Martin, So glad I watched your video this morning! I recently installed a WR35 on my Esprit 120ED and today I was going to take the old EAF that it used to use and install on my C925 (I already had the kit ready to go I just needed the ZWO EAF). I would have never guessed the focuser knob is that hard to get off. I would have assumed I was doing it wrong or would have been looking for a grub screw for an hour! Thanks for sharing your journey with us!
I swear it was easier on my Edge 8… I also saw that for use with the 0.7x reducer, the EAF bracket has a little bit too much footprint. I think you need to cut of a small part (by dremel or so) in order to make room for the slightly bigger circumference of the reducer bolt.
Can't wait! It is my turn tonight as volunteer tour guide at the Cosmos Observatory. It is forecast to stay clear from midnight. I have brought the rig with me... Fingers crossed I get to test it tonight.
I will have a temporary C11 to play with at the observatory where I am volunteering. Around the EOY this will be replaced by the actual observatory purchase; a C14. For now I don’t see myself owning one.
Nice Upgrade !! Congratulations. Huge difference between the 8 and 9.25 beyond just the obvious aperture and focal length. The 8 is an oversized 6. It has a smaller central baffle/secondary. The 9.25 has the larger baffle/secondary of the 11 and 14. Bigger image circle if you rid yourself of the SCT threaded adapter. Get a different 3.25 adapter plate and OAG adapter so you can have something larger than the 39.5mm internal diameter that the SCT-OAG interface gives you . With an APS-C sensor it's probably worth investigating so you can get the prism out a bit further away from the optical center. That allows you to rotate the imaging camera independently of the guide camera without interference. Wait.. you said it's a ZWO 294MC Pro? That's a 4/3" sensor with a 23mm diag. Not APS-C. Still the same applies. I'm sure you'll like the 9.25. Much better than the 8.
Hey, thanks for your comment. Did I get my sensor size wrong? 🤦♂️I have the Celestron OAG, so I think rotating the camera for framing is not a concern when I rotate the entire camera+prism - a feature of the Celestron OAG.
@@KopLampYou mentioned it was APS-C in another reply thread. I have to correct my previous comment as I keep forgetting that both scopes are HD Edge. The image circle of the 8HD and 9.25HD are both listed at radius of 21 mm (42 mm diameter). This will support APS-C sensors with diagonals of up to 28.4mm (Nikon) but not full frame sensors (43.2 mm diagonal). When using an OAG you have to also consider prism illumination. The prism sits outside the FOV of the sensor but must still be inside the image circle. To figure out if it will fit you need to calculate using the radius (distance from center) rather than diameters. The Nikon APS-C is 15.6mm x23.6mm. The distance from center on the long edge is 7.8mm +12mm for the prism, = 19.8mm, just inside the 21 mm circle radius. However, there is light intensity drop off as you near the image circle edge, worse if you shift the prism along the edge. Also, no adjustment for FOV angle has been made. Finding guide stars may be problematic depending on the sensor size, FOV and sensitivity of the guide camera. Guiding off the short edge has only partial illumination of the prism. The 294mc is a 4/3 sensor 19.1 mm x 13.0 mm. Distance from center is 6.5mm + 12mm = 18.5 mm a better fit. This explanation is necessary to understand what the huge advantage of the 9.25 is over the 8. The Celestron Focal Reducers are completely different! Because the 9.25 has the larger baffle size it uses the same FR design as the 1100 and 1400. You remove the SCT rear plate and thread the reducer onto the 3.25" threads. You retain the 21 mm radius/42mm diameter image circle. The 8HD small baffle cannot support this. The FR threads onto the SCT threads and the image circle shrinks to 26.7 mm. That just covers a Canon APS-C but not a Nikon APS-C, although you'll get severe vignetting. The radius of 13.4 makes using an OAG impossible. So, you can now add the Celestron Focal reducer which gives you an additional full stop reduction in exposure time and drops the focal length down to 1645 mm. To me, that's a huge step for your astrophotography. Now you need some clear skies and not to much aurora activity 😁😁 The 294mc is a great choice for the 9.25HD. I think you might find that rotating the imaging camera independent of the prism is an advantage as guide stars can be hard to find for some objects however there isn't that much room for the prism so it's a bit of a wish anyway. A lot depends on the light pollution, seeing and guide camera. Stellarium can do a nice job displaying FOV of both main and guider cameras which helps planning. I'm in terrible B8 skies and very near the pacific ocean so usually seeing is limited well below my aperture. Cheers from California.
@@hbmike47 I Don't worry about auroral activity. Those are rarely seen from my latitude (53N). I haven't had issues yet finding guide stars. The 174MM mini is a good fit.
@@KopLamp indeed it is. You are well optimized. The 9.25 really is the sweet spot for Celestron Compared to the 8, night and day better from those that I hear from. I think because the larger baffle gets SO much more light through and that F2.5 primary is sharper than the F2. Together it's really a different world. I have a 1100 XLT and have a slew of Meade SCTs. I have to pack and travel a few hours to put the bigger ones to good use.
Ben erg benieuwd inderdaad. Moet wel een keer eerst de collimatie goed krijgen. Heb nog geen sterren kunnen zien met de telescoop. Het is bij die first light gebleven.
I use the TC40 only when traveling. With enough weight in the bag, I expect it to fair well. But it is too early for me to come to conclusions on that regard. First need some experience under the stars...
Hi Martin, I enjoyed your video. I have the ZWO AM5 with a 90mm refractor and am looking for more focal length so considering the 8inch or 9.25inch edge HD but have been told that ZWO do not recommend going above a focal length of 1000mm on the AM5. Do you have any concerns using the edge HD on the ZWO AM5?
That is a very good question. I have not experienced issues with my AM5 and the longer focal lengths. I don’t fully understand the reasoning of the ZWO advice to be honest.
I got a second hand EdgeHD 9.25 recently too although haven't had a chance to image with it yet. What tripod are you using with it and the AM5? I think I need to get something more sturdy, it seems close to falling over with my carbon fibre tripod at the moment when it is at certain positions. Thank you
I have the PE200 which allows me to mount the EdgeHD 9.25 and the AM5 on my iOptron literoc tripod. I am on 52N and I find I am not in tipping danger even on the carbon tripod.
One question has occured to me. Is your OTA back heavy? With my C925 on the AM5 mount I can not get it far enough forward to balance and find when I unlock the pitch angle tensioner the OTA wants to flop back. This requires me to run a small counterweight just to be able to polar align. I am assuming the dimensions and weights of the EDGEHD 925 and C925 are pretty close to the same.
Are you referring to backdriving? I haven't tested that yet. I will have to first experience a night under the stars with it. I have an Astrozap powered dewshield, which will probably also offset the weight a bit.
@@KopLamp no, nothing to do with the internals. When I go to Polar align and unlock the pitch angle tensioners (big wing nuts on the side) the weight of the OTA will cause it to fall backward and will not rest against the pitch angle fine-tuning screw. it will essentially be pointed straight up in the air unless I add a small counterweight. I have not had condensation problems and have not required a dew shield.. I'm sure that would make the difference. I didn't think of that when I was watching you adjust focus on the moon. Thanks!
The backfocus is the same so nothing should change if the SCT thread adapter is already threaded onto the baffle lock nut on the 9.25. The instruction changes because the 9.25 and larger measure from the rear of the scope at the baffle lock nut not the end of the SCT threads like the 8". The 8" baffle is different and the threaded adapter part is already there. You'll get messed up using calipers unless you remember to account for the threads going into other parts like the SCT to OAG adapter threading onto the SCT threads. The APS-C sensor is the largest the image circle of the HD supports. It's a tight fit to get the OAG prism adjusted so that it doesn't block the imaging camera and still gets illuminated by the scope.
@hbmike47 You corrected me to say I don’t have an APS-C sensor size with my 294MC-pro. The back focus seems to be correct, judging from the scarce time I had under the stars…
@@KopLamp yes, it's micro 4/3 modded by ZWO to go a bit further to the sensor edge than the standard Sony sensor. 19.1 mm x 13.0 mm , 23.2 mm diagonal. Sorry for any confusion. It's as big as you can go while using an OAG with an HD Edge version scope. All that I meant to add is that WITHOUT the OAG you can use an APS-C sensor on the HD. APS-C sensor with OAG gets problematic. Just too tight IMO. The non-HD scopes have some additional options.
ZWO EAF Bracket for Celestron C8/C9.25/C11/C14 For Celestron EdgeHD 9.25" and the Celestron .7x Reducer Lens for EdgeHD 925 # 94245 you will have to file down the rounded end of the Bracket that mounts to the Telescope Focus. If not you cannot screw on the Reducer and when you have the Reducer installed you cannot mount the bracket to the Telescope Focus, 1/16 of an inch to big.
Ik heb de instructies zoals in de handleiding van de OAG gevolgd. s3.amazonaws.com/celestron-site-support-files/support_files/93648-Off-Axis-Guider_Manual.pdf Zal het nog eens nameten. Misschien moet ik deze video maar eens overdoen. Dank voor de feedback.
@RudolfNicolai Heb er nog geen tijd voor gehad, maar het whitepaper van de Edge laat zien dat je moet beginnen te meten direct aan de telescoop. Dat is anders dan bij de 8”. Daar begint de meting bij het schroefdraad waar de visual back op zit. Bij de 9.25” en groter is de backfocus inclusief de dikte van de locking bolt (die hele grote bout die achter op de telescoop zit).
@@KopLamp ook alles even na gemeten. Edge8hd. SCT=25,3 OAG=29 M-adapter =12,5 Medium T-ring =11,55. Filterlade =21. ZWO 16,5 spacer. Dan de backfocus van de 533mc. 11 plus 6.5. Kom ik op 133,3.
Martin, So glad I watched your video this morning! I recently installed a WR35 on my Esprit 120ED and today I was going to take the old EAF that it used to use and install on my C925 (I already had the kit ready to go I just needed the ZWO EAF). I would have never guessed the focuser knob is that hard to get off. I would have assumed I was doing it wrong or would have been looking for a grub screw for an hour! Thanks for sharing your journey with us!
I swear it was easier on my Edge 8… I also saw that for use with the 0.7x reducer, the EAF bracket has a little bit too much footprint. I think you need to cut of a small part (by dremel or so) in order to make room for the slightly bigger circumference of the reducer bolt.
@@KopLamp thanks very much for the heads up!
Congratulations on the new scope I'm sure you're going to have a lot of fun with it.
Clear skies
Can't wait! It is my turn tonight as volunteer tour guide at the Cosmos Observatory. It is forecast to stay clear from midnight. I have brought the rig with me... Fingers crossed I get to test it tonight.
Congrats on the new scope. You know the 11" SCT is next just around the corner XD.
I will have a temporary C11 to play with at the observatory where I am volunteering. Around the EOY this will be replaced by the actual observatory purchase; a C14.
For now I don’t see myself owning one.
Grats on the new scope. I've been tempted to make the same upgrade myself. CS!
This was an opportunity that presented itself. I wasn't looking for an upgrade, but this was too good to be skipped.
Congrats on the upgrade! And love your intro as always.
Haha.. Thanks!
Nice setup 👍🏼. Your videos are really excellent!! CS!
Glad you like them! This beast will probably give me some problems that will serve as some food for thought for upcoming videos 😎
Nice Upgrade !! Congratulations.
Huge difference between the 8 and 9.25 beyond just the obvious aperture and focal length.
The 8 is an oversized 6. It has a smaller central baffle/secondary. The 9.25 has the larger baffle/secondary of the 11 and 14. Bigger image circle if you rid yourself of the SCT threaded adapter. Get a different 3.25 adapter plate and OAG adapter so you can have something larger than the 39.5mm internal diameter that the SCT-OAG interface gives you . With an APS-C sensor it's probably worth investigating so you can get the prism out a bit further away from the optical center. That allows you to rotate the imaging camera independently of the guide camera without interference.
Wait.. you said it's a ZWO 294MC Pro? That's a 4/3" sensor with a 23mm diag. Not APS-C. Still the same applies.
I'm sure you'll like the 9.25. Much better than the 8.
Hey, thanks for your comment. Did I get my sensor size wrong? 🤦♂️I have the Celestron OAG, so I think rotating the camera for framing is not a concern when I rotate the entire camera+prism - a feature of the Celestron OAG.
@@KopLampYou mentioned it was APS-C in another reply thread.
I have to correct my previous comment as I keep forgetting that both scopes are HD Edge.
The image circle of the 8HD and 9.25HD are both listed at radius of 21 mm (42 mm diameter). This will support APS-C sensors with diagonals of up to 28.4mm (Nikon)
but not full frame sensors (43.2 mm diagonal). When using an OAG you have to also consider prism illumination. The prism sits outside the FOV of the sensor but must still be inside the image circle. To figure out if it will fit you need to calculate using the radius (distance from center) rather than diameters. The Nikon APS-C is 15.6mm x23.6mm.
The distance from center on the long edge is 7.8mm +12mm for the prism, = 19.8mm, just inside the 21 mm circle radius. However, there is light intensity drop off as you near the image circle edge, worse if you shift the prism along the edge. Also, no adjustment for FOV angle has been made. Finding guide stars may be problematic depending on the sensor size, FOV and sensitivity of the guide camera.
Guiding off the short edge has only partial illumination of the prism. The 294mc is a 4/3 sensor 19.1 mm x 13.0 mm. Distance from center is 6.5mm + 12mm = 18.5 mm a better fit.
This explanation is necessary to understand what the huge advantage of the 9.25 is over the 8.
The Celestron Focal Reducers are completely different!
Because the 9.25 has the larger baffle size it uses the same FR design as the 1100 and 1400.
You remove the SCT rear plate and thread the reducer onto the 3.25" threads. You retain the 21 mm radius/42mm diameter image circle. The 8HD small baffle cannot support this. The FR threads onto the SCT threads and the image circle shrinks to 26.7 mm. That just covers a Canon APS-C but not a Nikon APS-C, although you'll get severe vignetting. The radius of 13.4 makes using an OAG impossible.
So, you can now add the Celestron Focal reducer which gives you an additional full stop reduction in exposure time and drops the focal length down to 1645 mm.
To me, that's a huge step for your astrophotography.
Now you need some clear skies and not to much aurora activity 😁😁
The 294mc is a great choice for the 9.25HD. I think you might find that rotating the imaging camera independent of the prism is an advantage as guide stars can be hard to find for some objects however there isn't that much room for the prism so it's a bit of a wish anyway. A lot depends on the light pollution, seeing and guide camera.
Stellarium can do a nice job displaying FOV of both main and guider cameras which helps planning.
I'm in terrible B8 skies and very near the pacific ocean so usually seeing is limited well below my aperture.
Cheers from California.
@@hbmike47 I Don't worry about auroral activity. Those are rarely seen from my latitude (53N).
I haven't had issues yet finding guide stars. The 174MM mini is a good fit.
@@KopLamp indeed it is. You are well optimized.
The 9.25 really is the sweet spot for Celestron Compared to the 8, night and day better from those that I hear from. I think because the larger baffle gets SO much more light through and that F2.5 primary is sharper than the F2. Together it's really a different world.
I have a 1100 XLT and have a slew of Meade SCTs. I have to pack and travel a few hours to put the bigger ones to good use.
mooi op tijd voor de planeetjes.
Ben erg benieuwd inderdaad. Moet wel een keer eerst de collimatie goed krijgen. Heb nog geen sterren kunnen zien met de telescoop. Het is bij die first light gebleven.
@@KopLampja en het weer moet hier in NL mee doen. Augustus word geen heldere avonden.
@@KopLamp ik geloof vanavond en vannacht klaart t op.
Klopt. Dat hoorde ik ook. Moet wel tot middernacht rondleiding geven bij de Cosmos Sterrenwacht. Dus of ik daarna nog puf heb… 😅
Hey Martin, You are not using the lightweight TC40 anymore ? No tipping over issues ?
I use the TC40 only when traveling. With enough weight in the bag, I expect it to fair well. But it is too early for me to come to conclusions on that regard. First need some experience under the stars...
Hi Martin, I enjoyed your video. I have the ZWO AM5 with a 90mm refractor and am looking for more focal length so considering the 8inch or 9.25inch edge HD but have been told that ZWO do not recommend going above a focal length of 1000mm on the AM5. Do you have any concerns using the edge HD on the ZWO AM5?
That is a very good question. I have not experienced issues with my AM5 and the longer focal lengths. I don’t fully understand the reasoning of the ZWO advice to be honest.
I got a second hand EdgeHD 9.25 recently too although haven't had a chance to image with it yet. What tripod are you using with it and the AM5? I think I need to get something more sturdy, it seems close to falling over with my carbon fibre tripod at the moment when it is at certain positions. Thank you
I have the PE200 which allows me to mount the EdgeHD 9.25 and the AM5 on my iOptron literoc tripod. I am on 52N and I find I am not in tipping danger even on the carbon tripod.
One question has occured to me. Is your OTA back heavy? With my C925 on the AM5 mount I can not get it far enough forward to balance and find when I unlock the pitch angle tensioner the OTA wants to flop back. This requires me to run a small counterweight just to be able to polar align. I am assuming the dimensions and weights of the EDGEHD 925 and C925 are pretty close to the same.
Are you referring to backdriving? I haven't tested that yet. I will have to first experience a night under the stars with it. I have an Astrozap powered dewshield, which will probably also offset the weight a bit.
@@KopLamp no, nothing to do with the internals. When I go to Polar align and unlock the pitch angle tensioners (big wing nuts on the side) the weight of the OTA will cause it to fall backward and will not rest against the pitch angle fine-tuning screw. it will essentially be pointed straight up in the air unless I add a small counterweight. I have not had condensation problems and have not required a dew shield.. I'm sure that would make the difference. I didn't think of that when I was watching you adjust focus on the moon. Thanks!
Does this setup give you the required 146mm backfocus?
I put some calipers in awkward angles and think I got it. Anyway, I have an ASI294MC Pro which is APS-C sized. So I think I have a little leeway.
The backfocus is the same so nothing should change if the SCT thread adapter is already threaded onto the baffle lock nut on the 9.25. The instruction changes because the 9.25 and larger measure from the rear of the scope at the baffle lock nut not the end of the SCT threads like the 8". The 8" baffle is different and the threaded adapter part is already there.
You'll get messed up using calipers unless you remember to account for the threads going into other parts like the SCT to OAG adapter threading onto the SCT threads.
The APS-C sensor is the largest the image circle of the HD supports.
It's a tight fit to get the OAG prism adjusted so that it doesn't block the imaging camera and still gets illuminated by the scope.
@hbmike47 You corrected me to say I don’t have an APS-C sensor size with my 294MC-pro.
The back focus seems to be correct, judging from the scarce time I had under the stars…
@@KopLamp yes, it's micro 4/3 modded by ZWO to go a bit further to the sensor edge than the standard Sony sensor. 19.1 mm x 13.0 mm , 23.2 mm diagonal. Sorry for any confusion.
It's as big as you can go while using an OAG with an HD Edge version scope. All that I meant to add is that WITHOUT the OAG you can use an APS-C sensor on the HD. APS-C sensor with OAG gets problematic. Just too tight IMO. The non-HD scopes have some additional options.
ZWO EAF Bracket for Celestron C8/C9.25/C11/C14
For Celestron EdgeHD 9.25" and the Celestron .7x Reducer Lens for EdgeHD 925 # 94245 you will have to file down the rounded end of the Bracket that mounts to the Telescope Focus. If not you cannot screw on the Reducer and when you have the Reducer installed you cannot mount the bracket to the Telescope Focus, 1/16 of an inch to big.
I’ve heard about that from someone before indeed… I guess I’ll need to impersonate Adam Savage at some point and do a video on that task 😇😎
Celestron - Blue Pill - EdgeHD
That explains the deja-vu’s 😅
@@KopLampHave fun with your new toy ☺
Maar nu klopt je backfocus toch niet!!Volgens mij mis je nog 11 mm??
Ik heb de instructies zoals in de handleiding van de OAG gevolgd. s3.amazonaws.com/celestron-site-support-files/support_files/93648-Off-Axis-Guider_Manual.pdf
Zal het nog eens nameten. Misschien moet ik deze video maar eens overdoen. Dank voor de feedback.
@@KopLamp Ik was er ook mee aan het stoeien. 😉. Zelfde Edge. OAG, geen reducer. Wel de ZWO filterlade en een 533MC.
@RudolfNicolai Heb er nog geen tijd voor gehad, maar het whitepaper van de Edge laat zien dat je moet beginnen te meten direct aan de telescoop. Dat is anders dan bij de 8”. Daar begint de meting bij het schroefdraad waar de visual back op zit. Bij de 9.25” en groter is de backfocus inclusief de dikte van de locking bolt (die hele grote bout die achter op de telescoop zit).
Mijn eerste reactie kan ook helemaal fout zijn hoor. Excuus alvast. ps. Ik kijk graag naar je filmpjes.
@@KopLamp ook alles even na gemeten. Edge8hd. SCT=25,3 OAG=29 M-adapter =12,5 Medium T-ring =11,55. Filterlade =21. ZWO 16,5 spacer. Dan de backfocus van de 533mc. 11 plus 6.5. Kom ik op 133,3.