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Beginning price-point for EAA/NV?

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#1 drneilmb

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Posted 12 March 2018 - 10:29 AM

I posted this as a reply to a post in the Eyepieces forum, but I wanted to ask it more directly here: At what price-point does it make sense to buy EAA or NV gear rather than a bigger telescope?

 

For me as a new hobbyist working my way up, the question in my mind is always how best to invest my next N dollars to increase my astronomy enjoyment. Of course, the answer depends on my observing environment (my dark rural yard), the equipment I already have, and the value of N.

 

  • When I had nothing and N=150, I built a 4.5" f/8 reflector. I don't think that there was any way to do NV or EAA at that price point.

 

  • To get better DSO performance and satisfy my aperture fever, when I saved up N=300, I built an 8" f/6 dob. I don't think there are any NV possibilities at that price, but some of the cheapest ETX/Nexstar EAA setups might come into play

 

  • I enjoy telescope building and with my next N=500, I'm building a 12" f/5 dob. I'm very excited about what it can do, but I can see where I could have instead put that money into a 6SE/R2 setup. I have a preference for less computers in my observing, so I'm comfortable with that choice, but other people could reasonably have made the other choice.

 

  • Once I have a 12" dob and a handful of mid-range eyepieces, then N=500 won't get me close to NV, so maybe it's best to get some premium eyepieces? Or maybe I can make an equatorial platform and get an R2 to start doing video astronomy with that telescope? These are the decisions I will be making in a couple months.

 

But then, once I have a 12" dob and a couple nice, wide-angle eyepieces, then I think that the next step up is about N=3000 for making a 20" dob.  At that point, that's a very heavy, very expensive scope and then it feels like maybe NV makes a whole lot of sense. I think that $2-3000, might be the minimum price where I can see NV being a better choice than larger telescope.

 

Given the large initial expense that image intensifiers require, where do you think that the sweet spot for getting into NV or EAA is?

 

When I read here about NV, it seems like you've already tried one of every kind of telescope before, but where is image intensification in the cost-benefit landscape for brand new hobbyists? If you didn't already have all the equipment you have, when would you have started adding EAA or NV gear?

 

Thanks in advance for any perspective you can share,

 

-Neil



#2 TOMDEY

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Posted 12 March 2018 - 11:23 AM

Hi, Neil, Another qualifier is that Night Vision is substantially different than increasing aperture. Some of the claims are pretty optimistic, marketeerish. Very Good NV can be had for around $1500. For me, it improves mag limit by almost a magnitude, no more than that. One would then argue that's equivalent to increasing your aperture by ~40%. Thing is, NV enhances some stuff, but fails on others. NV is very red/NIR responsive, but the GaAs photocathode is almost dead in the blue. I keep NV eyepieces right there beside the other ~regular~ ones. PS: When I'm doing "trade studies" regarding what to maybe gift myself... I do a lot of research and then... go with what I intuitively wanted in the first place! Even people who crank the financial optimization analysis... always settle on what they wanted beforehand! I've seen this in business for decades: Knowing what you want, and then do the analysis that magically concludes that's what you SHOULD buy!  PS: We need to put a man on Mars? Tom


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#3 t_image

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Posted 12 March 2018 - 06:56 PM

  • multi-use equipment=best return on investment

A point I was happy to discover,

without finding any guidance towards this in the visual and EAA realms,

is the value-savings gained from multi-use equipment.

 

A reflector scope and eyepieces are nice, but you pretty much can only use them for astronomy. IMO it is a little too metaphorically myopic for my investments. Especially if one doesn't live in a location that has clear skies more than not, and if you aren't a fan of lunar or solar, then the amount of days per year used per $$$ is quite costly.

 

A benefit the AP world lends towards the conversation is the utilization of normal photographic equipment.

I know it is a rather particular model,

but the Sony a7s plus some nice photography lenses has allowed me to do EAA easily and at the same time has served even more often a valuable tool in normal daytime photography and video uses.....

  • the one you will most often use will give the best return on investment

I can easily take my a7s out with a 85mm f/1.4 lens handheld and it might as well be NV compared to any other handheld binos. I can pull my f/4 500mm and a 3x teleconverter out of a backpack, throw it on a collapsible tripod, and go to town just as easily.....

 

I appreciate the versatility of the NV gear I see people reporting about, because so often they aren't weighed down to some giant rig that you need for visual aperture or EAA live stacking with steady tracking.....

And if you do feel like taking the time to set up a large rig,

then NV just becomes a force multiplier.....

 

Given different equipment offers various thresholds of complexity,

but if one gets to a point that the setup of the mount and scope becomes more burdensome than not,

or taking that laptop out and getting all the software and camera drivers to consistently work ends up being a drag,

then the calculus of time used and enjoyment had out of NV goggles or the like quickly tips the scale towards a better investment.

 

  • Ability to view sky objects on nights with less-than-clear skies

Similar to the above the gear you will use is the best gear to get,

gear like NV that offers a quick setup and immediately amplification,

allows one to do more viewing on partly cloudy nights and even when visually the sky seems overcast.....

 

for example:

meteor in clouds:

meteor in the clouds
satellite in clouds:
satinclouds

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#4 chemisted

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Posted 13 March 2018 - 06:21 AM

I have been doing NV astronomy for over 15 years and got my first device shortly after my first telescopes so maybe this will help.  I purchased the Collins I3 specifically because I was (and still am) very interested in resolving globular clusters (see my article in July 2017 S&T).  This enabled me to stay with an aperture of 10" that involved easy setup and breakdown as I have never had an observatory.  On these targets I easily get 2X to 3X aperture increase.  The initial investment has paid for itself many times over in shear enjoyment of dozens and dozens of fully resolved globulars.  Fast forward to 2017 when I acquired my second NV device - a top end NVD Micro on the used market from a trusted CN user.  Now, with an H-alpha filter, I have incredible views in real time that match long exposure imaging of extended nebulae.  Just the device and old manual photography lenses do the trick.  While I have always kept my glass eyepieces for planetary and double star observing I find I am using them less and less these days as the NV approach offers so rich a harvest of incredible views.


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#5 Eddgie

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Posted 13 March 2018 - 08:40 AM

Even the finest, widest field eyepieces made are not going to close the gap on EAA or Night Vision astronomy because the eyepeice feeds what is (by comparison) a very poor detector, which is the human retina.   No eyepiece you use can overcome its limitations.  It has horrible red sensitivity and restricts you to a 7mm exit pupil (at best).  It does not matter how fine the glass is, how perfect the coatings are, or how wide the apparent field of view is because your eye was, is, and will always be the limit to the system.

 

 

The answer to your question will all be subjective because only you can make that final decision about at what price point things make sense.

 

Both EAA and Night Vision are proven performers and people using both methods will give you great testimony that it works.

 

You yourself are providing testimony that what you are doing is not working. 

 

As for me, having owned maybe 50 telescopes and a 100 eyepieces, I would say that Night Vision is without doubt the best money I have ever spent on astronomy gear, and I have done the best ovserving of my life using Night Vision.

 

EAA has a bit lower entry point if you look at the inexpensive systems like R2 and can do amazing things.

 

Both will take you places you can't do with the human eye.  Both have their advantages and disadvantages, but the difference in the end is that one is real time monochrome, and one is a delayed full color image.

 

Both will allow you to vastly exceed what you can do with conventional eyepieces.  I myself have completely stopped using conventional eyepieces for deep space work.    Some still use them though so NV or EAA does not mean you have to completely abandon conventional eyepieces.

 

People have found Gen 3 NV on Ebay for well under $1000.   A great used PVS-7 full kit can be put together for less than $2000.   R2 System for a fraction of that. 

 

If you want the latest and greatest L3 filmless tube in white phosphor, you will spend many thousands, but even a good used PVS-7 will let you see Barnard's Loop, Horeshead Nebula, and much more that you will never see using any conventional telescope and eyepiece made. 

 

Only you can answer the question you have asked though because 10 pages of responses can't really answer that question with any high percentage of certainty. 


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#6 bobhen

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Posted 13 March 2018 - 09:21 AM

Also see my initial response over in the eyepiece forum.

 

Where is the sweet spot for getting into NV…

 

You need to have experience and the basic skills used with conventional observing first. If you have those skills and a telescope and you are looking for you next “larger” telescope (and you have a budget for a larger scope) but the size, packing, unpacking, and repacking, plus the drive to a dark-sky location, and a set of ultra wide eyepieces used for deep sky observing are giving you pause, then you should consider night vision.

 

Yes NV intensifiers are expensive but so are 5 Ethos eyepieces and a 20-inch Dobsonian. And no matter how wide the view, a conventional eyepiece will not show you what an intensifier can. You can rent one to try. But you will need adapters and a .7 Ha filter used for CCD imaging to get the best nebula views and a Pass filter to get the best non-nebula views.

 

If you have the budget, say something around $3,500 to 4,500 with filters, etc. (you can get into NV for less but that is a different discussion) and you already have a telescope, then an intensifier will allow you to see more than the large Dobsonian and a set of ultra wide eyepieces. And you don’t have to drive to a dark site.

 

Of course, if you already have a 10 to 12-inch Dobsonian you might want to add a smaller refractor for wide views. And if you have a smaller refactor, you will want to add an 8 to 10-inch telescope for image scale. And you will still need conventional eyepieces for lunar/planetary viewing.

 

However, it is not just about large versus small or the expense or the convenience. The bottom line is that if you want to see more objects and see them much easier and you want to see the "invisible", "other half" of the universe, then no conventional telescope or eyepiece will show you what a intensifier will. How much is that worth?

 

Bob


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#7 drneilmb

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Posted 13 March 2018 - 11:07 AM

Thanks for your patient responses everyone. I see the great excitement generated by these tools and I want to have that too!

 

NV in particular seems out of reach for a casual, budget-limited hobbyist. I absolutely know that everyone has different parameters and has to make their own individual decisions, but bobhen's $3500 and Eddgie's $2000 are very useful data for me to understand what else is in the same ballpark. It looks like that ballpark is occupied by big (16"+??) dobs and big APO refractors and multiple ultra-wide eyepieces.

 

I like this information because if I ever start dreaming about that 20" f/4 dob, then this reminds me that I should simultaneously be dreaming about image intensification. I know that the capabilities and difficulties are quite different, but from my budget-limited perspective, they live in the same "place".

 

I'd love to hear more of the same kind of answers about EAA. I know of the Evolution R2, but because of discussions of focal reducers and image scale, I'm not totally clear what kind of objects it is competitive on. Can the camera be added to my existing dob with an equatorial platform, or is pinpoint goto required? If goto is required, then where is the entry-level for those systems?


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#8 bobhen

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Posted 13 March 2018 - 12:43 PM

Thanks for your patient responses everyone. I see the great excitement generated by these tools and I want to have that too!

 

NV in particular seems out of reach for a casual, budget-limited hobbyist. I absolutely know that everyone has different parameters and has to make their own individual decisions, but bobhen's $3500 and Eddgie's $2000 are very useful data for me to understand what else is in the same ballpark. It looks like that ballpark is occupied by big (16"+??) dobs and big APO refractors and multiple ultra-wide eyepieces.

 

I like this information because if I ever start dreaming about that 20" f/4 dob, then this reminds me that I should simultaneously be dreaming about image intensification. I know that the capabilities and difficulties are quite different, but from my budget-limited perspective, they live in the same "place".

 

I'd love to hear more of the same kind of answers about EAA. I know of the Evolution R2, but because of discussions of focal reducers and image scale, I'm not totally clear what kind of objects it is competitive on. Can the camera be added to my existing dob with an equatorial platform, or is pinpoint goto required? If goto is required, then where is the entry-level for those systems?

I would seriously consider a video camera like the R2 if you want to see more and price/budget is a consideration. I did video for 15-years before NV and it is thrilling to see photo-like images in 30-seconds.

 

Video feels a little closer to imaging in how you set things up and use it whereas NV is more like visual observing. But if the goal is to see more, video is certainly a viable option.

 

You will generally need a tracking mount that can track for 60 seconds or so. Goto is not needed but nice to have. The sensitivity of the video camera actually makes finding objects without goto easier.

 

A nice scope for video is an 8-inch SCT on a GEM with F3.3 and F 5 reducers. You can shoot at F3.3, F5, and F10. 

 

There is more to it of course, so do some research and video might be a nice, cost-effective alternative.

 

Bob


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#9 Jeff Lee

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Posted 13 March 2018 - 01:32 PM

For me it was the issue with light pollution. Thus the $500 I spent for a ZWO224 and a Refurbished i5/8 gig/256 SSD was much better than selling my house and moving. I did add an ES102 and used ST80.

 

The image scale of the C8 @6.3 and the 224 is really good for planets and deep fuzzies (M82 on my 10" screen with the C8 was amazing with one 14 second exposure). 

 

This was from a Bortel 5/6 sky. 

 

It all comes down to what your needs/goals/wants are. Mine was very simple - how can I increase my Astronomy "fun/joy" for what I wanted to spend. EAA was it, and the equipment I need was only $500 - a cost/benefit buy among the best hobby purchases I've ever made.


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#10 Adun

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Posted 13 March 2018 - 02:04 PM

I wanted to ask it more directly here: At what price-point does it make sense to buy EAA or NV gear rather than a bigger telescope?
 
For me as a new hobbyist working my way up, the question in my mind is always how best to invest my next N dollars to increase my astronomy enjoyment.

  • To get better DSO performance and satisfy my aperture fever, when I saved up N=300, I built an 8" f/6 dob. I don't think there are any NV possibilities at that price, but some of the cheapest ETX/Nexstar EAA setups might come into play
  • But then, once I have a 12" dob and a couple nice, wide-angle eyepieces, then I think that the next step up is about N=3000 for making a 20" dob.  At that point, that's a very heavy, very expensive scope and then it feels like maybe NV makes a whole lot of sense. I think that $2-3000, might be the minimum price where I can see NV being a better choice than larger telescope.
where do you think that the sweet spot for getting into NV or EAA is?

 

Hello Neil

 

For me that sweet spot was $385. I wanted better DSO views than my 114mm F4 reflector and realized what a trap aperture fever was. Being in South America made me very sensitive to shipping cost (read: weight).

 

So my options were importing a 6" OTA ($200) and making a dob out of it myself, or jumping into EAA. I paid $385 for the mount+scope+camera, and one year later I consider it an excellent decision. (more details on this thread). 

 

Let's call it ~$400. At that price point, one gets much more DSO performance from jumping to EAA than from getting a visual scope (which at that price would be an 8" dob). Many won't agree, but that was my experience.

 

Half a year after getting that EAA rig, I still got a 10" dobsonian, because I like visual too. I knew the much more expensive 10" dob would not go as deep as the EAA rig (which still remains my most powerful telescope) but I still wanted a visual light bucket, and 10" was the largest OTA I could lift. It doesn't go as deep but some times I want actual billion-years-old photons in my retina.

 

Even then, a better upgrade for my 10" Skywatcher Collapsible dobsonian would be a $400 equatorial platform to use it for EAA. Or a $2000 NVD. Either would be much more reasonable for me than a 20" dob


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#11 drneilmb

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Posted 13 March 2018 - 02:33 PM

Thank you Adun and Jeff for sharing your experiences. It's exciting to hear about how EAA is competitive with very mid-range dobs. I don't think I will regret my 12" f/5 dob build experience at all, but that definitely affects the way I think about what comes next after this. I've been excited about building an equatorial platform, so I will start thinking about how a video camera could fit in with that project.



#12 bdyer22

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Posted 13 March 2018 - 02:46 PM

I primarily use an AT 80mm EDT refractor and it has pulled in many mag 17 galaxies with a EAA camera.  Orion says its 16" (406mm) Dob has a limiting stellar magnitude of 15.7.  And it has more than 25 times the light gathering ability to boot.  EAA is the great equalizer.  :)
 


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#13 Adun

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Posted 13 March 2018 - 03:56 PM

Thank you Adun and Jeff for sharing your experiences. It's exciting to hear about how EAA is competitive with very mid-range dobs. I don't think I will regret my 12" f/5 dob build experience at all, but that definitely affects the way I think about what comes next after this. I've been excited about building an equatorial platform, so I will start thinking about how a video camera could fit in with that project.

 

You never will regret it. Every amateur astronomer should have something between 10" and 14". It's a human scale telescope, where you can still move it, observe without stairs, etc. 

 

Now, you have a huge advantage being able to build your own ATM scope: For a dobsonian to be most usable for EAA, it needs to have a lot of in-focus. This is because focal reducers move the focal plane inside by quite a bit. Focal reducers are almost required at these focal lengths (1200mm and beyond), because of small sensors (NVDs and CCD/CMOS cameras). Small sensors and long focal length produce too much magnification. Larger sensors are very expensive (and inexistent in the case of NV), so a focal reducer is a better way to get a more useable magnification.

 

That's why I chose a Skywatcher Collapsible dobsonian: I had been doing EAA for a good while, and I wanted a dob useable for imaging, hoping to one day get an EQ platform for the dob and use it for EAA. By being collapsible, the SW has a middle point in the trusses, meant for binoviewing, where you partially collapse it, and the focal plane protrudes out of the focuser. This affords so much in-focus that I can use a 0.5x focal reducer with my EAA camera.

 

Your ATM capabilities would enable you to make a dob optimized for EAA: Faster mirror (F4) and/or shorter focal length, larger secondary, more in-focus for focal reducers. It wouldn't have to be 20"... even a manageably small 8" or 10" could be made excellent for EAA/NV.

 

 

 I primarily use an AT 80mm EDT refractor and it has pulled in many mag 17 galaxies with a EAA camera.  Orion says its 16" (406mm) Dob has a limiting stellar magnitude of 15.7.  And it has more than 25 times the light gathering ability to boot.  EAA is the great equalizer.  smile.gif

 

Indeed, I get stars "not on the maps" with  my 80mm refractor. Can you imagine what a 10" F4.7 dob would do with 20 second exposures?

 

I once placed my IMX224 camera on my dob... had to lower exposure to just 250ms because of lack of tracking, and I got quite a bit of detail from Orion's Huygenian region. From just 250ms exposure!

 

That made me wish I had gotten the goto version of the 10" dob.  ... I'm still looking for a platform, it just turned out to be difficult to get for my latitude (3ºN)

Edited by Adun, 13 March 2018 - 04:05 PM.


#14 drneilmb

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Posted 13 March 2018 - 05:06 PM

 

That made me wish I had gotten the goto version of the 10" dob.  ... I'm still looking for a platform, it just turned out to be difficult to get for my latitude (3ºN)

Adun,

 

Did you see Cyrus's thread where he made a circle-segment equatorial platform for 1 degree north latitude? https://www.cloudyni...ing-scrap-wood/



#15 Relativist

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Posted 14 March 2018 - 01:21 PM

One thing to keep in mind is if you go fast enough with the primary optic, focal reduction becomes optional or in-necessary.

#16 Adun

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Posted 14 March 2018 - 01:42 PM

Adun,

 

Did you see Cyrus's thread where he made a circle-segment equatorial platform for 1 degree north latitude? https://www.cloudyni...ing-scrap-wood/

 

Hadn't seen it, thanks for the tip!



#17 N2KEN

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Posted 19 May 2018 - 06:05 PM

It's interesting to stumble across threads like this while scanning through the forums. This is only a controversial topic for those with a life partner who doesn't see any value in looking up, regardless of the price point.  Investments in astronomy gear are a series of personal choices and require thought, research, constraint and significant dollars. All these purchases are discretionary.

 

Over the past several years I've spent a few dollars on needless items. These were mostly things I thought I needed or that would enhance my viewing experience. My desire to see more drove a few impulsive decisions. The positive side is that I bought a substantial part my astronomy collection used at very reasonable prices. There was also some investment of time to repair and adjust items that the previous owner altered or damaged. I was doing visual observations and enjoyed the views. But, I wanted to see more . . . Having a Yerkes-class refractor in the backyard was not an option.

 

Then, I read about CMOS cameras, various types of mounts, aperture, F/2.3 with a C9.25 SCT, stacking, SharpCap and other software, and a bunch of technical considerations to view dim objects in near real time. Was this plausible from my location? Absolutely!

 

For me EAA opened a viewing portal I never imagined could exist. The hobby took a dramatic positive turn.  My EAA price point included the essentials to get the first image on the screen and then some refinements. Unfortunately, it also includes stuff I don't use much, but some items will be sold through the classifieds.  I'm still enthralled and amazed during each viewing session.   


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#18 Howie1

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Posted 21 May 2018 - 07:59 AM

drneil ...  always feel a bit sorry for people asking for directions in getting into EAA. It is a bit of a minefield.

 

But, I see you are obviously very handy building such nice kit, and must understand the FOV with your nice collection of EP's. So read and re-read some tips which I'll offer and hopefully they'll make sense and help. Being familliar with EP sizes and the FOV they yield is crucial! So here goes.

 

* A camera with a 5mm sized sensor diagonal will get a very similar degree FOV as an EP of 5mm size on any OTA. And so on ... IE a 23mm sensor will yield very similar FOV to an EP of 23mm. It's not to the 1st decimal place .... but is a very good match in FOV. And especially helpful in thinking about what are suggested as great cameras (and are) but which may need you to think about selling your scopes in order to actually use them!

 

So be cautious (for instance) of jumping into building an EQ platform for your 300/1500mm DOB and sticking a R2 or IMX224 sensored cam on it. It'll be like sticking a highly magnifying 5mm EP on it and doing everything with that ... finding the object with a non GoTo mount is tricky with 5mm equivalent very narrow FOV. And because of the narrow FOV you'll be very limited to what objects you can see. This is why people posted suggesting getting a reducer of at least 0.5x (R2 comes with one) and using that with these small sensored cameras. The 0.5x reducer will make it behave like a 10mm EP. So you have to ask yourself three important questions .... will you handle finding objects with a camera+reducer equivalent to a 10mm EP?; and will you get enough objects in that equivalent 10mm FOV? The third question is, as reducers require a lot of focuser intravel, will the camera+reducer actually come to focus with your dobs? ... If not then you'll have to shorten the struts to achieve focus. Your DIY skills will enable to do the shortening ... but will that affect the optics badly?

 

If you do decide to use the Dob and build an Eq platform, then a big sensored cam around 23mm would be much better (behaving similarly wrt FOV as a 23mm EP). You'll fit many more objects in, and also be able to find/frame far more easily. Again, imagine doing a full observing session with a 23mm EP in the scope. If you could do that then a 23,mm sensored camera will work. But ... again it may not reach focus and you may have to shorten the struts. 

 

But ..... DSLR's and the IMX224 based cams will need a PC in-field to work and mastering SharpCap or Astrotoaster.

 

* So, you said you don't want computer in the field ... if that is absolutely a number one thing for you ... the R2 or old second hand Mallincams with CRT monitors may be the only ones around to do that. The sensors on those analogue CRT viewable cams are all about 6mm to 8mm. And it is why other posters suggested maybe if your heart is set on small sensored cams and CRT viewing (or any small sensored cam like the 224 which need pc to work), to sell one or both of those dobs to get cash to buy something like bdyer suggests - an ED80 EDT as well as a GoTo EQ or (cheaper) AltAz mount. Much less focal length than your Dobs so can handle far better the higher magnification from the small sensor sizes.

 

For the record I used in my beginning EAA a Mallincam VSS+ (5mm sensor) with Sony CRT and later an ASI224 (5mm sensor) + laptop with a ST80 (anachro frac) on a 6SE mount - all second hand - so I know it's possible. Sold it all except the VSS+.

 

* Confused? ... just read again and let the sensor size tip help you in your deliberations, along with the tip that you may need to shorten the struts of your dobs to bring some cams (the larger sensors ones and/or reduced smaller sensored cams).

 

As you do understand the FOV with different sized EP's it might help you figure out the way to go. And the $ and effort to go that way.

 

Cheers




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