Robindonne

Yes for me it’s clear. Thanks very much

And while reading it again i see the curvature corrector mentioned🤭

https://www.explorescientific.co.uk/en/EXPLORE-SCIENTIFIC-MPCC-Field-Flatt-ED-APO-Canon-EOS-T2.html it’s this one

No ok i understand. But asked it because while searching the es site for the description of the mpcc, i read some reviews about the lack of information given with their products, and one person even wrote to have used the es mpcc, for a long time, with 45 mm instead of the 55 mm in the later added description. I guess he must have never noticed something.

Sorry you are right. The initial name of the thread was “es mpcc??” I changed it but forgot tho mention the brand. Excuse me😬

I think you are one of the people who knows the answer on this: what happens when the backfocus isnt the same as mention in the description? Does it harm the whole image?

Yes thats what i thought. But it could indeed mean curvature like mentioned here by alacant. This is baaders short for coma corrector. But it could be correct that explore scientific uses cc as short for curvature corrector

Ah ok thx. Yes thats not coma😏.

I would prepare for later steps and pick one of this list. Its for later use with stellarmate, eagle and asiair. The models that say “tested” work with all above systems for perhaps later automation

Oh thanks for offering pics. But im really not in the position to judge them😬. Maybe in a year or more. But for this moment im still in a learning phase

Does anyone know what the explore scientific mpcc actually is? Does mpcc mean multipurpose coma corrector? i bought one that has a 2” connection on the telescope side and a canon connection on the camera side. Removing the canon mount leaves a t-thread. And removing the 2” tube leaves only a glass correcting thing. Sold in this setup as flattener for using a canon dslr with refractors. But does the mpcc mean that the same base can be sold/used as coma corrector for my newton? And therefore is the same product?

Ok while this post is almost finished. One last ??? What does mpcc stand for?

Oh okay. Wanted to ask why it is this much cheaper then the most alternatives. Mine is a quattro8 f4. And even though i dont have any experience with these issues, i dont want to rebuy another one later due to my fear of more astro paperweights. But basically the aplanatic from skywatcher (the one thats reviewed very very good for the Quattro’s), and many other 55 mm backfocus needed cc’s, leaves only room for 10-12 mm between the oag and camera housing. Thats very tiny. It means buying a third thin oag😑. Probably better go safe for a skywatcher cc with an asi camera and use my existing oag.

The gso is not available at flo nor in the netherlands. The germans offer one that looks the same. Also the 75 mm. But is it any good?

Very much thx. This is the one that will be on its way to Nl soon

Wow. To solve one problem you receive another one for free. Oke. The 45 is swallowed by the dslr that gives me 10 mm left for oag and ring. Thats tight. Then im glad im still free to choose the gso cc. Im really curious to the problems that will bring😅

Do you think i get in trouble when between the cc and dslr is 16 mm space used by the oag?Or does the required backfocus of 55 mm mean that between the cc and dslr sensor 55 mm is required? When thats the case i need to extend more. Strange because i had to move the focuser almost completely in to get focus(no coma corrector)

Oke very helpfull thx. So to make my setups complete and good... my newtonian is now equipped with my oag and dslr. Need to look for a better guide camera and a comacorrector to make te whole setup complete. i bought another sct-oag/360 rotator(secondhand but cheap and unused/sealed) for the occasional use of my c8. Bought is because it came for sale and the mentioned refocussing of the oag-guidecam when swapping an oag between scopes. This setup also gets the better guidecam to make it complete also. whats left are two old ed refractors. Kind of planned to use as guiders when not used as mainscopes, but the oag’s are the guiders from now on. So my final question ( for now😬) would be: how to guide the refractors? Also the oag (what some mentioned an overkill) or for this maybe a small guidescope? Both zenithstars and both need extenders to get in focus. I would prefer spending another 80,- on a thick oag then on a simple 2” extender. my budget is not made of 6 figures but spending money on the right stuff (instead of the earlier mentioned “asi120-paper-weight) is always justified. -better guidecam like the asi290 mono? -f4 aplanatic coma corrector -small guidescope for the refractors or also oag? its rainy and cloudy here in the best soccer/f1 country, so plenty of time to look for missing items.

Thx for all the reply’s. What i read between the lines is: get an as good as possible guidecam for using an oag, and a more medium cam will work with a more open guider(50mm-80mm). And second use the oag for the newton. So another asi order is inevitable 🥳🇨🇳. I had a related question but I forgot. Thx so far. Ill go check the calculators the next two days at least😞

You see?! 4!!

Hm ok. Thats something i wasnt aware of. Its probably not explained in two sentences so i better google for the way of calculating the pixel scale. Im using a dslr. And from what I remember it says imaging in the somewhere region of 5000x3500 pixels. With an 8” newtonian. My asi120 has a resolution of 1280x960. When i compare resolution then i would end up using a 50 mm guidescope with the asi120. But thats only based on the diameter of the newton. I dont know if fov is involved in this calculation. If not then Im gonna try guiding with that 71 mm refractor.

Thx. Thats what i was hoping for

No your right. From all the cons that come with an oag, the reflectors were kind of 50/50. Due to mirror movements it would be a good choise to go for an oag. But overall the oag would be second choise. Thats what the advices told me. And despite all the advices i bought an oag and found out. But i use the cheapest cam, no coma correction and have 38 years of inexperience in me😬. as an amateur-amateur i will probably have more fun and useful hours when swapping the oag for a guidescope when i use the newton. When that setup is running i can spend some time playing with the oag on a c8 for example. Only thing i dont know for sure is/was to make my finder a guider or go for seperate guidescope. Or even use a small zenithstar for guiding that newton

Ok i have to admit you were all right about the benefits of a guidescope over an oag. Especially when using on an un-comacorrected newton with an asi120 as guidecam. Ive started to swap my setup and ended with a big mountingplate and 125 mm guiderings on the newton. Lets say weight is no problem, should i use a small (71mm) refractor(already have it), or make a guidescope of my 9x50 finderscope(have one extra for finderuse), or go for a 60 mm guidescope like an altair or some sort of? If my oag would have worked with a better camera and comacorrected view, then the finderscope-update would be enough i guess? Just dont want to spend €40,- for an 9x50 to t-mount adapter when the result is bad enough to, in the end, buy a €100,- guidescope that is build for that job. If the rebuild finderscope is adviced, it will end up in the guiderings. So no problems with the standard “2 screws/1 spring” housing. its all finding its final destination on a eq6r. If a cem70 is not spoiling my skywatcher sale.

Ha yes but already owned some astro paper weights🙄