Thanks ( again )

Ted

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If your T-ring is like mine, those threads are not for filters. The diameter is too small for a 2" filter. Instead I think that those threads are how the front and the back of the T-ring thread together.

If you want to add a filter to your setup, I would suggest that you ask your vendor for their solution. That way if you get a wrong answer they will be more apt to accept the item for return.

My setup connects to a 2" focuser so I need a 2" T-2 adapter the telescope end of that adapter has internal threads for a 2" filter.

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2 hours ago, s3igell said:

Do realize that if you truly get hooked on AP Imaging, there will likely be one (or several) Dedicated AP Cameras in your Future.

But as a Starting Point, DSLRs aren't all that far behind Dedicated AP Cameras in any element except Cooling.  You will learn to respect the need to be aware of Sensor Heating as you progress in this hobby - but it won't need to be an Obsession.

If the concern about Imaging in your own Backyard is Light Pollution, there are a number of LP Filters which can subdue LP to the extent that you can make significant progress before truly needing to head for Dark Skies.  If the concern is Lack of a Yard or Obscuring Trees and Buildings, neither I nor a Filter can help you...

Thanks - I totally understand that more ‘ equipment ‘ will likely be in my future. As I’ve said before, I’m just trying to avoid making a major blunder with my initial investment. Quite honestly, I can afford anything I want to buy. But the practical side of me says to start reasonably and see what happens....  Although living in a home in The Villages, Fl isn't conducive to viewing because of relatively small lot sizes, there are plenty of places nearby I can get away from the lights with great views of an open sky. 

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2 hours ago, astroman133 said:

I know that it may be a budget buster, but why do you think that a single camera is suitable for all your needs, current and future?

Most people think/feel that getting started with astrophotography with a DSLR, that they may already be familiar with, is a good starting point. This is despite the lack of Hydrogen Alpha sensitivity or cooling. I have friends that do amazing imaging with DSLRs. One uses a T5i and the other sold a 7D Mk II to buy an R6.

It is hard to compare say the M6 Mk II to the ASI294. The M6 has way more, smaller pixels than the 294. Whether that is useful or not depends on a comparison between resolution of your imaging system and your typical seeing. If your seeing is habitually poor to OK, the the smaller pixels are probably not buying you anything. But the DSLR is more easily used for other types of imaging, like solar, lunar, or widefield. The tradeoffs are kind of like deciding to buy a table saw and then after you have used it for a while you also see value in having a band saw, a chop saw, and a circular saw, as well, for other cutting tasks.

My point is this...Rather deciding on which of two very different cameras would be the best to purchase, perhaps you should do the same thing with regard to your choice of telescope (as long as it is still backordered). I think that a faster refractor would be easier to image with and initially more satisfying.

Of course the conventional wisdom is that you should always put your money in the mount...decisions decisions.

Thanks. I appreciate your advice. Keeping in mind portability ( a must have for me ) the Celestron CGEM 9.25 SCT that is on back order has a 40lb mount, 20 lb tube, and 20 lb tripod. I’m 73 in good shape but don’t want to be lifting much more than 40lbs. And it’s unlikely I will get any younger.  What kind and size of refractor would you buy if you were in my shoes. I am open to explore everyone’s opinion which is why I’m on this forum with all you great folks.  If I use a field reducer on my f10 it brings it down to an f6 I seem to recall... I remember you commented above about imaging with an f10 being ‘ challenging ‘ . I’m more than happy to listen more to your concerns while I still have a chance...

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You may want to look at a William Optics GT81. My friend has one and it is optically wonderful. It has a focal ration of f/5.9. With the M6 Mk II and its APS-C sized sensor it would give you a 3x2 degree field of view and a resolution of 1.38 arc-seconds/pixel. It would also weigh about the same as the SCT. It comes with the smaller Vixen dovetail, so you might need an Losmandy-Vixen adapter, because I believe that the Celestron mount has a Losmandy dovetail saddle. I bought a dual saddle for my CGEM from ADM accessories in Buffalo, NY. 

I would suggest contacting OPT in California. They can also tell you what accessories you would need for AP, what type of finder to use, etc. Another thing for long duration astrophotography is autoguiding and you need to think about how to do that. Options are an off-axis guider and guide camera or a piggyback guide camera. You may already have that handled, because you would heed it with the C9.25 as well.

If you are interested, let me know and I can ask my friend what he uses. BTW, I haven't purchased from OPT in a while, but they used to give you a modest discount if you belong or plan on joining an astronomy club. If they still offer the discount, then I would give them the name of a local club that you plan on joining.

I hope this helps and is not too overwhelming or too pricey.

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52 minutes ago, astroman133 said:

You may want to look at a William Optics GT81. My friend has one and it is optically wonderful. It has a focal ration of f/5.9. With the M6 Mk II and its APS-C sized sensor it would give you a 3x2 degree field of view and a resolution of 1.38 arc-seconds/pixel. It would also weigh about the same as the SCT. It comes with the smaller Vixen dovetail, so you might need an Losmandy-Vixen adapter, because I believe that the Celestron mount has a Losmandy dovetail saddle. I bought a dual saddle for my CGEM from ADM accessories in Buffalo, NY. 

I would suggest contacting OPT in California. They can also tell you what accessories you would need for AP, what type of finder to use, etc. Another thing for long duration astrophotography is autoguiding and you need to think about how to do that. Options are an off-axis guider and guide camera or a piggyback guide camera. You may already have that handled, because you would heed it with the C9.25 as well.

If you are interested, let me know and I can ask my friend what he uses. BTW, I haven't purchased from OPT in a while, but they used to give you a modest discount if you belong or plan on joining an astronomy club. If they still offer the discount, then I would give them the name of a local club that you plan on joining.

I hope this helps and is not too overwhelming or too pricey.

Thanks a bunch - I’ll take a look into this.... and yes, I’m aware of guiding.... just haven’t tackled that one yet!

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19 hours ago, Tbear said:

Thanks. I appreciate your advice. Keeping in mind portability ( a must have for me ) the Celestron CGEM 9.25 SCT that is on back order has a 40lb mount, 20 lb tube, and 20 lb tripod. I’m 73 in good shape but don’t want to be lifting much more than 40lbs. And it’s unlikely I will get any younger.

I hear you...  I'm not all that far behind you...

Realize that the CGEM (or any equivalent EQ Mount suitable for AP Imaging) has a Combined Weight of 80-100lbs - even if the largest single part is the 40lb Head.  (You forgot to factor in the 15-35lbs of Counterweights and the 20-40lbs for the Field Battery / Power Source.)  The flip side is that all this Weight adds to Rig Stability - a critical component once you ramp-up your AP Imaging Rig and Skills.

My trick is a good Folding Hand Truck (well, I have 2x - one that is the IT/Salesman style lightweight folding aluminum for when I'm taking my smaller vehicle for an evening setup in a Park; and a full-blown Convertible Hand Truck for when I'm taking the Pickup for a Weekend or more and know that I have a bit of "wild" to traverse with my gear).  Yes, you will still have to hoist everything in/out of the vehicle, and onto the Tripod, but why schlep 100-200lbs of gear when man has already invented the Wheel??

(Oh, and in my Real Life, I am the Central Florida source for Industrial/Commercial-quality Hand Trucks...)

If, instead of involving your vehicle to drive a few miles out of town, all you are doing is a trek to the Park at the End-of-the-Block, then there is another Option:  a Scope Buggy or JMI Wheeley Bars.  With either of these, you leave the Scope fully assembled in your garage, and simply pull it out and set the "feet".

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18 hours ago, Tbear said:

You may want to look at a William Optics GT81.

I'll second the idea of an 80mm or 102mm 3-element APO as a better Starter Scope than the C9.25 for AP Imaging.  Reducing the Focal Length and the Focal Ratio will make for an easier start.  And will give you access to a larger set of rewarding DSO Targets (many would have been too large for the C9.25 even with the 0.63x Reducer).

AutoGuiding will also be a simpler prospect - you won't have to consider an OAG with these Refractors.

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4 hours ago, s3igell said:

I'll second the idea of an 80mm or 102mm 3-element APO as a better Starter Scope than the C9.25 for AP Imaging.  Reducing the Focal Length and the Focal Ratio will make for an easier start.  And will give you access to a larger set of rewarding DSO Targets (many would have been too large for the C9.25 even with the 0.63x Reducer).

AutoGuiding will also be a simpler prospect - you won't have to consider an OAG with these Refractors.

LOL - Good news / bad news - while doing more research this afternoon I was notified my telescope was shipped and arriving Monday. So, at least for the 30 day return period, I’ll be giving the 9.25 a try. 
 

I do realize there is extra weight I must lug around but as long as no one piece is too heavy I’m okay with that. I do have a hand truck ( not folding ) and a collapsible red wagon we lug stuff in for the beach and grandkids sporting events so my wife and I are pretty good at finding ways to move things. Lots of room in my Highlander too. 
 

One thing I can’t bring myself to do is pay $500 for a foam case to keep the OTA in. I’ll make sure it’s cozy in something.... I’ll get creative. 
 

I am sure I’ll have lots of questions as I get things up and running.l..

Ted

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16 hours ago, Tbear said:

One thing I can’t bring myself to do is pay $500 for a foam case to keep the OTA in. I’ll make sure it’s cozy in something.... I’ll get creative. 

For the short-term, you can always use the Shipping Box (assuming that it survived the "tune-up" performed by "Drop-Kick Express").  It assumedly protected the Precious Contents on the Journey across China, the Pacific Ocean, and the Wilds of USA.

(If this is a "Keeper", the Florida Humidity will necessitate "creativity" such as "Waterproofing-by-Packing-Tape"...)

You can look to Northern Tool and even Harbor Freight - each of whom has Private Label knock-offs of Pelican Cases at 1/2-1/3 Cost.

Good Luck...

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Keep in mind that the field-of-view with the 9.25" SCT is small enough that your exposures will need to be long enough that autoguiding will be very important/mandatory. Also as s3igell has said that at that focal length you would need an off-axis guider solution to get acceptable guiding.

I also agree to use the shipping box when transporting the OTA, at least at first.

Good luck with the new scope.

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5 hours ago, astroman133 said:

Keep in mind that the field-of-view with the 9.25" SCT is small enough that your exposures will need to be long enough that autoguiding will be very important/mandatory. Also as s3igell has said that at that focal length you would need an off-axis guider solution to get acceptable guiding.

I also agree to use the shipping box when transporting the OTA, at least at first.

Good luck with the new scope.

Thanks. I’ll need all the luck I can get. The learning curve has been very steep for me the last several weeks and I haven’t even had a scope to work with.... I tend to ‘ binge ‘ learn when I get interested in something  

I haven’t researched guiding yet although I know it’s needed. Your comment about needing off-axis guiding caught my eye... is there a reason off-axis would be preferable to an auto guide on top of the scope for my situation?

Thanks.... 

Ted

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There are two reasons:

1) the other option to an off-axis guider is to piggyback a small scope on the main scope and attach a guide camera to it. The problem is the inevitable independent movement of the two scopes gives rise to what is called differential flexure. This means that your guiding could be spot on, but you still see evidence of bad guiding (elongated stars) in your images.

2) Whatever you get for guidescope is going to be much shorter focal length than the imaging scope. Some sample numbers may help. The focal length of the 9.25 is 2350mm. This is the scope that you are imaging with and you want those images to have perfectly round stars.  The guide scope may be more in the 300-400mm focal length. It is quite a lot to expect to be able to correct the movement using a scope with 15% of the focal  length that you are imaging at. So again, some numbers. Assuming that the guide camera and the imaging camera have pixels that are the same size, a one pixel movement in the guider could be a 5-7 pixel movement in the imaging train.

Ideally you could simply get a guidescope with a longer focal length. The problem then is that the mount has to carry the additional weight of the longer and heavier guidescope. Also, with the longer guidescope, you will tend to have more of a problem with differential flexure.

As an example, before computers, professional astronomers used to spend the entire night sitting behind a large telescope while exposing a photographic plate. The performed the guiding manually while looking through an eyepiece of the guidescope and making subtle adjustments to keep both scopes properly pointed at the target area. In order to detect unwanted movement, the guidescope had a longer focal length than the imaging scope.

With a short focal length guidescope the guide camera may not even see the movement that is driving you crazy in your images. So, with longer focal length telescopes it is more common to use an off-axis guider. The off-axis guider has a pick-off prism that is inserted into the light cone from the scope, but does not block the light going to the imaging sensor. That way you are guiding at the same focal length as you are imaging at and eliminating differential flexure.

The downside to using an off-axis guider  is that the pick-off prism is very small and at the longer focal length it can be difficult to find a star to guide on. Many off-axis guiders allow you to rotate the guide camera around the sensor in order to assist with finding a guide star. When I image with a dedicated, monochrome camera I use its built-in off-axis guider. My 5" refractor's focal length is 660mm and I always have several guide stars to choose from, but with your longer focal length of your SCT, it will be challenging.

Remember when I said that imaging at f/10 would be difficult!

 

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6 hours ago, astroman133 said:

There are two reasons:

1) the other option to an off-axis guider is to piggyback a small scope on the main scope and attach a guide camera to it. The problem is the inevitable independent movement of the two scopes gives rise to what is called differential flexure. This means that your guiding could be spot on, but you still see evidence of bad guiding (elongated stars) in your images.

2) Whatever you get for guidescope is going to be much shorter focal length than the imaging scope. Some sample numbers may help. The focal length of the 9.25 is 2350mm. This is the scope that you are imaging with and you want those images to have perfectly round stars.  The guide scope may be more in the 300-400mm focal length. It is quite a lot to expect to be able to correct the movement using a scope with 15% of the focal  length that you are imaging at. So again, some numbers. Assuming that the guide camera and the imaging camera have pixels that are the same size, a one pixel movement in the guider could be a 5-7 pixel movement in the imaging train.

Ideally you could simply get a guidescope with a longer focal length. The problem then is that the mount has to carry the additional weight of the longer and heavier guidescope. Also, with the longer guidescope, you will tend to have more of a problem with differential flexure.

As an example, before computers, professional astronomers used to spend the entire night sitting behind a large telescope while exposing a photographic plate. The performed the guiding manually while looking through an eyepiece of the guidescope and making subtle adjustments to keep both scopes properly pointed at the target area. In order to detect unwanted movement, the guidescope had a longer focal length than the imaging scope.

With a short focal length guidescope the guide camera may not even see the movement that is driving you crazy in your images. So, with longer focal length telescopes it is more common to use an off-axis guider. The off-axis guider has a pick-off prism that is inserted into the light cone from the scope, but does not block the light going to the imaging sensor. That way you are guiding at the same focal length as you are imaging at and eliminating differential flexure.

The downside to using an off-axis guider  is that the pick-off prism is very small and at the longer focal length it can be difficult to find a star to guide on. Many off-axis guiders allow you to rotate the guide camera around the sensor in order to assist with finding a guide star. When I image with a dedicated, monochrome camera I use its built-in off-axis guider. My 5" refractor's focal length is 660mm and I always have several guide stars to choose from, but with your longer focal length of your SCT, it will be challenging.

Remember when I said that imaging at f/10 would be difficult!


 

Thanks for your in-depth and clear explanation. It makes perfect sense. Until I get some experience under my belt, I will try to find some easy and bright stuff to photograph. I do plan to use a corrector/reducer to lower it to F/6 and widen the field of view. I’ve got a lot to learn but since a guide scope system is a must, I will likely get one sooner rather than later. 
 

I really appreciate you taking the time to explain all of this to me .  I’m trying to learn as much as I can on my own but there is no substitute for ‘chatting’ with an experienced person like you and s3igell. 
 

Ted

 

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