Interesting! Can you maybe explain how to use a tri-Bhatinhov mask for collimation? I understand how to use a regular Bhatinhov for focusing, but how to use the tri? I can’t find any reference sources on how to use it correctly!
It does. I have that reducer and have tried it at various back focus distances with moving mirror maks and the best I could do was a 3 F ratio reduction. I reached out the Astro Physis and since the SCT is also a moving mirror design the backfocus to reduction chart does not hold true. Do you mind sharing your back focus distance and the reduction you are able to get? Thanks. @@tomsastrophotochannel3243
1:50 I guess another reason I'm not going to buy a off the shelf mount, they charge you an insane amount for something that really can't reliably lift and accurately move most equipment people with that much money use. Sure they work for those anemic refractors but the other scope types are not accounted for.
Congrats on the new scope Tom! Would have been nice to actually see the collimation process using the tri bat mask as I've been thinking of trying one for my 9.25 Edge
Thanks Simon! You put the mask on, align with the 3 screws, take a pic of a bright star, check the collimation pattern, turn the screws until each bathinov pattern looks symmetric, finish ;). Hope this helps, Tom
Love this video! I also just purchased a 10” ACF, and hearing your review makes very glad about my decision. I’ve been using the LX200 classic and I’m really looking forward to the optical improvement! Where did you get that collimation mask? Also, how well do you find it guides at the native focal length? (if I saw correctly, you had a guide scope as opposed to OAG)
What puzzles me is the (stock) location of the carry handle on the OTA. This scope is uncomfortable to mount without an optional grab handle on top of the tube. Shattered correctors are common due to poor ergonomics on these bulky short tubes. Otherwise, the scope balances well on both EQ and manual mounts in the appropriate weight class. Thanks for the B-mask tip. Enjoy your new Meade !!
The handle is properly placed. It is in this location not for loading onto a saddle but for turning the OTA when unpowered. No SCT or Mak places a handle longitudinally in a permanent location because that would upset the normal balance. If you need a handle for placing the OTA, then consider building a simple quick connect handle if you have a top plate like Tom, or a tube grabber out of wood that cradles the OTA while you lift it onto the mount. For large OTAs consider using a side table to hold the OTA vertical and rotate the saddleplate to the side of the mount and align the saddle and the dovetail without having to lift.
@@mycarolinaskies The Takahashi Mewlon 210 has a specifically engineered dual-purpose carry handle / guide scope. There's grab handles..and carry handles. In practice, people use the Meade 10" single grab handle for lifting. If Meade felt the rear cell casting couldn't support the stress of a straight lift with the single grab handle , they surely would have indicated that with a warning label. The placement of an aftermarket QR- type carry handle on a top-plate works, but it's expensive and adds weight. When I de-forked an older C8, I removed the rear cell and added a (rack mount) carry handle on the back top center. Easy to swing the OTA up in a single motion. A vendor (CN) indicates the shear strength of Celestron / Meade handles at around 1500 lbs. My Meade 10" has to go into a tight-fitting Pacific Designs soft case. Thanks for the clarification and suggestion(s) CS :)
Nice comparison. Looks like in the R/C vs ACF comparison stars the ACF has better star roundness. Would be nice to see the two globular images scaled similarly side by side(like the uncollimated vs collimated) to give a better comparison. Also, if you had an R/C image of the galaxy. BTW, another positive of the ACF is the sealed tube keeping the mirrors cleaner!
Hi Tom, I think the result you are seeing is mostly collimation and resolution of the 10" vs 8" system. I could be wrong but my understanding is that the f/10:version of the Meade ACF only has an oversized primary and none of the other ACF features. To get all the features of the ACF system you must go to the newer f/8 version of the scope. The f/8 version has a new internal focusing system and new 3.5" baffle tube with much better baffles that improves contrast and light transmission. The primary mirror rides on 3.5" bearings instead of floating on the baffle tube with layer of grease. Internal focuser is a 10:1 crayford with a 7:1 dual speed control. Zero mirror flop and near zero image shift. The larger baffle is about 67 mm vs 50.1 of the f/10. The backfocus on both systems is in fact 105 mm. The focal length of the 10" at f/8: is 2032 mm very comparable to the RC 8. The resolution however is better with the aperture of 250mm This is the better test. Oh, the hyperbolic secondary is larger, but the better baffles and larger light path more than make up for it. You can immediately tell what is in your scope internals by looking at the corrector plate. The Aspherical non-Schmidt corrector of actual ACF (f/8) OTA should be quite apparent. A Schmidt plate corrector it is quite difficult to see the correction. The f/8 has borosilicate Pyrex mirrors made in USA and a Schott glass (German) corrector for better transmission. The larger baffle allows you to to use a larger rear port adapter than supplied by Meade. If you image full frame the solution to fully support the ff sensor is the 3.25" to 67 mm adapter of Astro-Physics and then use A-P 2.7" (67 mm) telecompressor (quad tekecompressor recommended) with and appropriate adapter to the camera in use. This is only necessary for full frame support. Of note course is that Celestron also does not fully support Full Frame. Their HD reducer is optimized for a 42mm image circle. FF is at minimum 43.8mm
The SCT Meade Petzval curvature is better at F/8 but it is not a flatfield telescope. The coma free version is better thant the standart version but what about the rest? RC is much more complicate to make and to get optimal because the distane between mirror must be exact to avoid much more optical aberrations. ( focusing from the secondary is better for any Cassegrain ) The field of view depends of the size of the secondary mirror. The quality of glass is for the spectrum size. But the Schmidt plate is not chromatic. Therefore what is most important is the thinkness .Less is better., . What puzzle me is the focus by the primary mirror which is nonsens when there is a Schmidt plate. RC are for photography with big obstruction. This design was made for this purpose because the Schwarzschild telescope much better, was not easy to instell camera at the focus. Meade and Celestron are more visual telescope in mind. Now, full sensor or not full sensor is not an issue. Size of the spot is an issue, and this detail doesn't hurt anybody. At least when the telecompressor is built for the exact the Petzval curvature annulation, the stars are much better. If you are looking for fast telescope Celestron is ready for it. Otherwise a smart solution is to built a Slevogt telescope design from a classical Meade or Celestron SCT. Change the secondary mirror installed on a Spider closer to the primary miror and relocate the Schmidt plate. The result is minimum optical surfaces nearly perfect image huge full light field with small spots. this solution uses the SCT concept without lens corrector . This solution give s F/D 3.7 when the primary is F/D 2. Only spherical mirrors...
Hallo Wolfgang Strasser, den Steeltrack hatte ich mit dem Meade zusammen gekauft, man bekommt diesen auch bei baader, der eaf von zwo wurde montiert mittels adapter aus dem 3D drucker. Ich hoffe das hilft, Grüße Tom
Hallo, leider sieht man zum Schluss nicht ob der Doppelstern auch im RC getrennt wurde. Ansonsten ein schöner Vergleich . Ich habe ein LX200 8“ ACF von 2021. Die Optik finde ich mega scharf. Leider findet man selbst auf Astrobin kaum Fotos die damit gemacht wurden. Liebe Grüße
Endurofreund1989 richtig, die Kamera war im Weg, aber die Beiden Sterne waren sauber getrennt. Der ACF ist ein guter SCT nur leider findet man so gut wie nichts darüber im Netz. War darüber auch erstaunt. Cs. tom
@@tomsastrophotochannel3243 Thought so but one never knows until asked. Someday when I go and visit my cousin there I would like to stop by and say hello.
basically yes but with slightest wind or unbalance the EQ6R is not able to give good guiding results. The mount should always be one size bigger than the scope.
I recently got a ACF 10" F8 and it is not too bad of a telescope. But I'm not impressed by theastigmatism or curvature. I have own several RC8 and an RC10 and I think the RC8 is much much better. Huge field without a need for corrector, sharp as a tack. If I could go back in time I would still own those little scopes.
Interesting! Can you maybe explain how to use a tri-Bhatinhov mask for collimation? I understand how to use a regular Bhatinhov for focusing, but how to use the tri? I can’t find any reference sources on how to use it correctly!
Mark-Bloom: hm it is quite difficult to explain it , I think I have to make a clip to show it. Sorry. Cs tom
Nice video. You mentioned using a reducer @15:09 , what particular reducer are you using. Thank you. I have the 6" version and was curious. Thank you.
Hi, I am using the ccd47 reducer. hope this helps, Tom
It does. I have that reducer and have tried it at various back focus distances with moving mirror maks and the best I could do was a 3 F ratio reduction. I reached out the Astro Physis and since the SCT is also a moving mirror design the backfocus to reduction chart does not hold true. Do you mind sharing your back focus distance and the reduction you are able to get? Thanks. @@tomsastrophotochannel3243
This is very informative; especially about collimation.
1:50 I guess another reason I'm not going to buy a off the shelf mount, they charge you an insane amount for something that really can't reliably lift and accurately move most equipment people with that much money use.
Sure they work for those anemic refractors but the other scope types are not accounted for.
Congrats on the new scope Tom! Would have been nice to actually see the collimation process using the tri bat mask as I've been thinking of trying one for my 9.25 Edge
Thanks Simon! You put the mask on, align with the 3 screws, take a pic of a bright star, check the collimation pattern, turn the screws until each bathinov pattern looks symmetric, finish ;). Hope this helps, Tom
Love this video! I also just purchased a 10” ACF, and hearing your review makes very glad about my decision. I’ve been using the LX200 classic and I’m really looking forward to the optical improvement! Where did you get that collimation mask? Also, how well do you find it guides at the native focal length? (if I saw correctly, you had a guide scope as opposed to OAG)
What puzzles me is the (stock) location of the carry handle on the OTA. This scope is uncomfortable to mount without an optional grab handle on top of the tube. Shattered correctors are common due to poor ergonomics on these bulky short tubes. Otherwise, the scope balances well on both EQ and manual mounts in the appropriate weight class. Thanks for the B-mask tip. Enjoy your new Meade !!
Sneakerset you are absolutely right, the handle is in the wrong place beside that the Meade is a nice telescope.clear skies, Tom
The handle is properly placed. It is in this location not for loading onto a saddle but for turning the OTA when unpowered. No SCT or Mak places a handle longitudinally in a permanent location because that would upset the normal balance.
If you need a handle for placing the OTA, then consider building a simple quick connect handle if you have a top plate like Tom, or a tube grabber out of wood that cradles the OTA while you lift it onto the mount. For large OTAs consider using a side table to hold the OTA vertical and rotate the saddleplate to the side of the mount and align the saddle and the dovetail without having to lift.
@@mycarolinaskies The Takahashi Mewlon 210 has a specifically engineered dual-purpose carry handle / guide scope. There's grab handles..and carry handles. In practice, people use the Meade 10" single grab handle for lifting. If Meade felt the rear cell casting couldn't support the stress of a straight lift with the single grab handle , they surely would have indicated that with a warning label. The placement of an aftermarket QR- type carry handle on a top-plate works, but it's expensive and adds weight. When I de-forked an older C8, I removed the rear cell and added a (rack mount) carry handle on the back top center. Easy to swing the OTA up in a single motion. A vendor (CN) indicates the shear strength of Celestron / Meade handles at around 1500 lbs. My Meade 10" has to go into a tight-fitting Pacific Designs soft case. Thanks for the clarification and suggestion(s) CS :)
Nice comparison. Looks like in the R/C vs ACF comparison stars the ACF has better star roundness. Would be nice to see the two globular images scaled similarly side by side(like the uncollimated vs collimated) to give a better comparison. Also, if you had an R/C image of the galaxy.
BTW, another positive of the ACF is the sealed tube keeping the mirrors cleaner!
Nice review 🙏🏼.
Hi Tom,
I think the result you are seeing is mostly collimation and resolution of the 10" vs 8" system.
I could be wrong but my understanding is that the f/10:version of the Meade ACF only has an oversized primary and none of the other ACF features.
To get all the features of the ACF system you must go to the newer f/8 version of the scope. The f/8 version has a new internal focusing system and new 3.5" baffle tube with much better baffles that improves contrast and light transmission.
The primary mirror rides on 3.5" bearings instead of floating on the baffle tube with layer of grease. Internal focuser is a 10:1 crayford with a 7:1 dual speed control. Zero mirror flop and near zero image shift. The larger baffle is about 67 mm vs 50.1 of the f/10.
The backfocus on both systems is in fact 105 mm. The focal length of the 10" at f/8: is 2032 mm very comparable to the RC 8. The resolution however is better with the aperture of 250mm
This is the better test.
Oh, the hyperbolic secondary is larger, but the better baffles and larger light path more than make up for it. You can immediately tell what is in your scope internals by looking at the corrector plate. The Aspherical non-Schmidt corrector of actual ACF (f/8) OTA should be quite apparent. A Schmidt plate corrector it is quite difficult to see the correction.
The f/8 has borosilicate Pyrex mirrors made in USA and a Schott glass (German) corrector for better transmission.
The larger baffle allows you to to use a larger rear port adapter than supplied by Meade. If you image full frame the solution to fully support the ff sensor is the 3.25" to 67 mm adapter of Astro-Physics and then use A-P 2.7" (67 mm) telecompressor (quad tekecompressor recommended) with and appropriate adapter to the camera in use.
This is only necessary for full frame support. Of note course is that Celestron also does not fully support Full Frame. Their HD reducer is optimized for a 42mm image circle. FF is at minimum 43.8mm
The SCT Meade Petzval curvature is better at F/8 but it is not a flatfield telescope. The coma free version is better thant the standart version but what about the rest? RC is much more complicate to make and to get optimal because the distane between mirror must be exact to avoid much more optical aberrations. ( focusing from the secondary is better for any Cassegrain ) The field of view depends of the size of the secondary mirror. The quality of glass is for the spectrum size. But the Schmidt plate is not chromatic. Therefore what is most important is the thinkness .Less is better., . What puzzle me is the focus by the primary mirror which is nonsens when there is a Schmidt plate. RC are for photography with big obstruction. This design was made for this purpose because the Schwarzschild telescope much better, was not easy to instell camera at the focus. Meade and Celestron are more visual telescope in mind. Now, full sensor or not full sensor is not an issue. Size of the spot is an issue, and this detail doesn't hurt anybody. At least when the telecompressor is built for the exact the Petzval curvature annulation, the stars are much better. If you are looking for fast telescope Celestron is ready for it. Otherwise a smart solution is to built a Slevogt telescope design from a classical Meade or Celestron SCT. Change the secondary mirror installed on a Spider closer to the primary miror and relocate the Schmidt plate. The result is minimum optical surfaces nearly perfect image huge full light field with small spots. this solution uses the SCT concept without lens corrector . This solution give s F/D 3.7 when the primary is F/D 2. Only spherical mirrors...
Hallo Tom, Sie sprechen deutsch? wenn ja die Frage wo bekommt man den Baader Steeltrack mit Autofocus zu kaufen?
Danke für Ihre Antwort.
VG Wolfgang
Hallo Wolfgang Strasser, den Steeltrack hatte ich mit dem Meade zusammen gekauft, man bekommt diesen auch bei baader, der eaf von zwo wurde montiert mittels adapter aus dem 3D drucker. Ich hoffe das hilft, Grüße Tom
Hallo, leider sieht man zum Schluss nicht ob der Doppelstern auch im RC getrennt wurde. Ansonsten ein schöner Vergleich . Ich habe ein LX200 8“ ACF von 2021. Die Optik finde ich mega scharf. Leider findet man selbst auf Astrobin kaum Fotos die damit gemacht wurden. Liebe Grüße
Endurofreund1989 richtig, die Kamera war im Weg, aber die Beiden Sterne waren sauber getrennt. Der ACF ist ein guter SCT nur leider findet man so gut wie nichts darüber im Netz. War darüber auch erstaunt. Cs. tom
Hi Tom are you located in the USA?
Actually I am in Germany.
@@tomsastrophotochannel3243 Thought so but one never knows until asked. Someday when I go and visit my cousin there I would like to stop by and say hello.
@@williamkacensky4796 would be great to meet you here in Germany!
@@tomsastrophotochannel3243 Thank you Tom.
The EQ6-R should handle that scope.Unless your guide scope is hugh
basically yes but with slightest wind or unbalance the EQ6R is not able to give good guiding results. The mount should always be one size bigger than the scope.
I recently got a ACF 10" F8 and it is not too bad of a telescope. But I'm not impressed by theastigmatism or curvature. I have own several RC8 and an RC10 and I think the RC8 is much much better. Huge field without a need for corrector, sharp as a tack. If I could go back in time I would still own those little scopes.
F10….wow, must take hours to image anything. Good luck.
yep, but with my 2600MM LUM is is quite easy still need more time than with an f5 system ;)