iOptron RC8

[RolandKol]

Hi guys,

I planning a christmass gift for myself willing to upgrade my 130PDS to a slightly larger scope and slightly Longer Focal Lengh as sometimes I am really happy to image planets also. The aim, - to shoot down the Saturn .

The main purpose would be DSO (nebulas mainly, - if street light will allow, larger galaxies also).

I will hook up ASI1600MM + EFW + AOG (guide scope also available if focuser will start causing problems).

Questions:

1) The Main, -  "Should I stay, or Should I go????" Please talk me off... Maybe, I should just stay with my 130PDS and Samyang 135... But I have no challenges with them anymore and it can become a bit borring.

2) I use oldie NEQ6 Mount....  The compabilities of this mount with F8 are on the limits... On a "good" night, I manage to guide my PDS down to Total 0.4" error, however usual guiding error is around 0.6", - most likely it is not enough... Recuder? mmm... in this case I can stay with PDS don't I?

3) Focuser... I afraid the default one will not manage to carry such amount of "toys" without causing problems... or not?

4) Primary Mirror, - will it hold the colimation and focus after Meridian Flip? As far as I have managed to find info online, some say no, some say yes for 8" as new versions have slightly upgraded Primary holder, but also no for 6"... Confusing...

5) Not much pictures online which are done using this scope ... A bit scary...

6) Will I need to get any kind of corrector if I am planning to stay on the native FL and do not use reducer?

 

The scope in question: https://www.ioptron.com/product-p/6112.htm

P.S.

And yes... EdgeHD would be my primary toy to go for... But damn... The price is not in my range...

 

 

Edited October 24, 2022 by RolandKol

[Clarkey]

I have the StellaLyra (GSO) RC8 and use it for imaging and I have found it to be excellent. (Similar to the iOptron but there may be some differences - StellaLyra 8" f/8 M-LRS Ritchey-Chrétien Telescope OTA | First Light Optics). Personally, I think it is bargain for what you get when comparing with an SCT etc. Answering your questions in order:

1. It is a narrow FOV but excellent for smaller targets. Not really a planetary scope though, but good for galaxy imaging.

2. As long as your guiding is 1/2 your resolution you should be OK. With a binned 2x2 ASI1600 it would give you just under 1"/pixel which is probably more than your seeing can support anyway. So your mount should be OK. With the CCD47 you can reduce you FL to around 1200mm (or whatever you want within reason).

3. I cannot answer for the iOptron focuser, but the GSO one was OK - but I did swap mine for a Baader ST. Probably not essential depending how fussy you are and which auto focuser you use. There was some slight slippage but only during autofocus routines (and not enough to be a major problem).

4. Never had a problem with meridian flips. No evidence for mirror movement. Collimation is not as hard as most seem to suggest - and once collimated it hold really well.

5. Some images M51, Coma Cluster and Hickson 44 (Leo Quartet):

Edited October 24, 2022 by Clarkey

[RolandKol]

10 minutes ago, Clarkey said:

I have the StellaLyra (GSO) RC8 and use it for imaging and I have found it to be excellent. (Similar to the iOptron but there may be some differences - StellaLyra 8" f/8 M-LRS Ritchey-Chrétien Telescope OTA | First Light Optics). Personally, I think it is bargain for what you get when comparing with an SCT etc. Answering your questions in order:

1. It is a narrow FOV but excellent for smaller targets. Not really a planetary scope though, but good for galaxy imaging.

2. As long as your guiding is 1/2 your resolution you should be OK. With a binned 2x2 ASI1600 it would give you just under 1"/pixel which is probably more than your seeing can support anyway. So your mount should be OK. With the CCD47 you can reduce you FL to around 1200mm (or whatever you want within reason).

3. I cannot answer for the iOptron focuser, but the GSO one was OK - but I did swap mine for a Baader ST. Probably not essential depending how fussy you are and which auto focuser you use. There was some slight slippage but only during autofocus routines (and not enough to be a major problem).

4. Never had a problem with meridian flips. No evidence for mirror movement. Collimation is not as hard as most seem to suggest - and once collimated it hold really well.

5. Some images M51, Coma Cluster and Hickson 44 (Leo Quartet):

Thanks a lot for the info!

As StellaLyra  is probably not much different from iOptron, - why not!

Plus, I kinda always hate brands starting from letter "i"... not sure why...

Completely forgot to add one question...

In your case, how flat is image? Should I think of any kind of corrector as a "must get/pay for". I am mostly willing to image wihout a reducer, as I will keep PDS and will be able to use it for a wider FOV's.

[Clarkey]

1 minute ago, RolandKol said:

Should I think of any kind of corrector

The RC8 works OK without - I think all of the images above were at native FL without a flattener. I think if you go for a much larger sensor you might need to get a flattener, but these were all with an ASI 1600mm so you should be fine. (I think the RC6 does need a flattener).

Just another point (looking at your set up), I did struggle a bit with the OAG due to odd star shapes - although this does appear to be a common problem. I use an ST80 for a guide scope and it does not seem to cause any flexing issues.

[RolandKol]

30 minutes ago, Clarkey said:

The RC8 works OK without - I think all of the images above were at native FL without a flattener. I think if you go for a much larger sensor you might need to get a flattener, but these were all with an ASI 1600mm so you should be fine. (I think the RC6 does need a flattener).

Just another point (looking at your set up), I did struggle a bit with the OAG due to odd star shapes - although this does appear to be a common problem. I use an ST80 for a guide scope and it does not seem to cause any flexing issues.

Yep, with OAG,  - sometimes it is really difficult to pinpoint the position of the prism... With PDS + ASI1600 it works OK, not protruding and no shadow at all, - at least in my case and it took quite awhile to adjust it correctly.
With RC8 (if I will get it) I will test with my Evoguide first, but it will cause "The imaging / guiding ratio 1 : 6.62 " .  It does not look good on the paper... On another hand, if guiding will be around 0.5" error anyway...

 

Edited October 24, 2022 by RolandKol

[RolandKol]

Just found this vid, - about RC lack/incorrect baffling.

is this something usual and I should actually worry about?

The problem, - I image almost from under the bloody street lights....

Good news, - I do own 3D printer and even 2 left hands