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Camera recommendations for an Edge 11

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#1 Lead_Weight

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Posted 14 February 2019 - 08:16 PM

I've picked up a used one, and am having it cleaned. Only 3 years old. I'm going to image with it reduced .7x using Celestron's reducer. I'm on a CGX mount, and doubt I can image at the native focal length without issues.

 

My intent is to image small galaxies, planetary nebula, and some planets. 

 

Current cameras, ZWO ASI1600MM-C, ASI224MC, ASI290MM Mini. with 31mm Astrodon filters.

 

Should I stick with the existing camera, or get something with larger pixels? I think the 224 will be fine for planets. But possibly need something for DSOs.

 

OAG, guiding needs possibly. Looking to get a focuser as well.

 

I have no existing accessories for this thing either. Any considerations for cooling, etc?

 

No real budget at this point. Just looking to see what I should consider.

 

Thanks.



#2 GregsCNAccount

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Posted 15 February 2019 - 12:33 AM

All of your cameras have pixels 3.75 um or smaller.  That's really way too small for the HD1100 at f/7 for DSO imaging.  I have the same scope at f/7 and use a QHY10 with 6.05 um pixels which yields 0.62 arcseconds per pixel.  The central spot size is around 12 um with this set up, so the QHY10 has about optimal pixel scale for a fully sampled image if seeing conditions were ideal, which they never are, of course.  So an even larger pixel scale would be reasonable.  An alternative would be to bin 2x2 with your current cameras which would give a 2 times larger image scale and 4 time the full well capacity

 

One of the advantages of larger pixels is the larger full well capacity.  This increases the potential dynamic range that can be captured in a single subframe and minimizes the saturation of bright stars which helps preserve star color in processing.

 

I highly recommend off-axis guiding at all focal lengths but especially at the longer focal lengths like 2000 mm. 

 

I have not found the need for an additional focuser.  I find that with a Bahtinov mask I can get very accurate focusing with the stock knob.  Remember to always finish focusing by turning the knob counterclockwise so you are pushing the primary mirror up hill.  I think more important is to combat the focus change with temperature that is magnified by the SCT design.  This could be done with an external focuser, but I think attacking the fundamental cause makes more sense.  I have replaced the aluminum optical tube with a carbon fiber replacement from Public Missiles.  I have very little focus change now over a 20 degree F temperature change so I can go several hours without worrying about focus.

 

You mention cooling and that is more important with a carbon fiber tube, which has less thermal conductivity than the aluminum tube and will thus cool slower.  I use the Starizona Cool Edge SCT Cooler to get the optics to ambient temperature at the start of the night.  This draws large amounts of air through the secondary opening and cools both the primary and secondary pretty quickly.  You may want to take a look at this review of both the Cool Edge and the Tempest fans that replace the rear vents:   

 

http://compubuild.co...0HD/thermal.htm  

 

I don't have the Tempest fans and have yet to do any planetary work, but I do not see any evidence of tube currents with the carbon fiber tube after initial cooling.  This may be due to the lower thermal conductivity of the carbon fiber over aluminum which keeps the side wall cooling rate closer to that of the primary mirror.  That's purely my speculation, though.


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#3 Dimperev

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Posted 15 February 2019 - 01:49 AM

    I have the same hardware, but my configuration is different.
    I use the Celestron 0.7x gearbox and the CCD47 (https://www.teleskop...pe-bis-F-8.html) 0.67x cgearbox in series with it. It is necessary to choose a little arrangement of elements for a flat field.
As a result, I have a focal ratio F5.2. The display scale with the ZWO ASI1600MM-C camera is 0.52 arc-seconds per pixel. This is a little less than my expectations, but it works well. This scale is convenient for subsequent alignment and integration of images.
     The second change that is important is the thermal insulation of the Edge 11 case and its rear panel (reflex). There have been many discussions. It works very well.

 

I wish you good luck and a clear sky!


Edited by Dimperev, 15 February 2019 - 01:56 AM.


#4 einarin

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Posted 15 February 2019 - 01:59 AM

So you have 2 reducers ?

I thought that it would work only for small chip size cameras.

How are you stars at the edge of ASI1600 ?



#5 freestar8n

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Posted 15 February 2019 - 02:54 AM

Many of my recent images are with ASI1600 at f/7 - and some are even at f/10:

 

https://www.astrobin...ers/Freestar8n/

 

If you guide well with OAG and you have good seeing, you may get stars with fwhm below 2" and for that I would want pixels the size of the ASI1600.  And even if your stars are 3-4" fwhm, the low read noise means you can bin or low pass filter to smooth the result - and have minimal negative impact from the small pixels.

 

I have also done some guidescope guided imaging with that configuration - but I haven't posted examples.  With short enough exposures (1-2 minutes) you may do ok with guidescope.  But I strongly recommend OAG for best results.

 

But I think you can get good use out of your ASI1600 and I would spend money on a good OAG and guide camera - preferably a 1.25" sensitive cmos camera.

 

Oh - and I focus with a stepper motor on the primary focusing knob directly.  As long as you remove backlash it works very well with autofocus - and greatly simplifies the imaging train.  I autofocus about every 40 minutes, and it handles temperature drift very well.

 

Frank


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#6 Dimperev

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Posted 15 February 2019 - 03:29 AM

If I am focused on the center of the frame, then the size of the star in the corner of the frame is about + 15-25%.
If I focus on 1/4 of a frame from the center, then the size of the star in the center of the frame and on the long side of the frame is + 5-7%, and in the corner of the frame is about + 10-15%. It depends a little on the filter used. For some reason, "Ha" is a little worse.
But I have not yet picked up the correct location of reducers.
This is the third option. Soon I will go to my observatory, which is located 5,000 km from my house. I hope to get good results after small changes. I hope for the weather!


Edited by Dimperev, 15 February 2019 - 03:33 AM.


#7 einarin

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Posted 15 February 2019 - 03:36 AM

Is the F5.2 calculated or platesolved(measured) value ?



#8 Dimperev

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Posted 15 February 2019 - 05:03 AM

5.2 is the measured value.
I had to reduce the distance to the camera to align the image plane.



#9 Lead_Weight

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Posted 15 February 2019 - 01:19 PM

I'm definitely going to look into the cooler. And possibly the camera with the larger sensor. OSC sounds like it might be nice to use. Since I have the 1600, might as well try it. But longer term, think I will be happier with a better sensor for this scope. 

 

Don't think I want to try dual reducers, I do want a longer focal length. Just not sure what I can manage with the mount I have. I also like the preciseness when focusing with my Moonlite's so not quite sure what direction I'll go with focusing on this thing. Wondering if that inexpensive focuser from Celestron is any good. Can't imagine its great with the inherent design issues in these things with the mirror flop. Assuming you could account for backlash and flop it might work.



#10 pyrasanth

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Posted 15 February 2019 - 01:30 PM

This is a case for the Edge 11 where a 16803 would be pretty much an ideal camera with a pixel size of 9 um. However that is quite a sizeable investment & the next best option would be to choose a sensor of around 6 um which makes the 16200 sensor ideal especially when binned 2x2 giving you a pixel size of 12 um- seems big- not at all for that image scale.

 

I used to fear binning thinking that detail would be lost but unless your on the moon, on most days, the detail is never there and your just increasing resolution and capturing nothing. Some of my best images have been at 9 um with the edge 11 ( Atik 460 at 2x2 bin). I can't wait to roll out the new 16200 camera. I've just finished shooting the dark frame set but I'm waiting for Bisque to ship me a new telescope control board as the one I have has failed. The camera is ready to go for first light and on the C14 I will have no fear of 2x2 bin giving me an image scale of 0.90 arc secs per pixel with the reducer. This pretty much mostly is the limits of my suburban seeing so I fear no data loss.

 

Have fun & clear skies to you all.


Edited by pyrasanth, 15 February 2019 - 01:30 PM.

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#11 Lead_Weight

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Posted 15 February 2019 - 04:01 PM

Yeah, I'm kinda curious how seeing is going to have an effect on a large scope. I'm outside of Houston, and it's fairly humid, so seeing is often limited due to humidity in the air or rapid changes in temp.



#12 astroian

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Posted 17 February 2019 - 05:23 AM

A good match for the C11 is the ATIK 414 camera. You can see some examples on my AstroBin page, e.g. https://astrob.in/319323/0/

The QSI6120 binned at 2x2 also appears to be a good match with the .7 reduced C11. See https://astrob.in/383345/0/

Cheers,
Ian

#13 Lead_Weight

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Posted Yesterday, 12:15 AM

I had first light with my Edge 11 setup.

 

I ended up with the ZWO ASI071MC Pro camera. An 2" Astronomic UV/IR L2 Cut filter. The Moonlite CHL low profile focuser, a Celestron .7 reducer, and the ZWO OAG with 290mm Mini.

 

I was able to bring everything to focus during the daylight. Then once it got dark, had to readjust everything as stars were much further away than whatever I practiced on.

 

At first, it was a pain adjusting the OAG, I had oblong stars, and rotating/moving it around finally fixed it. I don't really like the orientation, but can't seem to get it to face another direction. Right now, it's on the bottom side of the long flat edge of the 071.

 

Finding guide stars was really painful. I visited M108, M101, M106, M51, and M3, and couldn't get a single guide star. I upped the gain on the 290mm to 300 and could just barely pick out two stars, but the guiding software wouldn't lock onto either. Also, there was a huge bright spot in the middle of the OAG camera view. I don't know if this is just heavy vignetting from the OAG tiny pass through hole or what. Getting really frustrated, I ended up putting a LPS filter on the guide camera, and that huge bright spot toned way down. I'm hoping this fixes the issues, but clouds rolled in before I could test it out.  

 

To make sure guiding worked at all, I went to an open cluster and easily found stars for the guide cam. I was around .2 to .3 RMS on guiding. But I'm really bummed I couldn't pick up any guide stars on a single galaxy. The whole reason I got this thing was to image small galaxies.

 

Before giving up for the night, I aimed at the moon and snagged a few shots.

 

edge.jpg

 

get.jpg?insecure



#14 jhayes_tucson

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Posted Yesterday, 12:49 AM

I've picked up a used one, and am having it cleaned. Only 3 years old. I'm going to image with it reduced .7x using Celestron's reducer. I'm on a CGX mount, and doubt I can image at the native focal length without issues.

 

My intent is to image small galaxies, planetary nebula, and some planets. 

 

Current cameras, ZWO ASI1600MM-C, ASI224MC, ASI290MM Mini. with 31mm Astrodon filters.

 

Should I stick with the existing camera, or get something with larger pixels? I think the 224 will be fine for planets. But possibly need something for DSOs.

 

OAG, guiding needs possibly. Looking to get a focuser as well.

 

I have no existing accessories for this thing either. Any considerations for cooling, etc?

 

No real budget at this point. Just looking to see what I should consider.

 

Thanks.

 

1)  There will be virtually zero difference in difficulty imaging at either F/10 or with the reducer at F/7.  The only reason to use a reducer is to get a larger field of view.

 

2)  Adding the reducer will give you a larger field with a small sensor; however, it greatly amplifies your chances of encountering image quality problems.  If you have a good quality reducer, you are lucky.  I hear from folks all the time having trouble with reducers.  My recommendation is always to skip the reducer, keep it simple, and go with a larger sensor.  That telescope will easily cover a 42 mm image circle and a lot of folks have successfully gone out to a 52 mm circle on a C11 Edge without serious issues.  If you are afraid of imaging at F/10, you'll quickly find that going to F/7 doesn't help--particularly if you want to go after small galaxies.  For those objects you need the image scale and optical quality available in the native focal plane.  In this case, simple is better.

 

3)  For long exposure imaging, the optimum pixel size for that scope at F/10 is around 5-6 microns.  You can go smaller than 5 microns, but I wouldn't go much bigger than 7 microns.

 

4)  That scope has a large nicely corrected flat field, so if it were me, I'd be thinking about using the largest sensor that I could find that has pretty good sensitivity.  For long exposure DSO imaging, a camera with a KAI-16200 chip would be a nice match--even though the chip size is a little smaller than I'd like.  (I like really big chips!)  For planets, you want a CMOS camera so that you can read it out much faster.

 

5)  You can focus with the existing system in the Celestron; but, that's not what I'd do.  I'd get an Optec SMFS for moving the secondary mirror to control focus.  That way, you can lock down the primary mirror to prevent mirror shift and have a zero backlash focusing system.  That allows real time, precision focusing with an ONAG guider.

 

Good luck with it...

 

John


Edited by jhayes_tucson, Yesterday, 12:51 AM.


#15 freestar8n

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Posted Yesterday, 04:11 AM

I had first light with my Edge 11 setup.

 

I ended up with the ZWO ASI071MC Pro camera. An 2" Astronomic UV/IR L2 Cut filter. The Moonlite CHL low profile focuser, a Celestron .7 reducer, and the ZWO OAG with 290mm Mini.

 

I was able to bring everything to focus during the daylight. Then once it got dark, had to readjust everything as stars were much further away than whatever I practiced on.

 

At first, it was a pain adjusting the OAG, I had oblong stars, and rotating/moving it around finally fixed it. I don't really like the orientation, but can't seem to get it to face another direction. Right now, it's on the bottom side of the long flat edge of the 071.

 

Finding guide stars was really painful. I visited M108, M101, M106, M51, and M3, and couldn't get a single guide star. I upped the gain on the 290mm to 300 and could just barely pick out two stars, but the guiding software wouldn't lock onto either. Also, there was a huge bright spot in the middle of the OAG camera view. I don't know if this is just heavy vignetting from the OAG tiny pass through hole or what. Getting really frustrated, I ended up putting a LPS filter on the guide camera, and that huge bright spot toned way down. I'm hoping this fixes the issues, but clouds rolled in before I could test it out.  

 

To make sure guiding worked at all, I went to an open cluster and easily found stars for the guide cam. I was around .2 to .3 RMS on guiding. But I'm really bummed I couldn't pick up any guide stars on a single galaxy. The whole reason I got this thing was to image small galaxies.

 

Before giving up for the night, I aimed at the moon and snagged a few shots.

 

 

Hi-

 

Your setup looks ok but I'm afraid the main thing limiting it is the OAG and the size of its prism - plus the oag viewport.  Nonetheless there are ways to improve things without spending money.

 

First - instead of just hunting for guidestars you should use a planetarium program and a FOVI (field of view indicator) - along with an angle readout on the OAG.  Simply hunting for guidestars will be frustrating - but if you know which ones are available and where they are - it becomes a matter of dialing them in - and there they are.

 

I currently use a Pyxis rotator with EdgeHD11 and I never 'hunt for' or 'find' guidestars - I just center the target - set the angle - and there they are.  You can do the same with a dial indicator and it just takes some calibration and figuring out - but it means a more systematic approach.

 

Here is a page that describes how I was doing things with a C11 ten years ago when I was doing things manually with a FOVI and degree scale:

 

https://www.astrogee...bjectNight.html

 

You can see the simple dial indicator on the OAG - and an example FOVI in TheSky that let me select a guidestar and dial in its angle.  This is the way high end users have been doing things for decades - and the only difference is automation with things like rotators.

 

All of the above can be done with no expense - but some overhead in getting things set up and calibrated.

 

The other thing that can help if you are in a position to 'hunt' for the guidestar is to make sure your gain is high and your camera is operating in interactive video mode - so you can see stars appear as you are moving around.  If your focus is good and your guidestar is nearby - you shouldn't need long exposures to see it.

 

One big improvement in all this that has happened in recent years is the ease of doing plate solving to make sure you are exactly centered on where the FOVI is laid out.  That helps make sure that when you set the OAG angle - the star will be there.

 

If you did want to spend money - the main thing I would change is the OAG itself.  The main source of frustration with OAG is a system with a small prism and a narrow view of it.  This is limiting your light from the guidestar - and causing vignetting.  If you had an OAG with a 12mm prism and a full view of it from a sensor nearby, you would have brighter stars and a wider field on your sensor.

 

And if you had a larger prism, it would let you switch to f/7 and get an additional win in brightness and field of view on the guide sensor.  But you would need to change the OAG for that to happen.

 

It's good that you have enough backfocus for the focuser because that should make focusing easier.  I recommend using automatic focus if you want to image small galaxies.

 

So - there are ways to improve your system without spending money - with a combination of simple degree scales and different technique.  But if you were able to spend more I recommend a different OAG with big prism and wide view of it.

 

Frank


Edited by freestar8n, Yesterday, 04:14 AM.


#16 Lead_Weight

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Posted Yesterday, 09:27 AM

Thanks for the info Frank. I can manually rotate the Moonlite around to find a guide star. That was the only thing I didn't do. I was hoping not to have to do that because I usually like to frame my images for the best output, not necessarily to find a guide star. Alternatively, I could get the rotator motor for the Moonlite, and achieve this automatically.

 

The only OAG I seem to be able to find with a 12mm prism is the Celestron OAG. But it looks too thick, and I don't think I'll be able to reach focus. Right now, I'm pretty much at the limit of my scopes ability with the setup I have. The primary mirror focuser is racked all the way out. I might be able to find a different spacer between the camera and OAG to offset the difference, but I'm using one that came with the camera currently, and it's the smallest one in the box. I really like the idea of an OAG with a helical focuser. Kinda wish I had shopped around, but didn't see people with too many issues using the ZWO OAG. I'm able to achieve focus by moving the camera, but it's not ideal, and can't really fine tune it easily.



#17 Lead_Weight

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Posted Yesterday, 09:42 AM

1)  There will be virtually zero difference in difficulty imaging at either F/10 or with the reducer at F/7.  The only reason to use a reducer is to get a larger field of view.

 

2)  Adding the reducer will give you a larger field with a small sensor; however, it greatly amplifies your chances of encountering image quality problems.  If you have a good quality reducer, you are lucky.  I hear from folks all the time having trouble with reducers.  My recommendation is always to skip the reducer, keep it simple, and go with a larger sensor.  That telescope will easily cover a 42 mm image circle and a lot of folks have successfully gone out to a 52 mm circle on a C11 Edge without serious issues.  If you are afraid of imaging at F/10, you'll quickly find that going to F/7 doesn't help--particularly if you want to go after small galaxies.  For those objects you need the image scale and optical quality available in the native focal plane.  In this case, simple is better.

 

3)  For long exposure imaging, the optimum pixel size for that scope at F/10 is around 5-6 microns.  You can go smaller than 5 microns, but I wouldn't go much bigger than 7 microns.

 

4)  That scope has a large nicely corrected flat field, so if it were me, I'd be thinking about using the largest sensor that I could find that has pretty good sensitivity.  For long exposure DSO imaging, a camera with a KAI-16200 chip would be a nice match--even though the chip size is a little smaller than I'd like.  (I like really big chips!)  For planets, you want a CMOS camera so that you can read it out much faster.

 

5)  You can focus with the existing system in the Celestron; but, that's not what I'd do.  I'd get an Optec SMFS for moving the secondary mirror to control focus.  That way, you can lock down the primary mirror to prevent mirror shift and have a zero backlash focusing system.  That allows real time, precision focusing with an ONAG guider.

 

Good luck with it...

 

John

Thanks for the info John. I explored the 16200 chip, but the total cost with filters was prohibitive to me. I intend to revisit it down the road. For now, I went with an OSC ZWO ASI071 camera. The pixel size is a little larger than my 1600, and should simplify imaging for me at least in the interim.



#18 rgsalinger

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Posted Yesterday, 09:59 AM

The 290 may be a bit small to use as a guide camera for that telescope and, if you are using the ZWO OAG, the prism is really too small and reducing your FOV. I use a ZWO174 mini on both of my longer focal length scopes and I get guide stars on all those (difficult) objects.  One trick I've used very successfully in the past has been to insert a small positive lens into the OAG to act as a focal reducer. Still, the problem may be the prism, I have bigger prisms in both my long scopes.

 

Rgrds-Ross



#19 Lead_Weight

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Posted Yesterday, 10:12 AM

The 290 may be a bit small to use as a guide camera for that telescope and, if you are using the ZWO OAG, the prism is really too small and reducing your FOV. I use a ZWO174 mini on both of my longer focal length scopes and I get guide stars on all those (difficult) objects.  One trick I've used very successfully in the past has been to insert a small positive lens into the OAG to act as a focal reducer. Still, the problem may be the prism, I have bigger prisms in both my long scopes.

 

Rgrds-Ross

What OAG’s are you using in those scopes?



#20 dhaval

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Posted Yesterday, 11:40 AM

We use a IC814 chip camera (QHY814A) with our C11 EdgeHD in a remote observatory setting. If you are not aware of the IC814 chip - it is a CCD with 3.6um pixels and about 12mmx10mm chip (small on both counts). We are imaging at native 2800mm FL - giving us an image scale of 0.2"/px. Admittedly, it is very challenging - we are oversampled and need an exceptional mount with exceptional guiding and seeing to have usable subs. I won't go into if it makes sense to use really small pixels and small FOV with this scope at 2800mm FL, but our reasoning in using this set up is to get "up, close and personal" with a lot of these tiny objects.

 

The point I am trying to make is - you really should figure out what you want to image and based on that, you can decide what will work or not for you. I strongly advice to think through this. When you start thinking it through, you will have a better feel for what works for you in your situation (think of this as a whole "system" - including (but not limited to) - seeing, mount, imaging train, etc.). 

 

Not that an image is the best example of what to expect, but here is one that I came up with using the data that we had from the C11/QHY814.

 

My friend who shares the rig with me, got an IOTD using the same data set - his version is here.

 

CS! 



#21 freestar8n

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Posted Yesterday, 04:19 PM

Thanks for the info Frank. I can manually rotate the Moonlite around to find a guide star. That was the only thing I didn't do. I was hoping not to have to do that because I usually like to frame my images for the best output, not necessarily to find a guide star. Alternatively, I could get the rotator motor for the Moonlite, and achieve this automatically.

 

The only OAG I seem to be able to find with a 12mm prism is the Celestron OAG. But it looks too thick, and I don't think I'll be able to reach focus. Right now, I'm pretty much at the limit of my scopes ability with the setup I have. The primary mirror focuser is racked all the way out. I might be able to find a different spacer between the camera and OAG to offset the difference, but I'm using one that came with the camera currently, and it's the smallest one in the box. I really like the idea of an OAG with a helical focuser. Kinda wish I had shopped around, but didn't see people with too many issues using the ZWO OAG. I'm able to achieve focus by moving the camera, but it's not ideal, and can't really fine tune it easily.

Hi-

 

I'm afraid I'm not sure what options are out there for a good OAG with 12mm prism.  My Hutech OAG5 is great - but I'm not sure if they are available.  You might inquire with Hutech.  Astrodon has some large ones but I'm not sure how adjustable they are - and they may be designed for much larger cameras.

 

If you are looking at small galaxies then rotation may not be an issue if you can just crop out the central region in the orientation you prefer.  The 0.7x reducer would give you more 'room' for that.

 

And if you are spending many nights on an object, you can go ahead and rotate both the OAG and the camera for the framing you want - and still get the guidestar you want.  It requires additional work for each object - but once you set it up for an object it should be fine.

 

And remember you need to rotate the whole thing 180 degrees on a meridian flip - if you image on both sides.

 

If you are able to dial in your guidestar I think you will find your current setup to work ok and you will have guidestars to guide on.  But I'm afraid with the smallish sensor and a narrow field - the odds of just finding a guidestar without planning will be low.

 

Frank



#22 DuncanM

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Posted Yesterday, 04:33 PM

Hi-

 

I'm afraid I'm not sure what options are out there for a good OAG with 12mm prism.  My Hutech OAG5 is great - but I'm not sure if they are available.  You might inquire with Hutech.  Astrodon has some large ones but I'm not sure how adjustable they are - and they may be designed for much larger cameras.

 

If you are looking at small galaxies then rotation may not be an issue if you can just crop out the central region in the orientation you prefer.  The 0.7x reducer would give you more 'room' for that.

 

And if you are spending many nights on an object, you can go ahead and rotate both the OAG and the camera for the framing you want - and still get the guidestar you want.  It requires additional work for each object - but once you set it up for an object it should be fine.

 

And remember you need to rotate the whole thing 180 degrees on a meridian flip - if you image on both sides.

 

If you are able to dial in your guidestar I think you will find your current setup to work ok and you will have guidestars to guide on.  But I'm afraid with the smallish sensor and a narrow field - the odds of just finding a guidestar without planning will be low.

 

Frank

I have one of these on order:

https://www.amazon.c...dp/B07M5N1H8K/ 

 

while these look interesting as well:

 

https://www.amazon.c...dp/B07FTG8J78/ 



#23 freestar8n

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Posted Yesterday, 05:22 PM

I have one of these on order:

https://www.amazon.c...dp/B07M5N1H8K/ 

 

while these look interesting as well:

 

https://www.amazon.c...dp/B07FTG8J78/ 

Hi-

 

That first one looks very good - along with the price.  It has a good view of the prism and it looks like you can get close to it.  This is really nice to see - and I look forward to a review.

 

One of the pictures in the add shows a comparison with other oag's in terms of a small hole through which you view the prism.  This design has a much wider view - and that's important.

 

I'm afraid the narrow stalk on the second one doesn't look ideal.

 

Combining the first one with a 1.25" guide sensor - ideally a big one like a 174 - would be a very good combination for OAG work.  With long enough guide exposure and wide enough field on the guide sensor you may not need to rotate the OAG.  But I always prefer to rotate the OAG so I can use the best guidestar available.  But for me it's automatic with a rotator.

 

Frank



#24 Ladyhawke

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Posted Yesterday, 05:28 PM

I image with an Edge 11" + Reducer + Atik 460. Look up my Astrobin linked below.

 

I use a ZWO OAG and love it, cheap and no issues at all. The focuser I lock the mirror and use a Moonlight Crayford and my guiding camera is a Lodestar. I also have a TempEst fan installed. Out of my 6 scopes, this is my favorite setup.


Edited by Ladyhawke, Yesterday, 05:32 PM.


#25 Lead_Weight

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Posted Yesterday, 05:57 PM

I image with an Edge 11" + Reducer + Atik 460. Look up my Astrobin linked below.

 

I use a ZWO OAG and love it, cheap and no issues at all. The focuser I lock the mirror and use a Moonlight Crayford and my guiding camera is a Lodestar. I also have a TempEst fan installed. Out of my 6 scopes, this is my favorite setup.

Do you have any issues finding guide stars? Do you use a rotator of any kind?




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